Sample records for radiation therapy igrt
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Energy Technology Data Exchange (ETDEWEB)
Nabavizadeh, Nima, E-mail: nabaviza@ohsu.edu [Department of Radiation Medicine, Oregon Health & Science University, Portland, Oregon (United States); Elliott, David A. [Department of Radiation Medicine, Oregon Health & Science University, Portland, Oregon (United States); Chen, Yiyi [Division of Biostatistics, Department of Public Health and Preventative Medicine, Oregon Health & Science University, Portland, Oregon (United States); Kusano, Aaron S. [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States); Mitin, Timur; Thomas, Charles R.; Holland, John M. [Department of Radiation Medicine, Oregon Health & Science University, Portland, Oregon (United States)
2016-03-15
Purpose: To survey image guided radiation therapy (IGRT) practice patterns, as well as IGRT's impact on clinical workflow and planning treatment volumes (PTVs). Methods and Materials: A sample of 5979 treatment site–specific surveys was e-mailed to the membership of the American Society for Radiation Oncology (ASTRO), with questions pertaining to IGRT modality/frequency, PTV expansions, method of image verification, and perceived utility/value of IGRT. On-line image verification was defined as images obtained and reviewed by the physician before treatment. Off-line image verification was defined as images obtained before treatment and then reviewed by the physician before the next treatment. Results: Of 601 evaluable responses, 95% reported IGRT capabilities other than portal imaging. The majority (92%) used volumetric imaging (cone-beam CT [CBCT] or megavoltage CT), with volumetric imaging being the most commonly used modality for all sites except breast. The majority of respondents obtained daily CBCTs for head and neck intensity modulated radiation therapy (IMRT), lung 3-dimensional conformal radiation therapy or IMRT, anus or pelvis IMRT, prostate IMRT, and prostatic fossa IMRT. For all sites, on-line image verification was most frequently performed during the first few fractions only. No association was seen between IGRT frequency or CBCT utilization and clinical treatment volume to PTV expansions. Of the 208 academic radiation oncologists who reported working with residents, only 41% reported trainee involvement in IGRT verification processes. Conclusion: Consensus guidelines, further evidence-based approaches for PTV margin selection, and greater resident involvement are needed for standardized use of IGRT practices.
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Keall, Paul J; Nguyen, Doan Trang; O'Brien, Ricky; Zhang, Pengpeng; Happersett, Laura; Bertholet, Jenny; Poulsen, Per R
2018-04-14
To review real-time 3-dimensional (3D) image guided radiation therapy (IGRT) on standard-equipped cancer radiation therapy systems, focusing on clinically implemented solutions. Three groups in 3 continents have clinically implemented novel real-time 3D IGRT solutions on standard-equipped linear accelerators. These technologies encompass kilovoltage, combined megavoltage-kilovoltage, and combined kilovoltage-optical imaging. The cancer sites treated span pelvic and abdominal tumors for which respiratory motion is present. For each method the 3D-measured motion during treatment is reported. After treatment, dose reconstruction was used to assess the treatment quality in the presence of motion with and without real-time 3D IGRT. The geometric accuracy was quantified through phantom experiments. A literature search was conducted to identify additional real-time 3D IGRT methods that could be clinically implemented in the near future. The real-time 3D IGRT methods were successfully clinically implemented and have been used to treat more than 200 patients. Systematic target position shifts were observed using all 3 methods. Dose reconstruction demonstrated that the delivered dose is closer to the planned dose with real-time 3D IGRT than without real-time 3D IGRT. In addition, compromised target dose coverage and variable normal tissue doses were found without real-time 3D IGRT. The geometric accuracy results with real-time 3D IGRT had a mean error of real-time 3D IGRT methods using standard-equipped radiation therapy systems that could also be clinically implemented. Multiple clinical implementations of real-time 3D IGRT on standard-equipped cancer radiation therapy systems have been demonstrated. Many more approaches that could be implemented were identified. These solutions provide a pathway for the broader adoption of methods to make radiation therapy more accurate, impacting tumor and normal tissue dose, margins, and ultimately patient outcomes. Copyright © 2018
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International Nuclear Information System (INIS)
Lief, Eugene
2008-01-01
Two definitions of image-guided radiation therapy (IGRT) are cited: 'Frequent imaging in the treatment room during a course of radiotherapy to guide the treatment process' and 'Any use of planar imaging, volumetric imaging or volumetric cine imaging, marker localization, marker tracking, patient surface imaging or patient surface tracking to improve the precision of radiation-therapy delivery'. Also cited are the sentences 'IGRT refers broadly to treatment delivery using modern imaging methods, such as CT, MRI, PET and Ultrasound, in target and non-target structures and in RT definition, design and delivery...' and 'IGRT includes, but is not limited to, 3DCRT, IMRT: stereotactic radiosurgery, stereotactic RT, and brachytherapy...'. Purposes include: Precise patient positioning; Automatic localization of bony structures or implanted fiducial markers; Imaging and positioning of soft tissue tumors and critical structures; Margin reduction and healthy organ sparing; and Delivering the desired dose distribution. On the negative side are the following factors: Physics staffing at treatment delivery Longer treatment times: 1 min. arm deployment, setup for scan, 1 min. gantry rotation - volume image acquisition, 30 sec. reconstruction (depends on resolution), 30 sec. load CT and CB into registration; Registration: from few sec. to few min.; Feasible if the number of treatments is low. The history of IGRT is mentioned, instrumentation is described using ample photographs, and many applications are shown. (P.A.)
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The physics of radiation therapy
Khan, Faiz M
2009-01-01
Dr. Khan's classic textbook on radiation oncology physics is now in its thoroughly revised and updated Fourth Edition. It provides the entire radiation therapy team—radiation oncologists, medical physicists, dosimetrists, and radiation therapists—with a thorough understanding of the physics and practical clinical applications of advanced radiation therapy technologies, including 3D-CRT, stereotactic radiotherapy, HDR, IMRT, IGRT, and proton beam therapy. These technologies are discussed along with the physical concepts underlying treatment planning, treatment delivery, and dosimetry. This Fourth Edition includes brand-new chapters on image-guided radiation therapy (IGRT) and proton beam therapy. Other chapters have been revised to incorporate the most recent developments in the field. This edition also features more than 100 full-color illustrations throughout.
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International Nuclear Information System (INIS)
Hess, Clayton B.; Thompson, Holly M.; Benedict, Stanley H.; Seibert, J. Anthony; Wong, Kenneth; Vaughan, Andrew T.; Chen, Allen M.
2016-01-01
Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning—a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and, because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of “gentle IGRT.”
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Energy Technology Data Exchange (ETDEWEB)
Hess, Clayton B. [Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California (United States); Thompson, Holly M. [Department of Diagnostic Radiology, University of California Davis Medical Center, Sacramento, California (United States); Benedict, Stanley H. [Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California (United States); Seibert, J. Anthony [Department of Diagnostic Radiology, University of California Davis Medical Center, Sacramento, California (United States); Wong, Kenneth [Department of Radiation Oncology, University of California Los Angeles Jonsson Comprehensive Cancer Center, University of California David Geffen School of Medicine, Los Angeles, California (United States); Vaughan, Andrew T. [Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California (United States); Chen, Allen M., E-mail: allenmchen@yahoo.com [Department of Radiation Oncology, University of California Los Angeles Jonsson Comprehensive Cancer Center, University of California David Geffen School of Medicine, Los Angeles, California (United States)
2016-04-01
Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning—a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and, because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of “gentle IGRT.”.
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Estimation of radiation load of patient during IGRT image radiotherapy procedures
International Nuclear Information System (INIS)
Nechvil, K.; Mynarik, J.; Dolezel, M.; Minarikova, I.
2009-01-01
In this poster the methods of quantitative estimation of doses for lower imaging modalities used at IGRT are described. They are applied for actual scenario: therapy by IGRT used at radiotherapeutic department RC Multiscan Pardubice. Defined results are compared with values available from literature and evaluation of risk from these doses is made
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Energy Technology Data Exchange (ETDEWEB)
Monroe, Alan T.; Peddada, Anuj V. [Dept. of Radiation Oncology, Penrose Cancer Center, Colorado Springs (United States); Pikaart, Dirk [Dept. of Gynecologic Oncology, Penrose Cancer Center, Colorado Springs (United States)
2013-06-15
Objective. To report two year clinical outcomes of image guided radiation therapy (IGRT) to the vaginal cuff and pelvic lymph nodes in a series of high-risk endometrial cancer patients. Methods . Twenty-six consecutive high-risk endometrial cancer patients requiring adjuvant radiation to the vaginal cuff and regional lymph nodes were treated with vaginal cuff fiducial-based IGRT. Seventeen (65%) received sequential chemotherapy, most commonly with a sandwich technique. Brachytherapy followed external radiation in 11 patients to a median dose of 18 Gy in 3 fractions. The median external beam dose delivered was 47.5 Gy in 25 fractions. Results. All 656 fractions were successfully imaged and treated. The median overall translational shift required for correction was 9.1 mm (standard deviation, 5.2 mm) relative to clinical set-up with skin tattoos. Shifts of 1 cm, 1.5 cm, and 2 cm or greater were performed in 43%, 14%, and 4% of patients, respectively. Acute grade 2 gastrointestinal (GI) toxicity occurred in eight patients (30%) and grade 3 toxicity occurred in one. At two years, there have been no local or regional failures and actuarial overall survival is 95%. Conclusion. Daily image guidance for high-risk endometrial cancer results in a low incidence of acute GI/genitourinary (GU) toxicity with uncompromised tumor control at two years. Vaginal cuff translations can be substantial and may possibly result in underdosing if not properly considered.
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International Nuclear Information System (INIS)
Monroe, Alan T.; Peddada, Anuj V.; Pikaart, Dirk
2013-01-01
Objective. To report two year clinical outcomes of image guided radiation therapy (IGRT) to the vaginal cuff and pelvic lymph nodes in a series of high-risk endometrial cancer patients. Methods . Twenty-six consecutive high-risk endometrial cancer patients requiring adjuvant radiation to the vaginal cuff and regional lymph nodes were treated with vaginal cuff fiducial-based IGRT. Seventeen (65%) received sequential chemotherapy, most commonly with a sandwich technique. Brachytherapy followed external radiation in 11 patients to a median dose of 18 Gy in 3 fractions. The median external beam dose delivered was 47.5 Gy in 25 fractions. Results. All 656 fractions were successfully imaged and treated. The median overall translational shift required for correction was 9.1 mm (standard deviation, 5.2 mm) relative to clinical set-up with skin tattoos. Shifts of 1 cm, 1.5 cm, and 2 cm or greater were performed in 43%, 14%, and 4% of patients, respectively. Acute grade 2 gastrointestinal (GI) toxicity occurred in eight patients (30%) and grade 3 toxicity occurred in one. At two years, there have been no local or regional failures and actuarial overall survival is 95%. Conclusion. Daily image guidance for high-risk endometrial cancer results in a low incidence of acute GI/genitourinary (GU) toxicity with uncompromised tumor control at two years. Vaginal cuff translations can be substantial and may possibly result in underdosing if not properly considered
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Introduction to IGRT and additional components
International Nuclear Information System (INIS)
Mijnheer, Ben
2008-01-01
Image-guided radiation therapy is 'Any use of planar imaging, volumetric imaging or volumetric cine imaging, marker localization, marker tracking, patient surface imaging or patient surface tracking to improve the precision of radiation-therapy delivery' , or 'Frequent imaging in the treatment room during a course of radiotherapy to guide the treatment process'. Purpose: To verify if the correct volume in a patient is irradiated by imaging the target and/or healthy tissue prior to or during treatment. Imaging modalities include: Electronic Portal Imaging Devices (EPIDs); (Portal) imaging of implanted markers; Imaging of external markers; Ultrasound; X-ray fluoroscopy; and CT (MR) scanner in treatment room. Final remarks are as follows: The introduction of various IGRT techniques allowed 3D verification of the position of target volumes and organs at risk just before or during treatment. Because the information is in 3D, or sometimes even in 4D, in principle these IGRT approaches provide more information compared to the use of 2D verification methods (e.g. EPIDs). Clinical data are becoming available to assess quantitatively for which treatment techniques IGRT approaches are advantageous compared to the use of conventional verification methods taking the additional resources (time, money, manpower) into account. (P.A.)
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Image-guided radiation therapy: physician's perspectives
International Nuclear Information System (INIS)
Gupta, T.; Anand Narayan, C.
2012-01-01
The evolution of radiotherapy has been ontogenetically linked to medical imaging. Over the years, major technological innovations have resulted in substantial improvements in radiotherapy planning, delivery, and verification. The increasing use of computed tomography imaging for target volume delineation coupled with availability of computer-controlled treatment planning and delivery systems have progressively led to conformation of radiation dose to the target tissues while sparing surrounding normal tissues. Recent advances in imaging technology coupled with improved treatment delivery allow near-simultaneous soft-tissue localization of tumor and repositioning of patient. The integration of various imaging modalities within the treatment room for guiding radiation delivery has vastly improved the management of geometric uncertainties in contemporary radiotherapy practice ushering in the paradigm of image-guided radiation therapy (IGRT). Image-guidance should be considered a necessary and natural corollary to high-precision radiotherapy that was long overdue. Image-guided radiation therapy not only provides accurate information on patient and tumor position on a quantitative scale, it also gives an opportunity to verify consistency of planned and actual treatment geometry including adaptation to daily variations resulting in improved dose delivery. The two main concerns with IGRT are resource-intensive nature of delivery and increasing dose from additional imaging. However, increasing the precision and accuracy of radiation delivery through IGRT is likely to reduce toxicity with potential for dose escalation and improved tumor control resulting in favourable therapeutic index. The radiation oncology community needs to leverage this technology to generate high-quality evidence to support widespread adoption of IGRT in contemporary radiotherapy practice. (author)
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Energy Technology Data Exchange (ETDEWEB)
Cui Yunfeng [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Galvin, James M. [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Radiation Therapy Oncology Group, American College of Radiology, Philadelphia, Pennsylvania (United States); Parker, William [Department of Medical Physics, McGill University Health Center, Montreal, QC (Canada); Breen, Stephen [Department of Radiation Physics, Princess Margaret Hospital, Toronto, ON (Canada); Yin Fangfang; Cai Jing [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Papiez, Lech S. [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Bednarz, Greg [Department of Radiation Oncology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Chen Wenzhou [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Xiao Ying, E-mail: ying.xiao@jefferson.edu [Department of Radiation Oncology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Radiation Therapy Oncology Group, American College of Radiology, Philadelphia, Pennsylvania (United States)
2013-01-01
Purpose: To report the process and initial experience of remote credentialing of three-dimensional (3D) image guided radiation therapy (IGRT) as part of the quality assurance (QA) of submitted data for Radiation Therapy Oncology Group (RTOG) clinical trials; and to identify major issues resulting from this process and analyze the review results on patient positioning shifts. Methods and Materials: Image guided radiation therapy datasets including in-room positioning CT scans and daily shifts applied were submitted through the Image Guided Therapy QA Center from institutions for the IGRT credentialing process, as required by various RTOG trials. A centralized virtual environment is established at the RTOG Core Laboratory, containing analysis tools and database infrastructure for remote review by the Physics Principal Investigators of each protocol. The appropriateness of IGRT technique and volumetric image registration accuracy were evaluated. Registration accuracy was verified by repeat registration with a third-party registration software system. With the accumulated review results, registration differences between those obtained by the Physics Principal Investigators and from the institutions were analyzed for different imaging sites, shift directions, and imaging modalities. Results: The remote review process was successfully carried out for 87 3D cases (out of 137 total cases, including 2-dimensional and 3D) during 2010. Frequent errors in submitted IGRT data and challenges in the review of image registration for some special cases were identified. Workarounds for these issues were developed. The average differences of registration results between reviewers and institutions ranged between 2 mm and 3 mm. Large discrepancies in the superior-inferior direction were found for megavoltage CT cases, owing to low spatial resolution in this direction for most megavoltage CT cases. Conclusion: This first experience indicated that remote review for 3D IGRT as part of QA
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Hendee's radiation therapy physics
Pawlicki, Todd; Starkschall, George
2016-01-01
The publication of this fourth edition, more than ten years on from the publication of Radiation Therapy Physics third edition, provides a comprehensive and valuable update to the educational offerings in this field. Led by a new team of highly esteemed authors, building on Dr Hendee’s tradition, Hendee’s Radiation Therapy Physics offers a succinctly written, fully modernised update. Radiation physics has undergone many changes in the past ten years: intensity-modulated radiation therapy (IMRT) has become a routine method of radiation treatment delivery, digital imaging has replaced film-screen imaging for localization and verification, image-guided radiation therapy (IGRT) is frequently used, in many centers proton therapy has become a viable mode of radiation therapy, new approaches have been introduced to radiation therapy quality assurance and safety that focus more on process analysis rather than specific performance testing, and the explosion in patient-and machine-related data has necessitated an ...
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Treatment plan quality of tri-Co-60 MR-IGRT system in comparison with that of VMAT
Energy Technology Data Exchange (ETDEWEB)
Park, Jong Min; Park, So Yeon; Kim, Jung In [Dept. of Nuclear Engineering, Seoul National University Hospital, Seoul (Korea, Republic of); Kim, Hak Jae; Wu, Hong Gyun [Dept. of Nuclear Engineering, Seoul National University College of Medicine, Seoul (Korea, Republic of)
2016-04-15
The ViewRay{sup TM} system combines a 0.35-T MR imaging system and a radiation therapy system using a total of three Co-60 sources. It can perform static intensity-modulated radiation therapy (IMRT) with multi-leaf collimators (MLCs) with leaf widths of 1.05 cm at the plane of isocenter, at source to axis distance (SAD) of 105 cm. Since the tri-Co-60 MR-IGRT system can acquire near-real-time cine sagittal MR images during treatment, automated respiratory gating can be performed based on these cine images, thus, the target margins for lung stereotactic ablative radiotherapy (SABR) could be reduced considerably by comparison with the internal tarvet volume (ITV) approach. we compared lung SABR treatment plans of the tri-Co-60 MR-IGRT system with gross tumor volume (GTV) to those of volumetric modulated arc therapy (VMAT) using TrueBeam STx™ (Varian Medical Systems, Palo Alto, CA) with ITV in this study. The plan quality of the target volume of the VMAT with ITV was better than that of the GTV-based tri-Co-60 MR-IGRT for lung SABR. No significant differences for OARs were observed between the tri-Co-60 MR-IGRT and VMAT. However, the plan quality of the tri-Co-60 MR-IGRT system was clinically acceptable. Despite the relatively poor plan quality of the tri-Co-60 MR-IGRT system, it still has the advantage of real-time monitoring of tumor motion during treatment.
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Non-radiographic methods for IGRT
International Nuclear Information System (INIS)
Semwal, Manoj K.
2016-01-01
The primary goal of radiation therapy is to deliver a tumouricidal dose within a defined target volume while minimizing dose to surrounding normal tissues. In recent years, advanced technologies such as intensity modulated radiotherapy (IMRT), stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT) have been used to meet the goal. High dose conformity and steep dose gradients beyond the target volume achieved with these technologies warrant high level of accuracy in the dose delivery. Therefore, accurate patient localization, target segmentation and motion compensation have become mandatory requirements. Several technologies have been developed over the years to image the patient for treatment planning and for subsequent daily imaging/tracking while the patient is on the treatment table. For image guided radiotherapy (IGRT) some of the technologies are kilovoltage (kV) x-rays imaging, in-room computed tomography (CT), kV and MV cone-beam CT(CBCT). One of the chief drawbacks of these technologies is addition of radiation dose to the patients. There are other technologies that do not use ionizing radiation such as USG, MRI, patient surface monitoring using infrared and optical radiation, and radiofrequency (RF)-based localization/tracking systems that are also being developed for the purpose. These technologies may be collectively called as non-radiographic (NR) technologies for IGRT
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IGRT yesterday, today and tomorrow
International Nuclear Information System (INIS)
Xing, Lei
2008-01-01
Recent technical advances in planning and delivering IMRT provide an unprecedented means for producing exquisitely shaped radiation doses that closely conform to the tumor dimensions while sparing sensitive structures. The development of 3D CRT and IMRT places more stringent requirements on the accuracy of beam targeting. In practice, large uncertainties exist in tumor volume delineation and in target localization due to intra- and inter-organ motions. The utility of modern radiation technologies, such as 3D CRT and IMRT, cannot be fully exploited without eliminating or significantly reducing these uncertainties. The need to improve targeting in radiation treatment has recently spurred a flood of research activities in image-guided radiation therapy (IGRT)
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TU-A-201-02: Treatment Site-Specific Considerations for Clinical IGRT
Energy Technology Data Exchange (ETDEWEB)
Wijesooriya, K. [University of Virginia Health Systems (United States)
2016-06-15
Recent years have seen a widespread proliferation of available in-room image guidance systems for radiation therapy target localization with many centers having multiple in-room options. In this session, available imaging systems for in-room IGRT will be reviewed highlighting the main differences in workflow efficiency, targeting accuracy and image quality as it relates to target visualization. Decision-making strategies for integrating these tools into clinical image guidance protocols that are tailored to specific disease sites like H&N, lung, pelvis, and spine SBRT will be discussed. Learning Objectives: Major system characteristics of a wide range of available in-room imaging systems for IGRT. Advantages / disadvantages of different systems for site-specific IGRT considerations. Concepts of targeting accuracy and time efficiency in designing clinical imaging protocols.
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International Nuclear Information System (INIS)
Tsuboi, Kazuki; Yagi, Masayuki; Fujiwara, Kanta
2013-01-01
The linear accelerator with image guided radiation therapy (IGRT) was introduced in May 2010. We performed the verification of the IGRT system, id est (i.e.), acceptance test and our original performance test and confirmed the acceptability for clinical use. We also performed daily QA/QC program before the start of treatment. One-year experience of QA/QC program showed excellent stability of IGRT function compared with our old machine. We further hope to establish the more useful management system and QA/QC program. (author)
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Clinical Implementation Of Megavoltage Cone Beam CT As Part Of An IGRT Program
International Nuclear Information System (INIS)
Gonzalez, Albin; Kinney, Vicki; Crooks, Cheryl; Bauer, Lisa
2008-01-01
Knowing where the tumor is at all times during treatment is the next challenge in the field of radiation therapy. This issue has become more important because with treatments such as Intensity Modulated Radiation Therapy (IMRT), healthy tissue is spared by using very tight margins around the tumor. These tight margins leave very small room for patient setup errors. The use of an imaging modality in the treatment room as a way to localize the tumor for patient set up is generally known as ''Image Guided Radiation Therapy'' or IGRT. This article deals with a form of IGRT known as Megavoltage Cone Beam Computed Tomography (MCBCT) using a Siemens Oncor linear accelerator currently in use at Firelands Regional Medical Center. With MCBCT, we are capable of acquiring CT images right before the treatment of the patient and then use this information to position the patient tumor according to the treatment plan. This article presents the steps followed in order to clinically implement this system, as well as some of the quality assurance tests suggested by the manufacturer and some tests developed in house
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The role of Cobalt-60 in modern radiation therapy: Dose delivery and image guidance
Directory of Open Access Journals (Sweden)
Schreiner L
2009-01-01
Full Text Available The advances in modern radiation therapy with techniques such as intensity-modulated radiation therapy and image-guid-ed radiation therapy (IMRT and IGRT have been limited almost exclusively to linear accel-erators. Investigations of modern Cobalt-60 (Co-60 radiation delivery in the context of IMRT and IGRT have been very sparse, and have been limited mainly to computer-modeling and treatment-planning exercises. In this paper, we report on the results of experiments using a tomotherapy benchtop apparatus attached to a conventional Co-60 unit. We show that conformal dose delivery is possible and also that Co-60 can be used as the radiation source in megavoltage computed tomography imaging. These results complement our modeling studies of Co-60 tomotherapy and provide a strong motivation for continuing development of modern Cobalt-60 treatment devices.
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Energy Technology Data Exchange (ETDEWEB)
Rankine, L; Klein, E [Washington University, Saint Louis, MO (United States); Grantham, K [University of Missouri, Columbia, MO (United States); Goddu, S [Washington University, St. Louis, MO (United States); Cessac, R [Mevion Medical Systems, Littleton, MA (United States); Baker, K [Barne-Jewish Hospital, St. Louis, MO (United States); Santanam, L [Washington University School of Medicine, St.louis, MO (United States)
2014-06-01
Purpose: The Mevion S250 proton therapy unit is equipped with a 6D-robotic couch and IGRT system (Verity). The patient alignment process allows corrections in six degrees of freedom: translation (x,y,z), pitch, roll, and yaw (θ,ϑ,ψ). Geometric accuracy of couch corrections and imaging vs. radiation isocenter coincidence were quantified before clinical implementation. Methods: A commercial phantom with sixteen 2mm tungsten BBs was rigidly couch-mounted and imaged with CT. Seventeen rigid translations/rotations of known magnitude were digitally applied to the original CT image using commercial software, validated with Varian OBI system. For each altered image, phantom was mounted on robotic couch in original position, then Verity 2D:2D match (PA-LLAT) was performed using DRRs from altered images. Corrections were recorded and applied, phantom was imaged a second time and residual corrections recorded. Physical measurements verified that applied couch corrections coincided with both physical couch shifts/rotations and known CT image translations/rotations. Additionally, image vs. radiation isocenter coicidence was quantified over couch treatment angles (±90° from setup position) using radiochromic film and an image-guided couch star-shot. Posterior-anterior and left-lateral kV radiographs were taken before each beam was delivered to verify imaging/radiation isocentricity. Results: Verity suggested couch corrections and known CT shifts/rotations agreed within ±1mm (average: Δ lat=0.5mm; Δ vert=0.4mm; Δ long=0.3mm) and ± 0.4° (average: Δ pitch=0.24° Δ roll=0.01°; Δ yaw=0.10°). Physical couch measurements and Verity applied corrections agreed within ± 1mm (average: Δlat=0.5mm; Δvert=0.4mm; Δlong=0.2mm) and ±0.2° (average: Δpitch=0.03°; Δ roll=0.04°; Δ yaw=0.04°). The directionality of all translations and rotations were qualitatively verified. The image vs. radiation isocenter coincidence was <1mm and radiation-isocenter precision was <1mm
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International Nuclear Information System (INIS)
Torfeh, Tarraf
2009-01-01
On-board imagers mounted on a radiotherapy treatment machine are very effective devices that improve the geometric accuracy of radiation delivery. However, a precise and regular quality control program is required in order to achieve this objective. Our purpose consisted of developing software tools dedicated to an automatic image quality control of IGRT devices used in external radiotherapy: 2D-MV mode for measuring patient position during the treatment using high energy images, 2D-kV mode (low energy images) and 3D Cone Beam Computed Tomography (CBCT) MV or kV mode, used for patient positioning before treatment. Automated analysis of the Winston and Lutz test was also proposed. This test is used for the evaluation of the mechanical aspects of treatment machines on which additional constraints are carried out due to the on-board imagers additional weights. Finally, a technique of generating digital phantoms in order to assess the performance of the proposed software tools is described. Software tools dedicated to an automatic quality control of IGRT devices allow reducing by a factor of 100 the time spent by the medical physics team to analyze the results of controls while improving their accuracy by using objective and reproducible analysis and offering traceability through generating automatic monitoring reports and statistical studies. (author) [fr
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International Nuclear Information System (INIS)
Giaddui, T; Chen, W; Yu, J; Gong, Y; Galvin, J; Xiao, Y; Cui, Y; Yin, F; Craig, T; Dawson, L; Al-Hallaq, H; Chmura, S
2014-01-01
Purpose: To review IGRT credentialing experience and unexpected technical issues encountered in connection with advanced radiotherapy technologies as implemented in RTOG clinical trials. To update IGRT credentialing procedures with the aim of improving the quality of the process, and to increase the proportion of IGRT credentialing compliance. To develop a living disease site-specific IGRT encyclopedia. Methods: Numerous technical issues were encountered during the IGRT credentialing process. The criteria used for credentialing review were based on: image quality; anatomy included in fused data sets and shift results. Credentialing requirements have been updated according to the AAPM task group reports for IGRT to ensure that all required technical items are included in the quality review process. Implementation instructions have been updated and expanded for recent protocols. Results: Technical issues observed during the credentialing review process include, but are not limited to: poor quality images; inadequate image acquisition region; poor data quality; shifts larger than acceptable; no soft tissue surrogate. The updated IGRT credentialing process will address these issues and will also include the technical items required from AAPM: TG 104; TG 142 and TG 179 reports. An instruction manual has been developed describing a remote credentialing method for reviewers. Submission requirements are updated, including images/documents as well as facility questionnaire. The review report now includes summary of the review process and the parameters that reviewers check. We have reached consensus on the minimum IGRT technical requirement for a number of disease sites. RTOG 1311(NRG-BR002A Phase 1 Study of Stereotactic Body Radiotherapy (SBRT) for the Treatment of Multiple Metastases) is an example, here; the protocol specified the minimum requirement for each anatomical sites (with/without fiducials). Conclusion: Technical issues are identified and reported. IGRT
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Energy Technology Data Exchange (ETDEWEB)
Giaddui, T; Chen, W; Yu, J; Gong, Y; Galvin, J; Xiao, Y [Thomas Jefferson University, Philadelphia, PA (United States); Cui, Y; Yin, F [Duke University Medical Center, Durham, NC (United States); Craig, T; Dawson, L [The Princess Margaret Cancer Centre - UHN, Toronto, ON (Canada); Al-Hallaq, H; Chmura, S [The University of Chicago, Chicago, IL. (United States)
2014-06-15
Purpose: To review IGRT credentialing experience and unexpected technical issues encountered in connection with advanced radiotherapy technologies as implemented in RTOG clinical trials. To update IGRT credentialing procedures with the aim of improving the quality of the process, and to increase the proportion of IGRT credentialing compliance. To develop a living disease site-specific IGRT encyclopedia. Methods: Numerous technical issues were encountered during the IGRT credentialing process. The criteria used for credentialing review were based on: image quality; anatomy included in fused data sets and shift results. Credentialing requirements have been updated according to the AAPM task group reports for IGRT to ensure that all required technical items are included in the quality review process. Implementation instructions have been updated and expanded for recent protocols. Results: Technical issues observed during the credentialing review process include, but are not limited to: poor quality images; inadequate image acquisition region; poor data quality; shifts larger than acceptable; no soft tissue surrogate. The updated IGRT credentialing process will address these issues and will also include the technical items required from AAPM: TG 104; TG 142 and TG 179 reports. An instruction manual has been developed describing a remote credentialing method for reviewers. Submission requirements are updated, including images/documents as well as facility questionnaire. The review report now includes summary of the review process and the parameters that reviewers check. We have reached consensus on the minimum IGRT technical requirement for a number of disease sites. RTOG 1311(NRG-BR002A Phase 1 Study of Stereotactic Body Radiotherapy (SBRT) for the Treatment of Multiple Metastases) is an example, here; the protocol specified the minimum requirement for each anatomical sites (with/without fiducials). Conclusion: Technical issues are identified and reported. IGRT
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Role of IGRT in patient positioning and verification
International Nuclear Information System (INIS)
Mijnheer, Ben
2008-01-01
Image-guided radiation therapy is 'Frequent imaging in the treatment room during a course of radiotherapy to guide the treatment process'. Instrumentation related to IGRT is highlighted. Focus of the lecture was on clinical experience gained by NKI-AVL, such as the use of EPID (electronic portal imaging devices) and CBCT (cone beam computed tomography) and their comparison: good results for head and neck and prostate/bladder patients: portal imaging was replaced by CBCT. After further investigation convincing results for lung patients were obtained: portal imaging was replaced by CBCT. Scan protocols were developed for these patient groups. Since February 2004 CBCT-based decision rules have been developed for: Head and Neck (Bony anatomy); Prostate (Bony anatomy; Soft tissue registration); Lung (Bony anatomy, Soft tissue registration); Brain (Bony anatomy); and Breast, bladder and liver (in progress). Final remarks are as follows: The introduction of various IGRT techniques allowed 3D verification of the position of target volumes and organs at risk just before or during treatment. Because the information is in 3D, or sometimes even in 4D, in principle these IGRT approaches provide more information compared to the use of 2D verification methods (e.g. EPIDs). Clinical data are becoming available to assess quantitatively for which treatment techniques IGRT approaches are advantageous compared to the use of conventional verification methods taking the additional resources (time, money, manpower) into account. (P.A.)
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SU-F-J-49: IGRT Credentialing in NCTN Trials
International Nuclear Information System (INIS)
Lowenstein, J; Molineu, A; Followill, D; Al-Hallaq, H; Matuszak, M; Craig, T; Ulin, K; Xiao, Y; Yin, F
2016-01-01
Purpose: To make Image Guided Radiation Therapy (IGRT) credentialing a more unified, consistent and efficient process across the entire National Clinical Trial Network (NCTN). Methods: IGRT plays a role in several advanced NCTN trials. Previously an institution had to be IGRT credentialed for each protocol. When institutions were allowed to use previous credentials for new protocols it was limited to the same disease site as the original credentialing. The credentialing was analyzed by the physics PI of the protocol. We consulted with several of these physicists to determine what is important to consider when reviewing submissions and to learn ways to apply credentialing more broadly. Results: For trials open in 2016, IGRT credentialing can be simplified to cover either boney anatomy or soft tissue. This revised credentialing will cover all disease sites based on the type of anatomy, unless otherwise stated within the protocol. Institutions will submit will complete an online questionnaire about their IGRT procedures. Boney anatomy requirements will include submission of data from 2 sequential fraction of both a patient aligned with boney anatomy and pelvic patient. Soft tissue will require similar submissions for a patient aligned using soft tissue and a pelvic patient. Institutions will only be required to submit the pelvic patient once. Data should be in DICOM format and includes planning CT set, RT structure set, RT plan file, RT dose file, localization images and spatial registration file (if available). Reviews will be done by IROC-Houston staff who will continue to provide feedback to the sites. Conclusion: This revised IGRT credentialing process will bring consistency, a savings in time and effort for both the IROC Houston QA office and to those institutions wanting to be credentialed to participate in NCTN Trials. Sponsored by NIH/NCI CA10953
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SU-F-J-49: IGRT Credentialing in NCTN Trials
Energy Technology Data Exchange (ETDEWEB)
Lowenstein, J; Molineu, A; Followill, D [UT MD Anderson Cancer Center, Houston, TX (United States); Al-Hallaq, H [The University of Chicago, Chicago, IL (United States); Matuszak, M [University of Michigan, Ann Arbor, MI (United States); Craig, T [The Princess Margaret Cancer Centre - UHN, Toronto, ON (Canada); Ulin, K [UMass Medical Center, Lincoln, RI (United States); Xiao, Y [University of Pennsylvania, Philadelphia, PA (United States); Yin, F [Duke University Medical Center, Durham, NC (United States)
2016-06-15
Purpose: To make Image Guided Radiation Therapy (IGRT) credentialing a more unified, consistent and efficient process across the entire National Clinical Trial Network (NCTN). Methods: IGRT plays a role in several advanced NCTN trials. Previously an institution had to be IGRT credentialed for each protocol. When institutions were allowed to use previous credentials for new protocols it was limited to the same disease site as the original credentialing. The credentialing was analyzed by the physics PI of the protocol. We consulted with several of these physicists to determine what is important to consider when reviewing submissions and to learn ways to apply credentialing more broadly. Results: For trials open in 2016, IGRT credentialing can be simplified to cover either boney anatomy or soft tissue. This revised credentialing will cover all disease sites based on the type of anatomy, unless otherwise stated within the protocol. Institutions will submit will complete an online questionnaire about their IGRT procedures. Boney anatomy requirements will include submission of data from 2 sequential fraction of both a patient aligned with boney anatomy and pelvic patient. Soft tissue will require similar submissions for a patient aligned using soft tissue and a pelvic patient. Institutions will only be required to submit the pelvic patient once. Data should be in DICOM format and includes planning CT set, RT structure set, RT plan file, RT dose file, localization images and spatial registration file (if available). Reviews will be done by IROC-Houston staff who will continue to provide feedback to the sites. Conclusion: This revised IGRT credentialing process will bring consistency, a savings in time and effort for both the IROC Houston QA office and to those institutions wanting to be credentialed to participate in NCTN Trials. Sponsored by NIH/NCI CA10953.
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International Nuclear Information System (INIS)
Ding, K.
2015-01-01
Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities. It is inexpensive, portable and provides good soft tissue contrast. For challenging soft tissue targets such as pancreatic cancer, ultrasound imaging can be used in combination with pre-treatment MRI and/or CT to transfer important anatomical features for target localization at time of treatment. The non-invasive and non-ionizing nature of ultrasound imaging is particularly powerful for intra-fraction localization and monitoring. Recognizing these advantages, efforts are being made to incorporate novel robotic approaches to position and manipulate the ultrasound probe during irradiation. These recent enabling developments hold potential to bring ultrasound imaging to a new level of IGRT applications. However, many challenges, not limited to image registration, robotic deployment, probe interference and image acquisition rate, need to be addressed to realize the full potential of IGRT with ultrasound imaging. Learning Objectives: Understand the benefits and limitations in using ultrasound to augment MRI and/or CT for motion monitoring during radiation therapy delivery. Understanding passive and active robotic approaches to implement ultrasound imaging for intra-fraction monitoring. Understand issues of probe interference with radiotherapy treatment. Understand the critical clinical workflow for effective and reproducible IGRT using ultrasound guidance. The work of X.L. is supported in part by Elekta; J.W. and K.D. is supported in part by a NIH grant R01 CA161613 and by Elekta; D.H. is support in part by a NIH grant R41 CA174089
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Energy Technology Data Exchange (ETDEWEB)
Ding, K. [Johns Hopkins University: Development of Intra-Fraction Soft Tissue Monitoring with Ultrasound Imaging (United States)
2015-06-15
Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities. It is inexpensive, portable and provides good soft tissue contrast. For challenging soft tissue targets such as pancreatic cancer, ultrasound imaging can be used in combination with pre-treatment MRI and/or CT to transfer important anatomical features for target localization at time of treatment. The non-invasive and non-ionizing nature of ultrasound imaging is particularly powerful for intra-fraction localization and monitoring. Recognizing these advantages, efforts are being made to incorporate novel robotic approaches to position and manipulate the ultrasound probe during irradiation. These recent enabling developments hold potential to bring ultrasound imaging to a new level of IGRT applications. However, many challenges, not limited to image registration, robotic deployment, probe interference and image acquisition rate, need to be addressed to realize the full potential of IGRT with ultrasound imaging. Learning Objectives: Understand the benefits and limitations in using ultrasound to augment MRI and/or CT for motion monitoring during radiation therapy delivery. Understanding passive and active robotic approaches to implement ultrasound imaging for intra-fraction monitoring. Understand issues of probe interference with radiotherapy treatment. Understand the critical clinical workflow for effective and reproducible IGRT using ultrasound guidance. The work of X.L. is supported in part by Elekta; J.W. and K.D. is supported in part by a NIH grant R01 CA161613 and by Elekta; D.H. is support in part by a NIH grant R41 CA174089.
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Wooten, H Omar; Green, Olga; Yang, Min; DeWees, Todd; Kashani, Rojano; Olsen, Jeff; Michalski, Jeff; Yang, Deshan; Tanderup, Kari; Hu, Yanle; Li, H Harold; Mutic, Sasa
2015-07-15
This work describes a commercial treatment planning system, its technical features, and its capabilities for creating (60)Co intensity modulated radiation therapy (IMRT) treatment plans for a magnetic resonance image guidance radiation therapy (MR-IGRT) system. The ViewRay treatment planning system (Oakwood Village, OH) was used to create (60)Co IMRT treatment plans for 33 cancer patients with disease in the abdominal, pelvic, thorax, and head and neck regions using physician-specified patient-specific target coverage and organ at risk (OAR) objectives. Backup plans using a third-party linear accelerator (linac)-based planning system were also created. Plans were evaluated by attending physicians and approved for treatment. The (60)Co and linac plans were compared by evaluating conformity numbers (CN) with 100% and 95% of prescription reference doses and heterogeneity indices (HI) for planning target volumes (PTVs) and maximum, mean, and dose-volume histogram (DVH) values for OARs. All (60)Co IMRT plans achieved PTV coverage and OAR sparing that were similar to linac plans. PTV conformity for (60)Co was within 20 Gy. The mean doses for all (60)Co plan OARs were within clinical tolerances. A commercial (60)Co MR-IGRT device can produce highly conformal IMRT treatment plans similar in quality to linac IMRT for a variety of disease sites. Additional work is in progress to evaluate the clinical benefit of other novel features of this MR-IGRT system. Copyright © 2015 Elsevier Inc. All rights reserved.
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International Nuclear Information System (INIS)
Mutic, S; Low, D; Chmielewski, T; Fought, G; Hernandez, M; Kawrakow, I; Sharma, A; Shvartsman, S; Dempsey, J
2016-01-01
Purpose: To describe the design and characteristics of a novel linac-based MRI guided radiation therapy system that addresses RF and magnetic field interference and that can be housed in conventional radiotherapy vaults. Methods: The MR-IGRT system will provide simultaneous MR imaging combined with both simple (3D) and complex (IMRT, SBRT, SRS) techniques. The system is a combination of a) double-donut split solenoidal superconducting 0.345T MRI; and b) a 90 cm isocenter ring-gantry mounted 6MV, flattening filter-free linac coupled with a stacked doubly-focused multileaf collimator with 4 mm resolution. A novel RF shielding and absorption technology was developed to isolate the beam generating RF emissions from the MR, while a novel magnetic shielding sleeve system was developed to place the magnetic field-sensitive components in low-magnetic field regions. The system design produces high spatial resolution radiation beams with state-of-the art radiation dose characteristics and simultaneous MR imaging. Results: Prototype testing with a spectrum analyzer has demonstrated complete elimination of linac RF inside the treatment room. The magnetic field inside of the magnetic shielding was well below the specification, allowing the linear accelerator to operate normally. A novel on-gantry shimming system maintained < 25 ppm magnetic field homogeneity over a 45 cm spherical field of view for all gantry angles. Conclusion: The system design demonstrates the feasibility coupling a state-of-the art linac system with a 0.345T MRI, enabling highly conformal radiation therapy with simultaneous MR image guidance. S. Mutic’s employer (Washington University) has grant with ViewRay; D. Low is former ViewRay scientific advisory board member (ended October 2015); T. Chmielewski, G. Fought, M. Hernandez, I. Kawrakow, A. Sharma, S. Shvartsman, J. Dempsey are employees of ViewRay with stock options (Dempsey has leadership role and Dempsey/Kawrakow have stock).
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Energy Technology Data Exchange (ETDEWEB)
Mutic, S [Washington University School of Medicine, Saint Louis, MO (United States); Low, D [UCLA, Los Angeles, CA (United States); Chmielewski, T; Fought, G; Hernandez, M; Kawrakow, I; Sharma, A; Shvartsman, S; Dempsey, J [ViewRay, Inc., Oakwood Village, OH (United States)
2016-06-15
Purpose: To describe the design and characteristics of a novel linac-based MRI guided radiation therapy system that addresses RF and magnetic field interference and that can be housed in conventional radiotherapy vaults. Methods: The MR-IGRT system will provide simultaneous MR imaging combined with both simple (3D) and complex (IMRT, SBRT, SRS) techniques. The system is a combination of a) double-donut split solenoidal superconducting 0.345T MRI; and b) a 90 cm isocenter ring-gantry mounted 6MV, flattening filter-free linac coupled with a stacked doubly-focused multileaf collimator with 4 mm resolution. A novel RF shielding and absorption technology was developed to isolate the beam generating RF emissions from the MR, while a novel magnetic shielding sleeve system was developed to place the magnetic field-sensitive components in low-magnetic field regions. The system design produces high spatial resolution radiation beams with state-of-the art radiation dose characteristics and simultaneous MR imaging. Results: Prototype testing with a spectrum analyzer has demonstrated complete elimination of linac RF inside the treatment room. The magnetic field inside of the magnetic shielding was well below the specification, allowing the linear accelerator to operate normally. A novel on-gantry shimming system maintained < 25 ppm magnetic field homogeneity over a 45 cm spherical field of view for all gantry angles. Conclusion: The system design demonstrates the feasibility coupling a state-of-the art linac system with a 0.345T MRI, enabling highly conformal radiation therapy with simultaneous MR image guidance. S. Mutic’s employer (Washington University) has grant with ViewRay; D. Low is former ViewRay scientific advisory board member (ended October 2015); T. Chmielewski, G. Fought, M. Hernandez, I. Kawrakow, A. Sharma, S. Shvartsman, J. Dempsey are employees of ViewRay with stock options (Dempsey has leadership role and Dempsey/Kawrakow have stock).
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Optimization-based reconstruction for reduction of CBCT artifact in IGRT
Xia, Dan; Zhang, Zheng; Paysan, Pascal; Seghers, Dieter; Brehm, Marcus; Munro, Peter; Sidky, Emil Y.; Pelizzari, Charles; Pan, Xiaochuan
2016-04-01
Kilo-voltage cone-beam computed tomography (CBCT) plays an important role in image guided radiation therapy (IGRT) by providing 3D spatial information of tumor potentially useful for optimizing treatment planning. In current IGRT CBCT system, reconstructed images obtained with analytic algorithms, such as FDK algorithm and its variants, may contain artifacts. In an attempt to compensate for the artifacts, we investigate optimization-based reconstruction algorithms such as the ASD-POCS algorithm for potentially reducing arti- facts in IGRT CBCT images. In this study, using data acquired with a physical phantom and a patient subject, we demonstrate that the ASD-POCS reconstruction can significantly reduce artifacts observed in clinical re- constructions. Moreover, patient images reconstructed by use of the ASD-POCS algorithm indicate a contrast level of soft-tissue improved over that of the clinical reconstruction. We have also performed reconstructions from sparse-view data, and observe that, for current clinical imaging conditions, ASD-POCS reconstructions from data collected at one half of the current clinical projection views appear to show image quality, in terms of spatial and soft-tissue-contrast resolution, higher than that of the corresponding clinical reconstructions.
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Middleton, Mark; Frantzis, Jim; Healy, Brendan; Jones, Mark; Murry, Rebecca; Kron, Tomas; Plank, Ashley; Catton, Charles; Martin, Jarad
2011-12-01
The quality assurance (QA) of image-guided radiation therapy (IGRT) within clinical trials is in its infancy, but its importance will continue to grow as IGRT becomes the standard of care. The purpose of this study was to demonstrate the feasibility of IGRT QA as part of the credentialing process for a clinical trial. As part of the accreditation process for a randomized trial in prostate cancer hypofraction, IGRT benchmarking across multiple sites was incorporated. Each participating site underwent IGRT credentialing via a site visit. In all centers, intraprostatic fiducials were used. A real-time assessment of analysis of IGRT was performed using Varian's Offline Review image analysis package. Two-dimensional (2D) kV and MV electronic portal imaging prostate patient datasets were used, consisting of 39 treatment verification images for 2D/2D comparison with the digitally reconstructed radiograph derived from the planning scan. The influence of differing sites, image modality, and observer experience on IGRT was then assessed. Statistical analysis of the mean mismatch errors showed that IGRT analysis was performed uniformly regardless of institution, therapist seniority, or imaging modality across the three orthogonal planes. The IGRT component of clinical trials that include sophisticated planning and treatment protocols must undergo stringent QA. The IGRT technique of intraprostatic fiducials has been shown in the context of this trial to be undertaken in a uniform manner across Australia. Extending this concept to many sites with different equipment and IGRT experience will require a robust remote credentialing process. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.
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International Nuclear Information System (INIS)
Singh, Jasmeet; Greer, Peter B.; White, Martin A.; Parker, Joel; Patterson, Jackie; Tang, Colin I.; Capp, Anne; Wratten, Christopher; Denham, James W.
2013-01-01
Purpose: To estimate the prevalence of rectal and urinary dysfunctional symptoms using image guided radiation therapy (IGRT) with fiducials and magnetic resonance planning for prostate cancer. Methods and Materials: During the implementation stages of IGRT between September 2008 and March 2010, 367 consecutive patients were treated with prostatic irradiation using 3-dimensional conformal radiation therapy with and without IGRT (non-IGRT). In November 2010, these men were asked to report their bowel and bladder symptoms using a postal questionnaire. The proportions of patients with moderate to severe symptoms in these groups were compared using logistic regression models adjusted for tumor and treatment characteristic variables. Results: Of the 282 respondents, the 154 selected for IGRT had higher stage tumors, received higher prescribed doses, and had larger volumes of rectum receiving high dosage than did the 128 selected for non-IGRT. The follow-up duration was 8 to 26 months. Compared with the non-IGRT group, improvement was noted in all dysfunctional rectal symptoms using IGRT. In multivariable analyses, IGRT improved rectal pain (odds ratio [OR] 0.07 [0.009-0.7], P=.02), urgency (OR 0.27 [0.11-0.63], P=<.01), diarrhea (OR 0.009 [0.02-0.35], P<.01), and change in bowel habits (OR 0.18 [0.06-0.52], P<.010). No correlation was observed between rectal symptom levels and dose-volume histogram data. Urinary dysfunctional symptoms were similar in both treatment groups. Conclusions: In comparison with men selected for non-IGRT, a significant reduction of bowel dysfunctional symptoms was confirmed in men selected for IGRT, even though they had larger volumes of rectum treated to higher doses
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Energy Technology Data Exchange (ETDEWEB)
Ahmed, Faisal [University of Utah School of Medicine, Salt Lake City, UT (United States); Loma Linda University Medical Center, Department of Radiation Oncology, Loma Linda, CA (United States); Sarkar, Vikren; Gaffney, David K.; Salter, Bill [Department of Radiation Oncology, University of Utah, Salt Lake City, UT (United States); Poppe, Matthew M., E-mail: matthew.poppe@hci.utah.edu [Department of Radiation Oncology, University of Utah, Salt Lake City, UT (United States)
2016-10-01
Purpose: To evaluate radiation dose delivered to pelvic lymph nodes, if daily Image Guided Radiation Therapy (IGRT) was implemented with treatment shifts based on the primary site (primary clinical target volume [CTV]). Our secondary goal was to compare dosimetric coverage with patient outcomes. Materials and methods: A total of 10 female patients with gynecologic malignancies were evaluated retrospectively after completion of definitive intensity-modulated radiation therapy (IMRT) to their pelvic lymph nodes and primary tumor site. IGRT consisted of daily kilovoltage computed tomography (CT)-on-rails imaging fused with initial planning scans for position verification. The initial plan was created using Varian's Eclipse treatment planning software. Patients were treated with a median radiation dose of 45 Gy (range: 37.5 to 50 Gy) to the primary volume and 45 Gy (range: 45 to 64.8 Gy) to nodal structures. One IGRT scan per week was randomly selected from each patient's treatment course and re-planned on the Eclipse treatment planning station. CTVs were recreated by fusion on the IGRT image series, and the patient's treatment plan was applied to the new image set to calculate delivered dose. We evaluated the minimum, maximum, and 95% dose coverage for primary and nodal structures. Reconstructed primary tumor volumes were recreated within 4.7% of initial planning volume (0.9% to 8.6%), and reconstructed nodal volumes were recreated to within 2.9% of initial planning volume (0.01% to 5.5%). Results: Dosimetric parameters averaged less than 10% (range: 1% to 9%) of the original planned dose (45 Gy) for primary and nodal volumes on all patients (n = 10). For all patients, ≥99.3% of the primary tumor volume received ≥ 95% the prescribed dose (V95%) and the average minimum dose was 96.1% of the prescribed dose. In evaluating nodal CTV coverage, ≥ 99.8% of the volume received ≥ 95% the prescribed dose and the average minimum dose was 93%. In
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Hauri, Pascal; Hälg, Roger A; Schneider, Uwe
2017-07-01
The use of X-ray imaging in radiation therapy can give a substantial dose to the patient. A Cobalt machine combined with an magnetic resonance imaging (MRI) was recently introduced to clinical work. One positive aspect of using non-ionizing imaging devices is the reduction of the patient exposure. The purpose of this study was to quantify the difference in out-of-field dose to the patient between the image guided radiation therapy (IGRT) treatment applied with a linear accelerator with cone beam CT (CBCT) equipment and a Cobalt machine combined with an MRI. The treatment of a rhabdomyosarcoma in the prostate was planned and irradiated using different modalities and radiation therapy machines. The whole-body dose was measured for a 3D-conformal radiation therapy (3DCRT), an intensity-modulated radiation therapy (IMRT), and a volumetric-modulated arc therapy plan applied with a conventional linear accelerator operated at 6 MV beam energy. Additionally, the dose of an IMRT plan applied with a 60 Co machine combined with an MRI was measured. Furthermore, the dose of one CBCT scan using the linear accelerator's on-board imaging system was determined. The 3D dose measurements were performed in an anthropomorphic phantom containing 168 slots for thermoluminescence dosimeters (TLDs). A combination of LiF:Mg,Ti (TLD100) and LiF:Mg,Cu,P (TLD100H) was used to accurately determine the in- and out-of-field dose. The plans were rescaled to different fractionation schemes (2 Gy, 3 Gy, and 5 Gy fraction dose) and the dose of one CBCT scan was additionally added to the treatment dose per fraction applied with the linear accelerator. The resulting absorbed doses per fraction of the two machines were compared. In the target region, all measured treatment plans presented the same magnitude of dose, while the CBCT dose was a factor of 100 smaller. Close to the planned target volume (PTV), the dose from the 60 Co machine was a factor of two higher compared with the 3DCRT + CBCT dose. Up
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International Nuclear Information System (INIS)
Wooten, H. Omar; Green, Olga; Yang, Min; DeWees, Todd; Kashani, Rojano; Olsen, Jeff; Michalski, Jeff; Yang, Deshan; Tanderup, Kari; Hu, Yanle; Li, H. Harold; Mutic, Sasa
2015-01-01
Purpose: This work describes a commercial treatment planning system, its technical features, and its capabilities for creating 60 Co intensity modulated radiation therapy (IMRT) treatment plans for a magnetic resonance image guidance radiation therapy (MR-IGRT) system. Methods and Materials: The ViewRay treatment planning system (Oakwood Village, OH) was used to create 60 Co IMRT treatment plans for 33 cancer patients with disease in the abdominal, pelvic, thorax, and head and neck regions using physician-specified patient-specific target coverage and organ at risk (OAR) objectives. Backup plans using a third-party linear accelerator (linac)-based planning system were also created. Plans were evaluated by attending physicians and approved for treatment. The 60 Co and linac plans were compared by evaluating conformity numbers (CN) with 100% and 95% of prescription reference doses and heterogeneity indices (HI) for planning target volumes (PTVs) and maximum, mean, and dose-volume histogram (DVH) values for OARs. Results: All 60 Co IMRT plans achieved PTV coverage and OAR sparing that were similar to linac plans. PTV conformity for 60 Co was within <1% and 3% of linac plans for 100% and 95% prescription reference isodoses, respectively, and heterogeneity was on average 4% greater. Comparisons of OAR mean dose showed generally better sparing with linac plans in the low-dose range <20 Gy, but comparable sparing for organs with mean doses >20 Gy. The mean doses for all 60 Co plan OARs were within clinical tolerances. Conclusions: A commercial 60 Co MR-IGRT device can produce highly conformal IMRT treatment plans similar in quality to linac IMRT for a variety of disease sites. Additional work is in progress to evaluate the clinical benefit of other novel features of this MR-IGRT system
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Energy Technology Data Exchange (ETDEWEB)
Mazur, T; Gach, H; Chundury, A; Fischer-Valuck, B; Huang, J; Thomas, M; Green, O [Washington University School of Medicine, St. Louis, MO (United States)
2016-06-15
Purpose: To evaluate the feasibility of real-time, real-anatomy tracking and gating for gastric lymphoma patients treated with magnetic resonance image-guided radiation therapy (MR-IGRT) Methods: Over the last 2 years, 8 patients with gastric lymphoma were treated with 0.3-T, Co-60 MR-IGRT. Post-treatment analysis of real-time cine imaging in the sagittal plane during each patient’s treatment revealed significant motion of the stomach. While this motion was accounted for with generous PTV margins, the system’s capability for real-time, real-anatomy tracking could be used to reduce treatment margins by gating. However, analysis was needed for the feasibility of gating using only the single available sagittal imaging plane. While any plane may be chosen, if the stomach moves differently where it is not being observed, there may potentially be a mistreatment. To that end, imaging with healthy volunteers was done to ascertain stomach motion over 2–4 min by analyzing multiple parallel sagittal and coronal planes 0.75 cm apart. The stomach was contoured on every slice, and the mean displacement between pairs of contour centroids was used to determine the amount of overall motion. Results: The mean displacement of the centroid in the image plane was 4.3 ± 0.7 mm. The greatest observed motion was more medial with respect to the patient, and less motion laterally, which implies that gating on a plane located closer to MRI isocenter will provide the more conservative scenario as it will turn the radiation delivery off when the stomach is observed to move outside a predetermined boundary. Conclusion: The stomach was observed to move relatively uniformly throughout, with maximum extent of motion closer to where most MRI systems have the best spatial integrity (near isocenter). Analysis of possible PTV margins from the healthy volunteer study (coupled with previous patient data on interfraction volumetric stomach deformation) is pending.
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Lipiodol as a Fiducial Marker for Image-Guided Radiation Therapy for Bladder Cancer
Energy Technology Data Exchange (ETDEWEB)
Freilich, Jessica M.; Spiess, Philippe E.; Biagioli, Matthew C.; Fernandez, Daniel C.; Shi, Ellen J.; Hunt, Dylan C.; Gupta, Shilpa; Wilder, Richard B., E-mail: richard.wilder@moffitt.org [Moffitt Cancer Center, Tampa, FL (United States)
2014-03-15
Purpose: To evaluate Lipiodol as a liquid, radio-opaque fiducial marker for image-guided radiation therapy (IGRT) for bladder cancer; Materials and Methods: Between 2011 and 2012, 5 clinical T2a-T3b N0 M0 stage II-III bladder cancer patients were treated with maximal transurethral resection of a bladder tumor (TURBT) and image-guided radiation therapy (IGRT) to 64.8 Gy in 36 fractions ± concurrent weekly cisplatin-based or gemcitabine chemotherapy. Ten to 15mL Lipiodol, using 0.5mL per injection, was injected into bladder submucosa circumferentially around the entire periphery of the tumor bed immediately following maximal TURBT. The authors looked at inter-observer variability regarding the size and location of the tumor bed (CTVboost) on computed tomography scans with versus without Lipiodol. Results: Median follow-up was 18 months. Lipiodol was visible on every orthogonal two-dimensional kV portal image throughout the entire, 7-week course of IGRT. There was a trend towards improved inter-observer agreement on the CTVboost with Lipiodol (p = 0.06). In 2 of 5 patients, the tumor bed based upon Lipiodol extended outside a planning target volume that would have been treated with a radiation boost based upon a cystoscopy report and an enhanced computed tomography (CT) scan for staging. There was no toxicity attributable to Lipiodol: Conclusions: Lipiodol constitutes a safe and effective fiducial marker that an urologist can use to demarcate a tumor bed immediately following maximal TURBT. Lipiodol decreases inter-observer variability in the definition of the extent and location of a tumor bed on a treatment planning CT scan for a radiation boost. (author)
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Lipiodol as a Fiducial Marker for Image-Guided Radiation Therapy for Bladder Cancer
Directory of Open Access Journals (Sweden)
Jessica M. Freilich
2014-04-01
Full Text Available Purpose To evaluate Lipiodol as a liquid, radio-opaque fiducial marker for image-guided radiation therapy (IGRT for bladder cancer.Materials and Methods Between 2011 and 2012, 5 clinical T2a-T3b N0 M0 stage II-III bladder cancer patients were treated with maximal transurethral resection of a bladder tumor (TURBT and image-guided radiation therapy (IGRT to 64.8 Gy in 36 fractions ± concurrent weekly cisplatin-based or gemcitabine chemotherapy. Ten to 15mL Lipiodol, using 0.5mL per injection, was injected into bladder submucosa circumferentially around the entire periphery of the tumor bed immediately following maximal TURBT. The authors looked at inter-observer variability regarding the size and location of the tumor bed (CTVboost on computed tomography scans with versus without Lipiodol.Results Median follow-up was 18 months. Lipiodol was visible on every orthogonal two-dimensional kV portal image throughout the entire, 7-week course of IGRT. There was a trend towards improved inter-observer agreement on the CTVboost with Lipiodol (p = 0.06. In 2 of 5 patients, the tumor bed based upon Lipiodol extended outside a planning target volume that would have been treated with a radiation boost based upon a cystoscopy report and an enhanced computed tomography (CT scan for staging. There was no toxicity attributable to Lipiodol.Conclusions Lipiodol constitutes a safe and effective fiducial marker that an urologist can use to demarcate a tumor bed immediately following maximal TURBT. Lipiodol decreases inter-observer variability in the definition of the extent and location of a tumor bed on a treatment planning CT scan for a radiation boost.
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kV cone-beam CT-based IGRT. A clinical review
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Boda-Heggermann, Judit; Lohr, Frank; Wenz, Frederik [Heidelberg Univ., Univ. Medical Center Mannheim (Germany). Dept. of Radiation Oncology; Flentje, Michael; Guckenberger, Matthias [Univ. Hospital Wuerzburg (Germany). Dept. of Radiation Oncology
2011-05-15
Aims and Methods: Delivery of high radiation doses while simultaneously sparing organs at risk requires advanced imaging for target volume definition, highly conformal dose distributions of intensity modulated radiotherapy (IMRT), and narrow planning target volume (PTV) margins. Three-dimensional image-guided radiotherapy (IGRT) with cone-beam computer tomography (CBCT), which results in more precise target localization, is quickly replacing two-dimensional (2D) IGRT. An overview on the clinical applications of kilovoltage gantry-mounted CBCT systems with emphasis on the most frequently targeted body sites (prostate, lung, head and neck) is provided based on a review of the relevant literature. Alternative imaging methods and their advantages/disadvantages are discussed. Results: IGRT with soft tissue detection improves set-up accuracy and is currently replacing 2D verification and frame-based stereotactic treatments; safety margins are significantly reduced by this IGRT technology. In addition, systematic changes of tumor volume and shape and of the normal tissue can be monitored allowing for adaptation of radiotherapy. IGRT in combination with conformal treatment planning allows for hypofractionated dose escalation, which results in improved rates of local tumor control with low rates of toxicity. Conclusion: CBCT allows for daily pretreatment position verification and online correction of set-up errors which improves the precision of patient repositioning with the possibility of shrinking safety margins, sparing organs at risk, and escalating radiation doses. A trend for better clinical outcome can be observed. (orig.)
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Non-invasive pre-clinical MR imaging of prostate tumor hypoxia for radiation therapy prognosis
Directory of Open Access Journals (Sweden)
Derek White
2014-03-01
Full Text Available Purpose: To investigate the usefulness of Oxygen-Enhanced Magnetic Resonance Imaging (OE-MRI changes in signal intensity related to oxygen challenge for predicting tumor response to radiation therapy.Methods: Dynamic MR signal changes were acquired using Varian 4.7T small animal MR scanner prior to image-guided radiation therapy (IGRT of small (n = 6 and large subcutaneous (n = 5 prostate tumors in adult male rats. An interleaved blood-oxygen level dependent (BOLD and tissue-oxygen level dependent (TOLD data acquisition or (IBT was performed using a baseline of medical air as positive control and using medical oxygen as a breathing challenge. BOLD used a 2-D multi-slice spoiled gradient-echo with multi-echo sequence. TOLD used a 2-D multi-slice spoiled gradient-echo sequence. Voxel changes in signal intensity were determined by a correlation coefficient mapping technique. Irradiation technique planned consisted of 1F × 15 Gy AP/PA or 2F × 7.5 Gy AP/PA to the gross tumor volume (GTV. Tumor growth measurements were recorded over time to assess the response to IGRT.Results: BOLD and TOLD signals variously illustrated positive or negative impulse responses in the tumor ROI due to inhaling medical oxygen. Correlation coefficient mapping demonstrated heterogeneity in tumors after inhaling medical oxygen. BOLD and TOLD signals exhibited increased changes in signal intensities after the first fraction of dose. Multi-fractionation had minimum effect until the second fraction of dose was applied. Tumor growth delays were observed when inhaling medical oxygen during IGRT.Conclusion: OE-MRI is a non-invasive imaging modality that can provide insight to the oxygen status of tumors. Observed increase percent changes in BOLD and TOLD signal intensities after the first fraction of dose suggest tumors experienced reoxygenation. OE-MRI could be used for predicting tumor response to IGRT when using medical oxygen for increasing GTV radiosensitivity, suggesting
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International Nuclear Information System (INIS)
Cormack, Robert A.; Sridhar, Srinivas; Suh, W. Warren; D'Amico, Anthony V.; Makrigiorgos, G. Mike
2010-01-01
Purpose: Implantable devices routinely used for increasing spatial accuracy in modern image-guided radiation treatments (IGRT), such as fiducials or brachytherapy spacers, encompass the potential for in situ release of biologically active drugs, providing an opportunity to enhance the therapeutic ratio. We model this new approach for two types of treatment. Methods and Materials: Radiopaque fiducials used in IGRT, or prostate brachytherapy spacers ('eluters'), were assumed to be loaded with radiosensitizer for in situ drug slow release. An analytic function describing the concentration of radiosensitizer versus distance from eluters, depending on diffusion-elimination properties of the drug in tissue, was developed. Tumor coverage by the drug was modeled for tumors typical of lung stereotactic body radiation therapy treatments for various eluter dimensions and drug properties. Six prostate 125 I brachytherapy cases were analyzed by assuming implantation of drug-loaded spacers. Radiosensitizer-induced subvolume boost was simulated from which biologically effective doses for typical radiosensitizers were calculated in one example. Results: Drug distributions from three-dimensional arrangements of drug eluters versus eluter size and drug properties were tabulated. Four radiosensitizer-loaded fiducials provide adequate radiosensitization for ∼4-cm-diameter lung tumors, thus potentially boosting biologically equivalent doses in centrally located stereotactic body treated lesions. Similarly, multiple drug-loaded spacers provide prostate brachytherapy with flexible shaping of 'biologically equivalent doses' to fit requirements difficult to meet by using radiation alone, e.g., boosting a high-risk region juxtaposed to the urethra while respecting normal tissue tolerance of both the urethra and the rectum. Conclusions: Drug loading of implantable devices routinely used in IGRT provides new opportunities for therapy modulation via biological in situ dose painting.
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Russo, Gregory A., E-mail: gregory.russo@bmc.org [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts (United States); Qureshi, Muhammad M.; Truong, Minh-Tam; Hirsch, Ariel E.; Orlina, Lawrence; Bohrs, Harry; Clancy, Pauline; Willins, John; Kachnic, Lisa A. [Department of Radiation Oncology, Boston Medical Center and Boston University School of Medicine, Boston, Massachusetts (United States)
2012-11-01
Purpose: To determine whether the use of routine image guided radiation therapy (IGRT) using pretreatment on-board imaging (OBI) with orthogonal kilovoltage X-rays reduces treatment delivery errors. Methods and Materials: A retrospective review of documented treatment delivery errors from 2003 to 2009 was performed. Following implementation of IGRT in 2007, patients received daily OBI with orthogonal kV X-rays prior to treatment. The frequency of errors in the pre- and post-IGRT time frames was compared. Treatment errors (TEs) were classified as IGRT-preventable or non-IGRT-preventable. Results: A total of 71,260 treatment fractions were delivered to 2764 patients. A total of 135 (0.19%) TEs occurred in 39 (1.4%) patients (3.2% in 2003, 1.1% in 2004, 2.5% in 2005, 2% in 2006, 0.86% in 2007, 0.24% in 2008, and 0.22% in 2009). In 2007, the TE rate decreased by >50% and has remained low (P = .00007, compared to before 2007). Errors were classified as being potentially preventable with IGRT (e.g., incorrect site, patient, or isocenter) vs. not. No patients had any IGRT-preventable TEs from 2007 to 2009, whereas there were 9 from 2003 to 2006 (1 in 2003, 2 in 2004, 2 in 2005, and 4 in 2006; P = .0058) before the implementation of IGRT. Conclusions: IGRT implementation has a patient safety benefit with a significant reduction in treatment delivery errors. As such, we recommend the use of IGRT in routine practice to complement existing quality assurance measures.
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Relationships between cone beam CT value and physical density in image guided radiation therapy
International Nuclear Information System (INIS)
Jiang Xiaoqin; Bai Sen; Zhong Renming; Tang Zhiquan; Jiang Qinfeng; Li Tao
2007-01-01
Objective: To evaluate the main factors affecting the relationship between physical density and CT value in cone-beam computed tomography(CBCT) for imaging guided radiation therapy(IGRT) by comparing the CT value in the image from cone-beam scanner and from fan-beam (FBCT) scanner of a reference phantom. Methods: A taking-park reference phantom with a set of tissue equivalent inserts was scanned at different energies different fields of view (FOV) for IGRT-CBCT and FBCT. The CT value of every insert was measured and compared. Results: The position of inserts in phantom, the size of phantom, the FOV of scanner and different energies had more effect on the relationships between physical density and the CT value from IGRT-CBCT than those from the normal FBCT. The higher the energy was, the less effect of the position of inserts in phantom, the size of phantom and the FOV of scanner on CT value, and the poorer density contrast was observed. Conclusion: At present, the CT value of IGRT-CBCT is not in the true HU value since the manufacturer has not corrected its number. Therefore, we are not able to use the CT value of CBCT for dose calculation in TPS. (authors)
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International Nuclear Information System (INIS)
Morrow, Natalya V.; Lawton, Colleen A.; Qi, X. Sharon; Li, X. Allen
2012-01-01
Purpose: In image-guided radiation therapy (IGRT), different computed tomography (CT) modalities with varying image quality are being used to correct for interfractional variations in patient set-up and anatomy changes, thereby reducing clinical target volume to the planning target volume (CTV-to-PTV) margins. We explore how CT image quality affects patient repositioning and CTV-to-PTV margins in soft tissue registration-based IGRT for prostate cancer patients. Methods and Materials: Four CT-based IGRT modalities used for prostate RT were considered in this study: MV fan beam CT (MVFBCT) (Tomotherapy), MV cone beam CT (MVCBCT) (MVision; Siemens), kV fan beam CT (kVFBCT) (CTVision, Siemens), and kV cone beam CT (kVCBCT) (Synergy; Elekta). Daily shifts were determined by manual registration to achieve the best soft tissue agreement. Effect of image quality on patient repositioning was determined by statistical analysis of daily shifts for 136 patients (34 per modality). Inter- and intraobserver variability of soft tissue registration was evaluated based on the registration of a representative scan for each CT modality with its corresponding planning scan. Results: Superior image quality with the kVFBCT resulted in reduced uncertainty in soft tissue registration during IGRT compared with other image modalities for IGRT. The largest interobserver variations of soft tissue registration were 1.1 mm, 2.5 mm, 2.6 mm, and 3.2 mm for kVFBCT, kVCBCT, MVFBCT, and MVCBCT, respectively. Conclusions: Image quality adversely affects the reproducibility of soft tissue-based registration for IGRT and necessitates a careful consideration of residual uncertainties in determining different CTV-to-PTV margins for IGRT using different image modalities.
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Morrow, Natalya V.; Lawton, Colleen A. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Qi, X. Sharon [Department of Radiation Oncology, University of Colorado Denver, Denver, Colorado (United States); Li, X. Allen, E-mail: ali@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States)
2012-04-01
Purpose: In image-guided radiation therapy (IGRT), different computed tomography (CT) modalities with varying image quality are being used to correct for interfractional variations in patient set-up and anatomy changes, thereby reducing clinical target volume to the planning target volume (CTV-to-PTV) margins. We explore how CT image quality affects patient repositioning and CTV-to-PTV margins in soft tissue registration-based IGRT for prostate cancer patients. Methods and Materials: Four CT-based IGRT modalities used for prostate RT were considered in this study: MV fan beam CT (MVFBCT) (Tomotherapy), MV cone beam CT (MVCBCT) (MVision; Siemens), kV fan beam CT (kVFBCT) (CTVision, Siemens), and kV cone beam CT (kVCBCT) (Synergy; Elekta). Daily shifts were determined by manual registration to achieve the best soft tissue agreement. Effect of image quality on patient repositioning was determined by statistical analysis of daily shifts for 136 patients (34 per modality). Inter- and intraobserver variability of soft tissue registration was evaluated based on the registration of a representative scan for each CT modality with its corresponding planning scan. Results: Superior image quality with the kVFBCT resulted in reduced uncertainty in soft tissue registration during IGRT compared with other image modalities for IGRT. The largest interobserver variations of soft tissue registration were 1.1 mm, 2.5 mm, 2.6 mm, and 3.2 mm for kVFBCT, kVCBCT, MVFBCT, and MVCBCT, respectively. Conclusions: Image quality adversely affects the reproducibility of soft tissue-based registration for IGRT and necessitates a careful consideration of residual uncertainties in determining different CTV-to-PTV margins for IGRT using different image modalities.
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Is Dose Deformation–Invariance Hypothesis Verified in Prostate IGRT?
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Simon, Antoine, E-mail: antoine.simon@univ-rennes1.fr [INSERM, U1099, 35000 Rennes (France); Laboratoire Traitement du Signal et de l' Image, Université de Rennes 1, 35000 Rennes (France); Le Maitre, Amandine; Nassef, Mohamed; Rigaud, Bastien [INSERM, U1099, 35000 Rennes (France); Laboratoire Traitement du Signal et de l' Image, Université de Rennes 1, 35000 Rennes (France); Castelli, Joël [INSERM, U1099, 35000 Rennes (France); Laboratoire Traitement du Signal et de l' Image, Université de Rennes 1, 35000 Rennes (France); Department of Radiotherapy, Centre Eugène Marquis, 35000 Rennes (France); Acosta, Oscar; Haigron, Pascal [INSERM, U1099, 35000 Rennes (France); Laboratoire Traitement du Signal et de l' Image, Université de Rennes 1, 35000 Rennes (France); Lafond, Caroline; Crevoisier, Renaud de [INSERM, U1099, 35000 Rennes (France); Laboratoire Traitement du Signal et de l' Image, Université de Rennes 1, 35000 Rennes (France); Department of Radiotherapy, Centre Eugène Marquis, 35000 Rennes (France)
2017-03-15
Purpose: To assess dose uncertainties resulting from the dose deformation–invariance hypothesis in prostate cone beam computed tomography (CT)–based image guided radiation therapy (IGRT), namely to evaluate whether rigidly propagated planned dose distribution enables good estimation of fraction dose distributions. Methods and Materials: Twenty patients underwent a CT scan for planning intensity modulated radiation therapy–IGRT delivering 80 Gy to the prostate, followed by weekly CT scans. Two methods were used to obtain the dose distributions on the weekly CT scans: (1) recalculating the dose using the original treatment plan; and (2) rigidly propagating the planned dose distribution. The cumulative doses were then estimated in the organs at risk for each dose distribution by deformable image registration. The differences between recalculated and propagated doses were finally calculated for the fraction and the cumulative dose distributions, by use of per-voxel and dose-volume histogram (DVH) metrics. Results: For the fraction dose, the mean per-voxel absolute dose difference was <1 Gy for 98% and 95% of the fractions for the rectum and bladder, respectively. The maximum dose difference within 1 voxel reached, however, 7.4 Gy in the bladder and 8.0 Gy in the rectum. The mean dose differences were correlated with gas volume for the rectum and patient external contour variations for the bladder. The mean absolute differences for the considered volume receiving greater than or equal to dose x (V{sub x}) of the DVH were between 0.37% and 0.70% for the rectum and between 0.53% and 1.22% for the bladder. For the cumulative dose, the mean differences in the DVH were between 0.23% and 1.11% for the rectum and between 0.55% and 1.66% for the bladder. The largest dose difference was 6.86%, for bladder V{sub 80Gy}. The mean dose differences were <1.1 Gy for the rectum and <1 Gy for the bladder. Conclusions: The deformation–invariance hypothesis was
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International Nuclear Information System (INIS)
Anon.
2012-01-01
The volume includes the abstracts of the contributions and posters of the 18th annual congress of the German Radiation Oncology Society DEGRO 2012. The lectures covered the following topics: Radiation physics, therapy planning; gastrointestinal tumors; radiation biology; stererotactic radiotherapy/breast carcinomas; quality management - life quality; head-neck-tumors/lymphomas; NSCL (non-small cell lung carcinomas); pelvic tumors; brain tumors/pediatric tumors. The poster sessions included the following topics: quality management, recurrent tumor therapy; brachytherapy; breast carcinomas and gynecological tumors; pelvis tumors; brain tumors; stereotactic radiotherapy; head-neck carcinomas; NSCL, proton therapy, supporting therapy; clinical radio-oncology, radiation biology, IGRT/IMRT.
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Giaddui, T; Yu, J; Xiao, Y [Thomas Jefferson University, Philadelphia, PA (United States); Jacobs, P [MIM Software, Inc, Cleavland, Ohio (United States); Manfredi, D; Linnemann, N [IROC Philadelphia, RTQA Center, Philadelphia, PA (United States)
2015-06-15
Purpose: 2D-2D kV image guided radiation therapy (IGRT) credentialing evaluation for clinical trial qualification was historically qualitative through submitting screen captures of the fusion process. However, as quantitative DICOM 2D-2D and 2D-3D image registration tools are implemented in clinical practice for better precision, especially in centers that treat patients with protons, better IGRT credentialing techniques are needed. The aim of this work is to establish methodologies for quantitatively reviewing IGRT submissions based on DICOM 2D-2D and 2D-3D image registration and to test the methodologies in reviewing 2D-2D and 2D-3D IGRT submissions for RTOG/NRG Oncology clinical trials qualifications. Methods: DICOM 2D-2D and 2D-3D automated and manual image registration have been tested using the Harmony tool in MIM software. 2D kV orthogonal portal images are fused with the reference digital reconstructed radiographs (DRR) in the 2D-2D registration while the 2D portal images are fused with DICOM planning CT image in the 2D-3D registration. The Harmony tool allows alignment of the two images used in the registration process and also calculates the required shifts. Shifts calculated using MIM are compared with those submitted by institutions for IGRT credentialing. Reported shifts are considered to be acceptable if differences are less than 3mm. Results: Several tests have been performed on the 2D-2D and 2D-3D registration. The results indicated good agreement between submitted and calculated shifts. A workflow for reviewing these IGRT submissions has been developed and will eventually be used to review IGRT submissions. Conclusion: The IROC Philadelphia RTQA center has developed and tested a new workflow for reviewing DICOM 2D-2D and 2D-3D IGRT credentialing submissions made by different cancer clinical centers, especially proton centers. NRG Center for Innovation in Radiation Oncology (CIRO) and IROC RTQA center continue their collaborative efforts to enhance
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International Nuclear Information System (INIS)
Giaddui, T; Yu, J; Xiao, Y; Jacobs, P; Manfredi, D; Linnemann, N
2015-01-01
Purpose: 2D-2D kV image guided radiation therapy (IGRT) credentialing evaluation for clinical trial qualification was historically qualitative through submitting screen captures of the fusion process. However, as quantitative DICOM 2D-2D and 2D-3D image registration tools are implemented in clinical practice for better precision, especially in centers that treat patients with protons, better IGRT credentialing techniques are needed. The aim of this work is to establish methodologies for quantitatively reviewing IGRT submissions based on DICOM 2D-2D and 2D-3D image registration and to test the methodologies in reviewing 2D-2D and 2D-3D IGRT submissions for RTOG/NRG Oncology clinical trials qualifications. Methods: DICOM 2D-2D and 2D-3D automated and manual image registration have been tested using the Harmony tool in MIM software. 2D kV orthogonal portal images are fused with the reference digital reconstructed radiographs (DRR) in the 2D-2D registration while the 2D portal images are fused with DICOM planning CT image in the 2D-3D registration. The Harmony tool allows alignment of the two images used in the registration process and also calculates the required shifts. Shifts calculated using MIM are compared with those submitted by institutions for IGRT credentialing. Reported shifts are considered to be acceptable if differences are less than 3mm. Results: Several tests have been performed on the 2D-2D and 2D-3D registration. The results indicated good agreement between submitted and calculated shifts. A workflow for reviewing these IGRT submissions has been developed and will eventually be used to review IGRT submissions. Conclusion: The IROC Philadelphia RTQA center has developed and tested a new workflow for reviewing DICOM 2D-2D and 2D-3D IGRT credentialing submissions made by different cancer clinical centers, especially proton centers. NRG Center for Innovation in Radiation Oncology (CIRO) and IROC RTQA center continue their collaborative efforts to enhance
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International Nuclear Information System (INIS)
Lefkopoulos, D.; Ferreira, I.; Isambert, A.; Le Pechoux, C.; Mornex, F.
2007-01-01
These last years, the new irradiation techniques as the conformal 3D radiotherapy and the IMRT are strongly correlated with the technological developments in radiotherapy. The rigorous definition of the target volume and the organs at risk required by these irradiation techniques, imposed the development of various image guided patient positioning and target tracking techniques. The availability of these imaging systems inside the treatment room has lead to the exploration of performing real-time adaptive radiation therapy. In this paper we present the different image guided radiotherapy (IGRT) techniques and the adaptive radiotherapy (ART) approaches. IGRT developments are focused in the following areas: 1) biological imaging for better definition of tumor volume; 2) 4D imaging for modeling the intra-fraction organ motion; 3) on-board imaging system or imaging devices registered to the treatment machines for inter-fraction patient localization; and 4) treatment planning and delivery schemes incorporating the information derived from the new imaging techniques. As this paper is included in the 'Cancer Radiotherapie' special volume dedicated to the lung cancers, in the description of the different IGRT techniques we try to present the lung tumors applications when this is possible. (author)
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Phantom evaluation of a commercially available three modality image guided radiation therapy system
International Nuclear Information System (INIS)
Ploquin, Nicolas; Rangel, Alejandra; Dunscombe, Peter
2008-01-01
The authors describe a detailed evaluation of the capabilities of imaging and image registration systems available with Varian linear accelerators for image guided radiation therapy (IGRT). Specifically, they present modulation transfer function curves for megavoltage planar, kilovoltage (kV) planar, and cone beam computed tomography imaging systems and compare these with conventional computed tomography. While kV planar imaging displayed the highest spatial resolution, all IGRT imaging techniques were assessed as adequate for their intended purpose. They have also characterized the image registration software available for use in conjunction with these imaging systems through a comprehensive phantom study involving translations in three orthogonal directions. All combinations of imaging systems and image registration software were found to be accurate, although the planar kV imaging system with automatic registration was generally superior, with both accuracy and precision of the order of 1 mm, under the conditions tested. Based on their phantom study, the attainable accuracy for rigid body translations using any of the features available with Varian equipment will more likely be limited by the resolution of the couch readouts than by inherent limitations in the imaging systems and image registration software. Overall, the accuracy and precision of currently available IGRT technology exceed published experience with the accuracy and precision of contouring for planning.
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New modalities in radiation therapy for treatment of cancer
International Nuclear Information System (INIS)
Kumar, Deepak
2013-01-01
-RAY used). Stereotactic radiation type of external beam radiation therapy, is focused radiation beam targeting a well-defined tumor, these treatment include gamma knife surgery. Intensity-modulated radiation therapy (IMRT) is an advanced type of high-precision radiation which improves the treatment volume to concave tumor shapes. In 3-dimensional conformal radiation therapy (3DCRT), the profile of each radiation beam is shaped to fit the profile of the target using a multi leaf collimator (MLC) and a variable number of beams. In image-guided radiation therapy (IGRT) or four-dimensional radiation therapy, real time imaging combined with real time adjustment of the therapeutic beams use. Brachytherapy (internal radiation therapy) is an effective treatment for cervical, prostate, breast, and skin cancer and can also be used to treat tumors in many other body sites. Radioisotopes therapy (RIT) is a form of targeted therapy which is used for the treatment of certain specific types of tumors. (author)
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The role of a prone setup in breast radiation therapy
Directory of Open Access Journals (Sweden)
Nelly eHuppert
2011-10-01
Full Text Available Most patients undergoing breast conservation therapy (BCT receive radiotherapy in the supine position. Historically, prone breast irradiation has been advocated for women with large pendulous breasts in order to decrease acute and late toxicities. With the advent of CT planning, the prone technique has become both feasible and reproducible. It was shown to be advantageous not only for women with larger breasts but in most patients since it consistently reduces, if not eliminates, the inclusion of heart and lung within the field. The prone setup has been accepted as the best localizing position for both MRI and stereotactic biopsy, but its adoption has been delayed in radiotherapy. New technological advances including image-modulated radiation therapy (IMRT and image-guided radiation therapy (IGRT have made possible the exploration of accelerated fractionation schemes with a concomitant boost to the tumor bed in the prone position, along with better imaging and verification of reproducibility of patient setup. This review describes some of the available techniques for prone breast radiotherapy and the available experience in their application. The NYU prone breast radiotherapy approach is discussed, including a summary of the results from several prospective trials.
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Multimodality Image Fusion and Planning and Dose Delivery for Radiation Therapy
International Nuclear Information System (INIS)
Saw, Cheng B.; Chen Hungcheng; Beatty, Ron E.; Wagner, Henry
2008-01-01
Image-guided radiation therapy (IGRT) relies on the quality of fused images to yield accurate and reproducible patient setup prior to dose delivery. The registration of 2 image datasets can be characterized as hardware-based or software-based image fusion. Hardware-based image fusion is performed by hybrid scanners that combine 2 distinct medical imaging modalities such as positron emission tomography (PET) and computed tomography (CT) into a single device. In hybrid scanners, the patient maintains the same position during both studies making the fusion of image data sets simple. However, it cannot perform temporal image registration where image datasets are acquired at different times. On the other hand, software-based image fusion technique can merge image datasets taken at different times or with different medical imaging modalities. Software-based image fusion can be performed either manually, using landmarks, or automatically. In the automatic image fusion method, the best fit is evaluated using mutual information coefficient. Manual image fusion is typically performed at dose planning and for patient setup prior to dose delivery for IGRT. The fusion of orthogonal live radiographic images taken prior to dose delivery to digitally reconstructed radiographs will be presented. Although manual image fusion has been routinely used, the use of fiducial markers has shortened the fusion time. Automated image fusion should be possible for IGRT because the image datasets are derived basically from the same imaging modality, resulting in further shortening the fusion time. The advantages and limitations of both hardware-based and software-based image fusion methodologies are discussed
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International Nuclear Information System (INIS)
Lin, T; Ma, C
2014-01-01
Purpose: Image-Guided radiation therapy(IGRT) depends on reliable online patient-specific anatomy information to address random and progressive anatomy changes. Large margins have been suggested to bladder cancer treatment due to large daily bladder anatomy variation. KV Cone beam CT(CBCT) has been used in IGRT localization prevalently; however, its lack of soft tissue contrast makes clinicians hesitate to perform daily soft tissue alignment with CBCT for partial bladder cancer treatment. This study compares the localization uncertainties of bladder cancer IGRT using CTon- Rails(CTOR) and CBCT. Methods: Three T2N0M0 bladder cancer patients (total of 66 Gy to partial bladder alone) were localized daily with either CTOR or CBCT for their entire treatment course. A total of 71 sets of CTOR and 22 sets of CBCT images were acquired and registered with original planning CT scans by radiation therapists and approved by radiation oncologists for the daily treatment. CTOR scanning entailed 2mm slice thickness, 0.98mm axial voxel size, 120kVp and 240mAs. CBCT used a half fan pelvis protocol from Varian OBI system with 2mm slice thickness, 0.98axial voxel size, 125kVp, and 680mAs. Daily localization distribution was compared. Accuracy of CTOR and CBCT on partial bladder alignment was also evaluated by comparing bladder PTV coverage. Results: 1cm all around PTV margins were used in every patient except target superior limit margin to 0mm due to bowel constraint. Daily shifts on CTOR averaged to 0.48, 0.24, 0.19 mms(SI,Lat,AP directions); CBCT averaged to 0.43, 0.09, 0.19 mms(SI,Lat,AP directions). The CTOR daily localization showed superior results of V100% of PTV(102% CTOR vs. 89% CBCT) and bowel(Dmax 69.5Gy vs. 78Gy CBCT). CTOR images showed much higher contrast on bladder PTV alignment. Conclusion: CTOR daily localization for IGRT is more dosimetrically beneficial for partial bladder cancer treatment than kV CBCT localization and provided better soft tissue PTV
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Online Magnetic Resonance Image Guided Adaptive Radiation Therapy: First Clinical Applications
International Nuclear Information System (INIS)
Acharya, Sahaja; Fischer-Valuck, Benjamin W.; Kashani, Rojano; Parikh, Parag; Yang, Deshan; Zhao, Tianyu; Green, Olga; Wooten, Omar; Li, H. Harold; Hu, Yanle; Rodriguez, Vivian; Olsen, Lindsey; Robinson, Clifford; Michalski, Jeff; Mutic, Sasa; Olsen, Jeffrey
2016-01-01
Purpose: To demonstrate the feasibility of online adaptive magnetic resonance (MR) image guided radiation therapy (MR-IGRT) through reporting of our initial clinical experience and workflow considerations. Methods and Materials: The first clinically deployed online adaptive MR-IGRT system consisted of a split 0.35T MR scanner straddling a ring gantry with 3 multileaf collimator-equipped "6"0Co heads. The unit is supported by a Monte Carlo–based treatment planning system that allows real-time adaptive planning with the patient on the table. All patients undergo computed tomography and MR imaging (MRI) simulation for initial treatment planning. A volumetric MRI scan is acquired for each patient at the daily treatment setup. Deformable registration is performed using the planning computed tomography data set, which allows for the transfer of the initial contours and the electron density map to the daily MRI scan. The deformed electron density map is then used to recalculate the original plan on the daily MRI scan for physician evaluation. Recontouring and plan reoptimization are performed when required, and patient-specific quality assurance (QA) is performed using an independent in-house software system. Results: The first online adaptive MR-IGRT treatments consisted of 5 patients with abdominopelvic malignancies. The clinical setting included neoadjuvant colorectal (n=3), unresectable gastric (n=1), and unresectable pheochromocytoma (n=1). Recontouring and reoptimization were deemed necessary for 3 of 5 patients, and the initial plan was deemed sufficient for 2 of the 5 patients. The reasons for plan adaptation included tumor progression or regression and a change in small bowel anatomy. In a subsequently expanded cohort of 170 fractions (20 patients), 52 fractions (30.6%) were reoptimized online, and 92 fractions (54.1%) were treated with an online-adapted or previously adapted plan. The median time for recontouring, reoptimization, and QA was 26
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Online Magnetic Resonance Image Guided Adaptive Radiation Therapy: First Clinical Applications
Energy Technology Data Exchange (ETDEWEB)
Acharya, Sahaja; Fischer-Valuck, Benjamin W.; Kashani, Rojano; Parikh, Parag; Yang, Deshan; Zhao, Tianyu; Green, Olga; Wooten, Omar; Li, H. Harold; Hu, Yanle; Rodriguez, Vivian; Olsen, Lindsey; Robinson, Clifford; Michalski, Jeff; Mutic, Sasa; Olsen, Jeffrey, E-mail: jolsen@radonc.wustl.edu
2016-02-01
Purpose: To demonstrate the feasibility of online adaptive magnetic resonance (MR) image guided radiation therapy (MR-IGRT) through reporting of our initial clinical experience and workflow considerations. Methods and Materials: The first clinically deployed online adaptive MR-IGRT system consisted of a split 0.35T MR scanner straddling a ring gantry with 3 multileaf collimator-equipped {sup 60}Co heads. The unit is supported by a Monte Carlo–based treatment planning system that allows real-time adaptive planning with the patient on the table. All patients undergo computed tomography and MR imaging (MRI) simulation for initial treatment planning. A volumetric MRI scan is acquired for each patient at the daily treatment setup. Deformable registration is performed using the planning computed tomography data set, which allows for the transfer of the initial contours and the electron density map to the daily MRI scan. The deformed electron density map is then used to recalculate the original plan on the daily MRI scan for physician evaluation. Recontouring and plan reoptimization are performed when required, and patient-specific quality assurance (QA) is performed using an independent in-house software system. Results: The first online adaptive MR-IGRT treatments consisted of 5 patients with abdominopelvic malignancies. The clinical setting included neoadjuvant colorectal (n=3), unresectable gastric (n=1), and unresectable pheochromocytoma (n=1). Recontouring and reoptimization were deemed necessary for 3 of 5 patients, and the initial plan was deemed sufficient for 2 of the 5 patients. The reasons for plan adaptation included tumor progression or regression and a change in small bowel anatomy. In a subsequently expanded cohort of 170 fractions (20 patients), 52 fractions (30.6%) were reoptimized online, and 92 fractions (54.1%) were treated with an online-adapted or previously adapted plan. The median time for recontouring, reoptimization, and QA was 26
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Yoo, Boyeol; Son, Kihong; Pua, Rizza; Kim, Jinsung; Solodov, Alexander; Cho, Seungryong
2016-10-01
With the increased use of computed tomography (CT) in clinics, dose reduction is the most important feature people seek when considering new CT techniques or applications. We developed an intensity-weighted region-of-interest (IWROI) imaging method in an exact half-fan geometry to reduce the imaging radiation dose to patients in cone-beam CT (CBCT) for image-guided radiation therapy (IGRT). While dose reduction is highly desirable, preserving the high-quality images of the ROI is also important for target localization in IGRT. An intensity-weighting (IW) filter made of copper was mounted in place of a bowtie filter on the X-ray tube unit of an on-board imager (OBI) system such that the filter can substantially reduce radiation exposure to the outer ROI. In addition to mounting the IW filter, the lead-blade collimation of the OBI was adjusted to produce an exact half-fan scanning geometry for a further reduction of the radiation dose. The chord-based rebinned backprojection-filtration (BPF) algorithm in circular CBCT was implemented for image reconstruction, and a humanoid pelvis phantom was used for the IWROI imaging experiment. The IWROI image of the phantom was successfully reconstructed after beam-quality correction, and it was registered to the reference image within an acceptable level of tolerance. Dosimetric measurements revealed that the dose is reduced by approximately 61% in the inner ROI and by 73% in the outer ROI compared to the conventional bowtie filter-based half-fan scan. The IWROI method substantially reduces the imaging radiation dose and provides reconstructed images with an acceptable level of quality for patient setup and target localization. The proposed half-fan-based IWROI imaging technique can add a valuable option to CBCT in IGRT applications.
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Proton Therapy for Thoracoabdominal Tumors
Sakurai, Hideyuki; Okumura, Toshiyuki; Sugahara, Shinji; Nakayama, Hidetsugu; Tokuuye, Koichi
In advanced-stage disease of certain thoracoabdominal tumors, proton therapy (PT) with concurrent chemotherapy may be an option to reduce side effects. Several technological developments, including a respiratory gating system and implantation of fiducial markers for image guided radiation therapy (IGRT), are necessary for the treatment in thoracoabdominal tumors. In this chapter, the role of PT for tumors of the lung, the esophagus, and liver are discussed.
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Directory of Open Access Journals (Sweden)
Benjamin W. Fischer-Valuck, MD
2017-07-01
Conclusions: MR-IGRT has been successfully implemented in a high-volume radiation clinic and provides unique advantages in the treatment of a variety of malignancies. Additional clinical trials are in development to formally evaluate MR-IGRT in the treatment of multiple disease sites with techniques such as SBRT and ART.
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Investigation of cone-beam CT image quality trade-off for image-guided radiation therapy
Bian, Junguo; Sharp, Gregory C.; Park, Yang-Kyun; Ouyang, Jinsong; Bortfeld, Thomas; El Fakhri, Georges
2016-05-01
It is well-known that projections acquired over an angular range slightly over 180° (so-called short scan) are sufficient for fan-beam reconstruction. However, due to practical imaging conditions (projection data and reconstruction image discretization, physical factors, and data noise), the short-scan reconstructions may have different appearances and properties from the full-scan (scans over 360°) reconstructions. Nevertheless, short-scan configurations have been used in applications such as cone-beam CT (CBCT) for head-neck-cancer image-guided radiation therapy (IGRT) that only requires a small field of view due to the potential reduced imaging time and dose. In this work, we studied the image quality trade-off for full, short, and full/short scan configurations with both conventional filtered-backprojection (FBP) reconstruction and iterative reconstruction algorithms based on total-variation (TV) minimization for head-neck-cancer IGRT. Anthropomorphic and Catphan phantoms were scanned at different exposure levels with a clinical scanner used in IGRT. Both visualization- and numerical-metric-based evaluation studies were performed. The results indicate that the optimal exposure level and number of views are in the middle range for both FBP and TV-based iterative algorithms and the optimization is object-dependent and task-dependent. The optimal view numbers decrease with the total exposure levels for both FBP and TV-based algorithms. The results also indicate there are slight differences between FBP and TV-based iterative algorithms for the image quality trade-off: FBP seems to be more in favor of larger number of views while the TV-based algorithm is more robust to different data conditions (number of views and exposure levels) than the FBP algorithm. The studies can provide a general guideline for image-quality optimization for CBCT used in IGRT and other applications.
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Current and future trends in radiation therapy: towards making it more precise
International Nuclear Information System (INIS)
Swaroop, Rashmi
2012-01-01
Advent of computers and researches during the few last decades contributed various new techniques to radiotherapy. These techniques are to be used in correct proportion for an effective and complete treatment. The intent of prescribing radiation and extent of combining it with other modalities is different in each case. Today the store holds techniques like CT based computerized treatment planning. Advanced dose planning techniques, Immobilization techniques, External photon beam radiation therapy, IGRT, IMRT, BART, Brachytherapy, Systemic Radiation Therapy and still developing Particle beam radiotherapy. Radiations have similar effect on malignant and non-malignant cells. Moreover, different types of tumors respond differently to XRT. High precision radiotherapy requires most effectiveness on cancerous cells and negligible side effects on normal tissues. Development of such a targeted XRT demands proper study and evaluation of each technique and their post treatment effects with respect to tumor type and patient condition. A multidisciplinary and multimodality based approach is required. The study is based on secondary data. It evaluates the mechanisms and draws light over the controversies arising out of XRT. Evaluation of secondary data shows that cure rates have been significantly increased with use of targeted radiotherapy. It increases the absorbed dose by tumor and decreases the side effects. Particle radiotherapy reduces damage to healthy tissue between the charged particle radiation source and the tumor and sets a finite range for tissue damage after the tumor has been reached. There are rigorous procedures in place to minimize the risk of accidental over exposure of radiation therapy to patients. It concludes that radiotherapy is well established and newer techniques can be utilized successfully keeping in mind the cancer type and patient condition. (author)
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An IGRT margin concept for pelvic lymph nodes in high-risk prostate cancer
International Nuclear Information System (INIS)
Groher, M.; Kopp, P.; Deutschmann, H.; Sedlmayer, F.; Wolf, Frank; Drerup, M.
2017-01-01
Gold-marker-based image-guided radiation therapy (IGRT) of the prostate allows to correct for inter- and intrafraction motion and therefore to safely reduce margins for the prostate planning target volume (PTV). However, pelvic PTVs, when coadministered in a single plan (registered to gold markers [GM]), require reassessment of the margin concept since prostate movement is independent from the pelvic bony anatomy to which the lymphatics are usually referenced to. We have therefore revisited prostate translational movement relative to the bony anatomy to obtain adequate margins for the pelvic PTVs compensating mismatch resulting from referencing pelvic target volumes to GMs in the prostate. Prostate movement was analyzed in a set of 28 patients (25 fractions each, totaling in 684 fractions) and the required margins calculated for the pelvic PTVs according to Van Herk's margin formula M = 2.5 Σ + 1.64 (σ ' -σ p ). The overall mean prostate movement relative to bony anatomy was 0.9 ± 3.1, 0.6 ± 3.4, and 0.0 ± 0.7 mm in anterior/posterior (A/P), inferior/superior (I/S) and left/right (L/R) direction, respectively. Calculated margins to compensate for the resulting mismatch to bony anatomy were 9/9/2 mm in A/P, I/S, and L/R direction and 10/11/6 mm if an additional residual error of 2 mm was assumed. GM-based IGRT for pelvic PTVs is feasible if margins are adapted accordingly. Margins could be reduced further if systematic errors which are introduced during the planning CT were eliminated. (orig.) [de
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Energy Technology Data Exchange (ETDEWEB)
Murthy, Vedang, E-mail: vmurthy@actrec.gov.in [Department of Radiation Oncology, Tata Memorial Centre, Parel, Mumbai (India); Masodkar, Renuka; Kalyani, Nikhil; Mahantshetty, Umesh [Department of Radiation Oncology, Tata Memorial Centre, Parel, Mumbai (India); Bakshi, Ganesh; Prakash, Gagan [Department of Surgical Oncology, Tata Memorial Centre, Parel, Mumbai (India); Joshi, Amit; Prabhash, Kumar [Department of Medical Oncology, Tata Memorial Centre, Parel, Mumbai (India); Ghonge, Sujata; Shrivastava, Shyamkishore [Department of Radiation Oncology, Tata Memorial Centre, Parel, Mumbai (India)
2016-01-01
Purpose: The purpose of this study was to assess feasibility, clinical outcomes, and toxicity in patients with bladder cancer treated with adaptive, image guided radiation therapy (IGRT) for bladder preservation as a part of trimodality treatment. The role of dose escalation was also studied. Methods and Materials: Forty-four patients with localized bladder cancer were enrolled in a prospective study. They underwent maximal safe resection of bladder tumor and concurrent platinum-based chemotherapy. Patients with large tumors were offered induction chemotherapy. Radiation therapy planning was done using either 3 (n=34) or 6 (n=10) concentrically grown planning target volumes (PTV). Patients received 64 Gy in 32 fractions to the whole bladder and 55 Gy to the pelvic nodes and, if appropriate, a simultaneous integrated boost to the tumor bed to 68 Gy (equivalent dose for 2-Gy fractions assuming α/β of 10 [EQD2]{sub 10} = 68.7 Gy). Daily megavoltage (MV) imaging helped to choose the most appropriate PTV encompassing bladder for the particular day (using plan-of-the-day approach). Results: Most patients (88%) had T2 disease. Sixteen patients (36%) received neoadjuvant chemotherapy. A majority of the patients (73%) received prophylactic nodal irradiation, whereas 55% of the patients received escalated dose to the tumor bed. With a median follow-up of 30 months, the 3-year locoregional control (LRC), disease-free survival, and overall survival (OS) were 78%, 66%, and 67%, respectively. The bladder preservation rate was 83%. LRC (87% vs 68%, respectively, P=.748) and OS (74% vs 60%, respectively, P=.36) rates were better in patients receiving dose escalation. Instances of acute and late Radiation Therapy Oncology Group (RTOG) grade 3 genitourinary toxicity was seen in 5 (11%) and 2 (4%) patients, respectively. There was no acute or late RTOG grade 3 or higher gastrointestinal toxicity. Conclusions: Adaptive IGRT using plan-of-the-day approach for bladder
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International Nuclear Information System (INIS)
Murthy, Vedang; Masodkar, Renuka; Kalyani, Nikhil; Mahantshetty, Umesh; Bakshi, Ganesh; Prakash, Gagan; Joshi, Amit; Prabhash, Kumar; Ghonge, Sujata; Shrivastava, Shyamkishore
2016-01-01
Purpose: The purpose of this study was to assess feasibility, clinical outcomes, and toxicity in patients with bladder cancer treated with adaptive, image guided radiation therapy (IGRT) for bladder preservation as a part of trimodality treatment. The role of dose escalation was also studied. Methods and Materials: Forty-four patients with localized bladder cancer were enrolled in a prospective study. They underwent maximal safe resection of bladder tumor and concurrent platinum-based chemotherapy. Patients with large tumors were offered induction chemotherapy. Radiation therapy planning was done using either 3 (n=34) or 6 (n=10) concentrically grown planning target volumes (PTV). Patients received 64 Gy in 32 fractions to the whole bladder and 55 Gy to the pelvic nodes and, if appropriate, a simultaneous integrated boost to the tumor bed to 68 Gy (equivalent dose for 2-Gy fractions assuming α/β of 10 [EQD2] 10 = 68.7 Gy). Daily megavoltage (MV) imaging helped to choose the most appropriate PTV encompassing bladder for the particular day (using plan-of-the-day approach). Results: Most patients (88%) had T2 disease. Sixteen patients (36%) received neoadjuvant chemotherapy. A majority of the patients (73%) received prophylactic nodal irradiation, whereas 55% of the patients received escalated dose to the tumor bed. With a median follow-up of 30 months, the 3-year locoregional control (LRC), disease-free survival, and overall survival (OS) were 78%, 66%, and 67%, respectively. The bladder preservation rate was 83%. LRC (87% vs 68%, respectively, P=.748) and OS (74% vs 60%, respectively, P=.36) rates were better in patients receiving dose escalation. Instances of acute and late Radiation Therapy Oncology Group (RTOG) grade 3 genitourinary toxicity was seen in 5 (11%) and 2 (4%) patients, respectively. There was no acute or late RTOG grade 3 or higher gastrointestinal toxicity. Conclusions: Adaptive IGRT using plan-of-the-day approach for bladder preservation
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International Nuclear Information System (INIS)
Yock, Adam D.; Garden, Adam S.; Court, Laurence E.; Beadle, Beth M.; Zhang, Lifei; Dong, Lei
2013-01-01
Purpose: The purpose of this work was to determine the expansions in 6 anatomic directions that produced optimal margins considering nonrigid setup errors and tissue deformation for patients receiving image-guided radiation therapy (IGRT) of the oropharynx. Methods and Materials: For 20 patients who had received IGRT to the head and neck, we deformably registered each patient's daily images acquired with a computed tomography (CT)-on-rails system to his or her planning CT. By use of the resulting vector fields, the positions of volume elements within the clinical target volume (CTV) (target voxels) or within a 1-cm shell surrounding the CTV (normal tissue voxels) on the planning CT were identified on each daily CT. We generated a total of 15,625 margins by dilating the CTV by 1, 2, 3, 4, or 5 mm in the posterior, anterior, lateral, medial, inferior, and superior directions. The optimal margins were those that minimized the relative volume of normal tissue voxels positioned within the margin while satisfying 1 of 4 geometric target coverage criteria and 1 of 3 population criteria. Results: Each pair of geometric target coverage and population criteria resulted in a unique, anisotropic, optimal margin. The optimal margin expansions ranged in magnitude from 1 to 5 mm depending on the anatomic direction of the expansion and on the geometric target coverage and population criteria. Typically, the expansions were largest in the medial direction, were smallest in the lateral direction, and increased with the demand of the criteria. The anisotropic margin resulting from the optimal set of expansions always included less normal tissue than did any isotropic margin that satisfied the same pair of criteria. Conclusions: We demonstrated the potential of anisotropic margins to reduce normal tissue exposure without compromising target coverage in IGRT to the head and neck
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Adaptive prostate IGRT combining online re-optimization and re-positioning: a feasibility study
International Nuclear Information System (INIS)
Li Taoran; Zhu Xiaofeng; Lee, W Robert; Vujaskovic, Zeljko; Yin Fangfang; Wu, Q Jackie; Thongphiew, Danthai
2011-01-01
In prostate radiation therapy, inter-fractional organ motion/deformation has posed significant challenges on reliable daily dose delivery. To correct for this issue, off-line re-optimization and online re-positioning have been used clinically. In this paper, we propose an adaptive images guided radiation therapy (AIGRT) scheme that combines these two correction methods in an anatomy-driven fashion. The AIGRT process first tries to find a best plan for the daily target from a plan pool, which consists of the original CT plan and all previous re-optimized plans. If successful, the selected plan is used for daily treatment with translational shifts. Otherwise, the AIGRT invokes the re-optimization process of the CT plan for the anatomy of the day, which is afterward added to the plan pool as a candidate for future fractions. The AIGRT scheme is evaluated by comparisons with daily re-optimization and online re-positioning techniques based on daily target coverage, organs at risk (OAR) sparing and implementation efficiency. Simulated treatment courses for 18 patients with re-optimization alone, re-positioning alone and AIGRT shows that AIGRT offers reliable daily target coverage that is highly comparable to daily re-optimization and significantly improves from re-positioning. AIGRT is also seen to provide improved OAR sparing compared to re-positioning. Apart from dosimetric benefits, AIGRT in addition offers an efficient scheme to integrate re-optimization to current re-positioning-based IGRT workflow.
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Directory of Open Access Journals (Sweden)
Guang-Pei Chen
2017-10-01
Conclusion: CT image quality can be improved with the IQE protocols created in this study, to provide better soft tissue contrast, which would be beneficial for use in radiation therapy, e.g., for planning data acquisition or for IGRT for hypo-fractionated treatments.
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Feng, Yang; Lawrence, Jessica; Cheng, Kun; Montgomery, Dean; Forrest, Lisa; Mclaren, Duncan B; McLaughlin, Stephen; Argyle, David J; Nailon, William H
2016-01-01
The field of veterinary radiation therapy (RT) has gained substantial momentum in recent decades with significant advances in conformal treatment planning, image-guided radiation therapy (IGRT), and intensity-modulated (IMRT) techniques. At the root of these advancements lie improvements in tumor imaging, image alignment (registration), target volume delineation, and identification of critical structures. Image registration has been widely used to combine information from multimodality images such as computerized tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) to improve the accuracy of radiation delivery and reliably identify tumor-bearing areas. Many different techniques have been applied in image registration. This review provides an overview of medical image registration in RT and its applications in veterinary oncology. A summary of the most commonly used approaches in human and veterinary medicine is presented along with their current use in IGRT and adaptive radiation therapy (ART). It is important to realize that registration does not guarantee that target volumes, such as the gross tumor volume (GTV), are correctly identified on the image being registered, as limitations unique to registration algorithms exist. Research involving novel registration frameworks for automatic segmentation of tumor volumes is ongoing and comparative oncology programs offer a unique opportunity to test the efficacy of proposed algorithms. © 2016 American College of Veterinary Radiology.
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A comparative study of automatic image segmentation algorithms for target tracking in MR‐IGRT
Feng, Yuan; Kawrakow, Iwan; Olsen, Jeff; Parikh, Parag J.; Noel, Camille; Wooten, Omar; Du, Dongsu; Mutic, Sasa
2016-01-01
On‐board magnetic resonance (MR) image guidance during radiation therapy offers the potential for more accurate treatment delivery. To utilize the real‐time image information, a crucial prerequisite is the ability to successfully segment and track regions of interest (ROI). The purpose of this work is to evaluate the performance of different segmentation algorithms using motion images (4 frames per second) acquired using a MR image‐guided radiotherapy (MR‐IGRT) system. Manual contours of the kidney, bladder, duodenum, and a liver tumor by an experienced radiation oncologist were used as the ground truth for performance evaluation. Besides the manual segmentation, images were automatically segmented using thresholding, fuzzy k‐means (FKM), k‐harmonic means (KHM), and reaction‐diffusion level set evolution (RD‐LSE) algorithms, as well as the tissue tracking algorithm provided by the ViewRay treatment planning and delivery system (VR‐TPDS). The performance of the five algorithms was evaluated quantitatively by comparing with the manual segmentation using the Dice coefficient and target registration error (TRE) measured as the distance between the centroid of the manual ROI and the centroid of the automatically segmented ROI. All methods were able to successfully segment the bladder and the kidney, but only FKM, KHM, and VR‐TPDS were able to segment the liver tumor and the duodenum. The performance of the thresholding, FKM, KHM, and RD‐LSE algorithms degraded as the local image contrast decreased, whereas the performance of the VP‐TPDS method was nearly independent of local image contrast due to the reference registration algorithm. For segmenting high‐contrast images (i.e., kidney), the thresholding method provided the best speed (<1 ms) with a satisfying accuracy (Dice=0.95). When the image contrast was low, the VR‐TPDS method had the best automatic contour. Results suggest an image quality determination procedure before segmentation and
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A comparative study of automatic image segmentation algorithms for target tracking in MR-IGRT.
Feng, Yuan; Kawrakow, Iwan; Olsen, Jeff; Parikh, Parag J; Noel, Camille; Wooten, Omar; Du, Dongsu; Mutic, Sasa; Hu, Yanle
2016-03-01
On-board magnetic resonance (MR) image guidance during radiation therapy offers the potential for more accurate treatment delivery. To utilize the real-time image information, a crucial prerequisite is the ability to successfully segment and track regions of interest (ROI). The purpose of this work is to evaluate the performance of different segmentation algorithms using motion images (4 frames per second) acquired using a MR image-guided radiotherapy (MR-IGRT) system. Manual contours of the kidney, bladder, duodenum, and a liver tumor by an experienced radiation oncologist were used as the ground truth for performance evaluation. Besides the manual segmentation, images were automatically segmented using thresholding, fuzzy k-means (FKM), k-harmonic means (KHM), and reaction-diffusion level set evolution (RD-LSE) algorithms, as well as the tissue tracking algorithm provided by the ViewRay treatment planning and delivery system (VR-TPDS). The performance of the five algorithms was evaluated quantitatively by comparing with the manual segmentation using the Dice coefficient and target registration error (TRE) measured as the distance between the centroid of the manual ROI and the centroid of the automatically segmented ROI. All methods were able to successfully segment the bladder and the kidney, but only FKM, KHM, and VR-TPDS were able to segment the liver tumor and the duodenum. The performance of the thresholding, FKM, KHM, and RD-LSE algorithms degraded as the local image contrast decreased, whereas the performance of the VP-TPDS method was nearly independent of local image contrast due to the reference registration algorithm. For segmenting high-contrast images (i.e., kidney), the thresholding method provided the best speed (<1 ms) with a satisfying accuracy (Dice=0.95). When the image contrast was low, the VR-TPDS method had the best automatic contour. Results suggest an image quality determination procedure before segmentation and a combination of different
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Comparison of various online IGRT strategies: The benefits of online treatment plan re-optimization
International Nuclear Information System (INIS)
Schulze, Derek; Liang, Jian; Yan, Di; Zhang Tiezhi
2009-01-01
Purpose: To compare the dosimetric differences of various online IGRT strategies and to predict potential benefits of online re-optimization techniques in prostate cancer radiation treatments. Materials and methods: Nine prostate patients were recruited in this study. Each patient has one treatment planning CT images and 10-treatment day CT images. Five different online IGRT strategies were evaluated which include 3D conformal with bone alignment, 3D conformal re-planning via aperture changes, intensity modulated radiation treatment (IMRT) with bone alignment, IMRT with target alignment and IMRT daily re-optimization. Treatment planning and virtual treatment delivery were performed. The delivered doses were obtained using in-house deformable dose mapping software. The results were analyzed using equivalent uniform dose (EUD). Results: With the same margin, rectum and bladder doses in IMRT plans were about 10% and 5% less than those in CRT plans, respectively. Rectum and bladder doses were reduced as much as 20% if motion margin is reduced by 1 cm. IMRT is more sensitive to organ motion. Large discrepancies of bladder and rectum doses were observed compared to the actual delivered dose with treatment plan predication. The therapeutic ratio can be improved by 14% and 25% for rectum and bladder, respectively, if IMRT online re-planning is employed compared to the IMRT bone alignment approach. The improvement of target alignment approach is similar with 11% and 21% dose reduction to rectum and bladder, respectively. However, underdosing in seminal vesicles was observed on certain patients. Conclusions: Online treatment plan re-optimization may significantly improve therapeutic ratio in prostate cancer treatments mostly due to the reduction of PTV margin. However, for low risk patient with only prostate involved, online target alignment IMRT treatment would achieve similar results as online re-planning. For all IGRT approaches, the delivered organ-at-risk doses may be
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International Nuclear Information System (INIS)
Srinivasan, Kavitha; Mohammadi, Mohammad; Shepherd, Justin
2014-01-01
The use of Cone-beam Computed Tomography (CBCT) in radiotherapy is increasing due to the widespread implementation of kilovoltage systems on the currently available linear accelerators. Cone beam CT acts as an effective Image-Guided Radiotherapy (IGRT) tool for the verification of patient position. It also opens up the possibility of real-time re-optimization of treatment plans for Adaptive Radiotherapy (ART). This paper reviews the most prominent applications of CBCT (linac-mounted) in radiation therapy, focusing on CBCT-based planning and dose calculation studies. This is followed by a concise review of the main issues associated with CBCT, such as imaging artifacts, dose and image quality. It explores how medical physicists and oncologists can best apply CBCT for therapeutic applications
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Current perspectives of radiation therapy. History of radiation therapy
International Nuclear Information System (INIS)
Itami, Jun
2011-01-01
More than 100 years have passed since the discovery of X-Strahlen by Roentgen. The history of radiation therapy has evolved under mutual stimulating relationships of the external beam radiation therapy by X-ray tubes and accelerators, and the internal radiation therapy employing radium and other radionuclides. The currently employed technologies in radiation therapy have its origin already till nineteen sixties and the development of physics and engineering have realized the original concept. (author)
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Expanding the use of real-time electromagnetic tracking in radiation oncology.
Shah, Amish P; Kupelian, Patrick A; Willoughby, Twyla R; Meeks, Sanford L
2011-11-15
In the past 10 years, techniques to improve radiotherapy delivery, such as intensity-modulated radiation therapy (IMRT), image-guided radiation therapy (IGRT) for both inter- and intrafraction tumor localization, and hypofractionated delivery techniques such as stereotactic body radiation therapy (SBRT), have evolved tremendously. This review article focuses on only one part of that evolution, electromagnetic tracking in radiation therapy. Electromagnetic tracking is still a growing technology in radiation oncology and, as such, the clinical applications are limited, the expense is high, and the reimbursement is insufficient to cover these costs. At the same time, current experience with electromagnetic tracking applied to various clinical tumor sites indicates that the potential benefits of electromagnetic tracking could be significant for patients receiving radiation therapy. Daily use of these tracking systems is minimally invasive and delivers no additional ionizing radiation to the patient, and these systems can provide explicit tumor motion data. Although there are a number of technical and fiscal issues that need to be addressed, electromagnetic tracking systems are expected to play a continued role in improving the precision of radiation delivery.
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International Nuclear Information System (INIS)
Cai, B; Rao, Y; Tsien, C; Huang, J; Green, O; Mutic, S; Gach, H; Wen, J; Yablonskiy, D
2016-01-01
Purpose: To implement the Gradient Echo Plural Contrast Imaging(GEPCI) technique in MRI-simulation for radiation therapy and assess the feasibility of using GEPCI images with advanced inhomogeneity correction in MRI-guided radiotherapy for brain treatment. Methods: An optimized multigradient-echo GRE sequence (TR=50ms;TE1=4ms;delta-TE=4ms;flip angle=300,11 Echoes) was developed to generate both structural (T1w and T2*w) and functional MRIs (field and susceptibility maps) from a single acquisition. One healthy subject (Subject1) and one post-surgical brain cancer patient (Subject2) were scanned on a Philips Ingenia 1.5T MRI used for radiation therapy simulation. Another healthy subject (Subject3) was scanned on a 0.35T MRI-guided radiotherapy (MR-IGRT) system (ViewRay). A voxel spread function (VSF) was used to correct the B0 inhomogeneities caused by surgical cavities and edema for Subject2. GEPCI images and standard radiotherapy planning MRIs for this patient were compared focusing the delineation of radiotherapy target region. Results: GEPCI brain images were successfully derived from all three subjects with scan times of <7 minutes. The images derived for Subjects1&2 demonstrated that GEPCI can be applied and combined into radiotherapy MRI simulation. Despite low field, T1-weighted and R2* images were successfully reconstructed for Subject3 and were satisfactory for contour and target delineation. The R2* distribution of grey matter (center=12,FWHM=4.5) and white matter (center=14.6, FWHM=2) demonstrated the feasibility for tissue segmentation and quantification. The voxel spread function(VSF) corrected surgical site related inhomogeneities for Subject2. R2* and quantitative susceptibility map(QSM) images for Subject2 can be used to quantitatively assess the brain structure response to radiation over the treatment course. Conclusion: We implemented the GEPCI technique in MRI-simulation and in MR-IGRT system for radiation therapy. The images demonstrated that it
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Patni, Nidhi; Burela, Nagarjuna; Pasricha, Rajesh; Goyal, Jaishree; Soni, Tej Prakash; Kumar, T Senthil; Natarajan, T
2017-01-01
To achieve the best possible therapeutic ratio using high-precision techniques (image-guided radiation therapy/volumetric modulated arc therapy [IGRT/VMAT]) of external beam radiation therapy in cases of carcinoma cervix using kilovoltage cone-beam computed tomography (kV-CBCT). One hundred and five patients of gynecological malignancies who were treated with IGRT (IGRT/VMAT) were included in the study. CBCT was done once a week for intensity-modulated radiation therapy and daily in IGRT/VMAT. These images were registered with the planning CT scan images and translational errors were applied and recorded. In all, 2078 CBCT images were studied. The margins of planning target volume were calculated from the variations in the setup. The setup variation was 5.8, 10.3, and 5.6 mm in anteroposterior, superoinferior, and mediolateral direction. This allowed adequate dose delivery to the clinical target volume and the sparing of organ at risks. Daily kV-CBCT is a satisfactory method of accurate patient positioning in treating gynecological cancers with high-precision techniques. This resulted in avoiding geographic miss.
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International Nuclear Information System (INIS)
Park, Byoung Suk; Ahn, Jong Ho; Kim, Jong Sik; Song, Ki Won
2014-01-01
Cone Beam Computed Tomography(CBCT) in Image Guided Radiation Therapy(IGRT), Set-up error can be reduced but exposure dose of the patient due to CBCT will increase. Through this study, we are to evaluate by making a scenario with the implementation period of CBCT as every other day. Of prostate cancer patients, 9 patients who got a Intensity Modulated Radiation Therapy(IMRT) with CBCT in IGRT were analyzed. Based on values corrected by analyzing set-up error by using CBCT every day during actual treatment, we created a scenario that conducts CBCT every other day. After applying set-up error values of the day not performing CBCT in the scenario to the treatment planning system(Pinnacle 9.2, Philips, USA) by moving them from the treatment iso-center during actual treatment, we established re-treatment plan under the same conditions as actual treatment. Based on this, the dose distribution of normal organs and Planning Target Volume(PTV) was compared and analyzed. In the scenario that performs CBCT every other day based on set-up error values when conducting CBCT every day, average X-axis : 0.2±0.73 mm , Y-axis : 0.1±0.58 mm , Z-axis : -1.3±1.17 mm difference was shown. This was applied to the treatment planning to establish re-treatment plan and dose distribution was evaluated and as a result, Dmean : -0.17 Gy, D99% : -0.71 Gy of PTV difference was shown in comparison with the result obtained when carrying out CBCT every day. As for normal organs, V66 : 1.55% of rectal wall, V66 : -0.76% of bladder difference was shown. In case of a CBCT perform every other day could reduce exposure dose and additional treatment time. And it is thought to be able to consider the application depending on the condition of the patient because the difference in the dose distribution of normal organs, PTV is not large
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Energy Technology Data Exchange (ETDEWEB)
Tsang, Derek S.; Voncken, Francine E.M.; Tse, Regina V. [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Sykes, Jenna [Department of Biostatistics, Princess Margaret Cancer Centre, University Health Network, Toronto (Canada); Wong, Rebecca K.S.; Dinniwell, Rob E.; Kim, John; Ringash, Jolie; Brierley, James D.; Cummings, Bernard J.; Brade, Anthony [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Dawson, Laura A., E-mail: laura.dawson@rmp.uhn.on.ca [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada)
2013-12-01
Purpose: Reduction of respiratory motion is desirable to reduce the volume of normal tissues irradiated, to improve concordance of planned and delivered doses, and to improve image guided radiation therapy (IGRT). We hypothesized that pretreatment lorazepam would lead to a measurable reduction of liver motion. Methods and Materials: Thirty-three patients receiving upper abdominal IGRT were recruited to a double-blinded randomized controlled crossover trial. Patients were randomized to 1 of 2 study arms: arm 1 received lorazepam 2 mg by mouth on day 1, followed by placebo 4 to 8 days later; arm 2 received placebo on day 1, followed by lorazepam 4 to 8 days later. After tablet ingestion and daily radiation therapy, amplitude of liver motion was measured on both study days. The primary outcomes were reduction in craniocaudal (CC) liver motion using 4-dimensional kV cone beam computed tomography (CBCT) and the proportion of patients with liver motion ≤5 mm. Secondary endpoints included motion measured with cine magnetic resonance imaging and kV fluoroscopy. Results: Mean relative and absolute reduction in CC amplitude with lorazepam was 21% and 2.5 mm respectively (95% confidence interval [CI] 1.1-3.9, P=.001), as assessed with CBCT. Reduction in CC amplitude to ≤5 mm residual liver motion was seen in 13% (95% CI 1%-25%) of patients receiving lorazepam (vs 10% receiving placebo, P=NS); 65% (95% CI 48%-81%) had reduction in residual CC liver motion to ≤10 mm (vs 52% with placebo, P=NS). Patients with large respiratory movement and patients who took lorazepam ≥60 minutes before imaging had greater reductions in liver CC motion. Mean reductions in liver CC amplitude on magnetic resonance imaging and fluoroscopy were nonsignificant. Conclusions: Lorazepam reduces liver motion in the CC direction; however, average magnitude of reduction is small, and most patients have residual motion >5 mm.
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Expanding the use of real‐time electromagnetic tracking in radiation oncology
Kupelian, Patrick A.; Willoughby, Twyla R.; Meeks, Sanford L.
2011-01-01
In the past 10 years, techniques to improve radiotherapy delivery, such as intensity‐modulated radiation therapy (IMRT), image‐guided radiation therapy (IGRT) for both inter‐ and intrafraction tumor localization, and hypofractionated delivery techniques such as stereotactic body radiation therapy (SBRT), have evolved tremendously. This review article focuses on only one part of that evolution, electromagnetic tracking in radiation therapy. Electromagnetic tracking is still a growing technology in radiation oncology and, as such, the clinical applications are limited, the expense is high, and the reimbursement is insufficient to cover these costs. At the same time, current experience with electromagnetic tracking applied to various clinical tumor sites indicates that the potential benefits of electromagnetic tracking could be significant for patients receiving radiation therapy. Daily use of these tracking systems is minimally invasive and delivers no additional ionizing radiation to the patient, and these systems can provide explicit tumor motion data. Although there are a number of technical and fiscal issues that need to be addressed, electromagnetic tracking systems are expected to play a continued role in improving the precision of radiation delivery. PACS number: 87.63.‐d PMID:22089017
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Does IGRT ensure target dose coverage of head and neck IMRT patients?
International Nuclear Information System (INIS)
Graff, Pierre; Hu Weigang; Yom, Sue S.; Pouliot, Jean
2012-01-01
Purpose: To determine if image-guided radiotherapy (IGRT) ensures dose coverage to the target, and to assess the dosimetric impact of anatomic changes using megavoltage cone-beam CT (MVCBCT) for patient positioning during head and neck IMRT. Methods and materials: Forty-eight MVCBCT from 10 head and neck IMRT/IGRT patients were analyzed off-line. Target volumes and organs at risk (OARs) contours delineated on CT were transferred and adjusted on MVCBCT images. Each MVCBCT was processed to allow dose recalculation, resulting in 469 dose–volume histograms (DVHs). The concept of dosimetric latitude was introduced to provide a clinical perspective. Results: MVCBCT target DVHs showed a moderate level of difference in D95 (dose to ⩾95% of volume), generally less than a 5% difference from the planned dose. Delivered-dose increases to the spinal cord and brainstem showed no apparent time trend. The 4 mm margin around OARs was a useful precaution to prevent exceeding critical dose thresholds. The parotid glands showed progressive increases in mean dose related to shrinkage of the external contours. Conclusion: IGRT repositioning ensured target volume coverage, but significant dose variations were observed for OARs. The dosimetric impact of anatomic changes during radiotherapy was of lesser importance than the effects of IGRT repositioning.
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International Nuclear Information System (INIS)
Kang, Soo Man
2008-01-01
To reduce side effects in image guided radiation therapy (IGRT) and to improve the quality of life of patients, also to meet accurate SETUP condition for patients, the various SETUP correction conditions were compared and evaluated by using on board imager (OBI) during the SETUP. Each 30 cases of the head, the neck, the chest, the belly, and the pelvis in 150 cases of IGRT patients was corrected after confirmation by using OBI at every 2-3 day. Also, the difference of the SETUP through the skin-marker and the anatomic SETUP through the OBI was evaluated. General SETUP errors (Transverse, Coronal, Sagittal) through the OBI at original SETUP position were Head and Neck: 1.3 mm, Brain: 2 mm, Chest: 3 mm, Abdoman: 3.7 mm, Pelvis: 4 mm. The patients with more that 3 mm in the error range were observed in the correction devices and the patient motions by confirming in treatment room. Moreover, in the case of female patients, the result came from the position of hairs during the Head and Neck, Brain tumor. Therefore, after another SETUP in each cases of over 3 mm in the error range, the treatment was carried out. Mean error values of each parts estimated after the correction were 1 mm for the head, 1.2 mm for the neck, 2.5 mm for the chest, 2.5 mm for the belly, and 2.6 mm for the pelvis. The result showed the correction of SETUP for each treatment through OBI is extremely difficult because of the importance of SETUP in radiation treatment. However, by establishing the average standard of the patients from this research result, the better patient satisfaction and treatment results could be obtained.
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Energy Technology Data Exchange (ETDEWEB)
Kang, Soo Man [Dept. of Radiation Oncology, Kosin University Gospel Hospital, Busan (Korea, Republic of)
2008-09-15
To reduce side effects in image guided radiation therapy (IGRT) and to improve the quality of life of patients, also to meet accurate SETUP condition for patients, the various SETUP correction conditions were compared and evaluated by using on board imager (OBI) during the SETUP. Each 30 cases of the head, the neck, the chest, the belly, and the pelvis in 150 cases of IGRT patients was corrected after confirmation by using OBI at every 2-3 day. Also, the difference of the SETUP through the skin-marker and the anatomic SETUP through the OBI was evaluated. General SETUP errors (Transverse, Coronal, Sagittal) through the OBI at original SETUP position were Head and Neck: 1.3 mm, Brain: 2 mm, Chest: 3 mm, Abdoman: 3.7 mm, Pelvis: 4 mm. The patients with more that 3 mm in the error range were observed in the correction devices and the patient motions by confirming in treatment room. Moreover, in the case of female patients, the result came from the position of hairs during the Head and Neck, Brain tumor. Therefore, after another SETUP in each cases of over 3 mm in the error range, the treatment was carried out. Mean error values of each parts estimated after the correction were 1 mm for the head, 1.2 mm for the neck, 2.5 mm for the chest, 2.5 mm for the belly, and 2.6 mm for the pelvis. The result showed the correction of SETUP for each treatment through OBI is extremely difficult because of the importance of SETUP in radiation treatment. However, by establishing the average standard of the patients from this research result, the better patient satisfaction and treatment results could be obtained.
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Energy Technology Data Exchange (ETDEWEB)
Montanari, Davide; Scolari, Enrica; Silvestri, Chiara; Graves, Yan Jiang; Cervino, Laura [Center for Advanced Radiotherapy Technologies, University of California San Diego, La Jolla, CA 92037-0843 (United States); Yan, Hao; Jiang, Steve B; Jia, Xun [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9315 (United States); Rice, Roger [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, CA 92037-0843 (United States)
2014-03-07
Cone beam CT (CBCT) has been widely used for patient setup in image-guided radiation therapy (IGRT). Radiation dose from CBCT scans has become a clinical concern. The purposes of this study are (1) to commission a graphics processing unit (GPU)-based Monte Carlo (MC) dose calculation package gCTD for Varian On-Board Imaging (OBI) system and test the calculation accuracy, and (2) to quantitatively evaluate CBCT dose from the OBI system in typical IGRT scan protocols. We first conducted dose measurements in a water phantom. X-ray source model parameters used in gCTD are obtained through a commissioning process. gCTD accuracy is demonstrated by comparing calculations with measurements in water and in CTDI phantoms. Twenty-five brain cancer patients are used to study dose in a standard-dose head protocol, and 25 prostate cancer patients are used to study dose in pelvis protocol and pelvis spotlight protocol. Mean dose to each organ is calculated. Mean dose to 2% voxels that have the highest dose is also computed to quantify the maximum dose. It is found that the mean dose value to an organ varies largely among patients. Moreover, dose distribution is highly non-homogeneous inside an organ. The maximum dose is found to be 1–3 times higher than the mean dose depending on the organ, and is up to eight times higher for the entire body due to the very high dose region in bony structures. High computational efficiency has also been observed in our studies, such that MC dose calculation time is less than 5 min for a typical case. (paper)
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International Nuclear Information System (INIS)
Rodriguez, V; Li, H; Yang, D; Kashani, R; Wooten, H; Mutic, S; Green, O; Dempsey, J
2014-01-01
Purpose: To test the sensitivity of the quality assurance (QA) tools actively used on a clinical MR-IGRT system for potential delivery errors. Methods: Patient-specific QA procedures have been implemented for a commercially available Cobalt-60 MR-IGRT system. The QA tools utilized were a MR-compatible cylindrical diode-array detector (ArcCHECK) with a custom insert which positions an ionization chamber (Exradin A18) in the middle of the device, as well as an in-house treatment delivery verification program. These tools were tested to investigate their sensitivity to delivery errors. For the ArcCHECK and ion chamber, a baseline was established with a static field irradiation to a known dose. Variations of the baseline were investigated which included rotated gantry, altered field size, directional shifts, and different delivery time. In addition, similar variations were tested with the automated delivery verification program that compared the treatment parameters in the machine delivery logs to the ones in the plan. To test the software, a 3-field conformal plan was generated as the baseline. Results: ArcCHECK noted at least a 13% decrease in passing rate from baseline in the following scenarios: gantry rotation of 1 degree from plan, 5mm change in field size, 2mm lateral shift, and delivery time decrease. Ion chamber measurements remained consistent for these variations except for the 5 second decrease in delivery time scenario which resulted in an 8% difference from baseline. The delivery verification software was able to detect and report the simulated errors such as when the gantry was rotated by 0.6 degrees, the beam weighting was changed by a percent, a single multileaf collimator was moved by 1cm, and the dose was changed from 2 to 1.8Gy. Conclusion: The results show that the current tools used for patient specific QA are capable of detecting small errors in RT delivery with presence of magnetic field
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Micro-Mini & Nano-Dosimetry & Innovative Technologies in Radiation Therapy (MMND&ITRO2016)
2017-01-01
The biennial MMND (formerly MMD) - IPCT workshops, founded in collaboration with Memorial Sloan Kettering Cancer Center (MSKCC) in 2001, has become an important international multidisciplinary forum for the discussion of advanced dosimetric technology for radiation therapy quality assurance (QA) and space science, as well as advanced technologies for prostate cancer treatment. In more recent years, the interests of participants and the scope of the workshops have extended far beyond prostate cancer treatment alone to include all aspects of radiation therapy, radiation science and technology. We therefore decided to change the name in 2016 to Innovative Technologies in Radiation Oncology (ITRO). MMND ITRO 2016 was held on 26-31 January, 2016 at the beautiful Wrest Point Hotel in Hobart, Tasmania and attracted an outstanding international faculty and nearly 200 delegates from 18 countries (http://mmnditro2016.com/) The MMND 2016 program continued to cover advanced medical physics aspects of IMRT, IGRT, VMAT, SBRT, MRI LINAC, innovative brachytherapy, and synchrotron MRT. The demand for sophisticated real time and high temporal and spatial resolution (down to the submillimetre scale) dosimetry methods and instrumentation for end-to-end QA for these radiotherapy technologies is increasing. Special attention was paid to the contribution of advanced imaging and the application of nanoscience to the recent improvements in imaging and radiotherapy. The last decade has seen great progress in charged particle therapy technology which has spread throughout the world and attracted strong current interest in Australia. This demands a better understanding of the fundamental aspects of ion interactions with biological tissue and the relative biological effectiveness (RBE) of protons and heavy ions. The further development of computational and experimental micro-and nano-dosimetry for ions has important application in radiobiology based treatment planning and space radiation
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Risk management of radiation therapy. Survey by north Japan radiation therapy oncology group
International Nuclear Information System (INIS)
Aoki, Masahiko; Abe, Yoshinao; Yamada, Shogo; Hareyama, Masato; Nakamura, Ryuji; Sugita, Tadashi; Miyano, Takashi
2004-01-01
A North Japan Radiation Oncology Group (NJRTOG) survey was carried out to disclose the risk management of radiation therapy. During April 2002, we sent questionnaires to radiation therapy facilities in northern Japan. There were 31 replies from 27 facilities. Many incidents and accidents were reported, including old cases. Although 60% of facilities had a risk management manual and/or risk manager, only 20% had risk management manuals for radiation therapy. Eighty five percent of radiation oncologists thought that incidents may be due to a lack of manpower. Ninety percent of radiation oncologists want to know the type of cases happened in other facilities. The risk management system is still insufficient for radiation therapy. We hope that our data will be a great help to develop risk management strategies for radiation therapy for all radiation oncologists in Japan. (author)
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Radiation therapy for digestive tumors
International Nuclear Information System (INIS)
Piedbois, P.; Levy, E.; Thirion, P.; Martin, L.; Calitchi, E.; Otmezguine, Y.; Le Bourgeois, J.P.
1995-01-01
This brief review of radiation therapy of digestive tumors in 1994 seeks to provide practical answers to the most commonly asked questions: What is the place of radiation therapy versus chemotherapy for the treatment of these patients ? What are the approved indications of radiation therapy and which avenues of research are being explored ? Radiation therapy is used in over two-thirds of patients referred to an oncology department for a gastrointestinal tract tumor. The main indications are reviewed: cancer of the rectum and anal canal and, to a lesser extent, cancer of the esophagus and pancreas. The main focuses of current research include radiation therapy-chemotherapy combinations, intraoperative radiation therapy, and radiation therapy of hepatobiliary tumors. (authors). 23 refs., 1 fig
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SU-F-J-176: Development of a Patient-Specific 3D Couplant Pad for Ultrasound IGRT
Energy Technology Data Exchange (ETDEWEB)
Kim, H; Chang, A [Soonchunhyang University Hospital, Seoul (Korea, Republic of); Ye, S [Seoul National University, Seoul (Korea, Republic of)
2016-06-15
Purpose: to overcome the several issues of ultrasound image-guided radiation therapy (US IGRT) such as probe pressure and optical tracking disability by using a patient-specific three-dimensional couplant pad (CP) fabricated by a patient’s skin mold using a 3D printing technique. Methods: A CP was then fabricated by pouring gelatin solution into a fixed-shape container accommodating the patient skin mold fabricated by a 3D printer. A breast phantom was fabricated with the compound of gelatin and agarose and a phantom study was carried out. From four patients who underwent US IGRT, total 486 ultrasound images with and without a CP were acquired before treatment. Effectiveness of the use of the CP was evaluated. Results: The positioning accuracies in the phantom study were 0.9 ± 0.3 mm and 1.3 ± 0.4 mm with and without the CP in 3D vector amplitude, respectively. In the patient study, the use of CP reduced the mean target shift from 4.7 mm to 3.7 mm in 3D vector amplitude and the one standard deviation from 2.2 mm to 1.7 mm. It also improved the image contrast around the treatment target by 10 %. The centroid offset of the target volume affected from the US scanning coverage and the target deformation due to the excessive probe pressure was decreased from 4.4 mm to 2.9 mm due to the use of CP. Its difference among three different users was statistically significant (p=0.020) without the use of CP but not significantly different (p=0.133) with the use of CP. Conclusion: Our patient-specific 3D CP using a mold by 3D printing technique is a promising strategy for improving tracking accuracy, image quality, and inter-observer variation for ultrasound-based image guided radiotherapy. In addition to its conventional advantage of non-invasiveness, US can be more facilitated in radiotherapy by the developed CP.
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SU-F-J-176: Development of a Patient-Specific 3D Couplant Pad for Ultrasound IGRT
International Nuclear Information System (INIS)
Kim, H; Chang, A; Ye, S
2016-01-01
Purpose: to overcome the several issues of ultrasound image-guided radiation therapy (US IGRT) such as probe pressure and optical tracking disability by using a patient-specific three-dimensional couplant pad (CP) fabricated by a patient’s skin mold using a 3D printing technique. Methods: A CP was then fabricated by pouring gelatin solution into a fixed-shape container accommodating the patient skin mold fabricated by a 3D printer. A breast phantom was fabricated with the compound of gelatin and agarose and a phantom study was carried out. From four patients who underwent US IGRT, total 486 ultrasound images with and without a CP were acquired before treatment. Effectiveness of the use of the CP was evaluated. Results: The positioning accuracies in the phantom study were 0.9 ± 0.3 mm and 1.3 ± 0.4 mm with and without the CP in 3D vector amplitude, respectively. In the patient study, the use of CP reduced the mean target shift from 4.7 mm to 3.7 mm in 3D vector amplitude and the one standard deviation from 2.2 mm to 1.7 mm. It also improved the image contrast around the treatment target by 10 %. The centroid offset of the target volume affected from the US scanning coverage and the target deformation due to the excessive probe pressure was decreased from 4.4 mm to 2.9 mm due to the use of CP. Its difference among three different users was statistically significant (p=0.020) without the use of CP but not significantly different (p=0.133) with the use of CP. Conclusion: Our patient-specific 3D CP using a mold by 3D printing technique is a promising strategy for improving tracking accuracy, image quality, and inter-observer variation for ultrasound-based image guided radiotherapy. In addition to its conventional advantage of non-invasiveness, US can be more facilitated in radiotherapy by the developed CP.
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International Nuclear Information System (INIS)
Park, Jong Min; Shin, Kyung Hwan; Wu, Hong-Gyun; Kim, Jung-in; Park, So-Yeon; Kim, Jin Ho; Jeon, Seung Hyuck; Choi, Noorie
2018-01-01
To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm 2 , respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field. (orig.) [de
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A model for predicting lung cancer response to therapy
International Nuclear Information System (INIS)
Seibert, Rebecca M.; Ramsey, Chester R.; Hines, J. Wesley; Kupelian, Patrick A.; Langen, Katja M.; Meeks, Sanford L.; Scaperoth, Daniel D.
2007-01-01
Purpose: Volumetric computed tomography (CT) images acquired by image-guided radiation therapy (IGRT) systems can be used to measure tumor response over the course of treatment. Predictive adaptive therapy is a novel treatment technique that uses volumetric IGRT data to actively predict the future tumor response to therapy during the first few weeks of IGRT treatment. The goal of this study was to develop and test a model for predicting lung tumor response during IGRT treatment using serial megavoltage CT (MVCT). Methods and Materials: Tumor responses were measured for 20 lung cancer lesions in 17 patients that were imaged and treated with helical tomotherapy with doses ranging from 2.0 to 2.5 Gy per fraction. Five patients were treated with concurrent chemotherapy, and 1 patient was treated with neoadjuvant chemotherapy. Tumor response to treatment was retrospectively measured by contouring 480 serial MVCT images acquired before treatment. A nonparametric, memory-based locally weight regression (LWR) model was developed for predicting tumor response using the retrospective tumor response data. This model predicts future tumor volumes and the associated confidence intervals based on limited observations during the first 2 weeks of treatment. The predictive accuracy of the model was tested using a leave-one-out cross-validation technique with the measured tumor responses. Results: The predictive algorithm was used to compare predicted verse-measured tumor volume response for all 20 lesions. The average error for the predictions of the final tumor volume was 12%, with the true volumes always bounded by the 95% confidence interval. The greatest model uncertainty occurred near the middle of the course of treatment, in which the tumor response relationships were more complex, the model has less information, and the predictors were more varied. The optimal days for measuring the tumor response on the MVCT images were on elapsed Days 1, 2, 5, 9, 11, 12, 17, and 18 during
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Dosimetric commissioning of a CBCT system for IGRT purposes
International Nuclear Information System (INIS)
Alfonso, R.; Ascencion, Y.; Castillo, D.; Linares, H.; Argota, R.; Garcia, F.
2015-01-01
During the last few years the use of tomographic imaging systems based on kilo voltage, cone shaped photon beams (kV-CBCT) for ensuring an accurate positioning of patients in radiotherapy treatments has expanded to low income departments, such as those existing in public health systems of low and middle income countries (LMIC). Although several dosimetric studies have been published so far, showing results of collateral dose in patients exposed to kV-CBCT studies for image guidance radiotherapy purposes (IGRT), their main objective is to demonstrate that these doses are significantly lower than the prescribed dose to the target volume and even the dose to organs and healthy tissues. In the actual study a methodology is proposed to reduce the CBCT dose during IGRT procedures for tumor targets located in the thorax region, where motion management is crucial. Criteria for dose optimization, based on image quality indexes and automated positioning accuracy, were implemented. (Author)
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Radiation therapy for prostate cancer
International Nuclear Information System (INIS)
Nakamura, Katsumasa
2001-01-01
In Japan, where the mortality rate of prostate cancer is lower than in Western countries, radical prostatectomy or hormonal therapy has been applied more frequently than radiation therapy. However, the number of patients with prostate cancer has been increasing recently and the importance of radiation therapy has rapidly been recognized. Although there have been no randomized trials, results from several institutions in Western countries suggest that similar results of cancer control are achieved with either radiation therapy or radical prostatectomy. For higher-risk cases, conformal high-dose therapy or adjuvant hormonal therapy is more appropriate. In this article, the results of radiation therapy for prostate cancer were reviewed, with a view to the appropriate choice of therapy in Japan. (author)
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The efficacy of Elekta Synergy image-guided radiotherapy
International Nuclear Information System (INIS)
Takamatsu, Shigeyuki; Takanaka, Tsuyoshi; Kumano, Tomoyasu
2008-01-01
We evaluated the efficacy of Elekta Synergy image-guided radiotherapy (IGRT) system equipped with cone beam CT (CBCT) for high accuracy radiation therapy. In cases set up with body marking who had large set up error could be adjusted by this system within 1 mm error. IGRT with CBCT correction provided precise set up. Elekta Synergy IGRT system is useful for high accuracy set up and will facilitate novel precise radiotherapy techniques. (author)
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Micro-Mini and Nano-Dosimetry and Innovative Technologies in Radiation Therapy (MMND and ITRO2016)
International Nuclear Information System (INIS)
2017-01-01
The biennial MMND (formerly MMD) - IPCT workshops, founded in collaboration with Memorial Sloan Kettering Cancer Center (MSKCC) in 2001, has become an important international multidisciplinary forum for the discussion of advanced dosimetric technology for radiation therapy quality assurance (QA) and space science, as well as advanced technologies for prostate cancer treatment. In more recent years, the interests of participants and the scope of the workshops have extended far beyond prostate cancer treatment alone to include all aspects of radiation therapy, radiation science and technology. We therefore decided to change the name in 2016 to Innovative Technologies in Radiation Oncology (ITRO). MMND ITRO 2016 was held on 26-31 January, 2016 at the beautiful Wrest Point Hotel in Hobart, Tasmania and attracted an outstanding international faculty and nearly 200 delegates from 18 countries (http://mmnditro2016.com/) The MMND 2016 program continued to cover advanced medical physics aspects of IMRT, IGRT, VMAT, SBRT, MRI LINAC, innovative brachytherapy, and synchrotron MRT. The demand for sophisticated real time and high temporal and spatial resolution (down to the submillimetre scale) dosimetry methods and instrumentation for end–to-end QA for these radiotherapy technologies is increasing. Special attention was paid to the contribution of advanced imaging and the application of nanoscience to the recent improvements in imaging and radiotherapy. The last decade has seen great progress in charged particle therapy technology which has spread throughout the world and attracted strong current interest in Australia. This demands a better understanding of the fundamental aspects of ion interactions with biological tissue and the relative biological effectiveness (RBE) of protons and heavy ions. The further development of computational and experimental micro-and nano-dosimetry for ions has important application in radiobiology based treatment planning and space radiation
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International Nuclear Information System (INIS)
Bader, J.L.; Glatstein, E.
1987-01-01
The radiation oncologist encounters the critically ill immunosuppressed patient in four settings. First, the newly diagnosed cancer patient presents for initial evaluation and treatment, with immunosuppression from the cancer itself, malnutrition, concomitant infectious disease, prior drug or alcohol abuse or other medical problems. Second, the previously treated cancer patient presents with metastatic or recurrent primary cancer causing local symptoms. Immune dysfunction in this setting may be due to prior chemotherapy and/or radiation as well as any of the original factors. Third, the patient previously treated with radiation presents with a life-threatening problem possibly due to complications of prior therapy. In this setting, the radiation oncologist is asked to evaluate the clinical problem and to suggest whether radiation might be causing part or all of the problem and what can be done to treat these sequelae of radiation. Fourth, the patient with a benign diagnosis (not cancer) is seen with a problem potentially emeliorated by radiation (e.g., kidney transplant rejection, preparation for transplant, or intractable rheumatoid arthritis). This chapter reviews these four issues and presents clinical and radiobiologic principles on which recommendations for therapy are based
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Radiation therapy in old patients. Side effects and results of radiation therapy in old patients
International Nuclear Information System (INIS)
Geinitz, H.; Zimmermann, F.B.; Molls, M.
1999-01-01
Background: Despite a growing number of elderly patients receiving radiation therapy little is known about side effects and outcome of irradiation in this section of the population. Methods: In a review article epidemiologic data, aspects of radiation-biology as well as side effects and outcome of radiation therapy of elderly patients are discussed. Results: Cancer incidence rises with age and is exceeding 3.5% for males older than 85 years. With a life expectancy of more than 4 years, curative therapy is indicated even at this age. Furthermore, several retrospective studies indicate that local control and disease-Specific survival after radiation therapy of elderly patients is comparable with that of younger persons. The exception contains elderly patients with grade-III to IV gliomas or with rectal carcinoma who show a reduced survival which is perhaps caused by less aggressive combined treatment (tumor resection). Although some biological and molecular data indicate a rise in radiation sensitivity with growing age like the reduction of the capacity of some DNA-repair enzymes, there is no convincing evidence in animal studies or in retrospective clinical studies that radiation therapy is generally less well tolerated by older individuals. Some age-depending differences in organ toxicities are described in 3 large studies, which evaluate the data of patients who were enrolled in different EORTC-trials: Older patients suffer more of functional mucositis in case of radiation therapy to the head and neck, they have an increased weight loss and a higher frequency of late esophageal damage when irradiated in the thorax, and they show a higher prevalence of sexual dysfunction when treated with radiation therapy to the pelvis. On the other hand younger patients suffer more from acute toxicity like skin damage, nausea, and deterioration of the performance status during pelvic radiotherapy. When discussing the dose intensity of radiation therapy concomitant disease which
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An IGRT margin concept for pelvic lymph nodes in high-risk prostate cancer
Energy Technology Data Exchange (ETDEWEB)
Groher, M.; Kopp, P.; Deutschmann, H.; Sedlmayer, F.; Wolf, Frank [Paracelsus Medical University of Salzburg, Department of Radiation Oncology, St. Johanns-Spital, Salzburg (Austria); Drerup, M. [Paracelsus Medical University of Salzburg, Department of Urology, St. Johanns-Spital, Salzburg (Austria)
2017-09-15
Gold-marker-based image-guided radiation therapy (IGRT) of the prostate allows to correct for inter- and intrafraction motion and therefore to safely reduce margins for the prostate planning target volume (PTV). However, pelvic PTVs, when coadministered in a single plan (registered to gold markers [GM]), require reassessment of the margin concept since prostate movement is independent from the pelvic bony anatomy to which the lymphatics are usually referenced to. We have therefore revisited prostate translational movement relative to the bony anatomy to obtain adequate margins for the pelvic PTVs compensating mismatch resulting from referencing pelvic target volumes to GMs in the prostate. Prostate movement was analyzed in a set of 28 patients (25 fractions each, totaling in 684 fractions) and the required margins calculated for the pelvic PTVs according to Van Herk's margin formula M = 2.5 Σ + 1.64 (σ{sup '}-σ{sub p}). The overall mean prostate movement relative to bony anatomy was 0.9 ± 3.1, 0.6 ± 3.4, and 0.0 ± 0.7 mm in anterior/posterior (A/P), inferior/superior (I/S) and left/right (L/R) direction, respectively. Calculated margins to compensate for the resulting mismatch to bony anatomy were 9/9/2 mm in A/P, I/S, and L/R direction and 10/11/6 mm if an additional residual error of 2 mm was assumed. GM-based IGRT for pelvic PTVs is feasible if margins are adapted accordingly. Margins could be reduced further if systematic errors which are introduced during the planning CT were eliminated. (orig.) [German] Eine Goldmarker-(GM-)basierte, bildgefuehrte Radiotherapie der Prostata ermoeglicht inter- und intrafraktionelle Bewegungen auszugleichen und somit Sicherheitsraender der Planungszielvolumina (PTV) zu minimieren. Dies gilt jedoch nicht fuer Zielvolumina des pelvinen Lymphabflusses, wenn diese im Rahmen eines simultan integrierten Boost-Konzepts im selben Plan verabreicht werden. Da Bewegungen der Prostata und des Lymphabflusses unabhaengig
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International Nuclear Information System (INIS)
Peschel, R.E; Fisher, J.J.
1986-01-01
The new insights and controversies concerning the radiobiological properties of malignant melanoma and how these relate to new clinical approaches are reviewed. The recent clinical experience with large individual fraction sizes is analyzed. The treatment of malignant melanoma in certain specialized sites is also described. An attempt is made to place in perspective the usefulness of radiation therapy in the treatment of this complex disease. Finally, certain new applications for radiation therapy both alone and in combustion with other treatment modalities are proposed that may ultimately prove appropriate for clinical trials
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Chemotherapy and molecular target therapy combined with radiation therapy
International Nuclear Information System (INIS)
Akimoto, Tetsuo
2012-01-01
Combined chemotherapy and radiation therapy has been established as standard treatment approach for locally advanced head and neck cancer, esophageal cancer and so on through randomized clinical trials. However, radiation-related morbidity such as acute toxicity also increased as treatment intensity has increased. In underlining mechanism for enhancement of normal tissue reaction in chemo-radiation therapy, chemotherapy enhanced radiosensitivity of normal tissues in addition to cancer cells. Molecular target-based drugs combined with radiation therapy have been expected as promising approach that makes it possible to achieve cancer-specific enhancement of radiosensitivity, and clinical trials using combined modalities have been performed to evaluate the feasibility and efficacy of this approach. In order to obtain maximum radiotherapeutic gain, a detailed understanding of the mechanism underlying the interaction between radiation and Molecular target-based drugs is indispensable. Among molecular target-based drugs, inhibitors targeting epidermal growth factor receptor (EGFR) and its signal transduction pathways have been vigorously investigated, and mechanisms regarding the radiosensitizing effect have been getting clear. In addition, the results of randomized clinical trials demonstrated that radiation therapy combined with cetuximab resulted in improvement of overall and disease-specific survival rate compared with radiation therapy in locally advanced head and neck cancer. In this review, clinical usefulness of chemo-radiation therapy and potential molecular targets for potentiation of radiation-induced cell killing are summarized. (author)
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Clinical application of image-guided radiotherapy, IGRT (on the Varian OBI platform)
International Nuclear Information System (INIS)
Sorcini, B.; Tilikidis, A.
2006-01-01
Image-guided radiation therapy (IGRT) can be used to measure and correct positional errors for target and critical structures immediately prior to or during treatment delivery. Some of the most recent available methods applied for target localization are: trans-abdominal ultrasound, implanted markers with in room MV or kV X-rays, optical surface tracking systems, implantable electromagnetic markers, in room CT such as kVCT on rail, kilo-voltage or mega-voltage cone-beam CT (CBCT) and helical megavoltage CT. The verification of the accurate treatment position in conjunction with detailed anatomical information before every fraction can be essential for the outcome of the treatment. In this paper we present the on-board imager (OBI, Varian Medical Systems, Palo Alto, CA) that has been in routine clinical use at the Karolinska University Hospital since June 2004. The OBI has been used for on-line set-up correction of prostate patients using internal gold markers. Displacements of these markers can be monitored radiographically during the treatment course and the registered marker shifts act as a surrogate for prostate motion. For this purpose, on-board kV-kV seems to be an ideal system in terms of image quality. The CBCT function of OBI was installed in March 2005 at our department. It focuses on localizing tumors based on internal anatomy, not just on the conventional external marks or tattoos. The CBCT system provides the capacity for soft tissue imaging in the treatment position and real-time radiographic monitoring during treatment delivery. (authors)
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International Nuclear Information System (INIS)
Bridge, Pete; Carmichael, Mary-Ann; Brady, Carole; Dry, Allison
2013-01-01
Undergraduate students studying the Bachelor of Radiation Therapy at Queensland University of Technology (QUT) attend clinical placements in a number of department sites across Queensland. To ensure that the curriculum prepares students for the most common treatments and current techniques in use in these departments, a curriculum matching exercise was performed. A cross-sectional census was performed on a pre-determined “Snapshot” date in 2012. This was undertaken by the clinical education staff in each department who used a standardized proforma to count the number of patients as well as prescription, equipment, and technique data for a list of tumour site categories. This information was combined into aggregate anonymized data. All 12 Queensland radiation therapy clinical sites participated in the Snapshot data collection exercise to produce a comprehensive overview of clinical practice on the chosen day. A total of 59 different tumour sites were treated on the chosen day and as expected the most common treatment sites were prostate and breast, comprising 46% of patients treated. Data analysis also indicated that intensity-modulated radiotherapy (IMRT) use is relatively high with 19.6% of patients receiving IMRT treatment on the chosen day. Both IMRT and image-guided radiotherapy (IGRT) indications matched recommendations from the evidence. The Snapshot method proved to be a feasible and efficient method of gathering useful data to inform curriculum matching. Frequency of IMRT use in Queensland matches or possibly exceeds that indicated in the literature. It is recommended that future repetition of the study be undertaken in order to monitor trends in referral patterns and new technology implementation
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Energy Technology Data Exchange (ETDEWEB)
Bridge, Pete; Carmichael, Mary-Ann [School of Clinical Sciences, Queensland University of Technology, Brisbane, Queensland, 4001 (Australia); Brady, Carole [Radiation Oncology Mater Centre, Raymond Terrace, South Brisbane, Queensland, 4101 (Australia); Dry, Allison [Cancer Care Services Royal Brisbane Women' s Hospital Herston, Brisbane, Queensland, 4029 (Australia); School of Clinical Sciences, Queensland University of Technology, Brisbane, Queensland, 4001 (Australia)
2013-03-15
Undergraduate students studying the Bachelor of Radiation Therapy at Queensland University of Technology (QUT) attend clinical placements in a number of department sites across Queensland. To ensure that the curriculum prepares students for the most common treatments and current techniques in use in these departments, a curriculum matching exercise was performed. A cross-sectional census was performed on a pre-determined “Snapshot” date in 2012. This was undertaken by the clinical education staff in each department who used a standardized proforma to count the number of patients as well as prescription, equipment, and technique data for a list of tumour site categories. This information was combined into aggregate anonymized data. All 12 Queensland radiation therapy clinical sites participated in the Snapshot data collection exercise to produce a comprehensive overview of clinical practice on the chosen day. A total of 59 different tumour sites were treated on the chosen day and as expected the most common treatment sites were prostate and breast, comprising 46% of patients treated. Data analysis also indicated that intensity-modulated radiotherapy (IMRT) use is relatively high with 19.6% of patients receiving IMRT treatment on the chosen day. Both IMRT and image-guided radiotherapy (IGRT) indications matched recommendations from the evidence. The Snapshot method proved to be a feasible and efficient method of gathering useful data to inform curriculum matching. Frequency of IMRT use in Queensland matches or possibly exceeds that indicated in the literature. It is recommended that future repetition of the study be undertaken in order to monitor trends in referral patterns and new technology implementation.
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Study on external beam radiation therapy
International Nuclear Information System (INIS)
Kim, Mi Sook; Yoo, Seoung Yul; Yoo, Hyung Jun; Ji, Young Hoon; Lee, Dong Han; Lee, Dong Hoon; Choi, Mun Sik; Yoo, Dae Heon; Lee, Hyo Nam; Kim, Kyeoung Jung
1999-04-01
To develop the therapy technique which promote accuracy and convenience in external radiation therapy, to obtain the development of clinical treatment methods for the global competition. The contents of the R and D were 1. structure, process and outcome analysis in radiation therapy department. 2. Development of multimodality treatment in radiation therapy 3. Development of computation using networking techniques 4. Development of quality assurance (QA) system in radiation therapy 5. Development of radiotherapy tools 6. Development of intraoperative radiation therapy (IORT) tools. The results of the R and D were 1. completion of survey and analysis about Korea radiation therapy status 2. Performing QA analysis about ICR on cervix cancer 3. Trial of multicenter randomized study on lung cancers 4. Setting up inter-departmental LAN using MS NT server and Notes program 5. Development of ionization chamber and dose-rate meter for QA in linear accelerator 6. Development on optimized radiation distribution algorithm for multiple slice 7. Implementation on 3 dimensional volume surface algorithm and 8. Implementation on adaptor and cone for IORT
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Study on external beam radiation therapy
Energy Technology Data Exchange (ETDEWEB)
Kim, Mi Sook; Yoo, Seoung Yul; Yoo, Hyung Jun; Ji, Young Hoon; Lee, Dong Han; Lee, Dong Hoon; Choi, Mun Sik; Yoo, Dae Heon; Lee, Hyo Nam; Kim, Kyeoung Jung
1999-04-01
To develop the therapy technique which promote accuracy and convenience in external radiation therapy, to obtain the development of clinical treatment methods for the global competition. The contents of the R and D were 1. structure, process and outcome analysis in radiation therapy department. 2. Development of multimodality treatment in radiation therapy 3. Development of computation using networking techniques 4. Development of quality assurance (QA) system in radiation therapy 5. Development of radiotherapy tools 6. Development of intraoperative radiation therapy (IORT) tools. The results of the R and D were 1. completion of survey and analysis about Korea radiation therapy status 2. Performing QA analysis about ICR on cervix cancer 3. Trial of multicenter randomized study on lung cancers 4. Setting up inter-departmental LAN using MS NT server and Notes program 5. Development of ionization chamber and dose-rate meter for QA in linear accelerator 6. Development on optimized radiation distribution algorithm for multiple slice 7. Implementation on 3 dimensional volume surface algorithm and 8. Implementation on adaptor and cone for IORT.
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Radiation therapy for operable rectal cancer
International Nuclear Information System (INIS)
Bondar, G.V.; Semikoz, N.G.; Bashejev, V.Kh.; Borota, O.V.; Bondarenko, M.V.; Kiyashko, O.Yu.
2012-01-01
The authors present a review of the literature on modern tendencies of radiation therapy application to treatment of operable rectal cancer. Many randomized control studies compared the efficacy of combination of radiation therapy (pre-operative or post-operative) and surgery versus surgery only demonstrating various results. Meta-analysis of the data on efficacy of combination of radiation therapy and standard surgery revealed 22 randomized control studies (14 with pre-operative radiation therapy and 8 with post-operative radiation therapy) with total number of 8507 patients (Colorectal Cancer Collaborative Group, 2000). The use of combination treatment reduced the number of isolated locoregional relapses both with pre-operative (22.5 - 12.5 %; p < 0.00001) and post-operative radiation therapy (25.8 - 16.7 %; p - 0.00001). The influence on total survival was not significant (62 % vs. 63 %; p - 0.06).
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Energy Technology Data Exchange (ETDEWEB)
Son, K; Lee, H; Kim, C; Cho, S [KAIST, Daejeon (Korea, Republic of); Kim, J [Yonsei Cancer Center, Seoul (Korea, Republic of)
2016-06-15
Purpose: To reduce radiation dose to the patients, tube current modulation (TCM) method has been actively used in diagnostic CT systems. However, TCM method has not yet been applied to a kV-CBCT system on a LINAC machine. The purpose of this study is to investigate whether the use of TCM method is desirable in kV-CBCT system for IGRT. We have developed an attenuation-based tube current modulation (a-TCM) method using the prior knowledge of treatment CT image of a patient. Methods: Patients go through a diagnostic CT scan for RT planning; therefore, using this prior information of CT images, one can estimate the total attenuation of an x-ray through the patient body in a CBCT setting for radiation therapy. We performed a numerical study incorporating major factors into account such as polychromatic x-ray, scatter, noise, and bow-tie filter to demonstrate that a-TCM method can produce equivalent quality of images at reduced imaging radiation doses. Using the CT projector program, 680 projection images of the pediatric XCAT phantom were obtained both in conventional scanning condition, i.e., without modulating the tube current, and in the proposed a-TCM scanning condition. FDK reconstruction algorithm was used for image reconstruction, and the organ dose due to imaging radiation has been calculated in both cases and compared using GATE/Geant4 simulation toolkit. Results: Reconstructed CT images in the a-TCM method showed similar SSIM values and noise properties to the reference images acquired by the conventional CBCT. In addition, reduction of organ doses ranged from 12% to 27%. Conclusion: We have successfully demonstrated the feasibility and dosimetric merit of the a-TCM method for kV-CBCT, and envision that it can be a useful option of CBCT scanning that provides patient dose reduction without degrading image quality.
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Job satisfaction among radiation therapy educators.
Swafford, Larry G; Legg, Jeffrey S
2007-01-01
Job satisfaction is one of the most consistent variables related to employee retention and is especially relevant considering the shortage of radiation therapists and radiation therapy educators in the United States. To investigate job satisfaction levels among radiation therapy educators certified by the American Registry of Radiologic Technologists and employed in programs accredited by the Joint Review Committee on Education in Radiologic Technology. The long form of the Minnesota Satisfaction Questionnaire (MSQ) was mailed to 158 radiation therapy educators to measure job satisfaction. Overall job satisfaction and subscales were calculated based on MSQ methodology. A total of 90 usable surveys were returned for a 56.9% response rate. With a "general satisfaction" score of 69.64, radiation therapy educators ranked in the lowest 25th percentile of the nondisabled norm scale for job satisfaction. Respondents reported higher degrees of job satisfaction on the moral values, social service and achievement subscales. Lower job satisfaction levels were associated with the company policies and practices, advancement and compensation subscales. Radiation therapy educators report low job satisfaction. Educational institutions must tailor recruitment and retention efforts to better reflect the positive aspects of being a radiation therapy educator. Furthermore, improving retention and recruitment efforts might help offset the current shortages of radiation therapy educators and, ultimately, clinical radiation therapists.
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International Nuclear Information System (INIS)
Sherertz, Tracy; Hoggarth, Mark; Luce, Jason; Block, Alec M.; Nagda, Suneel; Harkenrider, Matthew M.; Emami, Bahman; Roeske, John C.
2014-01-01
Purpose: A prospective feasibility study was conducted to investigate the utility of dual-energy (DE) imaging compared to conventional x-ray imaging for patients undergoing kV-based image guided radiation therapy (IGRT) for lung cancer. Methods and Materials: An institutional review board-approved feasibility study enrolled patients with lung cancer undergoing IGRT and was initiated in September 2011. During daily setup, 2 sequential respiration-gated x-ray images were obtained using an on-board imager. Imaging was composed of 1 standard x-ray image at 120 kVp (1 mAs) and a second image obtained at 60 kVp (4 mAs). Weighted logarithmic subtraction of the 2 images was performed offline to create a soft tissue-selective DE image. Conventional and DE images were evaluated by measuring relative contrast and contrast-to-noise ratios (CNR) and also by comparing spatial localization, using both approaches. Imaging dose was assessed using a calibrated ion chamber. Results: To date, 10 patients with stage IA to IIIA lung cancer were enrolled and 57 DE images were analyzed. DE subtraction resulted in complete suppression of overlying bone in all 57 DE images, with an average improvement in relative contrast of 4.7 ± 3.3 over that of 120 kVp x-ray images (P<.0002). The improvement in relative contrast with DE imaging was seen for both smaller (gross tumor volume [GTV] ≤5 cc) and larger tumors (GTV >5 cc), with average relative contrast improvement ratios of 3.4 ± 4.1 and 5.4 ± 3.6, respectively. Moreover, the GTV was reliably localized in 95% of the DE images versus 74% of the single energy (SE images, (P=.004). Mean skin dose per DE image set was 0.44 ± 0.03 mGy versus 0.43 ± 0.03 mGy, using conventional kV imaging parameters. Conclusions: Initial results of this feasibility study suggest that DE thoracic imaging may enhance tumor localization in lung cancer patients receiving kV-based IGRT without increasing imaging dose
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Energy Technology Data Exchange (ETDEWEB)
Chen Ting; Jabbour, Salma K.; Haffty, Bruce G.; Yue, Ning [Radiation Oncology Department, Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, New Jersey 08901 (United States); Qin Songbing [Department of Radiation Oncology, The First Affiliated Hospital of Soochow University, Suzhou 215006 (China)
2013-04-15
Purpose: The management of thoracic malignancies with radiation therapy is complicated by continuous target motion. In this study, a real time motion analysis approach is proposed to improve the accuracy of patient setup. Methods: For 11 lung cancer patients a long training fluoroscopy was acquired before the first treatment, and multiple short testing fluoroscopies were acquired weekly at the pretreatment patient setup of image guided radiotherapy (IGRT). The data analysis consisted of three steps: first a 4D target motion model was constructed from 4DCT and projected to the training fluoroscopy through deformable registration. Then the manifold learning method was used to construct a 2D subspace based on the target motion (kinetic) and location (static) information in the training fluoroscopy. Thereafter the respiratory phase in the testing fluoroscopy was determined by finding its location in the subspace. Finally, the phase determined testing fluoroscopy was registered to the corresponding 4DCT to derive the pretreatment patient position adjustment for the IGRT. The method was tested on clinical image sets and numerical phantoms. Results: The registration successfully reconstructed the 4D motion model with over 98% volume similarity in 4DCT, and over 95% area similarity in the training fluoroscopy. The machine learning method derived the phase values in over 98% and 93% test images of the phantom and patient images, respectively, with less than 3% phase error. The setup approach achieved an average accumulated setup error less than 1.7 mm in the cranial-caudal direction and less than 1 mm in the transverse plane. All results were validated against the ground truth of manual delineations by an experienced radiation oncologist. The expected total time for the pretreatment setup analysis was less than 10 s. Conclusions: By combining the registration and machine learning, the proposed approach has the potential to improve the accuracy of pretreatment setup for
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International Nuclear Information System (INIS)
Chen Ting; Jabbour, Salma K.; Haffty, Bruce G.; Yue, Ning; Qin Songbing
2013-01-01
Purpose: The management of thoracic malignancies with radiation therapy is complicated by continuous target motion. In this study, a real time motion analysis approach is proposed to improve the accuracy of patient setup. Methods: For 11 lung cancer patients a long training fluoroscopy was acquired before the first treatment, and multiple short testing fluoroscopies were acquired weekly at the pretreatment patient setup of image guided radiotherapy (IGRT). The data analysis consisted of three steps: first a 4D target motion model was constructed from 4DCT and projected to the training fluoroscopy through deformable registration. Then the manifold learning method was used to construct a 2D subspace based on the target motion (kinetic) and location (static) information in the training fluoroscopy. Thereafter the respiratory phase in the testing fluoroscopy was determined by finding its location in the subspace. Finally, the phase determined testing fluoroscopy was registered to the corresponding 4DCT to derive the pretreatment patient position adjustment for the IGRT. The method was tested on clinical image sets and numerical phantoms. Results: The registration successfully reconstructed the 4D motion model with over 98% volume similarity in 4DCT, and over 95% area similarity in the training fluoroscopy. The machine learning method derived the phase values in over 98% and 93% test images of the phantom and patient images, respectively, with less than 3% phase error. The setup approach achieved an average accumulated setup error less than 1.7 mm in the cranial-caudal direction and less than 1 mm in the transverse plane. All results were validated against the ground truth of manual delineations by an experienced radiation oncologist. The expected total time for the pretreatment setup analysis was less than 10 s. Conclusions: By combining the registration and machine learning, the proposed approach has the potential to improve the accuracy of pretreatment setup for
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Park, Jong Min; Shin, Kyung Hwan; Kim, Jung-In; Park, So-Yeon; Jeon, Seung Hyuck; Choi, Noorie; Kim, Jin Ho; Wu, Hong-Gyun
2018-01-01
To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm 2 , respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field.
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Basal cell carcinoma after radiation therapy
International Nuclear Information System (INIS)
Shimbo, Keisuke; Terashi, Hiroto; Ishida, Yasuhisa; Tahara, Shinya; Osaki, Takeo; Nomura, Tadashi; Ejiri, Hirotaka
2008-01-01
We reported two cases of basal cell carcinoma (BCC) that developed after radiation therapy. A 50-year-old woman, who had received an unknown amount of radiation therapy for the treatment of intracranial germinoma at the age of 22, presented with several tumors around the radiation ulcer. All tumors showed BCC. A 33-year-old woman, who had received an unknown amount of radiation therapy on the head for the treatment of leukemia at the age of 2, presented with a black nodule within the area of irradiation. The tumor showed BCC. We discuss the occurrence of BCC after radiation therapy. (author)
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Technical advances in radiation therapy
International Nuclear Information System (INIS)
Sause, W.T.
1986-01-01
Substantial advances have been made in radiation therapy. Many of these advances can be applied in most radiation therapy departments without expensive improvements in equipment. Changes in radiation fractionation, chemotherapeutic sensitization, intraoperative radiation, and interstitial implants can be performed with experience and improved physician training in most medium-sized departments. Advances that require investments in expensive equipment such as particle radiation and hyperthermia will need to be evaluated at designated treatment centers. 106 references
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Radiation therapy sources, equipment and installations
International Nuclear Information System (INIS)
2011-03-01
The safety code for Telegamma Therapy Equipment and Installations, (AERB/SC/MED-1) and safety code for Brachytherapy Sources, Equipment and Installations, (AERB/SC/MED-3) were issued by AERB in 1986 and 1988 respectively. These codes specified mandatory requirements for radiation therapy facilities, covering the entire spectrum of operations ranging from the setting up of a facility to its ultimate decommissioning, including procedures to be followed during emergency situations. The codes also stipulated requirements of personnel and their responsibilities. With the advent of new techniques and equipment such as 3D-conformal radiation therapy, intensity modulated radiation therapy, image guided radiation therapy, treatment planning system, stereotactic radiosurgery, stereotactic radiotherapy, portal imaging, integrated brachytherapy and endovascular brachytherapy during the last two decades, AERB desires that these codes be revised and merged into a single code titled Radiation Therapy Sources, Equipment, and Installations
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Radiation Therapy Side Effects
Radiation therapy has side effects because it not only kills or slows the growth of cancer cells, it can also affect nearby healthy cells. Many people who get radiation therapy experience fatigue. Other side effects depend on the part of the body that is being treated. Learn more about possible side effects.
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Internal Radiation Therapy for Cancer
When getting internal radiation therapy, a source of radiation is put inside your body, in either liquid or solid form. It can be used treat different kinds of cancer, including thyroid, head and neck, breast, cervix, prostate, and eye. Learn more about how what to expect when getting internal radiation therapy.
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Nonsurgical treatment for cancer using radiation therapy
International Nuclear Information System (INIS)
Ogi, Yasuo
2012-01-01
The number of people who are dying from cancer has been increasing in association with population aging. Radiation therapy is now one of the three major cancer treatment methods, along with surgery and chemotherapy. People used to consider radiation therapy only as a ''noninvasive cancer treatment''; however, with the ceaseless effort by medical experts and corporations, different radiation therapy types and techniques including the latest technical advances have come out one after another, and the improvements in radiation therapies have provided treatments that are not only less traumatizing to patients but also as effective and therapeutic as surgery in certain body regions. The importance of radiation therapy has become and will become even greater in the society with more elderly cancer patients who do not have the physical strength to undergo surgery. In this article, the history of radiation therapy, rapidly developed high-precision radiation therapy techniques, and unsolved issues are discussed, and then, ''MHI vero4DRT'', which is the high-precision image-guided radiation therapy equipment developed for solving such issues, is introduced. (author)
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Energy Technology Data Exchange (ETDEWEB)
Sandrini, E.S.; Silveira, T.B.; Vieira, D.S.; Anjos, L.E.A.; Lopez, J.C.C.; Batista, D.V.S., E-mail: emmilyfisica@gmail.com [Instituto Nacional de Cancer Jose de Alencar Gomes da Silva, Rio de Janeiro, RJ (Brazil)
2014-08-15
Clinical radiotherapy procedures aim at high precision. However, there are many errors sources that act during treatment preparation and execution that limit its accuracy. The use of imaged-guided radiotherapy (IGRT) increases the agreement between the planned dose and the actual dose deposited in the target, at the same time allows to evaluate the uncertainties related to the setup and a possible reduction in the planning target volume (PTV) margin. Thus the aim of this study was to determine the best PTV margin to be used in radiotherapy treatment of prostate cancer using intensity modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy (VMAT) techniques associated with IGRT. A total of four patients with prostate daily cone beam computed tomography (CBCT) were analyzed. Systematic and random errors were calculated statistically based on the displacements couch for 128 CBCTs. It was found that a symmetric margin of 0.75 cm from clinical treatment volume (CTV) to PTV is sufficient to encompass the uncertainties inherent to the treatment applying IGRT. Besides without that and maintaining the same tumor control probability, a symmetric margin of 1,24 cm would be necessary. This study showed that using daily image verification the setup errors are reduced, which generates a lower PTV margin. (author)
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Radiation Therapy - Multiple Languages
... W XYZ List of All Topics All Radiation Therapy - Multiple Languages To use the sharing features on this page, ... Information Translations Vietnamese (Tiếng Việt) Expand Section Radiation Therapy - Tiếng Việt (Vietnamese) ... Health Information Translations Characters not displaying correctly on this page? See language display issues . Return to the MedlinePlus Health Information ...
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International Nuclear Information System (INIS)
Nairz, Olaf; Deutschmann, Heinz; Zehentmayr, Franz; Sedlmayer, Felix; Paracelsus Medical University Salzburg; Merz, Florian; Kopp, Peter; Schoeller, Helmut; Wurstbauer, Karl; Kametriser, Gerhard
2008-01-01
In external beam radiotherapy of prostate cancer, the consideration of various systematic error types leads to wide treatment margins compromising normal tissue tolerance. We investigated if systematic set-up errors can be reduced by a set of initial image-guided radiotherapy (IGRT) sessions. 27 patients received daily IGRT resulting in a set of 882 cone-beam computed tomographies (CBCTs). After matching to bony structures, we analyzed the dimensions of remaining systematic errors from zero up to six initial IGRT sessions and aimed at a restriction of daily IGRT for 10% of all patients. For threshold definition, we determined the standard deviations (SD) of the shift corrections and selected patients out of this range for daily image guidance. To calculate total treatment margins, we demanded for a cumulative clinical target volume (CTV) coverage of at least 95% of the specified dose in 90% of all patients. The gain of accuracy was largest during the first three IGRTs. In order to match precision and workload criteria, thresholds for the SD of the corrections of 3.5 mm, 2.0 mm and 4.5 mm in the left-right (L-R), cranial-caudal (C-C), and anterior-posterior (A-P) direction, respectively, were identified. Including all other error types, the total margins added to the CTV amounted to 8.6 mm in L-R, 10.4 mm in C-C, and 14.4 mm in A-P direction. Only initially performed IGRT might be helpful for eliminating gross systematic errors especially after virtual simulation. However, even with daily IGRT performance, a substantial PTV margin reduction is only achievable by matching internal markers instead of bony anatomical structures. (orig.)
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Different Approaches in Radiation Therapy
Directory of Open Access Journals (Sweden)
Rolf-Dieter eKortmann
2011-12-01
Full Text Available Radiation therapy is a cornerstone in the therapeutic management of craniopharyngioma. The close proximity to neighbouring eloquent structures pose a particular challenge to radiation therapy. Modern treatment technologies including fractionated 3-d conformal radiotherapy, intensity modulated radiation therapy and recently proton therapy are able to precisely cover the target while preserving surrounding tissue,Tumour controls between 80 and in access of 90 % can be achieved. Alternative treatments consisting of radiosurgery, intracavitary application of isotopes and brachytherapy also offer an acceptable tumour control and might be given in selected cases. More research is needed to establish the role of each treatment modality.
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International Nuclear Information System (INIS)
Chennupati, Sravana K; Pelizzari, Charles A; Kunnavakkam, Rangesh; Liauw, Stanley L
2014-01-01
The objective of this study was to assess late toxicity and quality of life (QOL) for patients receiving definitive intensity-modulated radiotherapy (IMRT) and image-guided radiation therapy (IGRT) with regard to normal tissue sparing objectives. Three hundred and seventy-two consecutive men treated with definitive IMRT for prostate adenocarcinoma. Toxicity was graded by CTC v3.0 genitourinary (GU) and gastrointestinal (GI) toxicity at each follow-up visit. Patient-reported QOL (EPIC-26) was prospectively collected for a subset of men. Dosimetric data for bladder and rectum were compared to toxicity and QOL global domain scores, specifically analyzing outcomes for men who met ideal rectal constraints (V70 <10%, V65 <20%, V40 <40%). The median age and prescription dose was 69 years and 76 Gy, respectively. Median follow-up was 47 months. At 4 years, freedom from Grade 2 (FFG2) GI toxicity was 92% and FFG2 GU toxicity was 76%. On univariate analysis, current smoking, larger bladder volume, and higher RT dose were associated with decreased FFG2 GU toxicity, while use of anticoagulation, increasing age, and not meeting ideal rectal constraints were associated with decreased FFG2 GI toxicity (all P ≤ 0.05). Bowel QOL remained stable over the 2-year follow-up period and was higher for patients who met ideal rectal constraints (P = 0.05). IMRT with IGRT is associated with low rates of severe toxicity and a high GI and GU QOL. The use of strict rectal constraints can further improve GI QOL and reduce GI toxicity
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Modern Radiation Therapy for Hodgkin Lymphoma
DEFF Research Database (Denmark)
Specht, Lena; Yahalom, Joachim; Illidge, Tim
2014-01-01
Radiation therapy (RT) is the most effective single modality for local control of Hodgkin lymphoma (HL) and an important component of therapy for many patients. These guidelines have been developed to address the use of RT in HL in the modern era of combined modality treatment. The role of reduced...... on Radiation Units and Measurements concepts of gross tumor volume, clinical target volume, internal target volume, and planning target volume are used for defining the targeted volumes. Newer treatment techniques, including intensity modulated radiation therapy, breath-hold, image guided radiation therapy......, and 4-dimensional imaging, should be implemented when their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control. The highly conformal involved node radiation therapy (INRT), recently introduced for patients for whom...
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Analysis of PTV margin for IMRT and VMAT techniques in prostate cancer using IGRT
International Nuclear Information System (INIS)
Sandrini, E.S.; Silveira, T.B.; Vieira, D.S.; Anjos, L.E.A.; Lopez, J.C.C.; Batista, D.V.S.
2014-01-01
Clinical radiotherapy procedures aim at high precision. However, there are many errors sources that act during treatment preparation and execution that limit its accuracy. The use of imaged-guided radiotherapy (IGRT) increases the agreement between the planned dose and the actual dose deposited in the target, at the same time allows to evaluate the uncertainties related to the setup and a possible reduction in the planning target volume (PTV) margin. Thus the aim of this study was to determine the best PTV margin to be used in radiotherapy treatment of prostate cancer using intensity modulated radiotherapy (IMRT) and volumetric modulated arc radiotherapy (VMAT) techniques associated with IGRT. A total of four patients with prostate daily cone beam computed tomography (CBCT) were analyzed. Systematic and random errors were calculated statistically based on the displacements couch for 128 CBCTs. It was found that a symmetric margin of 0.75 cm from clinical treatment volume (CTV) to PTV is sufficient to encompass the uncertainties inherent to the treatment applying IGRT. Besides without that and maintaining the same tumor control probability, a symmetric margin of 1,24 cm would be necessary. This study showed that using daily image verification the setup errors are reduced, which generates a lower PTV margin. (author)
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Radiation therapy for gastric cancer
International Nuclear Information System (INIS)
Dobelbower, R.R.; Bagne, F.; Ajlouni, M.I.; Milligan, A.J.
1988-01-01
Adenocarcinoma of the stomach is a moderately radioresponsive neoplasm. Attempts to treat patients with unresectable disease with external beam radiation therapy alone have generally failed because of problems with tumor localization and adequate dose delivery as well as the inherent radioresponsiveness of the gastric mucosa and the organs intimately related to the stomach. Combining external beam therapy and chemotherapy (acting as a systemic agent and as a radiosensitizer) seems to be of some (albeit limited) benefit in the management of unresectable adenocarcinoma of the stomach. Optimum combinations of radiation therapy, chemotherapy, and radiation sensitizers in this situation remain to be determined. The authors discuss strides which have been made in the treatment of gastric cancer. They also address the unanswered clinical questions which remain regarding the use of radiation therapy in the treatment of this highly lethal disease
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Why do patients drop out during radiation therapy?
International Nuclear Information System (INIS)
Huh, Seung Jae; Ahn, Yong Chan; Kim, Dae Yong; Shin, Kyung Hwan; Lee, Kyu Chan; Chong, Won A; Kim, Hyun Joo; Wu, Hong Gyun
1998-01-01
This study is to see how much proportion of the patients receiving radiation therapy drop out during radiation therapy and to analyze the reason for the incomplete treatment. The base population of this study was 1,100 patients with registration numbers 901 through 2,000 at Department of Radiation Oncology, Samsung Medical Center, Seoul, Korea. Authors investigated the incidence of incomplete radiation therapy, which was defined as less than 95% of initially planned radiation dose, and the reasons for incomplete radiation therapy. One hundred and twenty eight patients (12%) did not complete the planned radiation therapy. The performance status of the incompletely treated patients was generally poorer than that of the base population, and the aim of radiation therapy was more commonly palliative. The most common reason for not completing the planned treatment was the patients' refusal of further radiation therapy because of the distrust of radiation therapy and/or the poor economic status. Careful case selection for radiation therapy with consideration of the socioeconomic status of the patients in addition to the clinical indication would be necessary for the reduction of incomplete treatment, especially in the palliative setting
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42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.
2010-10-01
... 42 Public Health 2 2010-10-01 2010-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy and...
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Radiation therapy is a type of cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors. Learn about the types of radiation, why side effects happen, which ones you might have, and more.
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Radiation therapy of thoracic and abdominal tumors
International Nuclear Information System (INIS)
LaRue, S.M.; Gillette, S.M.; Poulson, J.M.
1995-01-01
Until recently, radiotherapy of thoracic and abdominal tumors in animals has been limited. However, the availability of computerized tomography and other imaging techniques to aid in determining the extent of tumor, an increase in knowledge of dose tolerance of regional organs, the availability of isocentrically mounted megavoltage machines, and the willingness of patients to pursue more aggressive treatment is making radiation therapy of tumors in these regions far more common. Tumor remission has been reported after radiation therapy of thymomas. Radiation therapy has been used to treat mediastinal lymphoma refractory to chemotherapy, and may be beneficial as part of the initial treatment regimen for this disease. Chemodectomas are responsive to radiation therapy in human patients, and favorable response has also been reported in dogs. Although primary lung tumors in dogs are rare, in some cases radiation therapy could be a useful primary or adjunctive therapy. Lung is the dose-limiting organ in the thorax. Bladder and urethral tumors in dogs have been treated using intraoperative and external-beam radiation therapy combined with chemotherapy. These tumors are difficult to control locally with surgery alone, although the optimal method of combining treatment modalities has not been established. Local control of malignant perianal tumors is also difficult to achieve with surgery alone, and radiation therapy should be used. Intraoperative radiation therapy combined with external-beam radiation therapy has been used for the management of metastatic carcinoma to the sublumbar lymph nodes. Tolerance of retroperitoneal tissues may be decreased by disease or surgical manipulation
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International Nuclear Information System (INIS)
Mein, S; Rankine, L; Adamovics, J; Li, H; Oldham, M
2016-01-01
Purpose: To develop, evaluate and apply a novel high-resolution 3D remote dosimetry protocol for validation of MRI guided radiation therapy treatments (MRIdian by ViewRay™). We demonstrate the first application of the protocol (including two small but required new correction terms) utilizing radiochromic 3D plastic PRESAGE™ with optical-CT readout. Methods: A detailed study of PRESAGE™ dosimeters (2kg) was conducted to investigate the temporal and spatial stability of radiation induced optical density change (ΔOD) over 8 days. Temporal stability was investigated on 3 dosimeters irradiated with four equally-spaced square 6MV fields delivering doses between 10cGy and 300cGy. Doses were imaged (read-out) by optical-CT at multiple intervals. Spatial stability of ΔOD response was investigated on 3 other dosimeters irradiated uniformly with 15MV extended-SSD fields with doses of 15cGy, 30cGy and 60cGy. Temporal and spatial (radial) changes were investigated using CERR and MATLAB’s Curve Fitting Tool-box. A protocol was developed to extrapolate measured ΔOD readings at t=48hr (the typical shipment time in remote dosimetry) to time t=1hr. Results: All dosimeters were observed to gradually darken with time (<5% per day). Consistent intra-batch sensitivity (0.0930±0.002 ΔOD/cm/Gy) and linearity (R2=0.9996) was observed at t=1hr. A small radial effect (<3%) was observed, attributed to curing thermodynamics during manufacture. The refined remote dosimetry protocol (including polynomial correction terms for temporal and spatial effects, CT and CR) was then applied to independent dosimeters irradiated with MR-IGRT treatments. Excellent line profile agreement and 3D-gamma results for 3%/3mm, 10% threshold were observed, with an average passing rate 96.5%± 3.43%. Conclusion: A novel 3D remote dosimetry protocol is presented capable of validation of advanced radiation treatments (including MR-IGRT). The protocol uses 2kg radiochromic plastic dosimeters read-out by
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Energy Technology Data Exchange (ETDEWEB)
Mein, S [Duke University Medical Physics Graduate Program (United States); Rankine, L [Department of Radiation Oncology, University of North Carolina in Chapel Hill (United States); Department of Radiation Oncology, Washington University School of Medicine (United States); Adamovics, J [Department of Chemistry and Biology, Rider University, Lawrenceville, NJ (United States); Li, H [Department of Radiation Oncology, Washington University School of Medicine (United States); Oldham, M [Department of Radiation Oncology, Duke University Medical Center (United States)
2016-06-15
Purpose: To develop, evaluate and apply a novel high-resolution 3D remote dosimetry protocol for validation of MRI guided radiation therapy treatments (MRIdian by ViewRay™). We demonstrate the first application of the protocol (including two small but required new correction terms) utilizing radiochromic 3D plastic PRESAGE™ with optical-CT readout. Methods: A detailed study of PRESAGE™ dosimeters (2kg) was conducted to investigate the temporal and spatial stability of radiation induced optical density change (ΔOD) over 8 days. Temporal stability was investigated on 3 dosimeters irradiated with four equally-spaced square 6MV fields delivering doses between 10cGy and 300cGy. Doses were imaged (read-out) by optical-CT at multiple intervals. Spatial stability of ΔOD response was investigated on 3 other dosimeters irradiated uniformly with 15MV extended-SSD fields with doses of 15cGy, 30cGy and 60cGy. Temporal and spatial (radial) changes were investigated using CERR and MATLAB’s Curve Fitting Tool-box. A protocol was developed to extrapolate measured ΔOD readings at t=48hr (the typical shipment time in remote dosimetry) to time t=1hr. Results: All dosimeters were observed to gradually darken with time (<5% per day). Consistent intra-batch sensitivity (0.0930±0.002 ΔOD/cm/Gy) and linearity (R2=0.9996) was observed at t=1hr. A small radial effect (<3%) was observed, attributed to curing thermodynamics during manufacture. The refined remote dosimetry protocol (including polynomial correction terms for temporal and spatial effects, CT and CR) was then applied to independent dosimeters irradiated with MR-IGRT treatments. Excellent line profile agreement and 3D-gamma results for 3%/3mm, 10% threshold were observed, with an average passing rate 96.5%± 3.43%. Conclusion: A novel 3D remote dosimetry protocol is presented capable of validation of advanced radiation treatments (including MR-IGRT). The protocol uses 2kg radiochromic plastic dosimeters read-out by
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Risk analysis of external radiation therapy
International Nuclear Information System (INIS)
Arvidsson, Marcus
2011-09-01
External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy
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Gene expression profiles in cervical cancer with radiation therapy alone and chemo-radiation therapy
International Nuclear Information System (INIS)
Lee, Kyu Chan; Kim, Joo Young; Hwang, You Jin; Kim, Meyoung Kon; Choi, Myung Sun; Kim, Chul Young
2003-01-01
To analyze the gene expression profiles of uterine cervical cancer, and its variation after radiation therapy, with or without concurrent chemotherapy, using a cDNA microarray. Sixteen patients, 8 with squamous cell carcinomas of the uterine cervix, who were treated with radiation alone, and the other 8 treated with concurrent chemo-radiation, were included in the study. Before the starting of the treatment, tumor biopsies were carried out, and the second time biopsies were performed after a radiation dose of 16.2-27 Gy. Three normal cervix tissues were used as a control group. The microarray experiments were performed with 5 groups of the total RNAs extracted individually and then admixed as control, pre-radiation therapy alone, during-radiation therapy alone, pre-chemoradiation therapy, and during chemoradiation therapy. The 33P-labeled cDNAs were synthesized from the total RNAs of each group, by reverse transcription, and then they were hybridized to the cDNA microarray membrane. The gene expression of each microarrays was captured by the intensity of each spot produced by the radioactive isotopes. The pixels per spot were counted with an Arrayguage, and were exported to Microsoft Excel. The data were normalized by the Z transformation, and the comparisons were performed on the Z-ratio values calculated. The expressions of 15 genes, including integrin linked kinase (ILK), CDC28 protein kinase 2, Spry 2, and ERK 3, were increased with the Z-ratio values of over 2.0 for the cervix cancer tissues compared to those for the normal controls. Those genes were involved in cell growth and proliferation, cell cycle control, or signal transduction. The expressions of the other 6 genes, including G protein coupled receptor kinase 6, were decreased with the Z-ratio values of below -2.0. After the radiation therapy, most of the genes, with a previously increase expressions, represented the decreased expression profiles, and the genes, with the Z-ratio values of over 2.0, were
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Three-dimensional conformal radiation therapy: the tomo-therapy approach
International Nuclear Information System (INIS)
Linthout, N.; Verellen, D.; Coninck, P. de; Bel, A.; Storme, G.
2000-01-01
Conformal radiation therapy allows the possibility of delivering high doses at the tumor volume whilst limiting the dose to the surrounding tissues and diminishing the secondary effects. With the example of the conformal radiation therapy used at the AZ VU8 (3DCRT and tomo-therapy), two treatment plans of a left ethmoid carcinoma will be evaluated and discussed in detail. The treatment of ethmoid cancer is technically difficult for both radiation therapy and surgery because of the anatomic constraints and patterns of local spread. A radiation therapy is scheduled to be delivered after surgical resection of the tumor. The treatment plan for the radiation therapy was calculated on a three-dimensional (3D) treatment planning system based on virtual simulation with a beam's eye view: George Sherouse's Gratis. An effort was made to make the plan as conformal and as homogeneous as possible to deliver a dose of 66 Gy in 33 fractions at the tumor bed with a maximum dose of 56 Gy to the right optic nerve and the chiasma. To establish the clinical utility and potential advantages of tomo-therapy over 3DCRT for ethmoid carcinoma, the treatment of this patient was also planned with Peacock Plant. For both treatment plans the isodose distributions and cumulative dose volume histograms (CDVH) were computed. Superimposing the CDVHs yielded similar curves for the target and an obvious improvement for organs at risk such as the chiasma, brainstem and the left eye when applying tomo-therapy. These results have also been reflected in the tumor control probabilities (equal for both plans) and the normal tissue complication probabilities (NTCP), yielding significant reductions in NTCP for tomo-therapy. The probability of uncomplicated tumor control was 52.7% for tomo-therapy against 38.3% for 3DCRT. (authors)
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Protection of the patient in radiation therapy
International Nuclear Information System (INIS)
1991-01-01
In the ICRP report (ICRP-Pub-44) a broad picture of radiotheraphy is presented useful to all involved in the care of cancer patients, for instance to physicians, including medical oncologists, and to medical physicists, radiographers, dosimetrists, and administrators. Information is given on the general principles of radiation therapy including external beam therapy and brachytherapy; the accuracy of radiation delivery and quality assurance; the biological radiation response; the expected risk to specific organs or tissues from therapeutic irradiation; the absorbed dose to tissues inside and outside the useful radiation beams; the organization and planning of radiation oncology services; radiation therapy staff education, training and duties; and finally medical research involving the use of radiation therapy. (orig./HP) [de
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International Nuclear Information System (INIS)
Goodman, Karyn A.; Khalid, Najma; Kachnic, Lisa A.; Minsky, Bruce D.; Crozier, Cheryl; Owen, Jean B.; Devlin, Phillip M.; Thomas, Charles R.
2013-01-01
Background: The specific aim was to determine national patterns of radiation therapy (RT) practice in patients treated for stage IB-IV (nonmetastatic) gastric cancer (GC). Methods and Materials: A national process survey of randomly selected US RT facilities was conducted which retrospectively assessed demographics, staging, geographic region, practice setting, and treatment by using on-site record review of eligible GC cases treated from 2005 to 2007. Three clinical performance measures (CPMs), (1) use of computed tomography (CT)-based treatment planning; (2) use of dose volume histograms (DVHs) to evaluate RT dose to the kidneys and liver; and (3) completion of RT within the prescribed time frame; and emerging quality indicators, (i) use of intensity modulated RT (IMRT); (ii) use of image-guided tools (IGRT) other than CT for RT target delineation; and (iii) use of preoperative RT, were assessed. Results: CPMs were computed for 250 eligible patients at 45 institutions (median age, 62 years; 66% male; 60% Caucasian). Using 2000 American Joint Committee on Cancer criteria, 13% of patients were stage I, 29% were stage II, 32% were stage IIIA, 10% were stage IIIB, and 12% were stage IV. Most patients (43%) were treated at academic centers, 32% were treated at large nonacademic centers, and 25% were treated at small to medium sized facilities. Almost all patients (99.5%) underwent CT-based planning, and 75% had DVHs to evaluate normal tissue doses to the kidneys and liver. Seventy percent of patients completed RT within the prescribed time frame. IMRT and IGRT were used in 22% and 17% of patients, respectively. IGRT techniques included positron emission tomography (n=20), magnetic resonance imaging (n=1), respiratory gating and 4-dimensional CT (n=22), and on-board imaging (n=10). Nineteen percent of patients received preoperative RT. Conclusions: This analysis of radiation practice patterns for treating nonmetastatic GC indicates widespread adoption of CT
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Energy Technology Data Exchange (ETDEWEB)
Goodman, Karyn A., E-mail: goodmank@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Khalid, Najma [Quality Research in Radiation Oncology, American College of Radiology Clinical Research Center, Philadelphia, Pennsylvania (United States); Kachnic, Lisa A. [Department of Radiation Oncology, Boston University Medical Center, Boston, Massachusetts (United States); Minsky, Bruce D. [Department of Radiation Oncology, University of Texas MD, Anderson Cancer Center, Houston, Texas (United States); Crozier, Cheryl; Owen, Jean B. [Quality Research in Radiation Oncology, American College of Radiology Clinical Research Center, Philadelphia, Pennsylvania (United States); Devlin, Phillip M. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, Massachusetts (United States); Thomas, Charles R. [Department of Radiation Medicine, Knight Cancer Institute at the Oregon Health and Science University, Portland, Oregon (United States)
2013-02-01
Background: The specific aim was to determine national patterns of radiation therapy (RT) practice in patients treated for stage IB-IV (nonmetastatic) gastric cancer (GC). Methods and Materials: A national process survey of randomly selected US RT facilities was conducted which retrospectively assessed demographics, staging, geographic region, practice setting, and treatment by using on-site record review of eligible GC cases treated from 2005 to 2007. Three clinical performance measures (CPMs), (1) use of computed tomography (CT)-based treatment planning; (2) use of dose volume histograms (DVHs) to evaluate RT dose to the kidneys and liver; and (3) completion of RT within the prescribed time frame; and emerging quality indicators, (i) use of intensity modulated RT (IMRT); (ii) use of image-guided tools (IGRT) other than CT for RT target delineation; and (iii) use of preoperative RT, were assessed. Results: CPMs were computed for 250 eligible patients at 45 institutions (median age, 62 years; 66% male; 60% Caucasian). Using 2000 American Joint Committee on Cancer criteria, 13% of patients were stage I, 29% were stage II, 32% were stage IIIA, 10% were stage IIIB, and 12% were stage IV. Most patients (43%) were treated at academic centers, 32% were treated at large nonacademic centers, and 25% were treated at small to medium sized facilities. Almost all patients (99.5%) underwent CT-based planning, and 75% had DVHs to evaluate normal tissue doses to the kidneys and liver. Seventy percent of patients completed RT within the prescribed time frame. IMRT and IGRT were used in 22% and 17% of patients, respectively. IGRT techniques included positron emission tomography (n=20), magnetic resonance imaging (n=1), respiratory gating and 4-dimensional CT (n=22), and on-board imaging (n=10). Nineteen percent of patients received preoperative RT. Conclusions: This analysis of radiation practice patterns for treating nonmetastatic GC indicates widespread adoption of CT
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Energy Technology Data Exchange (ETDEWEB)
Anon.
2011-06-15
The volume includes lectures and posters on the following topics: protons and heavy ions - first treatment results; complementary medicine; lung carcinomas; radio-oncology management and centers; benign diseases; IMRT, IGRT. what will be routine? palliative radiotherapy - the role of radio-oncologists; biology and clinics of head-neck-ear tumors; free issues; radiation physics - dosimetric indicators in therapy planning; reduction of treatment regimes - risk or chances in radiotherapy? pancreas carcinomas; prostate carcinomas; individualization in radio-oncology; experimental radiotherapy - new molecular targets; pitfalls of oncological imaging and therapy planning; from cells to patients - the successful history of the ERGF receptor.
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Radiation biology and radiation therapy
International Nuclear Information System (INIS)
Wideroee, R.
1975-01-01
Radiation biology and radiation therapy can be compared with investigations in different layers of earth. Radiation biology works upwards from the elementary foundations, therapy works downwards with roots to secure and improve the clinical 'surface work'. The Ellis formula (Strandquist), which is a collection of clinical experience, is suited to form connections with radiobiology in the middle layers, and cooperation can give impulses for research. The structure and conditions of tumours and the complicated problems met with are discussed, based on the Carmel symposium of 1969. The oxygen problem in anoxic tumours is not yet solved. Experimental investigations of the effect itself give partly contradictory results. From a clinical viewpoint reoxygenation is of the utmost significance for obtaining control over the primary tumour, and advanced irradiation programmes will here give better results than the traditional ones. New chemicals, e.g. R 0 -07-0582, appear to reduce the OER value to 1.5, thereby making neutron therapy superfluous. Finally a problem from fundamental research is dealt with, wherein two hypotheses explaining the β-effect are described. The repair hypothesis gives a simple explanation but leaves many questions unanswered. The other hypothesis explains the β-effect as two neighbouring single breaks of the DNA molecule. It still presents difficulties, and is scarcely the correct explanation. (JIW)
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External Beam Radiation Therapy for Cancer
External beam radiation therapy is used to treat many types of cancer. it is a local treatment, where a machine aims radiation at your cancer. Learn more about different types of external beam radiation therapy, and what to expect if you're receiving treatment.
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Energy Technology Data Exchange (ETDEWEB)
Sandrini, E.S.; Silveira, T.B.; Vieira, D.S.; Batista, D.V.S., E-mail: emmilyfisica@gmail.com [Instituto Nacional de Cancer Jose de Alencar Gomes da Silva, Rio de Janeiro, RJ (Brazil)
2014-12-15
The main application of image-guided radiotherapy (IGRT) in the cancer prostate treatment is to ensure the delivery of the prescribed dose to the tumor. With the modality cone beam computed tomography (CBCT) prostate, seminal vesicles, bladder and rectum can be previewed before each treatment and the actual dose delivered to these organs can be controlled, through the alignment of patient isocenter. The aim of this study was to analyze the tumor coverage and dose to organs at risk effectively obtained during the patient's treatment. Three patients with prostate cancer were treated with intensity modulated radiotherapy (IMRT) or volumetric modulated arc radiotherapy (VMAT) techniques with 74 Gy and 2 Gy per fraction. It was performed daily isocenter location of the prostate with CBCT. A radioncologist drew the clinical target volume (CTV), rectum and bladder in CBCT's and treatment fields were applied retrospectively in each CBCT for dose calculation. For the CTV it was considered the D95 (dose that covers 95% of the volume), for the rectum V50 (volume receiving 50 Gy), V60, V65 and V70 and for bladder V65 and V70. The average D95 of the prostate after the offset was 202 cGy, the V50, V60 and V65 of the rectum for one patient was reduced by 9.6%, 16.6% and 31%, respectively, and V65 of the bladder to another patient was also reduced by 3.5% in IGRT. The results showed that the use of IGRT provided a reduction in the irradiated volume of healthy organs. Thus it is concluded that the use of daily CBCT allows reproducibility of treatment, reducing delayed toxicities and increasing the probability of tumor control. (author)
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International Nuclear Information System (INIS)
Ji, Youn-Sang; Dong, Kyung-Rae; Kim, Chang-Bok; Choi, Seong-Kwan; Chung, Woon-Kwan; Lee, Jong-Woong
2011-01-01
Highlights: → Evaluation of DVH from 3D CRT, IMRT and Tomo therapy was conducted for tumor therapy. → The doses of GTV and CTV were compared using DVHs from 3D CRT, IMRT and Tomo therapy. → The GTV was higher when Tomo therapy was used, while the doses of critical organ were low. → They said that Tomo therapy satisfied the goal of radiation therapy more than the others. - Abstract: Evaluation of dose-volume histograms from three-dimensional conformal radiation therapy (3D CRT), intensity-modulated radiation therapy (IMRT), and Tomo therapy was conducted. These three modalities are among the diverse treatment systems available for tumor therapy. Three patients who received tumor therapy for a malignant oligodendroglioma in the cranium, nasopharyngeal carcinoma in the cervical neck, and prostate cancer in the pelvis were selected as study subjects. Therapy plans were made for the three patients before dose-volume histograms were obtained. The doses of the gross tumor volume (GTV) and the clinical target volume (CTV) were compared using the dose-volume histograms obtained from the LINAC-based 3D CRT, IMRT planning station (Varian Eclipse-Varian, version 8.1), and Tomo therapy planning station. In addition, the doses of critical organs in the cranium, cervix, and pelvis that should be protected were compared. The GTV was higher when Tomo therapy was used compared to 3D CRT and the LINAC-based IMRT, while the doses of critical organ tissues that required protection were low. These results demonstrated that Tomo therapy satisfied the ultimate goal of radiation therapy more than the other therapies.
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Radiation therapy for metastatic spinal tumors
International Nuclear Information System (INIS)
Kida, Akio; Fukuda, Haruyuki; Taniguchi, Shuji; Sakai, Kazuaki
2000-01-01
The results of radiation therapy for metastatic spinal tumors were evaluated in terms of pain relief, improvement of neurological impairment, and survival. Between 1986 and 1995, 52 symptomatic patients with metastatic spinal tumors treated with radiation therapy were evaluated. The patients all received irradiation of megavoltage energy. Therapeutic efficacy was evaluated in terms of pain relief and improvement of neurological impairment. Pain relief was observed in 29 (61.7%) of 47 patients with pain. Therapy was effective for 17 (70.8%) of 24 patients without neurological impairment, and efficacy was detected in 12 (52.2%) of 23 patients with neurological impairment. Improvement of neurological symptoms was obtained in seven (25.0%) of 28 patients with neurological impairment. Radiation therapy was effective for pain relief in patients with metastatic spinal tumors. In patients with neurological impairment, less pain relief was observed than in those without impairment. Improvement of neurological impairment was restricted, but radiation therapy was thought to be effective in some cases in the early stage of neurological deterioration. Radiation therapy for metastatic spinal tumors contraindicated for surgery was considered effective for improvement of patients' activities of daily living. (author)
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Radiation therapy in the treatment of hilar cholangiocarcinoma
International Nuclear Information System (INIS)
Jing Jin; Zhai Renyou
2007-01-01
The incidence of hilar cholangiocarcinoma is very rare worldwide. Radical resection is the only prognostic factor for long survival in patients with hilar cholangiocarcinoma. Postoperative radiation therapy can improve local control and survival rates for patients with palliative resection, but it remains controversial in patients with radical resection. Biliary drainage can effectively release bile duct obstruction for the majority of patients with locally advanced disease, and may even prolong survival when combined with radiation therapy. Radiation therapy includes extrernal beam therapy alone, external beam therapy with intraluminal brachytheapy and new radiation technique, such as three dimentional conformal therapy and intensity modulated radiation therapy. The propective randomized clinical study is needed for further investigation in the role of combined modality therapy especially for hilar cholangiocarcinoma. (authors)
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Clinical experience of radiation therapy for Graves` ophthalmopathy
Energy Technology Data Exchange (ETDEWEB)
Takahashi, Takeo; Mitsuhashi, Norio; Nagashima, Hisako; Sakurai, Hideyuki; Murata, Osamu; Ishizeki, Kei; Shimaya, Sanae; Hayakawa, Kazushige; Niibe, Hideo [Gunma Univ., Maebashi (Japan). School of Medicine
1996-11-01
The effect of radiation therapy for Graves` ophthalmopathy was evaluated. Ten patients with Graves` ophthalmopathy were treated with radiation therapy between 1992 and 1993 in Gunma University Hospital. All patients had a past history of hyperthyroidism and received 2,000 cGy to the retrobulbar tissues in 20 fractions. Nine of ten patients were treated with radiation therapy after the failure of corticosteroids. Six patients (60%) showed good or excellent responses. The exophthalmos type was more responsive to radiation therapy than the double vision type in this series. Two of five patients with the exophthalmos type demonstrated excellent responses, and their symptoms disappeared almost completely. The improvement of symptoms appeared within 3-6 months, and obvious clinical effects were demonstrated after 6 months of radiotherapy. Radiation therapy was well tolerated, and we have not observed any side effects of radiation therapy. In conclusion, radiation therapy is effective treatment for Graves` ophthalmopathy. (author)
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Clinical experience of radiation therapy for Graves' ophthalmopathy
International Nuclear Information System (INIS)
Takahashi, Takeo; Mitsuhashi, Norio; Nagashima, Hisako; Sakurai, Hideyuki; Murata, Osamu; Ishizeki, Kei; Shimaya, Sanae; Hayakawa, Kazushige; Niibe, Hideo
1996-01-01
The effect of radiation therapy for Graves' ophthalmopathy was evaluated. Ten patients with Graves' ophthalmopathy were treated with radiation therapy between 1992 and 1993 in Gunma University Hospital. All patients had a past history of hyperthyroidism and received 2,000 cGy to the retrobulbar tissues in 20 fractions. Nine of ten patients were treated with radiation therapy after the failure of corticosteroids. Six patients (60%) showed good or excellent responses. The exophthalmos type was more responsive to radiation therapy than the double vision type in this series. Two of five patients with the exophthalmos type demonstrated excellent responses, and their symptoms disappeared almost completely. The improvement of symptoms appeared within 3-6 months, and obvious clinical effects were demonstrated after 6 months of radiotherapy. Radiation therapy was well tolerated, and we have not observed any side effects of radiation therapy. In conclusion, radiation therapy is effective treatment for Graves' ophthalmopathy. (author)
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Radiation therapy for carcinoma of the endometrium
International Nuclear Information System (INIS)
Potish, R.A.
1987-01-01
Carcinoma of the endometrium is the most common malignant tumor in the female genital tract. Radiation therapy continues to play a major role in the management of endometrial carcinoma, both as primary therapy and as adjuvant treatment. The utility of pelvic external beam therapy and intracavitary therapy is long established. However, the modern era of surgical staging has lead to an appreciation of the role of radiation therapy beyond the pelvis. Radiation therapy has been shown to be of particular benefit in peritoneal and nodal spread. The classic management of endometrial cancer is reviewed and relatively new and somewhat controversial topics, such as preoperative intracavitary therapy followed by external beam therapy are discussed
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DNA repair related to radiation therapy
International Nuclear Information System (INIS)
Klein, W.
1979-01-01
The DNA excision repair capacity of peripheral human lymphocytes after radiation therapy has been analyzed. Different forms of application of the radiation during the therapy have been taken into account. No inhibition of repair was found if cells were allowed a certain amount of accomodation to radiation, either by using lower doses or longer application times. (G.G.)
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Radiation therapy facilities in the United States
International Nuclear Information System (INIS)
Ballas, Leslie K.; Elkin, Elena B.; Schrag, Deborah; Minsky, Bruce D.; Bach, Peter B.
2006-01-01
Purpose: About half of all cancer patients in the United States receive radiation therapy as a part of their cancer treatment. Little is known, however, about the facilities that currently deliver external beam radiation. Our goal was to construct a comprehensive database of all radiation therapy facilities in the United States that can be used for future health services research in radiation oncology. Methods and Materials: From each state's health department we obtained a list of all facilities that have a linear accelerator or provide radiation therapy. We merged these state lists with information from the American Hospital Association (AHA), as well as 2 organizations that audit the accuracy of radiation machines: the Radiologic Physics Center (RPC) and Radiation Dosimetry Services (RDS). The comprehensive database included all unique facilities listed in 1 or more of the 4 sources. Results: We identified 2,246 radiation therapy facilities operating in the United States as of 2004-2005. Of these, 448 (20%) facilities were identified through state health department records alone and were not listed in any other data source. Conclusions: Determining the location of the 2,246 radiation facilities in the United States is a first step in providing important information to radiation oncologists and policymakers concerned with access to radiation therapy services, the distribution of health care resources, and the quality of cancer care
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Involved Node Radiation Therapy
DEFF Research Database (Denmark)
Maraldo, Maja V; Aznar, Marianne C; Vogelius, Ivan R
2012-01-01
PURPOSE: The involved node radiation therapy (INRT) strategy was introduced for patients with Hodgkin lymphoma (HL) to reduce the risk of late effects. With INRT, only the originally involved lymph nodes are irradiated. We present treatment outcome in a retrospective analysis using this strategy...... to 36 Gy). Patients attended regular follow-up visits until 5 years after therapy. RESULTS: The 4-year freedom from disease progression was 96.4% (95% confidence interval: 92.4%-100.4%), median follow-up of 50 months (range: 4-71 months). Three relapses occurred: 2 within the previous radiation field......, and 1 in a previously uninvolved region. The 4-year overall survival was 94% (95% confidence interval: 88.8%-99.1%), median follow-up of 58 months (range: 4-91 months). Early radiation therapy toxicity was limited to grade 1 (23.4%) and grade 2 (13.8%). During follow-up, 8 patients died, none from HL, 7...
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Energy Technology Data Exchange (ETDEWEB)
Lee, Katrina, E-mail: Trinabena23@gmail.com; Lenards, Nishele; Holson, Janice
2016-04-01
The hippocampus is responsible for memory and cognitive function. An ongoing phase II clinical trial suggests that sparing dose to the hippocampus during whole-brain radiation therapy can help preserve a patient's neurocognitive function. Progressive research and advancements in treatment techniques have made treatment planning more sophisticated but beneficial for patients undergoing treatment. The aim of this study is to evaluate and compare hippocampal sparing whole-brain (HS-WB) radiation therapy treatment planning techniques using volume-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). We randomly selected 3 patients to compare different treatment techniques that could be used for reducing dose to the hippocampal region. We created 2 treatment plans, a VMAT and an IMRT, from each patient's data set and planned on the Eclipse 11.0 treatment planning system (TPS). A total of 6 plans (3 IMRT and 3 VMAT) were created and evaluated for this case study. The physician contoured the hippocampus as per the Radiation Therapy Oncology Group (RTOG) 0933 protocol atlas. The organs at risk (OR) were contoured and evaluated for the plan comparison, which included the spinal cord, optic chiasm, the right and left eyes, lenses, and optic nerves. Both treatment plans produced adequate coverage on the planning target volume (PTV) while significantly reducing dose to the hippocampal region. The VMAT treatment plans produced a more homogenous dose distribution throughout the PTV while decreasing the maximum point dose to the target. However, both treatment techniques demonstrated hippocampal sparing when irradiating the whole brain.
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International Nuclear Information System (INIS)
Lee, Katrina; Lenards, Nishele; Holson, Janice
2016-01-01
The hippocampus is responsible for memory and cognitive function. An ongoing phase II clinical trial suggests that sparing dose to the hippocampus during whole-brain radiation therapy can help preserve a patient's neurocognitive function. Progressive research and advancements in treatment techniques have made treatment planning more sophisticated but beneficial for patients undergoing treatment. The aim of this study is to evaluate and compare hippocampal sparing whole-brain (HS-WB) radiation therapy treatment planning techniques using volume-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). We randomly selected 3 patients to compare different treatment techniques that could be used for reducing dose to the hippocampal region. We created 2 treatment plans, a VMAT and an IMRT, from each patient's data set and planned on the Eclipse 11.0 treatment planning system (TPS). A total of 6 plans (3 IMRT and 3 VMAT) were created and evaluated for this case study. The physician contoured the hippocampus as per the Radiation Therapy Oncology Group (RTOG) 0933 protocol atlas. The organs at risk (OR) were contoured and evaluated for the plan comparison, which included the spinal cord, optic chiasm, the right and left eyes, lenses, and optic nerves. Both treatment plans produced adequate coverage on the planning target volume (PTV) while significantly reducing dose to the hippocampal region. The VMAT treatment plans produced a more homogenous dose distribution throughout the PTV while decreasing the maximum point dose to the target. However, both treatment techniques demonstrated hippocampal sparing when irradiating the whole brain.
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External radiation therapy of prostatic carcinoma and its relationship to hormonal therapy
International Nuclear Information System (INIS)
Takada, Chitose; Ito, Koushiro; Nishi, Junko; Yamamoto, Toshihiro; Hatanaka, Yoshimi; Baba, Yuji; Takahashi, Mutsumasa.
1995-01-01
From 1980 to 1990, a total of 54 patients with prostatic carcinoma were treated with external radiation therapy at the Kumamoto National Hospital. Ten patients were classified as Stage B, 22 as Stage C, and another 22 as Stage D according to the American Urological Association Clinical Staging System. The 5-year survival for all 54 patients was 30%. The 5-year disease-specific survival was 67% for Stage B, 47% for Stage C, and 26% for Stage D. The 5-year survival was 43% for patients in whom radiation therapy was initiated immediately after the first diagnosis or with less than one year of hormonal therapy, while it was 0% for patients in whom radiation therapy was initiated after more than one year of hormonal therapy (p=0.01). The cause of intercurrent death was acute myocardial infarction in four patients and acute cardiac failure in one. Four of these patients received hormonal therapy for more than one year. The incidence of radiation-induced proctitis was not severe. This study suggests that long-term hormonal therapy prior to radiation therapy worsens the prognosis of patients with prostatic carcinoma. (author)
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SU-F-T-472: Validation of Absolute Dose Measurements for MR-IGRT With and Without Magnetic Field
International Nuclear Information System (INIS)
Green, O; Li, H; Goddu, S; Mutic, S; Kawrakow, I
2016-01-01
Purpose: To validate absolute dose measurements for a MR-IGRT system without presence of the magnetic field. Methods: The standard method (AAPM’s TG-51) of absolute dose measurement with ionization chambers was tested with and without the presence of the magnetic field for a clinical 0.32-T Co-60 MR-IGRT system. Two ionization chambers were used - the Standard Imaging (Madison, WI) A18 (0.123 cc) and the PTW (Freiburg, Germany). A previously reported Monte Carlo simulation suggested a difference on the order of 0.5% for dose measured with and without the presence of the magnetic field, but testing this was not possible until an engineering solution to allow the radiation system to be used without the nominal magnetic field was found. A previously identified effect of orientation in the magnetic field was also tested by placing the chamber either parallel or perpendicular to the field and irradiating from two opposing angles (90 and 270). Finally, the Imaging and Radiation Oncology Core provided OSLD detectors for five irradiations each with and without the field - with two heads at both 0 and 90 degrees, and one head at 90 degrees only as it doesn’t reach 0 (IEC convention). Results: For the TG-51 comparison, expected dose was obtained by decaying values measured at the time of source installation. The average measured difference was 0.4%±0.12% for A18 and 0.06%±0.15% for Farmer chamber. There was minimal (0.3%) orientation dependence without the magnetic field for the A18 chamber, while previous measurements with the magnetic field had a deviation of 3.2% with chamber perpendicular to magnetic field. Results reported by IROC for the OSLDs with and without the field had a maximum difference of 2%. Conclusion: Accurate absolute dosimetry was verified by measurement under the same conditions with and without the magnetic field for both ionization chambers and independently-verifiable OSLDs.
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Communication skills training for radiation therapists: preparing patients for radiation therapy.
Halkett, Georgia; O'Connor, Moira; Aranda, Sanchia; Jefford, Michael; Merchant, Susan; York, Debra; Miller, Lisa; Schofield, Penelope
2016-12-01
Patients sometimes present for radiation therapy with high levels of anxiety. Communication skills training may assist radiation therapists to conduct more effective consultations with patients prior to treatment planning and treatment commencement. The overall aim of our research is to examine the effectiveness of a preparatory programme 'RT Prepare' delivered by radiation therapists to reduce patient psychological distress. The purpose of this manuscript was to describe the communication skills workshops developed for radiation therapists and evaluate participants' feedback. Radiation therapists were invited to participate in two communication skills workshops run on the same day: (1) Consultation skills in radiation therapy and (2) Eliciting and responding to patients' emotional cues. Evaluation forms were completed. Radiation therapists' consultations with patients were then audio-recorded and evaluated prior to providing a follow-up workshop with participants. Nine full day workshops were held. Sixty radiation therapists participated. Positive feedback was received for both workshops with 88% or more participants agreeing or strongly agreeing with all the statements about the different components of the two workshops. Radiation therapists highlighted participating in role play with an actor, discussing issues; receiving feedback; acquiring new skills and knowledge; watching others role play and practicing with checklist were their favourite aspects of the initial workshop. The follow-up workshops provided radiation therapists with feedback on how they identified and addressed patients' psychological concerns; time spent with patients during consultations and the importance of finding private space for consultations. Communication skills training consisting of preparing patients for radiation therapy and eliciting and responding to emotional cues with follow-up workshops has the potential to improve radiation therapists' interactions with patients undergoing
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Music therapy CD creation for initial pediatric radiation therapy: a mixed methods analysis.
Barry, Philippa; O'Callaghan, Clare; Wheeler, Greg; Grocke, Denise
2010-01-01
A mixed methods research design was used to investigate the effects of a music therapy CD (MTCD) creation intervention on pediatric oncology patients' distress and coping during their first radiation therapy treatment. The music therapy method involved children creating a music CD using interactive computer-based music software, which was "remixed" by the music therapist-researcher to extend the musical material. Eleven pediatric radiation therapy outpatients aged 6 to 13 years were randomly assigned to either an experimental group, in which they could create a music CD prior to their initial treatment to listen to during radiation therapy, or to a standard care group. Quantitative and qualitative analyses generated multiple perceptions from the pediatric patients, parents, radiation therapy staff, and music therapist-researcher. Ratings of distress during initial radiation therapy treatment were low for all children. The comparison between the two groups found that 67% of the children in the standard care group used social withdrawal as a coping strategy, compared to 0% of the children in the music therapy group; this trend approached significance (p = 0.076). MTCD creation was a fun, engaging, and developmentally appropriate intervention for pediatric patients, which offered a positive experience and aided their use of effective coping strategies to meet the demands of their initial radiation therapy treatment.
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Pediatric radiation therapy. A Japanese nationwide survey
International Nuclear Information System (INIS)
Nemoto, Kenji; Nagata, Yasushi; Hirokawa, Yutaka
2006-01-01
A national survey on the current status of pediatric radiation therapy was performed in October 2004. We sent questionnaires to 638 radiotherapy facilities in Japan (except for Kansai area) and 245 responses were analyzed. According to the database of committee of Japanese Society of Therapeutic Radiology and Oncology (JASTRO), the number of pediatric patients who received radiation therapy during 2003 in Japan was 1,101. The most frequent pediatric malignancy was brain tumor, followed by leukemia and lymphoma. The total effort of radiation therapy for children was two to six times larger than that for adult patients. An additional fee seems to be necessary for the highly technical and laborious radiation therapy required for children. (author)
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Lee, Katrina; Lenards, Nishele; Holson, Janice
2016-01-01
The hippocampus is responsible for memory and cognitive function. An ongoing phase II clinical trial suggests that sparing dose to the hippocampus during whole-brain radiation therapy can help preserve a patient׳s neurocognitive function. Progressive research and advancements in treatment techniques have made treatment planning more sophisticated but beneficial for patients undergoing treatment. The aim of this study is to evaluate and compare hippocampal sparing whole-brain (HS-WB) radiation therapy treatment planning techniques using volume-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). We randomly selected 3 patients to compare different treatment techniques that could be used for reducing dose to the hippocampal region. We created 2 treatment plans, a VMAT and an IMRT, from each patient׳s data set and planned on the Eclipse 11.0 treatment planning system (TPS). A total of 6 plans (3 IMRT and 3 VMAT) were created and evaluated for this case study. The physician contoured the hippocampus as per the Radiation Therapy Oncology Group (RTOG) 0933 protocol atlas. The organs at risk (OR) were contoured and evaluated for the plan comparison, which included the spinal cord, optic chiasm, the right and left eyes, lenses, and optic nerves. Both treatment plans produced adequate coverage on the planning target volume (PTV) while significantly reducing dose to the hippocampal region. The VMAT treatment plans produced a more homogenous dose distribution throughout the PTV while decreasing the maximum point dose to the target. However, both treatment techniques demonstrated hippocampal sparing when irradiating the whole brain. Copyright © 2016 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.
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International Nuclear Information System (INIS)
Green, O; Mutic, S; Li, H; Low, D; Chmielewski, T; Fought, G; Hernandez, M; Kawrakow, I; Sharma, A; Shvartsman, S; Dempsey, J
2016-01-01
Purpose: To describe the performance of a linear accelerator operating in a compact MRI-guided radiation therapy system. Methods: A commercial linear accelerator was placed in an MRI unit that is employed in a commercial MR-based image guided radiation therapy (IGRT) system. The linear accelerator components were placed within magnetic field-reducing hardware that provided magnetic fields of less than 40 G for the magnetron, gun driver, and port circulator, with 1 G for the linear accelerator. The system did not employ a flattening filter. The test linear accelerator was an industrial 4 MV model that was employed to test the ability to run an accelerator in the MR environment. An MR-compatible diode detector array was used to measure the beam profiles with the accelerator outside and inside the MR field and with the gradient coils on and off to examine if there was any effect on the delivered dose distribution. The beam profiles and time characteristics of the beam were measured. Results: The beam profiles exhibited characteristic unflattened Bremsstrahlung features with less than ±1.5% differences in the profile magnitude when the system was outside and inside the magnet and less than 1% differences with the gradient coils on and off. The central axis dose rate fluctuated by less than 1% over a 30 second period when outside and inside the MRI. Conclusion: A linaccompatible MR design has been shown to be effective in not perturbing the operation of a commercial linear accelerator. While the accelerator used in the tests was 4MV, there is nothing fundamentally different with the operation of a 6MV unit, implying that the design will enable operation of the proposed clinical unit. Research funding provided by ViewRay, Inc.
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Energy Technology Data Exchange (ETDEWEB)
Green, O; Mutic, S; Li, H [Washington University School of Medicine, St. Louis, MO (United States); Low, D [University of California, Los Angeles, CA (United States); Chmielewski, T; Fought, G; Hernandez, M; Kawrakow, I; Sharma, A; Shvartsman, S; Dempsey, J [ViewRay, Inc., Oakwood Village, OH (United States)
2016-06-15
Purpose: To describe the performance of a linear accelerator operating in a compact MRI-guided radiation therapy system. Methods: A commercial linear accelerator was placed in an MRI unit that is employed in a commercial MR-based image guided radiation therapy (IGRT) system. The linear accelerator components were placed within magnetic field-reducing hardware that provided magnetic fields of less than 40 G for the magnetron, gun driver, and port circulator, with 1 G for the linear accelerator. The system did not employ a flattening filter. The test linear accelerator was an industrial 4 MV model that was employed to test the ability to run an accelerator in the MR environment. An MR-compatible diode detector array was used to measure the beam profiles with the accelerator outside and inside the MR field and with the gradient coils on and off to examine if there was any effect on the delivered dose distribution. The beam profiles and time characteristics of the beam were measured. Results: The beam profiles exhibited characteristic unflattened Bremsstrahlung features with less than ±1.5% differences in the profile magnitude when the system was outside and inside the magnet and less than 1% differences with the gradient coils on and off. The central axis dose rate fluctuated by less than 1% over a 30 second period when outside and inside the MRI. Conclusion: A linaccompatible MR design has been shown to be effective in not perturbing the operation of a commercial linear accelerator. While the accelerator used in the tests was 4MV, there is nothing fundamentally different with the operation of a 6MV unit, implying that the design will enable operation of the proposed clinical unit. Research funding provided by ViewRay, Inc.
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International Nuclear Information System (INIS)
Bouchet, Audrey; Bräuer-Krisch, Elke; Prezado, Yolanda; El Atifi, Michèle; Rogalev, Léonid; Le Clec'h, Céline; Laissue, Jean Albert; Pelletier, Laurent; Le Duc, Géraldine
2016-01-01
Purpose: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly focused synchrotron beam into arrays of parallel microbeams, typically a few tens of microns wide and depositing several hundred grays. This irradiation modality was shown to have a high therapeutic impact on tumors, especially in intracranial locations. However, mechanisms responsible for such a property are not fully understood. Methods and Materials: Thanks to recent progress in dosimetry, we compared the effect of MRT and synchrotron broad beam (BB) radiation therapy delivered at comparable doses (equivalent to MRT valley dose) on tumor growth control and on classical radiobiological functions by histologic evaluation and/or transcriptomic analysis. Results: MRT significantly improved survival of rats bearing 9L intracranial glioma compared with BB radiation therapy delivered at a comparable dose (P<.001); the efficacy of MRT and BB radiation therapy was similar when the MRT dose was half that of BB. The greater efficacy of MRT was not correlated with a difference in cell proliferation (Mki67 and proliferating cell nuclear antigen) or in transcriptomic stimulation of angiogenesis (vascular endothelial growth factor A or tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) but was correlated with a higher cell death rate (factor for apoptosis signals) and higher recruitment of macrophages (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 and CD68 transcripts) a few days after MRT. Conclusions: These results show the superiority of MRT over BB radiation therapy when applied at comparable doses, suggesting that spatial fractionation is responsible for a specific and particularly efficient tissue response. The higher induction of cell death and immune cell activation in brain tumors treated by MRT may be involved in such responses.
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Energy Technology Data Exchange (ETDEWEB)
Bouchet, Audrey, E-mail: audrey.m.bouchet@gmail.com [Université Grenoble Alpes, Grenoble Institut des Neurosciences, Grenoble (France); Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France); Bräuer-Krisch, Elke; Prezado, Yolanda [Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France); El Atifi, Michèle [Université Grenoble Alpes, Grenoble Institut des Neurosciences, Grenoble (France); Grenoble University Hospital, Grenoble (France); Rogalev, Léonid; Le Clec' h, Céline [Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France); Laissue, Jean Albert [University of Bern, Bern (Switzerland); Pelletier, Laurent, E-mail: laurent.pelletier@ujf-grenoble.fr [Université Grenoble Alpes, Grenoble Institut des Neurosciences, Grenoble (France); Grenoble University Hospital, Grenoble (France); Le Duc, Géraldine [Biomedical Beamline, European Synchrotron Radiation Facility, Grenoble (France)
2016-08-01
Purpose: Synchrotron microbeam radiation therapy (MRT) is based on the spatial fractionation of the incident, highly focused synchrotron beam into arrays of parallel microbeams, typically a few tens of microns wide and depositing several hundred grays. This irradiation modality was shown to have a high therapeutic impact on tumors, especially in intracranial locations. However, mechanisms responsible for such a property are not fully understood. Methods and Materials: Thanks to recent progress in dosimetry, we compared the effect of MRT and synchrotron broad beam (BB) radiation therapy delivered at comparable doses (equivalent to MRT valley dose) on tumor growth control and on classical radiobiological functions by histologic evaluation and/or transcriptomic analysis. Results: MRT significantly improved survival of rats bearing 9L intracranial glioma compared with BB radiation therapy delivered at a comparable dose (P<.001); the efficacy of MRT and BB radiation therapy was similar when the MRT dose was half that of BB. The greater efficacy of MRT was not correlated with a difference in cell proliferation (Mki67 and proliferating cell nuclear antigen) or in transcriptomic stimulation of angiogenesis (vascular endothelial growth factor A or tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 2) but was correlated with a higher cell death rate (factor for apoptosis signals) and higher recruitment of macrophages (tyrosine kinase with immunoglobulin-like and epidermal growth factor-like domains 1 and CD68 transcripts) a few days after MRT. Conclusions: These results show the superiority of MRT over BB radiation therapy when applied at comparable doses, suggesting that spatial fractionation is responsible for a specific and particularly efficient tissue response. The higher induction of cell death and immune cell activation in brain tumors treated by MRT may be involved in such responses.
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Influence of radiation therapy on T-lymphocyte subpopulations
International Nuclear Information System (INIS)
Job, G.
1984-01-01
The author claims this to be the first time where monoclonal antibodies are used in a long-term study in order to determine the influence of radiation therapy on T-lymphozyte-subpopulations in patients suffering from malignant growths. The influence of radiation therapy on B-cells, T-cells and macrophages was also checked. Two groups of patients were given two different radiation doses, and examined separately in order to discover possible effects of the dosage. Radiation therapy reduced B- and T-lymphocytes to the same degree as the total lymphozyte population so that their shares in percent remained unchanged. The same was also found for macrophages. Determination of clones and suppressor T-lymphozytes before, during and after radiation showed T-lymphozytes to have a higher resistance against the influence of radiation than clones. Suppressor cells also regenerated more quickly than clones after the end of the therapy. While radiation therapy was applied the clone/suppressor cell ratio dropped to values lower than those of the healthy reference group. After the end of the therapy this quotient dropped even further in some cases while in others it began to rise slowly, but even 6 months after the end of the therapy it was still lower than normal. As a number of diseases show an increased 'immunoregulatory quotient' it would be conceivable to influence this quotient with radiation therapy in order to achieve a therapeutic effect. (orig./MG) [de
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Mehta, Shahil; Gajjar, Shefali R; Padgett, Kyle R; Asher, David; Stoyanova, Radka; Ford, John C; Mellon, Eric A
2018-03-19
Radiation therapy (RT) plays a critical role in the treatment of glioblastoma. Studies of brain imaging during RT for glioblastoma have demonstrated changes in the brain during RT. However, frequent or daily utilization of standalone magnetic resonance imaging (MRI) scans during RT have limited feasibility. The recent release of the tri-cobalt-60 MRI-guided RT (MR-IGRT) device (ViewRay MRIdian, Cleveland, OH) allows for daily brain MRI for the RT setup. Daily MRI of three postoperative patients undergoing RT and temozolomide for glioblastoma over a six-week course allowed for the identification of changes to the cavity, edema, and visible tumor on a daily basis. The volumes and dimensions of the resection cavities, edema, and T2-hyperintense tumor were measured. A general trend of daily decreases in cavity measurements was observed in all patients. For the one patient with edema, a trend of daily increases followed by a trend of daily decreases were observed. These results suggest that daily MRI could be used for onboard resimulation and adaptive RT for future fluctuations in the sizes of brain tumors, cavities, or cystic components. This could improve tumor targeting and reduce RT of healthy brain tissue.
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External and internal radiation therapy: Past and future directions
Directory of Open Access Journals (Sweden)
Sadeghi Mahdi
2010-01-01
Full Text Available Cancer is a leading cause of morbidity and mortality in the modern world. Treatment modalities comprise radiation therapy, surgery, chemotherapy and hormonal therapy. Radiation therapy can be performed by using external or internal radiation therapy. However, each method has its unique properties which undertakes special role in cancer treatment, this question is brought up that: For cancer treatment, whether external radiation therapy is more efficient or internal radiation therapy one? To answer this question, we need to consider principles and structure of individual methods. In this review, principles and application of each method are considered and finally these two methods are compared with each other.
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SU-G-JeP2-08: Image-Guided Radiation Therapy Using Synthetic CTs in Brain Cancer
Energy Technology Data Exchange (ETDEWEB)
Price, R.G.; Glide-Hurst, C. [Wayne State School of Medicine, Detroit, MI (United States); Henry Ford Health System, Detroit, MI (United States); Kim, J.; Zheng, W.; Chetty, I.J. [Henry Ford Health System, Detroit, MI (United States)
2016-06-15
Purpose: Synthetic-CTs(synCTs) are essential for MR-only treatment planning. However, the performance of synCT for IGRT must be carefully assessed. This work evaluated the accuracy of synCT and synCT-generated DRRs and determined their performance for IGRT in brain cancer radiation therapy. Methods: MR-SIM and CT-SIM images were acquired of a novel anthropomorphic phantom and a cohort of 12 patients. SynCTs were generated by combining an ultra-short echo time (UTE) sequence with other MRI datasets using voxel-based weighted summation. For the phantom, DRRs from synCT and CT were compared via bounding box and landmark analysis. Planar (MV/KV) and volumetric (CBCT) IGRT performance were evaluated across several platforms. In patients, retrospective analysis was conducted to register CBCTs (n=34) to synCTs and CTs using automated rigid registration in the treatment planning system using whole brain and local registration techniques. A semi-automatic registration program was developed and validated to rigidly register planar MV/KV images (n=37) to synCT and CT DRRs. Registration reproducibility was assessed and margin differences were characterized using the van Herk formalism. Results: Bounding box and landmark analysis of phantom synCT DRRs were within 1mm of CT DRRs. Absolute 2D/2D registration shift differences ranged from 0.0–0.7mm for phantom DRRs on all treatment platforms and 0.0–0.4mm for volumetric registrations. For patient planar registrations, mean shift differences were 0.4±0.5mm (range: −0.6–1.6mm), 0.0±0.5mm, (range: −0.9–1.2mm), and 0.1±0.3mm (range: −0.7–0.6mm) for the superior-inferior(S-I), left-right(L–R), and anterior-posterior(A-P) axes, respectively. Mean shift differences in volumetric registrations were 0.6±0.4mm (range: −0.2–1.6mm), 0.2±0.4mm (range: −0.3–1.2mm), and 0.2±0.3mm (range: −0.2–1.2mm) for S-I, L–R, and A–P axes, respectively. CT-SIM and synCT derived margins were within 0.3mm. Conclusion
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SU-G-JeP2-08: Image-Guided Radiation Therapy Using Synthetic CTs in Brain Cancer
International Nuclear Information System (INIS)
Price, R.G.; Glide-Hurst, C.; Kim, J.; Zheng, W.; Chetty, I.J.
2016-01-01
Purpose: Synthetic-CTs(synCTs) are essential for MR-only treatment planning. However, the performance of synCT for IGRT must be carefully assessed. This work evaluated the accuracy of synCT and synCT-generated DRRs and determined their performance for IGRT in brain cancer radiation therapy. Methods: MR-SIM and CT-SIM images were acquired of a novel anthropomorphic phantom and a cohort of 12 patients. SynCTs were generated by combining an ultra-short echo time (UTE) sequence with other MRI datasets using voxel-based weighted summation. For the phantom, DRRs from synCT and CT were compared via bounding box and landmark analysis. Planar (MV/KV) and volumetric (CBCT) IGRT performance were evaluated across several platforms. In patients, retrospective analysis was conducted to register CBCTs (n=34) to synCTs and CTs using automated rigid registration in the treatment planning system using whole brain and local registration techniques. A semi-automatic registration program was developed and validated to rigidly register planar MV/KV images (n=37) to synCT and CT DRRs. Registration reproducibility was assessed and margin differences were characterized using the van Herk formalism. Results: Bounding box and landmark analysis of phantom synCT DRRs were within 1mm of CT DRRs. Absolute 2D/2D registration shift differences ranged from 0.0–0.7mm for phantom DRRs on all treatment platforms and 0.0–0.4mm for volumetric registrations. For patient planar registrations, mean shift differences were 0.4±0.5mm (range: −0.6–1.6mm), 0.0±0.5mm, (range: −0.9–1.2mm), and 0.1±0.3mm (range: −0.7–0.6mm) for the superior-inferior(S-I), left-right(L–R), and anterior-posterior(A-P) axes, respectively. Mean shift differences in volumetric registrations were 0.6±0.4mm (range: −0.2–1.6mm), 0.2±0.4mm (range: −0.3–1.2mm), and 0.2±0.3mm (range: −0.2–1.2mm) for S-I, L–R, and A–P axes, respectively. CT-SIM and synCT derived margins were within 0.3mm. Conclusion
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Modern radiation therapy for extranodal lymphomas
DEFF Research Database (Denmark)
Yahalom, Joachim; Illidge, Tim; Specht, Lena
2015-01-01
Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL...... and treatment planning for the most frequently involved organs. Specifically, detailed recommendations for RT volumes are provided. We have applied the same modern principles of involved site radiation therapy as previously developed and published as guidelines for Hodgkin lymphoma and nodal NHL. We have...... there is a lack of guidelines for the use of RT in the management of ENL. This report presents an effort by the International Lymphoma Radiation Oncology Group (ILROG) to harmonize and standardize the principles of treatment of ENL, and to address the technical challenges of simulation, volume definition...
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... can cause pain. Radiation given to shrink a tumor near the esophagus , which can interfere with a patient’s ability to eat and drink. How is radiation therapy planned for an individual ... show the location of a patient’s tumor and the normal areas around it. These scans ...
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International Nuclear Information System (INIS)
Liu Hui; Zhang Xu; Vinogradskiy, Yevgeniy Y.; Swisher, Stephen G.; Komaki, Ritsuko; Chang, Joe Y.
2012-01-01
Purpose: To determine the incidence of and risk factors for radiation pneumonitis (RP) after stereotactic ablative radiation therapy (SABR) to the lung in patients who had previously undergone conventional thoracic radiation therapy. Methods and Materials: Seventy-two patients who had previously received conventionally fractionated radiation therapy to the thorax were treated with SABR (50 Gy in 4 fractions) for recurrent disease or secondary parenchymal lung cancer (T 10 and mean lung dose (MLD) of the previous plan and the V 10 -V 40 and MLD of the composite plan were also related to RP. Multivariate analysis revealed that ECOG PS scores of 2-3 before SABR (P=.009), FEV1 ≤65% before SABR (P=.012), V 20 ≥30% of the composite plan (P=.021), and an initial PTV in the bilateral mediastinum (P=.025) were all associated with RP. Conclusions: We found that severe RP was relatively common, occurring in 20.8% of patients, and could be predicted by an ECOG PS score of 2-3, an FEV1 ≤65%, a previous PTV spanning the bilateral mediastinum, and V 20 ≥30% on composite (previous RT+SABR) plans. Prospective studies are needed to validate these predictors and the scoring system on which they are based.
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TH-F-202-00: MRI for Radiation Therapy
International Nuclear Information System (INIS)
2016-01-01
MRI has excellent soft tissue contrast and can provide both anatomical and physiological information. It is becoming increasingly important in radiation therapy for treatment planning, image-guided radiation therapy, and treatment assessment. It is critically important at this time point to educate and update our medical physicists about MRI to prepare for the upcoming surge of MRI applications in radiation therapy. This session will review important basics of MR physics, pulse sequence designs, and current radiotherapy application, as well as showcase exciting new developments in MRI that can be potentially useful in radiation therapy. Learning Objectives: To learn basics of MR physics and understand the differences between various pulse sequences To review current applications of MRI in radiation therapy.To discuss recent MRI advances for future MRI guided radiation therapy Partly supported by NIH (1R21CA165384).; W. Miller, Research supported in part by Siemens Healthcare; G. Li, My clinical research is in part supported by NIH U54CA137788. I have a collaborative research project with Philips Healthcare.; J. Cai, jing cai
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TH-F-202-00: MRI for Radiation Therapy
Energy Technology Data Exchange (ETDEWEB)
NONE
2016-06-15
MRI has excellent soft tissue contrast and can provide both anatomical and physiological information. It is becoming increasingly important in radiation therapy for treatment planning, image-guided radiation therapy, and treatment assessment. It is critically important at this time point to educate and update our medical physicists about MRI to prepare for the upcoming surge of MRI applications in radiation therapy. This session will review important basics of MR physics, pulse sequence designs, and current radiotherapy application, as well as showcase exciting new developments in MRI that can be potentially useful in radiation therapy. Learning Objectives: To learn basics of MR physics and understand the differences between various pulse sequences To review current applications of MRI in radiation therapy.To discuss recent MRI advances for future MRI guided radiation therapy Partly supported by NIH (1R21CA165384).; W. Miller, Research supported in part by Siemens Healthcare; G. Li, My clinical research is in part supported by NIH U54CA137788. I have a collaborative research project with Philips Healthcare.; J. Cai, jing cai.
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International Nuclear Information System (INIS)
Lamb, James M.; Agazaryan, Nzhde; Low, Daniel A.
2013-01-01
Purpose: To determine whether kilovoltage x-ray projection radiation therapy setup images could be used to perform patient identification and detect gross errors in patient setup using a computer algorithm. Methods and Materials: Three patient cohorts treated using a commercially available image guided radiation therapy (IGRT) system that uses 2-dimensional to 3-dimensional (2D-3D) image registration were retrospectively analyzed: a group of 100 cranial radiation therapy patients, a group of 100 prostate cancer patients, and a group of 83 patients treated for spinal lesions. The setup images were acquired using fixed in-room kilovoltage imaging systems. In the prostate and cranial patient groups, localizations using image registration were performed between computed tomography (CT) simulation images from radiation therapy planning and setup x-ray images corresponding both to the same patient and to different patients. For the spinal patients, localizations were performed to the correct vertebral body, and to an adjacent vertebral body, using planning CTs and setup x-ray images from the same patient. An image similarity measure used by the IGRT system image registration algorithm was extracted from the IGRT system log files and evaluated as a discriminant for error detection. Results: A threshold value of the similarity measure could be chosen to separate correct and incorrect patient matches and correct and incorrect vertebral body localizations with excellent accuracy for these patient cohorts. A 10-fold cross-validation using linear discriminant analysis yielded misclassification probabilities of 0.000, 0.0045, and 0.014 for the cranial, prostate, and spinal cases, respectively. Conclusions: An automated measure of the image similarity between x-ray setup images and corresponding planning CT images could be used to perform automated patient identification and detection of localization errors in radiation therapy treatments
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Energy Technology Data Exchange (ETDEWEB)
Lamb, James M., E-mail: jlamb@mednet.ucla.edu; Agazaryan, Nzhde; Low, Daniel A.
2013-10-01
Purpose: To determine whether kilovoltage x-ray projection radiation therapy setup images could be used to perform patient identification and detect gross errors in patient setup using a computer algorithm. Methods and Materials: Three patient cohorts treated using a commercially available image guided radiation therapy (IGRT) system that uses 2-dimensional to 3-dimensional (2D-3D) image registration were retrospectively analyzed: a group of 100 cranial radiation therapy patients, a group of 100 prostate cancer patients, and a group of 83 patients treated for spinal lesions. The setup images were acquired using fixed in-room kilovoltage imaging systems. In the prostate and cranial patient groups, localizations using image registration were performed between computed tomography (CT) simulation images from radiation therapy planning and setup x-ray images corresponding both to the same patient and to different patients. For the spinal patients, localizations were performed to the correct vertebral body, and to an adjacent vertebral body, using planning CTs and setup x-ray images from the same patient. An image similarity measure used by the IGRT system image registration algorithm was extracted from the IGRT system log files and evaluated as a discriminant for error detection. Results: A threshold value of the similarity measure could be chosen to separate correct and incorrect patient matches and correct and incorrect vertebral body localizations with excellent accuracy for these patient cohorts. A 10-fold cross-validation using linear discriminant analysis yielded misclassification probabilities of 0.000, 0.0045, and 0.014 for the cranial, prostate, and spinal cases, respectively. Conclusions: An automated measure of the image similarity between x-ray setup images and corresponding planning CT images could be used to perform automated patient identification and detection of localization errors in radiation therapy treatments.
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Lamb, James M; Agazaryan, Nzhde; Low, Daniel A
2013-10-01
To determine whether kilovoltage x-ray projection radiation therapy setup images could be used to perform patient identification and detect gross errors in patient setup using a computer algorithm. Three patient cohorts treated using a commercially available image guided radiation therapy (IGRT) system that uses 2-dimensional to 3-dimensional (2D-3D) image registration were retrospectively analyzed: a group of 100 cranial radiation therapy patients, a group of 100 prostate cancer patients, and a group of 83 patients treated for spinal lesions. The setup images were acquired using fixed in-room kilovoltage imaging systems. In the prostate and cranial patient groups, localizations using image registration were performed between computed tomography (CT) simulation images from radiation therapy planning and setup x-ray images corresponding both to the same patient and to different patients. For the spinal patients, localizations were performed to the correct vertebral body, and to an adjacent vertebral body, using planning CTs and setup x-ray images from the same patient. An image similarity measure used by the IGRT system image registration algorithm was extracted from the IGRT system log files and evaluated as a discriminant for error detection. A threshold value of the similarity measure could be chosen to separate correct and incorrect patient matches and correct and incorrect vertebral body localizations with excellent accuracy for these patient cohorts. A 10-fold cross-validation using linear discriminant analysis yielded misclassification probabilities of 0.000, 0.0045, and 0.014 for the cranial, prostate, and spinal cases, respectively. An automated measure of the image similarity between x-ray setup images and corresponding planning CT images could be used to perform automated patient identification and detection of localization errors in radiation therapy treatments. Copyright © 2013 Elsevier Inc. All rights reserved.
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Care of the patient receiving radiation therapy
Energy Technology Data Exchange (ETDEWEB)
Yasko, J.M.
1982-12-01
External radiation therapy, or teletherapy, is the use of ionizing radiation to destroy cancer cells. Clinical use of ionizing radiation as treatment for cancer began with the discovery of x-rays in 1895, the identification of natural radioactivity (radium) in 1896, and the first reported cure of cancer, a basal cell epithelioma, induced by radiation in 1899. Initially, radiation was administered as a single large dose and produced severe, life-threatening side effects. The basis for the use of ionizing radiation in daily increments for a period of weeks was provided by Regaud in 1922; ten years later, Coutard clinically developed the method of dose fractionation, which remains in use today. Although the use of ionizing radiation as a treatment is over eighty years old, only in recent years have advancements in its clinical application been based on research related to the biologic effect of radiation on human cells. To effectively care for the patient prior to, during, and at the completion of external radiation therapy, the nurse must know the physical and biologic basis of external radiation therapy and its clinical application.
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Care of the patient receiving radiation therapy
International Nuclear Information System (INIS)
Yasko, J.M.
1982-01-01
External radiation therapy, or teletherapy, is the use of ionizing radiation to destroy cancer cells. Clinical use of ionizing radiation as treatment for cancer began with the discovery of x-rays in 1895, the identification of natural radioactivity (radium) in 1896, and the first reported cure of cancer, a basal cell epithelioma, induced by radiation in 1899. Initially, radiation was administered as a single large dose and produced severe, life-threatening side effects. The basis for the use of ionizing radiation in daily increments for a period of weeks was provided by Regaud in 1922; ten years later, Coutard clinically developed the method of dose fractionation, which remains in use today. Although the use of ionizing radiation as a treatment is over eighty years old, only in recent years have advancements in its clinical application been based on research related to the biologic effect of radiation on human cells. To effectively care for the patient prior to, during, and at the completion of external radiation therapy, the nurse must know the physical and biologic basis of external radiation therapy and its clinical application
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Rancilio, Nicholas J; Custead, Michelle R; Poulson, Jean M
2016-09-01
A 5-year-old spayed female Shih Tzu was referred for evaluation of a nasal transitional carcinoma. A total lifetime dose of 117 Gy was delivered to the intranasal mass in three courses over nearly 2 years using fractionated intensity modulated radiation therapy (IMRT) to spare normal tissues. Clinically significant late normal tissue side effects were limited to bilaterally diminished tear production. The patient died of metastatic disease progression 694 days after completion of radiation therapy course 1. This case demonstrates that retreatment with radiation therapy to high lifetime doses for recurrent local disease may be well tolerated with IMRT. © 2016 American College of Veterinary Radiology.
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International Nuclear Information System (INIS)
Pommier, P.; Morelle, M.; Perrier, L.; Crevoisier, R. de; Laplanche, A.; Dudouet, P.; Mahe, M.A.; Supiot, S.; Chauvet, B.; Nguyen, T.D.; Crehange, G.; Zawadi, A.; Chapet, O.; Latorzeff, I.; Bossi, A.; Beckendorf, V.; Touboul, E.; Muracciole, X.; Bachaud, J.M.; Lagrange, J.L.
2012-01-01
Purpose. - The main objective of the economical study was to prospectively and randomly assess the additional costs of daily versus weekly patient positioning quality control in image-guided radiotherapy (IGRT), taking into account the modalities of the 3D-imaging: tomography (CBCT) or gold seeds implants. A secondary objective was to prospectively assess the additional costs of 3D versus 2D imaging with portal imaging for patient positioning controls. Patients and methods. - Economics data are issued from a multicenter randomized medico-economics trial comparing the two frequencies of patient positioning control during prostate IGRT. A prospective cohort with patient positioning control with PI (control group) was constituted for the cost comparison between 3D (IGRT) versus 2D imaging. The economical evaluation was focused to the radiotherapy direct costs, adopting the hospital's point of view and using a micro-costing method applied to the parameters that may lead to cost differences between evaluated strategies. Results. - The economical analysis included a total of 241 patients enrolled between 2007 and 2011 in seven centres, 183 in the randomized study (128 with CBCT and 55 with fiducial markers) and 58 in the control group. Compared to weekly controls, the average additional cost per patient of daily controls was euros 847 (CBCT) and euros 179 (markers). Compared to PI, the average additional cost per patient was euros 1392 (CBCT) and euros 997 (fiducial markers) for daily controls; euros 545 (CBCT) and euros 818 (markers) in case of weekly controls. Conclusion. - A daily frequency for image control in IGRT and 3D images patient positioning control (IGRT) for prostate cancer lead to significant additional cost compared to weekly control and 2D imaging (PI). Long-term clinical assessment will permit to assess the medico-economical ratio of these innovative radiotherapy modalities. (authors)
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Clinical applications of continuous infusion chemotherapy ahd concomitant radiation therapy
International Nuclear Information System (INIS)
Rosenthal, C.J.; Rotman, M.
1986-01-01
This book presents information on the following topics: theoretical basis and clinical applications of 5-FU as a radiosensitizer; treatment of hepatic metastases from gastro intestingal primaries with split course radiation therapy; combined modality therapy with 5-FU, Mitomycin-C and radiation therapy for sqamous cell cancers; treatment of bladder carcinoma with concomitant infusion chemotherapy and irradiation; a treatment of invasiv bladder cancer by the XRT/5FU protocol; concomitant radiation therapy and doxorubicin by continuous infusion in advanced malignancies; cis platin by continuous infusion with concurrent radiation therapy in malignant tumors; combination of radiation with concomitant continuous adriamycin infusion in a patient with partially excised pleomorphic soft tissue sarcoma of the lower extremeity; treatment of recurrent carcinoma of the paranasal sinuses using concomitant infusion cis-platinum and radiation therapy; hepatic artery infusion for hepatic metastases in combination with hepatic resection and hepatic radiation; study of simultaneous radiation therapy, continuous infusion, 5FU and bolus mitomycin-C; cancer of the esophagus; continuous infusion VP-16, bolus cis-platinum and simultaneous radiation therapy as salvage therapy in small cell bronchogenic carcinoma; and concomitant radiation, mitomycin-C and 5-FU infusion in gastro intestinal cancer
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Effect of radiation therapy against intracranial hemangiopericytoma
Energy Technology Data Exchange (ETDEWEB)
Uemura, Shozaburo; Kuratsu, Jun-ichi; Hamada, Jun-ichiro; Yoshioka, Susumu; Kochi, Masato; Ushio, Yukitaka [Kumamoto Univ. (Japan). School of Medicine; Nakahara, Tadashi; Kishida, Katsuaki
1992-06-01
Seven cases of intracranial hemangiopericytoma were studied retrospectively to investigate the efficacy of radiation therapy. Tumor response evaluated by computed tomography and magnetic resonance imaging was obvious after 20-30 Gy irradiation. The total reduction rate was 80-90% and continued as long as 5-7 months after treatment. In five patients receiving radiation therapy before radical removal, the tumors were easily removed without massive hemorrhage. Histological inspection of specimens after irradiation showed a significant disappearance of tumor cells. Pyknosis frequently occurred in endothelial cells, and proliferating vessels with hyalinoid degeneration were also seen. Reticulin fibers between tumor cells were fewer, split, or absent. Preoperative radiation therapy is useful in the treatment of hemangiopericytoma involving considerable surgical risk. Postoperative radiation therapy should be given even if removal is complete. (author).
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Effect of radiation therapy against intracranial hemangiopericytoma
International Nuclear Information System (INIS)
Uemura, Shozaburo; Kuratsu, Jun-ichi; Hamada, Jun-ichiro; Yoshioka, Susumu; Kochi, Masato; Ushio, Yukitaka; Nakahara, Tadashi; Kishida, Katsuaki.
1992-01-01
Seven cases of intracranial hemangiopericytoma were studied retrospectively to investigate the efficacy of radiation therapy. Tumor response evaluated by computed tomography and magnetic resonance imaging was obvious after 20-30 Gy irradiation. The total reduction rate was 80-90% and continued as long as 5-7 months after treatment. In five patients receiving radiation therapy before radical removal, the tumors were easily removed without massive hemorrhage. Histological inspection of specimens after irradiation showed a significant disappearance of tumor cells. Pyknosis frequently occurred in endothelial cells, and proliferating vessels with hyalinoid degeneration were also seen. Reticulin fibers between tumor cells were fewer, split, or absent. Preoperative radiation therapy is useful in the treatment of hemangiopericytoma involving considerable surgical risk. Postoperative radiation therapy should be given even if removal is complete. (author)
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1995-01-01
The aim of this book is to provide a uniquely comprehensive source of information on the entire field of radiation therapy physics. The very significant advances in imaging, computational, and accelerator technologies receive full consideration, as do such topics as the dosimetry of radiolabeled antibodies and dose calculation models. The scope of the book and the expertise of the authors make it essential reading for interested physicians and physicists and for radiation dosimetrists.
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Spatially weighted mutual information image registration for image guided radiation therapy
International Nuclear Information System (INIS)
Park, Samuel B.; Rhee, Frank C.; Monroe, James I.; Sohn, Jason W.
2010-01-01
Purpose: To develop a new metric for image registration that incorporates the (sub)pixelwise differential importance along spatial location and to demonstrate its application for image guided radiation therapy (IGRT). Methods: It is well known that rigid-body image registration with mutual information is dependent on the size and location of the image subset on which the alignment analysis is based [the designated region of interest (ROI)]. Therefore, careful review and manual adjustments of the resulting registration are frequently necessary. Although there were some investigations of weighted mutual information (WMI), these efforts could not apply the differential importance to a particular spatial location since WMI only applies the weight to the joint histogram space. The authors developed the spatially weighted mutual information (SWMI) metric by incorporating an adaptable weight function with spatial localization into mutual information. SWMI enables the user to apply the selected transform to medically ''important'' areas such as tumors and critical structures, so SWMI is neither dominated by, nor neglects the neighboring structures. Since SWMI can be utilized with any weight function form, the authors presented two examples of weight functions for IGRT application: A Gaussian-shaped weight function (GW) applied to a user-defined location and a structures-of-interest (SOI) based weight function. An image registration example using a synthesized 2D image is presented to illustrate the efficacy of SWMI. The convergence and feasibility of the registration method as applied to clinical imaging is illustrated by fusing a prostate treatment planning CT with a clinical cone beam CT (CBCT) image set acquired for patient alignment. Forty-one trials are run to test the speed of convergence. The authors also applied SWMI registration using two types of weight functions to two head and neck cases and a prostate case with clinically acquired CBCT/MVCT image sets. The
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Spatially weighted mutual information image registration for image guided radiation therapy.
Park, Samuel B; Rhee, Frank C; Monroe, James I; Sohn, Jason W
2010-09-01
To develop a new metric for image registration that incorporates the (sub)pixelwise differential importance along spatial location and to demonstrate its application for image guided radiation therapy (IGRT). It is well known that rigid-body image registration with mutual information is dependent on the size and location of the image subset on which the alignment analysis is based [the designated region of interest (ROI)]. Therefore, careful review and manual adjustments of the resulting registration are frequently necessary. Although there were some investigations of weighted mutual information (WMI), these efforts could not apply the differential importance to a particular spatial location since WMI only applies the weight to the joint histogram space. The authors developed the spatially weighted mutual information (SWMI) metric by incorporating an adaptable weight function with spatial localization into mutual information. SWMI enables the user to apply the selected transform to medically "important" areas such as tumors and critical structures, so SWMI is neither dominated by, nor neglects the neighboring structures. Since SWMI can be utilized with any weight function form, the authors presented two examples of weight functions for IGRT application: A Gaussian-shaped weight function (GW) applied to a user-defined location and a structures-of-interest (SOI) based weight function. An image registration example using a synthesized 2D image is presented to illustrate the efficacy of SWMI. The convergence and feasibility of the registration method as applied to clinical imaging is illustrated by fusing a prostate treatment planning CT with a clinical cone beam CT (CBCT) image set acquired for patient alignment. Forty-one trials are run to test the speed of convergence. The authors also applied SWMI registration using two types of weight functions to two head and neck cases and a prostate case with clinically acquired CBCT/ MVCT image sets. The SWMI registration with
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Modern radiation therapy for primary cutaneous lymphomas
DEFF Research Database (Denmark)
Specht, Lena; Dabaja, Bouthaina; Illidge, Tim
2015-01-01
Primary cutaneous lymphomas are a heterogeneous group of diseases. They often remain localized, and they generally have a more indolent course and a better prognosis than lymphomas in other locations. They are highly radiosensitive, and radiation therapy is an important part of the treatment......, either as the sole treatment or as part of a multimodality approach. Radiation therapy of primary cutaneous lymphomas requires the use of special techniques that form the focus of these guidelines. The International Lymphoma Radiation Oncology Group has developed these guidelines after multinational...... meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the International Lymphoma Radiation Oncology Group steering committee on the use of radiation therapy in primary cutaneous lymphomas in the modern era....
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Kim, Jung-In; Lee, Hanyoung; Wu, Hong-Gyun; Chie, Eui Kyu; Kang, Hyun-Cheol; Park, Jong Min
2017-09-01
The aim of this study is to develop a visual guidance patient-controlled (VG-PC) respiratory gating system for respiratory-gated magnetic-resonance image-guided radiation therapy (MR-IGRT) and to evaluate the performance of the developed system. The near-real-time cine planar MR image of a patient acquired during treatment was transmitted to a beam projector in the treatment room through an optical fiber cable. The beam projector projected the cine MR images inside the bore of the ViewRay system in order to be visible to a patient during treatment. With this visual information, patients voluntarily controlled their respiration to put the target volume into the gating boundary (gating window). The effect of the presence of the beam projector in the treatment room on the image quality of the MRI was investigated by evaluating the signal-to-noise ratio (SNR), uniformity, low-contrast detectability, high-contrast spatial resolution, and spatial integrity with the VG-PC gating system. To evaluate the performance of the developed system, we applied the VG-PC gating system to a total of seven patients; six patients received stereotactic ablative radiotherapy (SABR) and one patient received conventional fractionated radiation therapy. The projected cine MR images were visible even when the room light was on. No image data loss or additional time delay during delivery of image data were observed. Every indicator representing MRI quality, including SNR, uniformity, low-contrast detectability, high-contrast spatial resolution, and spatial integrity exhibited values higher than the tolerance levels of the manufacturer with the VG-PC gating system; therefore, the presence of the VG-PC gating system in the treatment room did not degrade the MR image quality. The average beam-off times due to respiratory gating with and without the VG-PC gating system were 830.3 ± 278.2 s and 1264.2 ± 302.1 s respectively (P = 0.005). Consequently, the total treatment times excluding
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Physics fundamentals and biological effects of synchrotron radiation therapy
International Nuclear Information System (INIS)
Prezado, Y.
2010-01-01
The main goal of radiation therapy is to deposit a curative dose in the tumor without exceeding the tolerances in the nearby healthy tissues. For some radioresistant tumors, like gliomas, requiring high doses for complete sterilization, the major obstacle for curative treatment with ionizing radiation remains the limited tolerance of the surrounding healthy tissue. This limitation is particularly severe for brain tumors and, especially important in children, due to the high risk of complications in the development of the central nervous system. In addition, the treatment of tumors close to an organ at risk, like the spinal cord, is also restricted. One possible solution is the development of new radiation therapy techniques exploiting radically different irradiation modes and modifying, in this way, the biological equivalent doses. This is the case of synchrotron radiation therapy (SRT). In this work the three new radiation therapy techniques under development at the European Synchrotron Radiation Facility (ESRF), in Grenoble (France) will be described, namely: synchrotron stereotactic radiation therapy (SSRT), microbeam radiation therapy (MRT) and minibeam radiation therapy. The promising results in the treatment of the high grade brain tumors obtained in preclinical studies have paved the way to the clinical trials. The first patients are expected in the fall of 2010. (Author).
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Radiation therapy and late reactions in normal tissues
International Nuclear Information System (INIS)
Aoyama, Takashi; Kuroda, Yasumasa
1998-01-01
Recent developments in cancer therapy have made us increasingly aware that the quality of life of a patient is as valuable as other benefits received from therapy. This awareness leads to an emphasis on organ and/or function preservation in the course of therapy. In line with this new thinking, greater consideration is placed on radiation therapy as an appropriate modality of cancer therapy. Possible complications in normal tissues, especially those of late reaction type after the therapy must be overcome. This review, therefore, focuses on recent progress of studies on mechanisms of the complications of the late reaction type. An observation of a clinical case concerning a late reaction of spinal cord (radiation myelopathy) and surveys of experimental studies on the mechanisms of late reactions (including radiation pneumonitis and lung fibrosis, and radiation response of vascular endothelial cells) provide a hypothesis that apoptosis through the pathway starting with radiation-induced sphingomyelin hydrolysis may play an important role in causing a variety of late reactions. This insight is based on the fact that radiation also activates protein kinase C which appears to block apoptosis. The mechanisms of late reactions, therefore, may involve a balance between radiation-induced apoptotic death and its down regulation by suppressor mechanisms through protein kinase C. (author)
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Selective use of adjuvant radiation therapy in resectable colorectal adenocarcinoma
International Nuclear Information System (INIS)
Cohen, A.M.; Gunderson, L.L.; Welch, C.E.
1981-01-01
Colorectal cancer recurs within the operative field in 10-20 per cent of patients undergoing potentially curative surgery. In certain subgroups, the recurrence rate is 20-50 per cent. There are some data to suggest either preoperative or postoperative radiation therapy as an adjuvant to potentially curative surgery can reduce the local operative failure rate. However, since radiation therapy has significant side effects, patient selection to maximize the therapeutic ratio is important. This report defines the criteria at the Massachusetts General Hospital for selection of patients with colorectal cancer for adjuvant radiation therapy, defines radiation therapy-surgery sequencing alternatives used, and describes techniques to reduce radiation side effects. Over a period of three and a half years, 196 patients received adjuvant radiation therapy: 51 patients received either moderate or low dose preoperative radiation therapy to rectal or rectosigmoid cancers, and 161 patients received postoperative radiation therapy to the pelvis or extrapelvic colonic tumor-lymph node beds. Some patients who received low-dose preoperative radiation therapy also received moderate-dose postoperative radiation therapy. We prefer moderate-dose postoperative radiation therapy as the approach most likely to decrease the local recurrence rate with minimal interference with surgical procedures and late small-bowel complications. Patients who received postoperative radiation therapy were those without distant metastases, whose primary tumor pathology revealed macroscopic or extensive microscopic transmural tumor penetration into extraperitoneal tissues. Careful case selection, multiple field techniques, the use of reperitonealization, omental flaps, and retroversion of the uterus into the pelvis were combined with postoperative small-bowel x-rays, bladder distention, and lateral portals to minimize radiation damage to normal structures
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Extramammary Paget's disease: role of radiation therapy
International Nuclear Information System (INIS)
Guerrieri, M.; Back, M.F.
2002-01-01
Extra mammary Paget's disease (EMPD) is an uncommon premalignant skin condition that has been traditionally managed with surgery. A report of long-standing Paget's disease with transformation to invasive adenocarcinoma definitively managed with radiation therapy is presented. A review of cases of extramammary Paget's disease treated with radiation therapy is discussed. The use of radiation therapy should be considered in selected cases, as these studies demonstrate acceptable rates of local control when used as an adjunct to surgery, or as a definitive treatment modality. Copyright (2002) Blackwell Science Pty Ltd
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Scalp Dose Evaluation According Radiation Therapy Technique of Whole Brain Radiation Therapy
International Nuclear Information System (INIS)
Jang, Joon Yung; Park, Soo Yun; Kim, Jong Sik; Choi, Byeong Gi; Song, Gi Won
2011-01-01
Opposing portal irradiation with helmet field shape that has been given to a patient with brain metastasis can cause excess dose in patient's scalp, resulting in hair loss. For this reason, this study is to quantitatively analyze scalp dose for effective prevention of hair loss by comparing opposing portal irradiation with scalp-shielding shape and tomotherapy designed to protect patient's scalp with conventional radiation therapy. Scalp dose was measured by using three therapies (HELMET, MLC, TOMO) after five thermo-luminescence dosimeters were positioned along center line of frontal lobe by using RANDO Phantom. Scalp dose and change in dose distribution were compared and analyzed with DVH after radiation therapy plan was made by using Radiation Treatment Planning System (Pinnacle3, Philips Medical System, USA) and 6 MV X-ray (Clinac 6EX, VARIAN, USA). When surface dose of scalp by using thermo-luminescence dosimeters was measured, it was revealed that scalp dose decreased by average 87.44% at each point in MLC technique and that scalp dose decreased by average 88.03% at each point in TOMO compared with HELMET field therapy. In addition, when percentage of volume (V95%, V100%, V105% of prescribed dose) was calculated by using Dose Volume Histogram (DVH) in order to evaluate the existence or nonexistence of hotspot in scalp as to three therapies (HELMET, MLC, TOMO), it was revealed that MLC technique and TOMO plan had good dose coverage and did not have hot spot. Reducing hair loss of a patient who receives whole brain radiotherapy treatment can make a contribution to improve life quality of the patient. It is expected that making good use of opposing portal irradiation with scalp-shielding shape and tomotherapy to protect scalp of a patient based on this study will reduce hair loss of a patient.
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Scalp Dose Evaluation According Radiation Therapy Technique of Whole Brain Radiation Therapy
Energy Technology Data Exchange (ETDEWEB)
Jang, Joon Yung; Park, Soo Yun; Kim, Jong Sik; Choi, Byeong Gi; Song, Gi Won [Dept. of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of)
2011-09-15
Opposing portal irradiation with helmet field shape that has been given to a patient with brain metastasis can cause excess dose in patient's scalp, resulting in hair loss. For this reason, this study is to quantitatively analyze scalp dose for effective prevention of hair loss by comparing opposing portal irradiation with scalp-shielding shape and tomotherapy designed to protect patient's scalp with conventional radiation therapy. Scalp dose was measured by using three therapies (HELMET, MLC, TOMO) after five thermo-luminescence dosimeters were positioned along center line of frontal lobe by using RANDO Phantom. Scalp dose and change in dose distribution were compared and analyzed with DVH after radiation therapy plan was made by using Radiation Treatment Planning System (Pinnacle3, Philips Medical System, USA) and 6 MV X-ray (Clinac 6EX, VARIAN, USA). When surface dose of scalp by using thermo-luminescence dosimeters was measured, it was revealed that scalp dose decreased by average 87.44% at each point in MLC technique and that scalp dose decreased by average 88.03% at each point in TOMO compared with HELMET field therapy. In addition, when percentage of volume (V95%, V100%, V105% of prescribed dose) was calculated by using Dose Volume Histogram (DVH) in order to evaluate the existence or nonexistence of hotspot in scalp as to three therapies (HELMET, MLC, TOMO), it was revealed that MLC technique and TOMO plan had good dose coverage and did not have hot spot. Reducing hair loss of a patient who receives whole brain radiotherapy treatment can make a contribution to improve life quality of the patient. It is expected that making good use of opposing portal irradiation with scalp-shielding shape and tomotherapy to protect scalp of a patient based on this study will reduce hair loss of a patient.
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Cancer of the larynx: radiation therapy. III
International Nuclear Information System (INIS)
Wang, C.C.
1976-01-01
Radiation therapy is the treatment of choice for a T1 and T2 tumor with normal cord mobility and/or an exophytic lesion. It not only provides excellent control of the disease, but also preserves a good, useful voice in approximately 90 percent of the irradiated patients. For a T2 lesion with impaired cord mobility and/or moderate ulceration, a trial course of radiotherapy is initially given. If the tumor shows good regression and/or a return of normal cord mobility after a dose of 4000 rads, radiation therapy may be continued to a curative dose level, about 6500 rads. Surgery is reserved for treating residual disease six to eight weeks after radiation therapy or for recurrence. A T3 lesion with complete cord fixation and/or deep ulceration with nodes does not respond favorably to radiation therapy, and a planned combination of irradiation and laryngectomy is advised. Disease that extends beyond the larynx, T4, is rarely curable by radiation therapy alone. If the lesion is still operable, a combined approach of radiation and surgery is preferred; if not, palliative radiation therapy is given. Lymph node metastases from laryngeal carcinoma indicate advanced disease and is managed by preoperative irradiation and radical neck dissection. Under a program of therapeutic individualization, two-thirds to three-quarters of patients with cancer of the larynx can be cured by irradiation with preservation of a good, useful voice. In the remainder, the larynx must be sacrificed to save the patient's life. The ultimate control of laryngeal cancer lies in eradicating the extensive primary lesion and metastatic nodes, a common problem in the management of squamous cell carcinoma elsewhere in the body
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Whole-brain radiation therapy for brain metastases: detrimental or beneficial?
International Nuclear Information System (INIS)
Gemici, Cengiz; Yaprak, Gokhan
2015-01-01
Stereotactic radiosurgery is frequently used, either alone or together with whole-brain radiation therapy to treat brain metastases from solid tumors. Certain experts and radiation oncology groups have proposed replacing whole-brain radiation therapy with stereotactic radiosurgery alone for the management of brain metastases. Although randomized trials have favored adding whole-brain radiation therapy to stereotactic radiosurgery for most end points, a recent meta-analysis demonstrated a survival disadvantage for patients treated with whole-brain radiation therapy and stereotactic radiosurgery compared with patients treated with stereotactic radiosurgery alone. However the apparent detrimental effect of adding whole-brain radiation therapy to stereotactic radiosurgery reported in this meta-analysis may be the result of inhomogeneous distribution of the patients with respect to tumor histologies, molecular histologic subtypes, and extracranial tumor stages between the groups rather than a real effect. Unfortunately, soon after this meta-analysis was published, even as an abstract, use of whole-brain radiation therapy in managing brain metastases has become controversial among radiation oncologists. The American Society of Radiation Oncology recently recommended, in their “Choose Wisely” campaign, against routinely adding whole-brain radiation therapy to stereotactic radiosurgery to treat brain metastases. However, this situation creates conflict for radiation oncologists who believe that there are enough high level of evidence for the effectiveness of whole-brain radiation therapy in the treatment of brain metastases
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Bienvenu, B; Cozon, G; Hoarau, C; Pasquet, M; Cherin, P; Clerson, P; Hachulla, E; Crave, J C; Delain, J C; Jaussaud, R
2016-06-22
IgG replacement therapy (IgRT) in primary immunodeficiencies (PID) is a lifelong treatment which may be administered intravenously (IVIg) or subcutaneously (SCIg), at hospital or at home. The objective of the VISAGE study was to investigate if route and/or place for IgRT impact patients' satisfaction regarding IgRT and quality of life (QoL) in real-life conditions. The study enrolled PID patients at least 15 years old receiving IgRT for at least 3 months. Satisfaction and QoL were evaluated at enrollment and over a 12-month follow-up period by Life Quality Index (LQI) which measures 3 dimensions of satisfaction: treatment interference, therapy related problems and therapy settings (factors I, II and III) and SF-36 v2 questionnaire. The study included 116 PID patients (mean age 42 ± 18 years, 44 % males, 58 % with scholar or professional occupation) receiving IgRT for a mean of 8.5 ± 8.4 years. At enrollment they were receiving either home-based SCIg (51 %), hospital-based IVIg (40 %) or home-based IVIg (9 %). Patients exhibited a high degree of satisfaction regarding IgRT whatever the route and place for administration. LQI factor I was higher for home-based SCIg (86 ± 2) than for hospital-based IVIg (81 ± 3) and home-based IVIg (73 ± 5; p = 0.02 versus home-based SCIg); no difference was found for LQI factor II; LQI factor III was higher for home-based SCIg (92 ± 2) than for hospital-based IVIg (87 ± 5) and hospital-based IVIg (82 ± 3; p = 0.005 versus home-based SCIg). By contrast, every dimension of QoL was impaired. Over the follow-up period, 10 patients switched from hospital-based IVIg to home-based SCIg and improved LQI factor I (p = 0.004) and factor III (p = 0.02), while no change was noticed in LQI factors II and QoL. Meanwhile, no change in satisfaction or QoL was found in patients with stable route of IgRT. When asked on their preferred place of treatment all but one patient with home
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Insufficiency fractures following radiation therapy for gynecologic malignancies
Energy Technology Data Exchange (ETDEWEB)
Ikushima, Hitoshi; Takegawa, Yoshihiro; Matsuki, Hirokazu; Yasuda, Hiroaki; Kawanaka, Takashi; Shiba, Atsushi; Kishida, Yoshiomi; Iwamoto, Seiji; Nishitani, Hiromu [Tokushima Univ. (Japan). School of Medicine
2002-12-01
The purpose of this study was to investigate the incidence, clinical and radiological findings of insufficiency fractures (IF) of the female pelvis following radiation therapy. We retrospectively reviewed the radiation oncology records of 108 patients with gynecologic malignancies who underwent external beam radiation therapy of the whole pelvis. All patients underwent conventional radiography and computed tomography (CT) scan every 6 months in follow-up after radiation therapy and magnetic resonance imaging (MRI) and radionuclide bone scan were added when the patients complained of pelvic pain. Thirteen of 108 patients (12%) developed IF in the irradiated field with a median interval of 6 months (range 3-51) from the completion of external beam radiation therapy. All patients who developed IF were postmenopausal women. Age of the patients who developed IF was significantly higher than that of the other patients. The parts of IF were sacroiliac joints, pubis, sacral body and 5th lumbar vertebra and six of 14 patients had multiple lesions. Treatment with rest and nonsteroidal anti-inflammatory drugs lead to symptomatic relief in all patients, although symptoms lasted from 3 to 20 months. Radiation-induced pelvic IF following radiation therapy for gynecologic malignancies were frequently observed in the post-menopausal patients within 1 year after external beam radiation therapy. Symmetrical fractures of the bilateral sacroiliac joint and pubis were the characteristic pattern of pelvic IF. All patients healed with conservative treatment, and nobody became non-ambulant. (author)
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International Nuclear Information System (INIS)
Webb, S.
1998-01-01
Intensity-modulated radiation therapy will make a quantum leap in tumor control. It is the new radiation therapy for the new millennium. The major methods to achieve IMRT are: 1. Dynamic multileaf collimator (DMLC) therapy, 2. multisegment therapy, and 3. tomotherapy. The principles of these 3 techniques are briefly reviewed. Each technique presents unique QA issues which are outlined. As an example this paper will present the results of a recent new study of an important QA concern in DMLC therapy. (orig.) [de
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International Nuclear Information System (INIS)
Mayyas, Essa; Chetty, Indrin J.; Chetvertkov, Mikhail; Wen, Ning; Neicu, Toni; Nurushev, Teamor; Ren Lei; Pradhan, Deepak; Movsas, Benjamin; Elshaikh, Mohamed A.; Lu Mei; Stricker, Hans
2013-01-01
Purpose: Setup errors and prostate intrafraction motion are main sources of localization uncertainty in prostate cancer radiation therapy. This study evaluates four different imaging modalities 3D ultrasound (US), kV planar images, cone-beam computed tomography (CBCT), and implanted electromagnetic transponders (Calypso/Varian) to assess inter- and intrafraction localization errors during intensity-modulated radiation therapy based treatment of prostate cancer. Methods: Twenty-seven prostate cancer patients were enrolled in a prospective IRB-approved study and treated to a total dose of 75.6 Gy (1.8 Gy/fraction). Overall, 1100 fractions were evaluated. For each fraction, treatment targets were localized using US, kV planar images, and CBCT in a sequence defined to determine setup offsets relative to the patient skin tattoos, intermodality differences, and residual errors for each patient and patient cohort. Planning margins, following van Herk's formalism, were estimated based on error distributions. Calypso-based localization was not available for the first eight patients, therefore centroid positions of implanted gold-seed markers imaged prior to and immediately following treatment were used as a motion surrogate during treatment. For the remaining 19 patients, Calypso transponders were used to assess prostate intrafraction motion. Results: The means (μ), and standard deviations (SD) of the systematic (Σ) and random errors (σ) of interfraction prostate shifts (relative to initial skin tattoo positioning), as evaluated using CBCT, kV, and US, averaged over all patients and fractions, were: [μ CBCT = (−1.2, 0.2, 1.1) mm, Σ CBCT = (3.0, 1.4, 2.4) mm, σ CBCT = (3.2, 2.2, 2.5) mm], [μ kV = (−2.9, −0.4, 0.5) mm, Σ kV = (3.4, 3.1, 2.6) mm, σ kV = (2.9, 2.0, 2.4) mm], and [μ US = (−3.6, −1.4, 0.0) mm, Σ US = (3.3, 3.5, 2.8) mm, σ US = (4.1, 3.8, 3.6) mm], in the anterior–posterior (A/P), superior–inferior (S/I), and the left–right (L
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Energy Technology Data Exchange (ETDEWEB)
Mayyas, Essa; Chetty, Indrin J.; Chetvertkov, Mikhail; Wen, Ning; Neicu, Toni; Nurushev, Teamor; Ren Lei; Pradhan, Deepak; Movsas, Benjamin; Elshaikh, Mohamed A. [Department of Radiation Oncology, Henry Ford Health System, 2799 West Grand Boulevard, Detroit, Michigan 48202 (United States); Lu Mei [Department of Public Health Sciences, Henry Ford Health System, 2799 West Grand Boulevard, Detroit Michigan 48202 (United States); Stricker, Hans [Department of Urology, Henry Ford Health System, 2799 West Grand Boulevard, Detroit Michigan 48202 (United States)
2013-04-15
Purpose: Setup errors and prostate intrafraction motion are main sources of localization uncertainty in prostate cancer radiation therapy. This study evaluates four different imaging modalities 3D ultrasound (US), kV planar images, cone-beam computed tomography (CBCT), and implanted electromagnetic transponders (Calypso/Varian) to assess inter- and intrafraction localization errors during intensity-modulated radiation therapy based treatment of prostate cancer. Methods: Twenty-seven prostate cancer patients were enrolled in a prospective IRB-approved study and treated to a total dose of 75.6 Gy (1.8 Gy/fraction). Overall, 1100 fractions were evaluated. For each fraction, treatment targets were localized using US, kV planar images, and CBCT in a sequence defined to determine setup offsets relative to the patient skin tattoos, intermodality differences, and residual errors for each patient and patient cohort. Planning margins, following van Herk's formalism, were estimated based on error distributions. Calypso-based localization was not available for the first eight patients, therefore centroid positions of implanted gold-seed markers imaged prior to and immediately following treatment were used as a motion surrogate during treatment. For the remaining 19 patients, Calypso transponders were used to assess prostate intrafraction motion. Results: The means ({mu}), and standard deviations (SD) of the systematic ({Sigma}) and random errors ({sigma}) of interfraction prostate shifts (relative to initial skin tattoo positioning), as evaluated using CBCT, kV, and US, averaged over all patients and fractions, were: [{mu}{sub CBCT}= (-1.2, 0.2, 1.1) mm, {Sigma}{sub CBCT}= (3.0, 1.4, 2.4) mm, {sigma}{sub CBCT}= (3.2, 2.2, 2.5) mm], [{mu}{sub kV}= (-2.9, -0.4, 0.5) mm, {Sigma}{sub kV}= (3.4, 3.1, 2.6) mm, {sigma}{sub kV}= (2.9, 2.0, 2.4) mm], and [{mu}{sub US}= (-3.6, -1.4, 0.0) mm, {Sigma}{sub US}= (3.3, 3.5, 2.8) mm, {sigma}{sub US}= (4.1, 3.8, 3.6) mm], in the anterior
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Gillan, Caitlin; Wiljer, David; Harnett, Nicole; Briggs, Kaleigh; Catton, Pamela
2010-11-01
The introduction of a transformative technology into practice settings can affect the functioning of interprofessional teams, placing stress on interprofessional relationships, thus slowing adoption and change. This study explored the potential of an interprofessional education (IPE) approach to mediate this stress and facilitate the adoption of a transformative technology- Image Guided Radiation Therapy (IGRT). Oncologists, physicists, and therapists in radiation medicine who attended an interprofessional IGRT Education Course were interviewed about perceived benefits and stressors to IPE and to interprofessional practice (IPP) in the IGRT context. A modified grounded theory approach was used to conduct 14 interviews, with 200 minutes of interview time recorded. In introducing IGRT, participants noted interprofessional stress in understanding and adopting new technology. IPE offered common terminology, appreciation for others' knowledge, and a holistic framework for practice. Outcomes were thought to foster collaboration, efficiency, and improved professional role definition. Time constraints and power relations were noted to be residual stressors exacerbated by IPE, but were thought to be transient. IPE can thus be of benefit in the implementation of transformative technologies such as IGRT, through mediation of interprofessional stress inherent in change. Interprofessional knowledge, collaboration, and efficiency in practice facilitate the development and adoption of a new practice model.
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Radiation therapy of Graves' ophthalmopathy. 2; Therapy started time
Energy Technology Data Exchange (ETDEWEB)
Kawamura, Toshinori; Koga, Sukehiko (Fujita Health Univ., Toyoake, Aichi (Japan). School of Medicine)
1994-04-01
The difference in the improvement of exophthalmos according to the period of starting radiation therapy was investigated for 26 patients of thyroid ophthalmopathy, also taking thyroidism during radiation into consideration. A 4 MV X-ray was used to a total dose of 20 Gy per 2 weeks. The treatment value tended to be better for the patients in whom the period from the appearance of exophthalmos in an euthyroid condition to the start of radiation was less than 12 months; those of a longer period showed poorer improvement. Radiation treatment of a hyperthyroid condition also showed poor results and it was thought it was not an adequately long enough period for the radiation to take effect. As a result, it was considered that the radiation therapy shall be advantageous if started within 12 months after the appearance of exophthalmos in an euthyroid condition. (author).
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Radiation therapy among atomic bomb survivors, Hiroshima and Nagasaki
International Nuclear Information System (INIS)
Pinkston, J.A.; Antoku, Shigetoshi; Russell, W.J.
1980-10-01
In the continuing evaluations of atomic bomb survivors for late radiation effects, not only doses from the A-bombs but those from other radiation sources must be considered, for the latter may be concomitantly acting factors causing bias among these investigations. In the present study, among 73 Hiroshima and 22 Nagasaki Adult Health Study (AHS) subjects who reported receiving radiation therapy, from 1970 through 1979, the medical records of 72 and 20, respectively, were reviewed, and 41 Hiroshima and 14 Nagasaki subjects were confirmed to have received radiation therapy. The data obtained in the present study were pooled with those of the previous investigation on radiation therapy exposures of AHS subjects prior to 1970. A total of 190 subjects have been documented as receiving radiation therapy and their doses were estimated. Energies used in treatments and diseases treated are discussed. Malignancies developed subsequent to radiation therapy in seven cases; five after treatment for malignancies and two after treatment for benign diseases. Neoplasms of 12 AHS subjects may have been induced by earlier radiation therapy; 5 in the earlier study and 7 in the present one. These investigations underscore the need for continued documentation of exposures to ionizing radiation for medical reasons, especially from sources incurring relatively high doses. Bias in assessments of late radiation effects among A-bomb survivors can thus be avoided. (author)
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A multiple model approach to respiratory motion prediction for real-time IGRT
International Nuclear Information System (INIS)
Putra, Devi; Haas, Olivier C L; Burnham, Keith J; Mills, John A
2008-01-01
Respiration induces significant movement of tumours in the vicinity of thoracic and abdominal structures. Real-time image-guided radiotherapy (IGRT) aims to adapt radiation delivery to tumour motion during irradiation. One of the main problems for achieving this objective is the presence of time lag between the acquisition of tumour position and the radiation delivery. Such time lag causes significant beam positioning errors and affects the dose coverage. A method to solve this problem is to employ an algorithm that is able to predict future tumour positions from available tumour position measurements. This paper presents a multiple model approach to respiratory-induced tumour motion prediction using the interacting multiple model (IMM) filter. A combination of two models, constant velocity (CV) and constant acceleration (CA), is used to capture respiratory-induced tumour motion. A Kalman filter is designed for each of the local models and the IMM filter is applied to combine the predictions of these Kalman filters for obtaining the predicted tumour position. The IMM filter, likewise the Kalman filter, is a recursive algorithm that is suitable for real-time applications. In addition, this paper proposes a confidence interval (CI) criterion to evaluate the performance of tumour motion prediction algorithms for IGRT. The proposed CI criterion provides a relevant measure for the prediction performance in terms of clinical applications and can be used to specify the margin to accommodate prediction errors. The prediction performance of the IMM filter has been evaluated using 110 traces of 4-minute free-breathing motion collected from 24 lung-cancer patients. The simulation study was carried out for prediction time 0.1-0.6 s with sampling rates 3, 5 and 10 Hz. It was found that the prediction of the IMM filter was consistently better than the prediction of the Kalman filter with the CV or CA model. There was no significant difference of prediction errors for the
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International Nuclear Information System (INIS)
Graff-Cailleaud, Pierre
2011-01-01
Numerous and exciting technological innovations were recently developed in radiotherapy. We aimed to assess benefits in two specific fields. 1) Clinical results of Intensity Modulated Radiotherapy (IMRT) applied to the treatment of Head and Neck (H and N) patients. The first study was a long-term mono-centric prospective registration of all H and N patients treated with IMRT in our institution. Locoregional control was excellent and toxicities limited. Recurrences were in-field. Dosimetric recommendations (parotids mean dose) were established. The second study assessed the impact of IMRT on health-related quality of life for H and N patients through a multicentric matched-pair comparison with conventional radiotherapy. Outstanding benefits were observed particularly in the fields of salivary dysfunction and oral discomfort. 2) Contribution of Image Guided Radiotherapy (IGRT) in the management of H and N patients treated with IMRT. The first study was a monitoring of delivered dose, using 3D dose recalculation from Megavoltage Cone-Beam CT (CBCT), as a quality assurance measure of a panel of H and N IMRT patients aligned with IGRT. Dosimetric consequences of anatomical changes were assessed. Contribution of color-coded MVCBCT dose-difference maps was studied. The aim of the second study was to quantify the inherent relative mobility between anatomic regions of the H and N area and to assess the dosimetric impact of several different matching procedures. Recommendations for the use of CBCT images in a daily practice were established. (author) [fr
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Energy Technology Data Exchange (ETDEWEB)
Park, J; Kim, J; Park, S [Seoul National University Hospital, Seoul (Korea, Republic of); Kim, S [Nuclear Safety and Security Commission, Seoul (Korea, Republic of); Shin, K [Seoul National University College of Medicine, Seoul (Korea, Republic of)
2016-06-15
Purpose: To investigate exposure outside the treatment field when treating breast cancer with tri-Co-60 magnetic resonance (MR) image guided radiation therapy (IGRT) system. Methods: A total of 7 patients who treated with accelerated partial breast irradiation (APBI) technique were selected prospectively for this study (prescription dose = 38.5 Gy in 10 fractions). Every patient treated with two plans, one was an initial plan and the other was an adaptive plan generated after finishing 5 fractions (a total of 14 plans). Every plan was calculated with and without magnetic field in the treatment planning system. The EBT3 films were attached on the front and the back of 1 cm bolus, and then it was placed on the patient body vertically to cover patient’s jaw and shoulder. After measurements, the maximum point dose and the mean dose of whole area of EBT3 film were acquired. Results: In the treatment plan with magnetic field, low dose stream outside the patient body was observed, almost reaching the patient’s jaw or shoulder, while it was not observed without magnetic field. The average values of the measured maximum and mean doses at the front of bolus were 30.1 ± 11.1 cGy (7.8% of the daily dose) and 14.7 ± 3.3 cGy (3.8%), respectively. At the back of bolus, those values were 6.0 ± 1.9 cGy (1.6%) and 5.1 ± 1.6 cGy (1.3%), respectively. The largest maximum dose at the front was 54.2 cGy (14.1%) while it was 20.7 cGy (5.4%) at the back. The average decrease of the maximum dose by the bolus was 24.0 ± 11.0 cGy. Conclusion: Due to magnetic field, dose stream outside the patient body can be generated during breast cancer treatment with the tri-Co-60 MR-IGRT system. Since this dose stream irradiated skin outside the treatment field, it should be shielded. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2015R1C1A1A01054192).
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Detoxication and antiproteolytic therapy of radiation complications
International Nuclear Information System (INIS)
Yakhontov, N.E.; Klimov, I.A.; Lavrikova, L.P.; Martynov, A.D.; Provorova, T.P.; Serdyukov, A.S.; Shestakov, A.F.
1984-01-01
49 patients with uterine cervix and ovarian carcinomas were treated with detoxication and antiproteolytic therapy of radiation-induced side-effects. The therapy permits to complete without interruption the remote gamma-therapy course and to reduce patients in-hospital periods by 10+- 1 days. The prescription of hemoder intravenous injection in a dose of 450 ml and contrical intramuscular injection (10000 AtrE) in cases of pronounced manifestations of radiation-induced side-effects (asthenia, leukopenia, enterocolitis) for 3 days should be considered an efficient therapy
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Radiation therapy in patients with hematologic diseases
International Nuclear Information System (INIS)
Hennequin, C.; Maylin, C.
1995-01-01
Radiation therapy has a significant place in the treatment of hematologic diseases. Irradiation is a key component of the treatment strategy for Hodgkin's disease and has benefited from clinical studies aimed at improving its therapeutic index. There have been many recent improvements, in particular with regard to accuracy of techniques, imagery, dosimetry, and implementation of quality-control procedures. In localized non-Hodgkin's lymphoma, the gold-standard treatment is radiation therapy coupled with a short course of chemotherapy. In contrast, the place of irradiation in disseminated lymphomas remains to be defined. Prophylactic irradiation of the brain is still used in patients with acute lymphoblastic leukemia. Radiation therapy is of value as palliative treatment of bone lesions of myeloma, in chemo-resistant lymphomas, and in relapses of leukemia. Total body irradiation is a cumbersome but irreplaceable method, which has also benefited from recent clinical and biological studies. Optimal radiation therapy with the best possible therapeutic index requires adequate technological and human resources. (authors). 30 refs., 1 tab
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Impact of radiation therapy on sexual life
International Nuclear Information System (INIS)
Leroy, T.; Gabelle Flandin, I.; Habold, D.; Hannoun-Levi, J.M.
2012-01-01
The aim of this study was to evaluate the impact of radiation therapy on sexual life. The analysis was based on a Pubmed literature review. The keywords used for this research were 'sexual, radiation, oncology, and cancer'. After a brief reminder on the anatomy and physiology, we explained the main complications of radiation oncology and their impact on sexual life. Preventive measures and therapeutic possibilities were discussed. Radiation therapy entails local, systematic and psychological after-effects. For women, vaginal stenosis and dyspareunia represent the most frequent side effects. For men, radiation therapy leads to erectile disorders for 25 to 75% of the patients. These complications have an echo often mattering on the patient quality of life of and on their sexual life post-treatment reconstruction. The knowledge of the indications and the various techniques of irradiation allow reducing its potential sexual morbidity. The information and the education of patients are essential, although often neglected. In conclusion, radiation therapy impacts in variable degrees on the sexual life of the patients. Currently, there are not enough preventive and therapeutic means. Patient information and the early screening of the sexual complications are at stake in the support of patients in the reconstruction of their sexual life. (authors)
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Once-Daily Radiation Therapy for Inflammatory Breast Cancer
International Nuclear Information System (INIS)
Brown, Lindsay; Harmsen, William; Blanchard, Miran; Goetz, Matthew; Jakub, James; Mutter, Robert; Petersen, Ivy; Rooney, Jessica; Stauder, Michael; Yan, Elizabeth; Laack, Nadia
2014-01-01
Purpose: Inflammatory breast cancer (IBC) is a rare and aggressive breast cancer variant treated with multimodality therapy. A variety of approaches intended to escalate the intensity and efficacy of radiation therapy have been reported, including twice-daily radiation therapy, dose escalation, and aggressive use of bolus. Herein, we examine our outcomes for patients treated with once-daily radiation therapy with aggressive bolus utilization, focusing on treatment technique. Methods and Materials: A retrospective review of patients with nonmetastatic IBC treated from January 1, 2000, through December 31, 2010, was performed. Locoregional control (LRC), disease-free survival (DFS), overall survival (OS) and predictors thereof were assessed. Results: Fifty-two women with IBC were identified, 49 (94%) of whom were treated with neoadjuvant chemotherapy. All underwent mastectomy followed by adjuvant radiation therapy. Radiation was delivered in once-daily fractions of 1.8 to 2.25 Gy (median, 2 Gy). Patients were typically treated with daily 1-cm bolus throughout treatment, and 33 (63%) received a subsequent boost to the mastectomy scar. Five-year Kaplan Meier survival estimates for LRC, DFS, and OS were 81%, 56%, and 64%, respectively. Locoregional recurrence was associated with poorer OS (P<.001; hazard ratio [HR], 4.1). Extracapsular extension was associated with worse LRC (P=.02), DFS (P=.007), and OS (P=.002). Age greater than 50 years was associated with better DFS (P=.03). Pathologic complete response was associated with a trend toward improved LRC (P=.06). Conclusions: Once-daily radiation therapy with aggressive use of bolus for IBC results in outcomes consistent with previous reports using various intensified radiation therapy regimens. LRC remains a challenge despite modern systemic therapy. Extracapsular extension, age ≤50 years, and lack of complete response to chemotherapy appear to be associated with worse outcomes. Novel strategies are needed in IBC
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Targeted Radiation Therapy for Cancer Initiative
2017-11-01
AWARD NUMBER: W81XWH-08-2-0174 TITLE: Targeted Radiation Therapy for Cancer Initiative PRINCIPAL INVESTIGATOR: Dusten Macdonald, MD...for Cancer Initiative 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Dusten Macdonald, MD 5d. PROJECT NUMBER...Cancer Initiative Final Report INTRODUCTION: The full potential of radiation therapy has not been realized due to the inability to locate and
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Pommier, P; Morelle, M; Perrier, L; de Crevoisier, R; Laplanche, A; Dudouet, P; Mahé, M-A; Chauvet, B; Nguyen, T-D; Créhange, G; Zawadi, A; Chapet, O; Latorzeff, I; Bossi, A; Beckendorf, V; Touboul, E; Muracciole, X; Bachaud, J-M; Supiot, S; Lagrange, J-L
2012-09-01
The main objective of the economical study was to prospectively and randomly assess the additional costs of daily versus weekly patient positioning quality control in image-guided radiotherapy (IGRT), taking into account the modalities of the 3D-imaging: tomography (CBCT) or gold seeds implants. A secondary objective was to prospectively assess the additional costs of 3D versus 2D imaging with portal imaging for patient positioning controls. Economics data are issued from a multicenter randomized medico-economics trial comparing the two frequencies of patient positioning control during prostate IGRT. A prospective cohort with patient positioning control with PI (control group) was constituted for the cost comparison between 3D (IGRT) versus 2D imaging. The economical evaluation was focused to the radiotherapy direct costs, adopting the hospital's point of view and using a microcosting method applied to the parameters that may lead to cost differences between evaluated strategies. The economical analysis included a total of 241 patients enrolled between 2007 and 2011 in seven centres, 183 in the randomized study (128 with CBCT and 55 with fiducial markers) and 58 in the control group. Compared to weekly controls, the average additional cost per patient of daily controls was €847 (CBCT) and €179 (markers). Compared to PI, the average additional cost per patient was €1392 (CBCT) and €997 (fiducial markers) for daily controls; €545 (CBCT) and €818 (markers) in case of weekly controls. A daily frequency for image control in IGRT and 3D images patient positioning control (IGRT) for prostate cancer lead to significant additional cost compared to weekly control and 2D imaging (PI). Long-term clinical assessment will permit to assess the medico-economical ratio of these innovative radiotherapy modalities. Copyright © 2012 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.
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DEFF Research Database (Denmark)
Jeppesen, Stefan Starup; Schytte, Tine; Jensen, Henrik R
2013-01-01
Abstract Introduction. Stereotactic body radiation therapy (SBRT) for early stage non-small cell lung cancer (NSCLC) is now an accepted and patient friendly treatment, but still controversy exists about its comparability to conventional radiation therapy (RT). The purpose of this single...... and SBRT predicted improved prognosis. However, staging procedure, confirmation procedure of recurrence and technical improvements of radiation treatment is likely to influence outcomes. However, SBRT seems to be as efficient as conventional RT and is a more convenient treatment for the patients....
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Intensity-modulated radiation therapy.
Goffman, Thomas E; Glatstein, Eli
2002-07-01
Intensity-modulated radiation therapy (IMRT) is an increasingly popular technical means of tightly focusing the radiation dose around a cancer. As with stereotactic radiotherapy, IMRT uses multiple fields and angles to converge on the target. The potential for total dose escalation and for escalation of daily fraction size to the gross cancer is exciting. The excitement, however, has greatly overshadowed a range of radiobiological and clinical concerns.
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XVII International Conference on the Use of Computers in Radiation Therapy (ICCR 2013)
2014-03-01
Editorial Dear colleagues, From a professional perspective there is nothing quite as enjoyable as attending a good conference with colleagues that share not only interest for the same topic but also a similar vision for their field of work. Proceedings cannot replace the direct contact and lively conversations between participants who are at the same time at the same place sharing ideas and discussion. However, proceedings complement the actual conference by 1. giving the ideas, research findings and debates which characterise the conference lasting presence 2. giving participants an opportunity to refresh their memory about issues they would like to follow up on and 3. providing an opportunity for others who were not able to attend the meeting to share in the thoughts and issues discussed at the conference. For the proceedings of the International Conferences on the Use of Computers in Radiation Therapy (ICCR) all this has been important in the past as the high citation rates for ICCR proceedings show. We hope that also the present proceedings will appeal to participants and others who are interested in cancer and ways to treat patients affected by it. It is exciting to note that what sounded like a small niche field (''Computers in Radiation Therapy'') has become a very broad forum to discuss all aspects of cancer diagnosis and therapy. Of particular interest for the 17th ICCR have been data and how to collect, organise and use it effectively. This is relevant for most areas in medicine and we believe that radiation therapy with its focus on evidence based practice and measurable and standardised activities has an important and possibly leading role to play. The 100 manuscripts combined in the present proceedings can hopefully contribute to this. The proceedings are organised into five different streams which reflect the foci of the conference: • Dose Calculation • Imaging for treatment planning and Motion Management • Treatment planning and optimisation
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Modern role and issues of radiation therapy for benign diseases
International Nuclear Information System (INIS)
Miyashita, Tsuguhiro; Tateno, Atsushi; Kumazaki, Tatsuo
1999-01-01
Cases of radiation therapy for benign diseases have diminished in number because of recent alternative methods and knowledge about radiation carcinogenesis. In contrast to this tendency, our cases of benign diseases have recently increased. The facts made us reconsider today's radiation therapy of benign diseases. We reviewed 349 patients who were diagnosed as having benign tumors or non-neoplastic conditions and treated by radiation therapy in the past sixteen years. Analyzed items were the annual transition of treatment number, sorts of diseases, patients' age and sex, and the goal of therapy. Of all radiation therapy patients, benign diseases account for 9.26%. The annual percentages were 0.5%, 6.0%, 11.2% and 13.7% at intervals of five years since 1982. The majority was 246 post-operative irradiation for keloids (71%) and 41 pituitary adenomas (12%). Compared with malignant tumors, benign disease patients were statistically younger and female-dominant. Applications of radiation therapy in keloids and pituitary adenomas had definite goals, but were unclear in other rare diseases. Benign diseases should be treated by radiation therapy as the second or third option, provided the patients have serious symptoms and their diseases do not respond to other modalities. It seems to be widely accepted that favorite cases such as keloids and pituitary adenomas are treated by radiation therapy. But, optimal radiation therapies for other rare benign diseases have not been established. Therefore, the building of databases on radiation therapy on benign diseases should be pursued. Since benign disease patients were young and female-dominant and had many remaining years, their carcinogenicity potential should be considered. (author)
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Energy Technology Data Exchange (ETDEWEB)
Uematsu, Minoru (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology Dept. of Radiology, National Defense Medical College, Saitama (Japan)); Kondo, Makoto (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Hiramatsu, Hideko (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Ikeda, Yasuo (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Hematology); Mikata, Sumio (Chiba Univ. (Japan). School of Medicine); Katayama, Michiaki (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Ito, Hisao (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Kusano, Shoichi (Dept. of Radiology, National Defense Medical College, Saitama (Japan)); Kubo, Asuchishi (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology)
1993-01-01
Seventeen patients with stage IA non-Hodgkin's lymphoma of the Waldeyer's ring were treated with radiation therapy with or without chemotherapy. All lesions were judged as having intermediate grade malignancy in the Working Formulation. Eight patients received combined treatment with three cycles of cylcophosphamide, doxorubicin, vincristine and prednison (CHOP) and radiation therapy with 30 to 40 Gy. Another 9 patients were treated with radiation therapy 40 to 60 Gy alone. After a median follow-up of 69 months, all 8 patients, treated with combined modality were alive and relapse-free whereas 4 of the 9 treated with irradiation alone had relapsed. All relapses occurred transdiaphragmatically. Two of the 4 relapsing patients were saved, but the other two died of the disease. The 5-year relapse-free and cause-specific survival rates were 100% and 100% in the combined modality group, and 56% and 76% in the radiation therapy alone group (relapse-free: p=0.04, cause-specific: p=0.16). There were no serious complications related to treatment, although most patients complained of mouth dryness and most patients given CHOP had paresthesia. Our opinion was that the total impact of these two side-effects on quality of life was less pronounced after combined modality than after radiation therapy alone. Limited chemotherapy and radiation therapy seemed to be more beneficial than radiation therapy alone not only in relapse-free survival but also in quality of life after treatment. (orig.).
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CT follow-up after radiation therapy for pituitary adenomas
International Nuclear Information System (INIS)
Rush, S.C.; Newall, J.
1988-01-01
Between 1973 and 1985, 105 patients received radiation therapy as all or part of their treatment for pituitary tumor at the New York University Medical Center. Of these, 48 patients underwent computed tomography (CT) at a minimum of 2 years following treatment, with detailed reports available for analysis of tumor regression. There were 28 men with a median age of 46 years (range, 18-71 years) and 20 women with a median age of 53 years (range, 28-80 years). Tumors were classified as secretory in 23 patients, nonsecretory in 21, and undetermined in four. Sixteen patients were treated with radiation therapy alone, 23 patients with surgery and radiation therapy, and the other with bromocriptine and radiation therapy, with or without surgery. With a median follow-up of 5 years (range, 2-14 years), 16 patients developed an empty sella, 25 patients had residual sellar mass, and seven patients had persistent extrasellar components or no change in their intrasellar mass. Among patients who did not have hypopituitarism at the inception of radiation therapy, five of 13 with empty sellas and 12 of 22 with residual mass subsequently required therapy. The authors conclude that residual mass is commonly found in long-term follow-up after radiation therapy, that isolated imaging studies revealing such findings after treatment in no way herald a diagnosis of recurrence, and that hypopituitarism following pituitary radiation therapy does not correlate with the ablation or persistence of tissue within the sella
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Radiation therapy for hypopharyngeal carcinoma. Impact of fractionation on treatment outcome
International Nuclear Information System (INIS)
Niibe, Yuzuru; Karasawa, Katsuyuki; Igaki, Hiroshi; Miyashita, Hisao; Tanaka, Yoshiaki
2003-01-01
The purpose of the current study was to evaluate the impact of fractionation on the treatment outcome of radiation therapy for hypopharyngeal carcinoma. Thirty-six inoperable or operation-refused hypopharyngeal patients were treated with curative-intended radiation therapy between 1976 and May 2001. Seventeen patients were treated with conventional radiation therapy, 1.8-2.0 Gy per fraction, totaling 64.0 Gy (conventional fractionation (CF) group), and 19 were treated with hyperfractionated radiation therapy, 1.2 Gy per fraction, totaling 74.4 Gy (hyperfractionation (HF) group). The radiation response of the two groups at the end of radiation therapy was almost the same. However, the 2-year local control rates of the HF and CF groups were 59.0% and 26.1% (p=0.012), respectively, a statistically significant differences. Moreover, multivariate analysis showed that HF was an independent prognostic factor for local control. Hyperfractionated radiation therapy was superior to conventional radiation therapy for local control. Local control of hypopharyngeal carcinoma correlated with laryngeal preservation, suggesting that hyperfractionated radiation therapy for hypopharyngeal carcinoma could be beneficial for patient quality of life (QOL). (author)
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State of the art of radiation therapy for esophageal cancer
International Nuclear Information System (INIS)
Itasaka, Satoshi
2014-01-01
Radiation therapy has a critical role in the treatment of esophageal cancer. To improve the treatment outcome of radiotherapy, not only strengthening the treatment intensity but also decreasing the long term toxicity is needed. To reduce the long term cardiopulmonary toxicity of chemoradiation, JCOG is now running a clinical trial which combines three dimensional conformal radiation therapy (3D-CRT) and mild irradiation dose. New techniques of radiation therapy, such as intensity modulated radiation therapy (IMRT) or particle therapy are also promising in both treatment intensity and decreased toxicity. (author)
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Nursing care update: Internal radiation therapy
International Nuclear Information System (INIS)
Lowdermilk, D.L.
1990-01-01
Internal radiation therapy has been used in treating gynecological cancers for over 100 years. A variety of radioactive sources are currently used alone and in combination with other cancer treatments. Nurses need to be able to provide safe, comprehensive care to patients receiving internal radiation therapy while using precautions to keep the risks of exposure to a minimum. This article discusses current trends and issues related to such treatment for gynecological cancers.20 references
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International Nuclear Information System (INIS)
Hu, Yanle; Rankine, Leith; Green, Olga L.; Kashani, Rojano; Li, H. Harold; Li, Hua; Rodriguez, Vivian; Santanam, Lakshmi; Wooten, H. Omar; Mutic, Sasa; Nana, Roger; Shvartsman, Shmaryu; Victoria, James; Dempsey, James F.
2015-01-01
Purpose: To characterize the performance of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy (MR-IGRT) system. Methods: The imaging performance characterization included four components: ACR (the American College of Radiology) phantom test, spatial integrity, coil signal to noise ratio (SNR) and uniformity, and magnetic field homogeneity. The ACR phantom test was performed in accordance with the ACR phantom test guidance. The spatial integrity test was evaluated using a 40.8 × 40.8 × 40.8 cm 3 spatial integrity phantom. MR and computed tomography (CT) images of the phantom were acquired and coregistered. Objects were identified around the surfaces of 20 and 35 cm diameters of spherical volume (DSVs) on both the MR and CT images. Geometric distortion was quantified using deviation in object location between the MR and CT images. The coil SNR test was performed according to the national electrical manufacturers association (NEMA) standards MS-1 and MS-9. The magnetic field homogeneity test was measured using field camera and spectral peak methods. Results: For the ACR tests, the slice position error was less than 0.10 cm, the slice thickness error was less than 0.05 cm, the resolved high-contrast spatial resolution was 0.09 cm, the resolved low-contrast spokes were more than 25, the image intensity uniformity was above 93%, and the percentage ghosting was less than 0.22%. All were within the ACR recommended specifications. The maximum geometric distortions within the 20 and 35 cm DSVs were 0.10 and 0.18 cm for high spatial resolution three-dimensional images and 0.08 and 0.20 cm for high temporal resolution two dimensional cine images based on the distance-to-phantom-center method. The average SNR was 12.0 for the body coil, 42.9 for the combined torso coil, and 44.0 for the combined head and neck coil. Magnetic field homogeneities at gantry angles of 0°, 30°, 60°, 90°, and 120° were 23.55, 20.43, 18.76, 19
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International Nuclear Information System (INIS)
Niibe, Hideo
1998-01-01
Estimations suggest that about 60% of all cancer patients will require some form of radiation therapy during their lifetime. Although 40 to 50% of cancer patients in Europe and the United States receive radiation therapy, only about 20% of patients with cancer in Japan undergo such treatment. This is largely due to the lack of understanding of the role of radiation therapy by many medical personnel in Japan, as well as to ''''radiation allergy'''' among many of the general population in Japan, a country that has been undergone atomic bombing. From our perspective as specialists in radiation therapy, the chronic shortage of radiation oncologist also poses a serious problem. Although there are approximately 700 hospitals throughout Japan where radiation therapy is available, no more than half this number of medical facilities have a full-time radiation oncologist. Perhaps the reason for this is that radiation therapy is perceived as unnecessary in Japan. However, it is absolutely essential. In our experience, the 5-year relative survival rate of patients with malignant tumors who have undergone radiation therapy in our clinic is 65 percent. Thus, radiation therapy has proven very useful in the treatment of malignant tumors. Moreover, better estimates of prognosis of cancer patients treated with radiation therapy are becoming possible. This article discusses the role of radiation therapy, from a radiation pathological perspective, in a multidisciplinary approach to treatment of cancer patients. I also emphasize the critical importance of training radiation oncologists who can function as part of multidisciplinary teams that care for patients with malignant tumors. (author). 50 refs
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Auger radiation targeted into DNA: a therapy perspective
Energy Technology Data Exchange (ETDEWEB)
Buchegger, Franz [University Hospital of Lausanne CHUV, Service of Nuclear Medicine, Lausanne (Switzerland); University Hospital of Lausanne, Service of Nuclear Medicine, Lausanne (Switzerland); Perillo-Adamer, Florence; Bischof Delaloye, Angelika [University Hospital of Lausanne CHUV, Service of Nuclear Medicine, Lausanne (Switzerland); Dupertuis, Yves M. [University Hospital of Geneva, Service of Nutrition, Geneva (Switzerland)
2006-11-15
Auger electron emitters that can be targeted into DNA of tumour cells represent an attractive systemic radiation therapy goal. In the situation of DNA-associated decay, the high linear energy transfer (LET) of Auger electrons gives a high relative biological efficacy similar to that of {alpha} particles. In contrast to {alpha} radiation, however, Auger radiation is of low toxicity when decaying outside the cell nucleus, as in cytoplasm or outside cells during blood transport. The challenge for such therapies is the requirement to target a high percentage of all cancer cells. An overview of Auger radiation therapy approaches of the past decade shows several research directions and various targeting vehicles. The latter include hormones, peptides, halogenated nucleotides, oligonucleotides and internalising antibodies. Here, we will discuss the basic principles of Auger electron therapy as compared with vector-guided {alpha} and {beta} radiation. We also review some radioprotection issues and briefly present the main advantages and disadvantages of the different targeting modalities that are under investigation. (orig.)
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Auger radiation targeted into DNA: a therapy perspective
International Nuclear Information System (INIS)
Buchegger, Franz; Perillo-Adamer, Florence; Bischof Delaloye, Angelika; Dupertuis, Yves M.
2006-01-01
Auger electron emitters that can be targeted into DNA of tumour cells represent an attractive systemic radiation therapy goal. In the situation of DNA-associated decay, the high linear energy transfer (LET) of Auger electrons gives a high relative biological efficacy similar to that of α particles. In contrast to α radiation, however, Auger radiation is of low toxicity when decaying outside the cell nucleus, as in cytoplasm or outside cells during blood transport. The challenge for such therapies is the requirement to target a high percentage of all cancer cells. An overview of Auger radiation therapy approaches of the past decade shows several research directions and various targeting vehicles. The latter include hormones, peptides, halogenated nucleotides, oligonucleotides and internalising antibodies. Here, we will discuss the basic principles of Auger electron therapy as compared with vector-guided α and β radiation. We also review some radioprotection issues and briefly present the main advantages and disadvantages of the different targeting modalities that are under investigation. (orig.)
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Breast conservation therapy for breast cancer. Radiation oncologist's point of view
International Nuclear Information System (INIS)
Hiraoka, Masahiro; Mitsumori, Michihide; Kokubo, Masaki; Fujishiro, Satsuki
1998-01-01
The roles and problems of radiation therapy in breast conserving therapy for breast cancer were presented. The roles of radiation therapy include decrease in breast recurrence, an alternative to axillary dissection for N0 cases, and neo-adjuvant radiation therapy. On the other hand, problems associated with radiation therapy are question of using radiation therapy for all cases, complications and worsening of cosmetics, and relatively high breast recurrence rates for margin-positive cases. The concept of breast conserving therapy is to improve QOL without decreasing treatment outcomes. It is considered that we should be more concentrated on the aspects of QOL because treatment outcomes of breast conserving therapy in Japan demonstrated sofar appear excellent. (author)
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Missed Radiation Therapy and Cancer Recurrence
Patients who miss radiation therapy sessions during cancer treatment have an increased risk of their disease returning, even if they eventually complete their course of radiation treatment, according to a new study.
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21 CFR 892.5050 - Medical charged-particle radiation therapy system.
2010-04-01
...-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy system... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical charged-particle radiation therapy system... equipment, patient and equipment supports, treatment planning computer programs, component parts, and...
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Energy Technology Data Exchange (ETDEWEB)
Valicenti, Richard K., E-mail: Richard.valicenti@ucdmc.ucdavis.edu [Department of Radiation Oncology, University of California, Davis School of Medicine, Davis, California (United States); Thompson, Ian [Department of Urology, University of Texas Health Science Center at San Antonio, San Antonio, Texas (United States); Albertsen, Peter [Division of Urology, University of Connecticut Health Center, Farmington, Connecticut (United States); Davis, Brian J. [Department of Radiation Oncology, Mayo Medical School, Rochester, Minnesota (United States); Goldenberg, S. Larry [Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia (Canada); Wolf, J. Stuart [Department of Urology, University of Michigan, Ann Arbor, Michigan (United States); Sartor, Oliver [Department of Medicine and Urology, Tulane Medical School, New Orleans, Louisiana (United States); Klein, Eric [Glickman Urological Kidney Institute, Cleveland Clinic, Cleveland, Ohio (United States); Hahn, Carol [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Michalski, Jeff [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri (United States); Roach, Mack [Department of Radiation Oncology, University of California, San Francisco, San Francisco, California (United States); Faraday, Martha M. [Four Oaks, Inc (United States)
2013-08-01
Purpose: The purpose of this guideline was to provide a clinical framework for the use of radiation therapy after radical prostatectomy as adjuvant or salvage therapy. Methods and Materials: A systematic literature review using PubMed, Embase, and Cochrane database was conducted to identify peer-reviewed publications relevant to the use of radiation therapy after prostatectomy. The review yielded 294 articles; these publications were used to create the evidence-based guideline statements. Additional guidance is provided as Clinical Principles when insufficient evidence existed. Results: Guideline statements are provided for patient counseling, use of radiation therapy in the adjuvant and salvage contexts, defining biochemical recurrence, and conducting a restaging evaluation. Conclusions: Physicians should offer adjuvant radiation therapy to patients with adverse pathologic findings at prostatectomy (ie, seminal vesicle invastion, positive surgical margins, extraprostatic extension) and salvage radiation therapy to patients with prostate-specific antigen (PSA) or local recurrence after prostatectomy in whom there is no evidence of distant metastatic disease. The offer of radiation therapy should be made in the context of a thoughtful discussion of possible short- and long-term side effects of radiation therapy as well as the potential benefits of preventing recurrence. The decision to administer radiation therapy should be made by the patient and the multidisciplinary treatment team with full consideration of the patient's history, values, preferences, quality of life, and functional status. The American Society for Radiation Oncology and American Urological Association websites show this guideline in its entirety, including the full literature review.
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International Nuclear Information System (INIS)
Valicenti, Richard K.; Thompson, Ian; Albertsen, Peter; Davis, Brian J.; Goldenberg, S. Larry; Wolf, J. Stuart; Sartor, Oliver; Klein, Eric; Hahn, Carol; Michalski, Jeff; Roach, Mack; Faraday, Martha M.
2013-01-01
Purpose: The purpose of this guideline was to provide a clinical framework for the use of radiation therapy after radical prostatectomy as adjuvant or salvage therapy. Methods and Materials: A systematic literature review using PubMed, Embase, and Cochrane database was conducted to identify peer-reviewed publications relevant to the use of radiation therapy after prostatectomy. The review yielded 294 articles; these publications were used to create the evidence-based guideline statements. Additional guidance is provided as Clinical Principles when insufficient evidence existed. Results: Guideline statements are provided for patient counseling, use of radiation therapy in the adjuvant and salvage contexts, defining biochemical recurrence, and conducting a restaging evaluation. Conclusions: Physicians should offer adjuvant radiation therapy to patients with adverse pathologic findings at prostatectomy (ie, seminal vesicle invastion, positive surgical margins, extraprostatic extension) and salvage radiation therapy to patients with prostate-specific antigen (PSA) or local recurrence after prostatectomy in whom there is no evidence of distant metastatic disease. The offer of radiation therapy should be made in the context of a thoughtful discussion of possible short- and long-term side effects of radiation therapy as well as the potential benefits of preventing recurrence. The decision to administer radiation therapy should be made by the patient and the multidisciplinary treatment team with full consideration of the patient's history, values, preferences, quality of life, and functional status. The American Society for Radiation Oncology and American Urological Association websites show this guideline in its entirety, including the full literature review
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Thyroid dysfunction after radiation therapy to the neck
International Nuclear Information System (INIS)
Soejima, Toshinori; Hirota, Saeko; Obayashi, Kayoko; Takada, Yoshiki; Kimura, Shuji; Yoshida, Shoji.
1993-01-01
The effects of radiation on the thyroid were investigated in 102 patients treated by radiation therapy to the neck. All patients had radiation ports which included the thyroid gland. Serum thyroid stimulating hormone (TSH) levels were elevated in 41 cases and the cumulative elevation rate was 52.1% in 5 years. The high frequency of elevated serum TSH levels observed in patients whose thyroid glands were included within the radiation fields (74.1%) was statistically significant compared to those whose thyroid glands were only partially included (23.4%). Among the patients whose entire thyroid glands were included within the radiation field, combination with chemotherapy increased the frequency of elevated serum TSH levels, but the increase was not statistically significant. Among 36 laryngeal cancer patients treated by only radiation therapy through a portal encompassing part of the thyroid, 4 (14%) were found to have elevated serum TSH levels. We advocate routine monitoring of thyroid functions after radiation therapy to the neck. (author)
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Impaired skin integrity related to radiation therapy
International Nuclear Information System (INIS)
Ratliff, C.
1990-01-01
Skin reactions associated with radiation therapy require frequent nursing assessment and intervention. Preventive interventions and early management can minimize the severity of the skin reaction. With the understanding of the pathogenesis of radiation skin reactions, the ET nurse can determine who is at risk and then implement preventive measures. Because radiation treatment is fractionated, skin reactions do not usually occur until midway through the course of therapy and will subside within a few weeks after completion of radiation. Many patients and their families still fear that radiation causes severe burns. Teaching and anticipatory guidance by the ET nurse is needed to assist patients and their families to overcome this fear, and to educate them on preventive skin care regimens
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Technological progress in radiation therapy for brain tumors
LENUS (Irish Health Repository)
Vernimmen, Frederik Jozef
2014-01-01
To achieve a good therapeutic ratio the radiation dose to the tumor should be as high as possible with the lowest possible dose to the surrounding normal tissue. This is especially the case for brain tumors. Technological ad- vancements in diagnostic imaging, dose calculations, and radiation delivery systems, combined with a better un- derstanding of the pathophysiology of brain tumors have led to improvements in the therapeutic results. The widely used technology of delivering 3-D conformal therapy with photon beams (gamma rays) produced by Li-near Accelerators has progressed into the use of Intensity modulated radiation therapy (IMRT). Particle beams have been used for several decades for radiotherapy because of their favorable depth dose characteristics. The introduction of clinically dedicated proton beam therapy facilities has improved the access for cancer patients to this treatment. Proton therapy is of particular interest for pediatric malignancies. These technical improvements are further enhanced by the evolution in tumor physiology imaging which allows for improved delineation of the tumor. This in turn opens the potential to adjust the radiation dose to maximize the radiobiological effects. The advances in both imaging and radiation therapy delivery will be discussed.
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Prostate Cancer (Radiation Therapy)
... be considered carefully, balancing the advantages against the disadvantages as they relate to the individual man's age, ... therapy with photon or x-rays: Uses advanced technology to tailor the x-ray or photon radiation ...
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Radiation therapy among A-bomb survivors, Hiroshima and Nagasaki
Energy Technology Data Exchange (ETDEWEB)
Russell, W J; Antoku, S
1971-01-01
The hospitals and clinics responsible for radiation therapy reported by ABCC-JNIH Adult Health Study subjects were surveyed to confirm treatment and estimate doses they received. Of 426 cases, 137 were documented by hospital records. Their ABCC medical records were also reviewed for pertinent clinical information. Excluding the cases not verified because of unavailability of records, confirmation rates were 0.46 in Hiroshima and 0.67 in Nagasaki. Radiation therapy doses according to date of treatment, diagnosis, body site, and source of exposure are included. These data are recorded routinely for future reference, along with doses from diagnostic roentgenology for evaluating overall ionizing radiation exposure of A-bomb survivors and their comparison subjects. Radiation therapy by source and by lesion treated is included. There were three cases with malignancies possibly related to their earlier radiation therapy. One was an A-bomb survivor with lung cancer previously reported as due to ionizing radiation from the A-bomb. Radiation therapy she received for breast cancer 11 years earlier was more likely the cause of the lung lesion than was her relatively small A-bomb dose. The importance of recording all diagnostic and therapeutic radiation, especially that received by those under continuing surveillance for late A-bomb effects, is stressed. (auth)
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Planning guide for radiologic installations. fascicle 1 -- radiation therapy installations
International Nuclear Information System (INIS)
Tuddenham, W.J.
1976-01-01
Five articles dealing with the development and operation of radiation therapy facilities present recommendations for the design of various types of radiation therapy facilities, including the university center, the free-standing private oncology center, and the community hospital radiation therapy department. Different concepts of department design are represented. In one article, the planning room is conceived to be the central feature of a facility; in another article, radiation therapy is designed around examination rooms. Shielding requirements are also discussed, as are the advantages and space and licensing requirements of various types of equipment. There is a need for planning appropriate computer facilities in conjunction with other equipment plans, and a critique of one radiation therapy unit is provided. The concept of a regional network for the delivery of radiation therapy services is then explored. The volume contains extensive illustrations in the form of floor plans, drawings, figures, and tables. Many of the articles include a bibliography. This is the first in a series of publications on radiation department design which will be useful to architects, engineers, and hospital planners
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DEFF Research Database (Denmark)
Schneider, Sergej; Jølck, Rasmus Irming; Troost, Esther Gera Cornelia
2018-01-01
Purpose: X-ray-based position verification of the target volume in image-guided radiation therapy (IGRT) of patients with pancreatic ductal adenocarcinoma (PDAC) is currently performed on solid fiducial markers that are implanted under endoscopic ultrasonography. A new biodegradable liquid fiduci...
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Molecular image guided radiation therapy-MIGRT in radiobioluminescence and nanoradioguidance
International Nuclear Information System (INIS)
Rao, V.L. Papineni
2014-01-01
Accurate dose delivery to malignant tissue in radiotherapy is essential for enhancing the treatment efficacy while minimizing morbidity of surrounding normal tissues. Advances in therapeutic strategies and diagnosis technologies along with our understanding of the biology of tumor response to radiation therapy have paved way to allow nearly 60% of current cancer patients to be treated with Radiation Therapy. The confluence of molecular imaging and nanotechnology fields are bridging physics and medicine and are quickly making strides in opening new avenues and therapeutic strategies that complement radiation therapy - with a distinct footprint in immunotherapy, adoptive cell therapy, and targeted chemotherapy. Incorporating optical imaging in radiation therapy in my laboratory, endogenous bioluminescence resulting from whole body irradiation in different organs, and in different animals, which is distinct from the Cherenkov radiation. The endogenous bioluminescence in response to irradiation is coined recently as radiobioluminescence. Thus with the necessity, the design, construction, and validation of Molecular Image Guided Radiation Therapy (MIGRT) instrumentation for preclinical theragnostics is carried out
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Energy Technology Data Exchange (ETDEWEB)
Acharya, Sahaja; Fischer-Valuck, Benjamin W.; Mazur, Thomas R.; Curcuru, Austen; Sona, Karl; Kashani, Rojano; Green, Olga; Ochoa, Laura; Mutic, Sasa; Zoberi, Imran; Li, H. Harold; Thomas, Maria A., E-mail: mthomas@radonc.wustl.edu
2016-11-15
Purpose: To use magnetic resonance image guided radiation therapy (MR-IGRT) for accelerated partial-breast irradiation (APBI) to (1) determine intrafractional motion of the breast surgical cavity; and (2) assess delivered dose versus planned dose. Methods and Materials: Thirty women with breast cancer (stages 0-I) who underwent breast-conserving surgery were enrolled in a prospective registry evaluating APBI using a 0.35-T MR-IGRT system. Clinical target volume was defined as the surgical cavity plus a 1-cm margin (excluding chest wall, pectoral muscles, and 5 mm from skin). No additional margin was added for the planning target volume (PTV). A volumetric MR image was acquired before each fraction, and patients were set up to the surgical cavity as visualized on MR imaging. To determine the delivered dose for each fraction, the electron density map and contours from the computed tomography simulation were transferred to the pretreatment MR image via rigid registration. Intrafractional motion of the surgical cavity was determined by applying a tracking algorithm to the cavity contour as visualized on cine MR. Results: Median PTV volume was reduced by 52% when using no PTV margin compared with a 1-cm PTV margin used conventionally. The mean (± standard deviation) difference between planned and delivered dose to the PTV (V95) was 0.6% ± 0.1%. The mean cavity displacement in the anterior–posterior and superior–inferior directions was 0.6 ± 0.4 mm and 0.6 ± 0.3 mm, respectively. The mean margin required for at least 90% of the cavity to be contained by the margin for 90% of the time was 0.7 mm (5th-95th percentile: 0-2.7 mm). Conclusion: Minimal intrafractional motion was observed, and the mean difference between planned and delivered dose was less than 1%. Assessment of efficacy and cosmesis of this MR-guided APBI approach is under way.
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Advanced Small Animal Conformal Radiation Therapy Device.
Sharma, Sunil; Narayanasamy, Ganesh; Przybyla, Beata; Webber, Jessica; Boerma, Marjan; Clarkson, Richard; Moros, Eduardo G; Corry, Peter M; Griffin, Robert J
2017-02-01
We have developed a small animal conformal radiation therapy device that provides a degree of geometrical/anatomical targeting comparable to what is achievable in a commercial animal irradiator. small animal conformal radiation therapy device is capable of producing precise and accurate conformal delivery of radiation to target as well as for imaging small animals. The small animal conformal radiation therapy device uses an X-ray tube, a robotic animal position system, and a digital imager. The system is in a steel enclosure with adequate lead shielding following National Council on Radiation Protection and Measurements 49 guidelines and verified with Geiger-Mueller survey meter. The X-ray source is calibrated following AAPM TG-61 specifications and mounted at 101.6 cm from the floor, which is a primary barrier. The X-ray tube is mounted on a custom-made "gantry" and has a special collimating assembly system that allows field size between 0.5 mm and 20 cm at isocenter. Three-dimensional imaging can be performed to aid target localization using the same X-ray source at custom settings and an in-house reconstruction software. The small animal conformal radiation therapy device thus provides an excellent integrated system to promote translational research in radiation oncology in an academic laboratory. The purpose of this article is to review shielding and dosimetric measurement and highlight a few successful studies that have been performed to date with our system. In addition, an example of new data from an in vivo rat model of breast cancer is presented in which spatially fractionated radiation alone and in combination with thermal ablation was applied and the therapeutic benefit examined.
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Combined use of Dexa-Scheroson and Primobolan-Depot in radiation therapy
Energy Technology Data Exchange (ETDEWEB)
Nagai, J [Shizuoka Rosai Hospital (Japan)
1976-05-01
Dexa-Scheroson and Primobolan-Depot were used together with radiation therapy (Linac therapy) required in 13 cases. The following results were obtained. The decrease in white cell counts, which often occurs in radiation therapy, was inhibited by the drugs. There was no case in which radiation therapy should necessarily withdraw because the number of leuckocytes was decreased to less than 3,000. The patients whose liver function was poor should be treated with both drugs at the beginning of radiation therapy. It was found that the combined use of the drugs is effective in the prevention and the treatment of cerebral edema in radiation therapy of intracranial lesion.
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Treatment of Recurrent Chordomas by Percutaneous Ethanol Injection Therapy and Radiation Therapy
International Nuclear Information System (INIS)
Nakajo, M.; Ohkubo, K.; Fukukura, Y.; Nandate, T.; Nakajo, M.
2006-01-01
We report a case of recurrent sacral chordomas that have been successfully controlled by the combination therapy of percutaneous ethanol injection therapy (PEIT) and radiation therapy in a 71-year-old man. PEIT may be one of the adjuvant therapies for recurrent chordomas
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Prototype demonstration of radiation therapy planning code system
International Nuclear Information System (INIS)
Little, R.C.; Adams, K.J.; Estes, G.P.; Hughes, L.S. III; Waters, L.S.
1996-01-01
This is the final report of a one-year, Laboratory-Directed Research and Development project at the Los Alamos National Laboratory (LANL). Radiation therapy planning is the process by which a radiation oncologist plans a treatment protocol for a patient preparing to undergo radiation therapy. The objective is to develop a protocol that delivers sufficient radiation dose to the entire tumor volume, while minimizing dose to healthy tissue. Radiation therapy planning, as currently practiced in the field, suffers from inaccuracies made in modeling patient anatomy and radiation transport. This project investigated the ability to automatically model patient-specific, three-dimensional (3-D) geometries in advanced Los Alamos radiation transport codes (such as MCNP), and to efficiently generate accurate radiation dose profiles in these geometries via sophisticated physics modeling. Modem scientific visualization techniques were utilized. The long-term goal is that such a system could be used by a non-expert in a distributed computing environment to help plan the treatment protocol for any candidate radiation source. The improved accuracy offered by such a system promises increased efficacy and reduced costs for this important aspect of health care
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TU-A-201-01: Introduction to In-Room Imaging System Characteristics
Energy Technology Data Exchange (ETDEWEB)
Chang, J. [Northwell Health (United States)
2016-06-15
Recent years have seen a widespread proliferation of available in-room image guidance systems for radiation therapy target localization with many centers having multiple in-room options. In this session, available imaging systems for in-room IGRT will be reviewed highlighting the main differences in workflow efficiency, targeting accuracy and image quality as it relates to target visualization. Decision-making strategies for integrating these tools into clinical image guidance protocols that are tailored to specific disease sites like H&N, lung, pelvis, and spine SBRT will be discussed. Learning Objectives: Major system characteristics of a wide range of available in-room imaging systems for IGRT. Advantages / disadvantages of different systems for site-specific IGRT considerations. Concepts of targeting accuracy and time efficiency in designing clinical imaging protocols.
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TU-A-201-00: Image Guidance Technologies and Management Strategies
Energy Technology Data Exchange (ETDEWEB)
NONE
2016-06-15
Recent years have seen a widespread proliferation of available in-room image guidance systems for radiation therapy target localization with many centers having multiple in-room options. In this session, available imaging systems for in-room IGRT will be reviewed highlighting the main differences in workflow efficiency, targeting accuracy and image quality as it relates to target visualization. Decision-making strategies for integrating these tools into clinical image guidance protocols that are tailored to specific disease sites like H&N, lung, pelvis, and spine SBRT will be discussed. Learning Objectives: Major system characteristics of a wide range of available in-room imaging systems for IGRT. Advantages / disadvantages of different systems for site-specific IGRT considerations. Concepts of targeting accuracy and time efficiency in designing clinical imaging protocols.
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Influence of radiation therapy on oral Candida albicans colonization: a quantitative assessment
International Nuclear Information System (INIS)
Rossie, K.M.; Taylor, J.; Beck, F.M.; Hodgson, S.E.; Blozis, G.G.
1987-01-01
An increase in quantity of oral Candida albicans was documented in patients receiving head and neck radiation therapy during and after therapy, as assessed by an oral-rinse culturing technique. The amount of the increase was greater in denture wearers and directly related to increasing radiation dose and increasing volume of parotid gland included in the radiation portal. A significant number of patients who did not carry C. albicans prior to radiation therapy developed positive cultures by 1 month after radiation therapy. The percentage of patients receiving head and neck radiation therapy who carried C. albicans prior to radiation therapy did not differ significantly from matched dental patient controls
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Late complications of radiation therapy
Energy Technology Data Exchange (ETDEWEB)
Masaki, Norie [Osaka Prefectural Center for Adult Diseases (Japan)
1998-03-01
There are cases in which, although all traces of acute radiation complications seem to have disappeared, late complications may appear months or years to become apparent. Trauma, infection or chemotherapy may sometimes recall radiation damage and irreversible change. There were two cases of breast cancer that received an estimated skin dose in the 6000 cGy range followed by extirpation of the residual tumor. The one (12 y.o.) developed atrophy of the breast and severe teleangiectasis 18 years later radiotherapy. The other one (42 y.o.) developed severe skin necrosis twenty years later radiotherapy after administration of chemotherapy and received skin graft. A case (52 y.o.) of adenoidcystic carcinoma of the trachea received radiation therapy. The field included the thoracic spinal cord which received 6800 cGy. Two years and 8 months after radiation therapy she developed complete paraplegia and died 5 years later. A truly successful therapeutic outcome requires that the patient be alive, cured and free of significant treatment-related morbidity. As such, it is important to assess quality of life in long-term survivors of cancer treatment. (author)
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Late complications of radiation therapy
International Nuclear Information System (INIS)
Masaki, Norie
1998-01-01
There are cases in which, although all traces of acute radiation complications seem to have disappeared, late complications may appear months or years to become apparent. Trauma, infection or chemotherapy may sometimes recall radiation damage and irreversible change. There were two cases of breast cancer that received an estimated skin dose in the 6000 cGy range followed by extirpation of the residual tumor. The one (12 y.o.) developed atrophy of the breast and severe teleangiectasis 18 years later radiotherapy. The other one (42 y.o.) developed severe skin necrosis twenty years later radiotherapy after administration of chemotherapy and received skin graft. A case (52 y.o.) of adenoidcystic carcinoma of the trachea received radiation therapy. The field included the thoracic spinal cord which received 6800 cGy. Two years and 8 months after radiation therapy she developed complete paraplegia and died 5 years later. A truly successful therapeutic outcome requires that the patient be alive, cured and free of significant treatment-related morbidity. As such, it is important to assess quality of life in long-term survivors of cancer treatment. (author)
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21 CFR 892.5300 - Medical neutron radiation therapy system.
2010-04-01
... therapy system. (a) Identification. A medical neutron radiation therapy system is a device intended to... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical neutron radiation therapy system. 892.5300... analysis and display equipment, patient and equipment support, treatment planning computer programs...
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Development of local radiation therapy
Energy Technology Data Exchange (ETDEWEB)
Lee, Seung Hoon; Lim, Sang Moo; Choi, Chang Woon; Chai, Jong Su; Kim, Eun Hee; Kim, Mi Sook; Yoo, Seong Yul; Cho, Chul Koo; Lee, Yong Sik; Lee, Hyun Moo
1999-04-01
The major limitations of radiation therapy for cancer are the low effectiveness of low LET and inevitable normal tissue damage. Boron Neutron Capture Therapy (BNCT) is a form of potent radiation therapy using Boron-10 having a high propensityof capturing theraml neutrons from nuclear reactor and reacting with a prompt nuclear reaction. Photodynamic therapy is a similiar treatment of modality to BNCT using tumor-seeking photosenistizer and LASER beam. If Boron-10 and photosensitizers are introduced selectively into tumor cells, it is theoretically possible to destroy the tumor and to spare the surrounding normal tissue. Therefore, BNCT and PDT will be new potent treatment modalities in the next century. In this project, we performed PDT in the patients with bladder cancers, oropharyngeal cancer, and skin cancers. Also we developed I-BPA, new porphyrin compounds, methods for estimation of radiobiological effect of neutron beam, and superficial animal brain tumor model. Furthermore, we prepared preclinical procedures for clinical application of BNCT, such as the macro- and microscopic dosimetry, obtaining thermal neutron flux from device used for fast neutron production in KCCH have been performed.
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Development of local radiation therapy
International Nuclear Information System (INIS)
Lee, Seung Hoon; Lim, Sang Moo; Choi, Chang Woon; Chai, Jong Su; Kim, Eun Hee; Kim, Mi Sook; Yoo, Seong Yul; Cho, Chul Koo; Lee, Yong Sik; Lee, Hyun Moo
1999-04-01
The major limitations of radiation therapy for cancer are the low effectiveness of low LET and inevitable normal tissue damage. Boron Neutron Capture Therapy (BNCT) is a form of potent radiation therapy using Boron-10 having a high propensityof capturing theraml neutrons from nuclear reactor and reacting with a prompt nuclear reaction. Photodynamic therapy is a similiar treatment of modality to BNCT using tumor-seeking photosenistizer and LASER beam. If Boron-10 and photosensitizers are introduced selectively into tumor cells, it is theoretically possible to destroy the tumor and to spare the surrounding normal tissue. Therefore, BNCT and PDT will be new potent treatment modalities in the next century. In this project, we performed PDT in the patients with bladder cancers, oropharyngeal cancer, and skin cancers. Also we developed I-BPA, new porphyrin compounds, methods for estimation of radiobiological effect of neutron beam, and superficial animal brain tumor model. Furthermore, we prepared preclinical procedures for clinical application of BNCT, such as the macro- and microscopic dosimetry, obtaining thermal neutron flux from device used for fast neutron production in KCCH have been performed
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Thyroid neoplasia following radiation therapy for Hodgkin's lymphoma
International Nuclear Information System (INIS)
McHenry, C.; Jarosz, H.; Calandra, D.; McCall, A.; Lawrence, A.M.; Paloyan, E.
1987-01-01
The question of thyroid neoplasia following high-dose radiation treatment to the neck and mediastinum for malignant neoplasms such as Hodgkin's lymphoma in children and young adults has been raised recently. Five patients, 19 to 39 years old, were operated on for thyroid neoplasms that developed following cervical and mediastinal radiation therapy for Hodgkin's lymphoma. Three patients had papillary carcinomas and two had follicular adenomas. The latency period between radiation exposure and the diagnosis of thyroid neoplasm ranged from eight to 16 years. This limited series provided strong support for the recommendation that children and young adults who are to receive high-dose radiation therapy to the head, neck, and mediastinum should receive suppressive doses of thyroxine prior to radiation therapy in order to suppress thyrotropin (thyroid-stimulating hormone) and then be maintained on a regimen of suppression permanently
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Chondronecrosis of the cricoid cartilage following radiation therapy
International Nuclear Information System (INIS)
Tanabe, Masahiro; Isshiki, Nobuhiko; Kojima, Hisayoshi
1979-01-01
Chondronecrosis of the laryngeal cartilage following radiation therapy is a rare but serious complication. We report herein a case of post-radiation chondronecrosis and discuss factors predisposing to its development. A 67-year-old man received telecobalt therapy for cancer of the right vocal cord. A year after the radiation therapy given in a dose of 7,000r, the patient developed dysphagia and dyspnea. Following tracheotomy, he underwent total laryngectomy. The surgical specimen showed no cancer but chondronecrosis of the cricoid cartilage was present. After laryngectomy he developed progressive soft tissue necrosis of the neck and died following a carotid hemorrhage. (author)
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Radiation therapy quality control in MRCCC radiotherapy units
International Nuclear Information System (INIS)
Fielda Djuita; Rina Taurisia; Andreas Nainggolan
2011-01-01
Increasing cancer patients in Indonesia is not supported with the number of equipment that is able to treat cancer patients, especially in the radiation therapy field. Therefore, several private hospitals have joined to provide radiation therapy services and one of them is MRCCC. As a new hospital providing services in radiotherapy field, the writer tries to present our quality control program that we have done in our hospital. Purpose: As quality control to radiation therapy clinical practice. Methods: Descriptive essay of what we do in our institution. Conclusion: Average output photon and electron lower more than tolerance dose. (author)
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Evolution of radiation therapy: technology of today
International Nuclear Information System (INIS)
Shrivastava, S.K.; Mishra, Shagun
2013-01-01
The three well established arms of treatment are surgery, radiation therapy and chemotherapy. The management of cancer is multidisciplinary; Radiation Oncologists along with Surgical Oncologists and Medical Oncologists are responsible for cancer therapeutics. They all work in close collaboration with Pathologists and Radiologists for cancer diagnosis and staging and rely on Oncology Nurses, Physiotherapists, Occupational Therapists, Nutritionists and Social Workers for optimal treatment and rehabilitation of cancer patients. Therefore cancer management is a team work for getting the best results. Radiation therapy is one of the most effective methods of treating cancer
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Guidelines for radiation therapy in clinical research on bladder cancer
International Nuclear Information System (INIS)
Shipley, W.U.; VanderSchueren, E.; Kitagawa, T.; Gospodarowicz, M.K.; Frommhold, H.; Magno, L.; Mochizuki, S.; VanderBogaert, W.; VanderWerf-Messing, B.
1986-01-01
Bladder cancer is a heterogeneous disease and that there are important tumor characteristics that will predict significant differences in radiation responsiveness. These should in all instances be well documented prospectively in any treatment protocol. However, in this chapter the authors stress a number of factors related to the tumor at presentation as well as the administration of the radiation therapy that can importantly affect the efficacy of the radiation on the patient's tumor, as well as on his or her normal tissues. As Radiation Oncologists, they are most interested in the conducting and reporting of prospective clinical investigations in the use of radiation therapy in the treatment of patients with bladder carcinoma who will be treated with planned preservation of their bladder, but whose radiation therapy may be combined with additional planned bladder-sparing surgery, intraoperative radiation therapy, or chemotherapy
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TH-F-202-03: Advances in MRI for Radiation Therapy
Energy Technology Data Exchange (ETDEWEB)
Cai, J. [Duke University Medical Center (United States)
2016-06-15
MRI has excellent soft tissue contrast and can provide both anatomical and physiological information. It is becoming increasingly important in radiation therapy for treatment planning, image-guided radiation therapy, and treatment assessment. It is critically important at this time point to educate and update our medical physicists about MRI to prepare for the upcoming surge of MRI applications in radiation therapy. This session will review important basics of MR physics, pulse sequence designs, and current radiotherapy application, as well as showcase exciting new developments in MRI that can be potentially useful in radiation therapy. Learning Objectives: To learn basics of MR physics and understand the differences between various pulse sequences To review current applications of MRI in radiation therapy.To discuss recent MRI advances for future MRI guided radiation therapy Partly supported by NIH (1R21CA165384).; W. Miller, Research supported in part by Siemens Healthcare; G. Li, My clinical research is in part supported by NIH U54CA137788. I have a collaborative research project with Philips Healthcare.; J. Cai, jing cai.
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TH-F-202-03: Advances in MRI for Radiation Therapy
International Nuclear Information System (INIS)
Cai, J.
2016-01-01
MRI has excellent soft tissue contrast and can provide both anatomical and physiological information. It is becoming increasingly important in radiation therapy for treatment planning, image-guided radiation therapy, and treatment assessment. It is critically important at this time point to educate and update our medical physicists about MRI to prepare for the upcoming surge of MRI applications in radiation therapy. This session will review important basics of MR physics, pulse sequence designs, and current radiotherapy application, as well as showcase exciting new developments in MRI that can be potentially useful in radiation therapy. Learning Objectives: To learn basics of MR physics and understand the differences between various pulse sequences To review current applications of MRI in radiation therapy.To discuss recent MRI advances for future MRI guided radiation therapy Partly supported by NIH (1R21CA165384).; W. Miller, Research supported in part by Siemens Healthcare; G. Li, My clinical research is in part supported by NIH U54CA137788. I have a collaborative research project with Philips Healthcare.; J. Cai, jing cai
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Radiation therapy in the management of childhood cancer
International Nuclear Information System (INIS)
Kun, L.E.
1987-01-01
Over the past two decades, multimodality treatment regimens have produced significant improvement in survival rates for most types of childhood cancer. The role of radiation therapy has been critically evaluated in prospective clinical trials that established the importance of irradiation in assuring local and regional control of disease central to ultimate survival. Indications for cranial and craniospinal irradiation in acute lymphoblastic leukemia are reviewed, as is difficult technical factors important for successful management. The role of radiation therapy in neuroblastoma and Wilms tumor is reviewed in the context of tumor biology and increasing data from multi-institutional trials. Interactions of irradiation with surgery and chemotherapy are stressed in childhood rhabdomyosarcoma and Ewing sarcoma. Current results in the more common central nervous tumors of childhood are presented, including the central role of radiation therapy in medulloblastoma, astrocytoma, and craniopharyngioma. Concerns regarding late effects of radiation therapy are balanced with the importance of achieving disease control
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Outcome of radiation therapy for patients with Kasabach-Merritt syndrome
International Nuclear Information System (INIS)
Mitsuhashi, Norio; Furuta, Masaya; Sakurai, Hideyuki; Takahashi, Takeo; Kato, Shingo; Nozaki, Miwako; Saito, Yoshihiro; Hayakawa, Kazushige; Niibe, Hideo
1997-01-01
Purpose: The efficacy of radiation therapy for Kasabach-Merritt syndrome, which is characterized by a huge hemangioma with consumption coagulopathy, remains controversial. In this study, we retrospectively investigated the treatment outcome of radiation therapy for seven neonates with Kasabach-Merritt syndrome. Methods and Materials: During the past 25 years we have seen seven children with Kasabach-Merritt syndrome who were treated with radiation therapy. Their ages ranged from 1 day to 5 months, with a median age of 1 month. The hemangioma was located in the extremities in four of seven children. Tumor sizes ranged from 70 cm to more than 150 cm in greatest diameter. Initial platelet counts were all less than 40,000/mm 3 except for one patient. In principle, the total dose applied to the hemangioma was 8-10 Gy, with a daily dose of 1 Gy five times a week. Results: Four of seven hemangiomas responded dramatically, with a concomitant rise of the platelet count to radiation therapy. Although the remaining three hemangiomas, all of which were ill circumscribed by widespread overlying shiny, dusky purple skin, became less tense during radiation therapy. Disseminated intravascular coagulopathy was not improved, but they have responded favorably to two or three courses of radiation therapy with an extended radiation field by 1.5 years of age. As a result, all seven patients are now surviving with no evidence of hemangioma or hematological abnormalities. Shortening of the extremity was observed in three patients who received multiple courses of radiation therapy. Conclusions: Radiation therapy appears to be one of the effective treatment options for Kasabach-Merritt syndrome despite the risk of growth delay and malignancy
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Postoperative radiation therapy for adenoid cystic carcinoma
International Nuclear Information System (INIS)
Oguchi, Masahiko; Shikama, Naoto; Gomi, Koutarou; Shinoda, Atsunori; Nishikawa, Atsushi; Arakawa, Kazukiyo; Sasaki, Shigeru; Takei, Kazuyoshi; Sone, Syusuke
2000-01-01
The authors retrospectively assessed the usefulness of postoperative radiation therapy after local resection of adenoid cystic carcinoma, with emphasis on organ-conserving treatment and the cosmetic results. Between 1985 and 1995, 32 patients underwent local resection followed by postoperative radiation therapy with curative and organ-conserving intent. None of patients received any form of chemotherapy as part of their initial treatment. Radiation therapy was carried out by techniques that were appropriate for the site and extension of each tumor. The 5-year local control, disease-free, and overall survival rates of all patients were 76%, 68%, and 86%, respectively. The 5-year local control rate and disease-free survival rate of patients with microscopically positive margins were 89% and 75%, respectively, and higher than in patients with macroscopically residual disease, but no significant difference in 5-year overall survival rate was observed. The postoperative cosmetic results in 29 patients with head and neck lesions were evaluated. No difference was documented between the cosmetic results postoperatively setting and after postoperative radiotherapy, and no significant differences in cosmetic results were observed according to radiation dose. The combination of local resection with organ-conserving intent and postoperative radiation therapy provided good cosmetic results in patients with T1 or T2 lesions. Postoperative radiation therapy with smaller fractions is useful, because good local control can be achieved in patients with adenoid cystic carcinoma having microscopically positive margins without inducing any late adverse reactions. However, the number of patients was too small and the follow-up period was too short to draw any definite conclusion in regard to fraction size. A much longer follow-up study with a larger number patients will be required to accurately determine the optimal treatment intensity and duration of treatment. (K.H.)
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International Nuclear Information System (INIS)
McDonald, Mark W.; Liu, Yuan; Moore, Michael G.; Johnstone, Peter A. S.
2016-01-01
To evaluate acute toxicity endpoints in a cohort of patients receiving head and neck radiation with proton therapy or intensity modulated radiation therapy (IMRT). Forty patients received comprehensive head and neck radiation including bilateral cervical nodal radiation, given with or without chemotherapy, for tumors of the nasopharynx, nasal cavity or paranasal sinuses, any T stage, N0-2. Fourteen received comprehensive treatment with proton therapy, and 26 were treated with IMRT, either comprehensively or matched to proton therapy delivered to the primary tumor site. Toxicity endpoints assessed included g-tube dependence at the completion of radiation and at 3 months after radiation, opioid pain medication requirement compared to pretreatment normalized as equivalent morphine dose (EMD) at completion of treatment, and at 1 and 3 months after radiation. In a multivariable model including confounding variables of concurrent chemotherapy and involved nodal disease, comprehensive head and neck radiation therapy using proton therapy was associated with a lower opioid pain requirement at the completion of radiation and a lower rate of gastrostomy tube dependence by the completion of radiation therapy and at 3 months after radiation compared to IMRT. Proton therapy was associated with statistically significant lower mean doses to the oral cavity, esophagus, larynx, and parotid glands. In subgroup analysis of 32 patients receiving concurrent chemotherapy, there was a statistically significant correlation with a greater opioid pain medication requirement at the completion of radiation and both increasing mean dose to the oral cavity and to the esophagus. Proton therapy was associated with significantly reduced radiation dose to assessed non-target normal tissues and a reduced rate of gastrostomy tube dependence and opioid pain medication requirements. This warrants further evaluation in larger studies, ideally with patient-reported toxicity outcomes and quality of life
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Directory of Open Access Journals (Sweden)
Abhilash
2016-03-01
Full Text Available INTRODUCTION Breast cancer is the most common cancer in women worldwide and a leading cause of cancer death in females and accounts for 1.8 million new cases and approximately 0.5 million deaths annually. Patients who present with locally advanced breast cancer (LABC require multidisciplinary team approach that incorporates diagnostic imaging, surgery, chemotherapy and histopathological assessment, including molecular-based studies, radiation, and, if indicated, biologic and hormonal therapies. Hypofractionated radiation therapy following mastectomy has been used in many institutions for several decades and have demonstrated equivalent local control, cosmetic and normal tissues between 50 Gy in 25 fractions and various hypofractionated radiotherapy prescriptions employing 13-16 fractions. Evidence suggests that hypofractionated radiotherapy may also be safe and effective for regional nodal disease. AIMS AND OBJECTIVES To compare the local control and side effects of hypofractionated radiation therapy with conventional radiation therapy in post mastectomy carcinoma breast with stage II and III and to compare the tolerability and compliance of both schedules. MATERIALS AND METHODS The study was conducted on 60 histopathologically proven patients of carcinoma of breast, treated surgically with modified radical mastectomy. Group I patients were given external radiation to chest flap and drainage areas, a dose of 39 Gy/13 fractions/3.1 weeks, a daily dose 3 Gy for 13 fractions in 4 days a week schedule and Group II patients were given external radiation to chest flap and drainage areas, a dose of 50 Gy/25 fractions/5 weeks, to receive a daily dose 2 Gy for 25 fractions in a 5 days a week schedule. RESULTS The median age at presentation in Group I and II was 48 and 50 years respectively. Locoregional control after completion of radiotherapy in Group I vs. Group II was 26/30 (86.7% vs. 27/30 (90% respectively. Acute reactions and their grades in Group
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21 CFR 892.5750 - Radionuclide radiation therapy system.
2010-04-01
... system. (a) Identification. A radionuclide radiation therapy system is a device intended to permit an... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide radiation therapy system. 892.5750... patient's body. This generic type of device may include signal analysis and display equipment, patient and...
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DOE Research Contributions to Radiation and Cancer Therapy
dropdown arrow Site Map A-Z Index Menu Synopsis DOE Research Contributions to Radiation and Cancer Therapy Possible: DOE Advanced Biomedical Technology Research, page 10 Over the time span of many years, DOE's research has made many contributions to radiation and cancer therapy, including PEREGRINE and Boron Neutron
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Radiation therapy for chordomas
International Nuclear Information System (INIS)
Ikeda, Hajime; Takahashi, Takeo; Nakamura, Yuji; Niibe, Hideo
1995-01-01
Chordomas are slow-growing primary malignant bone tumors which originate from remnants of the fetal notochordal system. They are difficult to control by surgery alone. Four patients with chordomas treated with radiation therapy were studied, and the effectiveness of radiotherapy was evaluated. These 4 (3.8%) patients were among 106 patients with primary malignant bone tumors referred to us from 1959 to 1987. Primary sites were the sacrococcygeal region in three patients and the clivus in one. The patients' ages ranged from 51 to 75 years. The male : female ratio was 1 : 1. Patients received 48 to 60 Gy of radiation to the primary sites. Because the radiosensitivity of the tumors was low, the responses were poor. The duration of survival was 6, 33, 68, and 125 months. The cause of death in each case was local recurrence of tumor. As a result, a dose greater than 60 Gy is thought to be necessary for curative radiotherapy. Proton beam therapy seems to be best choice for chordomas in the clivus, and mixed-beam (proton and megavolt age X-ray) therapy or multiportal irradiation, which gives an ideal spatial dose distribution, seems to be most suitable for sacrococcygeal chordomas. (author)
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Cone-Beam Computed Tomographic Image Guidance for Lung Cancer Radiation Therapy
International Nuclear Information System (INIS)
Bissonnette, Jean-Pierre; Purdie, Thomas G.; Higgins, Jane A.; Li, Winnie; Bezjak, Andrea
2009-01-01
Purpose: To determine the geometric accuracy of lung cancer radiotherapy using daily volumetric, cone-beam CT (CBCT) image guidance and online couch position adjustment. Methods and Materials: Initial setup accuracy using localization CBCT was analyzed in three lung cancer patient cohorts. The first (n = 19) involved patients with early-stage non-small-cell lung cancer (NSCLC) treated using stereotactic body radiotherapy (SBRT). The second (n = 48) and third groups (n = 20) involved patients with locally advanced NSCLC adjusted with manual and remote-controlled couch adjustment, respectively. For each group, the couch position was adjusted when positional discrepancies exceeded ±3 mm in any direction, with the remote-controlled couch correcting all three directions simultaneously. Adjustment accuracy was verified with a second CBCT. Population-based setup margins were derived from systematic (Σ) and random (σ) positional errors for each group. Results: Localization imaging demonstrates that 3D positioning errors exceeding 5 mm occur in 54.5% of all delivered fractions. CBCT reduces these errors; post-correction Σ and σ ranged from 1.2 to 1.9 mm for Group 1, with 82% of all fractions within ±3 mm. For Group 2, Σ and σ ranged between 0.8 and 1.8 mm, with 76% of all treatment fractions within ±3 mm. For Group 3, the remote-controlled couch raised this to 84%, and Σ and σ were reduced to 0.4 to 1.7 mm. For each group, the postcorrection setup margins were 4 to 6 mm, 3 to 4 mm, and 2 to 3 mm, respectively. Conclusions: Using IGRT, high geometric accuracy is achievable for NSCLC patients, potentially leading to reduced PTV margins, improved outcomes and empowering adaptive radiation therapy for lung cancer
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Radiation Therapy and Hearing Loss
International Nuclear Information System (INIS)
Bhandare, Niranjan; Jackson, Andrew; Eisbruch, Avraham; Pan, Charlie C.; Flickinger, John C.; Antonelli, Patrick; Mendenhall, William M.
2010-01-01
A review of literature on the development of sensorineural hearing loss after high-dose radiation therapy for head-and-neck tumors and stereotactic radiosurgery or fractionated stereotactic radiotherapy for the treatment of vestibular schwannoma is presented. Because of the small volume of the cochlea a dose-volume analysis is not feasible. Instead, the current literature on the effect of the mean dose received by the cochlea and other treatment- and patient-related factors on outcome are evaluated. Based on the data, a specific threshold dose to cochlea for sensorineural hearing loss cannot be determined; therefore, dose-prescription limits are suggested. A standard for evaluating radiation therapy-associated ototoxicity as well as a detailed approach for scoring toxicity is presented.
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The physical basis and future of radiation therapy.
Bortfeld, T; Jeraj, R
2011-06-01
The remarkable progress in radiation therapy over the last century has been largely due to our ability to more effectively focus and deliver radiation to the tumour target volume. Physics discoveries and technology inventions have been an important driving force behind this progress. However, there is still plenty of room left for future improvements through physics, for example image guidance and four-dimensional motion management and particle therapy, as well as increased efficiency of more compact and cheaper technologies. Bigger challenges lie ahead of physicists in radiation therapy beyond the dose localisation problem, for example in the areas of biological target definition, improved modelling for normal tissues and tumours, advanced multicriteria and robust optimisation, and continuous incorporation of advanced technologies such as molecular imaging. The success of physics in radiation therapy has been based on the continued "fuelling" of the field with new discoveries and inventions from physics research. A key to the success has been the application of the rigorous scientific method. In spite of the importance of physics research for radiation therapy, too few physicists are currently involved in cutting-edge research. The increased emphasis on more "professionalism" in medical physics will tip the situation even more off balance. To prevent this from happening, we argue that medical physics needs more research positions, and more and better academic programmes. Only with more emphasis on medical physics research will the future of radiation therapy and other physics-related medical specialties look as bright as the past, and medical physics will maintain a status as one of the most exciting fields of applied physics.
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The physical basis and future of radiation therapy
Bortfeld, T; Jeraj, R
2011-01-01
The remarkable progress in radiation therapy over the last century has been largely due to our ability to more effectively focus and deliver radiation to the tumour target volume. Physics discoveries and technology inventions have been an important driving force behind this progress. However, there is still plenty of room left for future improvements through physics, for example image guidance and four-dimensional motion management and particle therapy, as well as increased efficiency of more compact and cheaper technologies. Bigger challenges lie ahead of physicists in radiation therapy beyond the dose localisation problem, for example in the areas of biological target definition, improved modelling for normal tissues and tumours, advanced multicriteria and robust optimisation, and continuous incorporation of advanced technologies such as molecular imaging. The success of physics in radiation therapy has been based on the continued “fuelling” of the field with new discoveries and inventions from physics research. A key to the success has been the application of the rigorous scientific method. In spite of the importance of physics research for radiation therapy, too few physicists are currently involved in cutting-edge research. The increased emphasis on more “professionalism” in medical physics will tip the situation even more off balance. To prevent this from happening, we argue that medical physics needs more research positions, and more and better academic programmes. Only with more emphasis on medical physics research will the future of radiation therapy and other physics-related medical specialties look as bright as the past, and medical physics will maintain a status as one of the most exciting fields of applied physics. PMID:21606068
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Results of radiation therapy in periarthritis humeroscapularis
International Nuclear Information System (INIS)
Schultze, J.; Schlichting, G.; Galalae, R.; Kimmig, B.; Koltze, H.
2004-01-01
Background: radiation therapy is applied in painful degenerative shoulder diseases. Aim of this work was to evaluate the contribution of radiation therapy to symptomatic improvement in periarthritis humeroscapularis. Methods: ninety-four patients with periarthritis humeroscapularis were treated in two institutions. Mean age was 68 years, sex distribution were 32 men and 62 women. In 58 cases the right side was affected, left in 36 cases. At single doses of 0,75 Gy once a week a total dose of 6 Gy was applied The treatment effect was evaluated by the standardized von Pannewitz-score at the end of the treatment up to 6 months thereafter. Results: the treatment results of all the 94 patients were documentated at the end of therapy. Seventy-one patients were followed at least for further 4 months. Radiogenic side-effects were not noticed. The symptoms of 54 patients (57.4%) were improved or vanished, in 40 cases the symptoms were not significantly affected (42.6%). Four months after therapy 42 of 71 patients were improved (59.2%), 29 unchanged (40.8%). The treatment effect occured typically up to 2 months after therapy, there were no age-related differences. Also in recurrent radiation therapies the symptoms improved, in 80 percent after one preceding therapy, however only in 31.2 percent after multiple prior radiotherapies. (orig.)
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Two case reports of a cerebrovascular disorder after radiation therapy
International Nuclear Information System (INIS)
Ono, Jiro; Mimaki, Takashi; Tagawa, Tetsuzo
1985-01-01
The use of radiation therapy has significantly improved the prognosis of certain brain tumors. However, a few patients have been reported who developed cerebrovasculopathy accompanying transient ischemic attacks several months to several years after radiation therapy. The present report described cerebrovascular disorders after radiation therapy for brain tumors. The first case was an 8-year-6-month-old boy treated with a total dose of 5,200 rads after partial removal of a right periventricular astrocytoma extending into the thalamus. Two years and 7 months after completion of the radiation therapy, he showed transient ischemic attacks of numbness in the right upper limb and right hemiparesis. Arteriography revealed stenosis or occlusion of the anterior and middle cerebral arteries. Preoperative arteriography did not show occlusion nor narrowing of the cerebral arteries. The second case was a 2-year-8-month-old boy diagnosed as diencephalic syndrome, because of marked emaciation and a huge tumor mass expanding into the diencephalon and frontal lobe on the brain CT scan. He was irradiated with up to 5,000 rads. Seven months after radiation therapy, he developed transient right hemiparesis. Arteriography revealed stenosis or occlusion of the middle sized cerebral arteries. Although radiation therapy is acceptable in children with certain brain tumors, and very few patients develop postradiation vasculopathy, the risk of radiation therapy requires more careful consideration in the treatment of intracranial tumors. (author)
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Monte Carlo techniques in radiation therapy
Verhaegen, Frank
2013-01-01
Modern cancer treatment relies on Monte Carlo simulations to help radiotherapists and clinical physicists better understand and compute radiation dose from imaging devices as well as exploit four-dimensional imaging data. With Monte Carlo-based treatment planning tools now available from commercial vendors, a complete transition to Monte Carlo-based dose calculation methods in radiotherapy could likely take place in the next decade. Monte Carlo Techniques in Radiation Therapy explores the use of Monte Carlo methods for modeling various features of internal and external radiation sources, including light ion beams. The book-the first of its kind-addresses applications of the Monte Carlo particle transport simulation technique in radiation therapy, mainly focusing on external beam radiotherapy and brachytherapy. It presents the mathematical and technical aspects of the methods in particle transport simulations. The book also discusses the modeling of medical linacs and other irradiation devices; issues specific...
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A case showing a blistering disorder in radiation dermatitis during radiation therapy
International Nuclear Information System (INIS)
Nonoshita, Takeshi; Nakamura, Katsumasa; Shioyama, Yoshiyuki
2007-01-01
We experienced a case showing a blistering disorder in radiation dermatitis during radiation therapy for thymic cancer. Application of steroid to the lesion improved blisters. The literature on bullous eruption including radiation-induced bullous pemhigoid was critically reviewed. (author)
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Radiation therapy for pleural mesothelioma
International Nuclear Information System (INIS)
Seydel, H.G.
1986-01-01
There is clear evidence that both pleural and peritoneal malignant mesothelioma are increasing in incidence in the United States. There is a recognized long period of latency from asbestos exposure to the emergence and diagnosis of tumor. Considering the levels of asbestos utilization in the mid-20th century, we must expect that the number of cases will continue to increase until the end of this century. Evaluation of treatment options is thus a critical issue in determining treatment approaches for this disease. Recognized only recently, mesothelioma has no effective treatment, and patients are reported only anecdotally as cured. Pleural mesothelioma is the more common presentation, but even here the reports are from small, uncontrolled series. Only one study is available in which a concomitant comparison of treatment methods was carried out. Randomized clinical studies regarding treatment of pleural mesothelioma have only recently been initiated by the clinical cooperative groups. There is thus a paucity of information on treatment in general and radiation therapy specifically for malignant mesothelioma. This chapter reviews the reported experience using radiation therapy alone and combined with other modalities for the treatment of malignant pleural mesothelioma and considers the potential for improvement of the results of current methods of radiation therapy
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International Nuclear Information System (INIS)
Song, William Y.; Schaly, Bryan; Bauman, Glenn; Battista, Jerry J.; Van Dyk, Jake
2006-01-01
Purpose: To quantify the mitigation of geometric uncertainties achieved with the application of various patient setup techniques during the delivery of hypofractionated prostate cancer treatments, using tumor control probability (TCP) and normal tissue complication probability. Methods and Materials: Five prostate cancer patients with ∼16 treatment CT studies, taken during the course of their radiation therapy (77 total), were analyzed. All patients were planned twice with an 18 MV six-field conformal technique, with 10- and 5-mm margin sizes, with various hypofractionation schedules (5 to 35 fractions). Subsequently, four clinically relevant patient setup techniques (laser guided and image guided) were simulated to deliver such schedules. Results: As hypothesized, the impact of geometric uncertainties on clinical outcomes increased with more hypofractionated schedules. However, the absolute gain in TCP due to hypofractionation (up to 21.8% increase) was significantly higher compared with the losses due to geometric uncertainties (up to 8.6% decrease). Conclusions: The results of this study suggest that, although the impact of geometric uncertainties on the treatment outcomes increases as the number of fractions decrease, the reduction in TCP due to the uncertainties does not significantly offset the expected theoretical gain in TCP by hypofractionation
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van de Schoot, A.J.A.J.
2016-01-01
In cervical cancer radiation therapy, an adaptive strategy is required to compensate for interfraction anatomical variations in order to achieve adequate dose delivery. In this thesis, we have aimed at optimizing adaptive radiation therapy in cervical cancer to improve treatment efficiency and
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Oral care of the cancer patient receiving radiation therapy
Energy Technology Data Exchange (ETDEWEB)
Holtzhausen, T [Medical Univ. of Southern Africa, Pretoria (South Africa). Dept. of Community Dentistry
1982-07-01
Radiation therapy is frequently being used for the patient with oral cancer. The survival rate is increasing, due to more effective treatment technique. The question of whether any teeth should be extracted, the mode of therapy and the side effects of radiation like Xerostomia, caries, stomatitis, trismus and osteo-radionecrosis and also post radiation care are discussed.
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Radiation therapy: age-related macular degeneration.
Mendez, Carlos A Medina; Ehlers, Justis P
2013-01-01
Age-related macular degeneration (AMD) is the leading cause of severe irreversible vision loss in patients over the age of 50 years in the developed world. Neovascular AMD (NVAMD) is responsible for 90% of the cases with severe visual loss. In the last decade, the treatment paradigm for NVAMD has been transformed by the advent of anti-vascular endothelial growth factor therapy. Despite the excellent results of anti-vascular endothelial growth factor therapy, frequent injections remain a necessity for most patients. The burden of these frequent visits as well as the cumulative risks of indefinite intravitreal injections demand continued pursuit of more enduring therapy that provides similar functional results. Radiotherapy has been studied for two decades as a potential therapy for NVAMD. Because of its antiangiogenic properties, radiation therapy remains a promising potential adjunctive resource for the treatment of choroidal neovascularization secondary to NVAMD. This review considers the past, present and future of radiation as a treatment or combination treatment of NVAMD. Copyright © 2013 S. Karger AG, Basel.
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Computed tomography in radiation therapy planning: Thoracic region
International Nuclear Information System (INIS)
Seydel, H.G.; Zingas, A.; Haghbin, M.; Mondalek, P.; Smereka, R.
1983-01-01
With the explosive spread of computed tomographic (CT) scanning throughout the United States, one of the main applications has been in patients who are treated for cancer by surgery, radiation therapy, or chemotherapy. For the radiation oncologist, the desire to provide local tumor control and avoid geographic misses to achieve an expected prolongation of survival has led to the use of large radiation fields in the treatment of intrathoracic cancer, including bronchogenic carcinoma, cancer of the esophagus, and other malignant tumors. The optimal radiation therapy plan is a balance between local tumor control and the necessity to preserve normal structures by the use of directed and limited fields for bulk disease. CT scanning has been employed to accurately demonstrate the extent of tumor as well as to determine the isodose distribution of radiation, including the spatial distribution of radiation portals in single planar and three-dimensional aspects as well as consideration of tissue inhomogeneities. The accurate planning of the distribution of therapeutic irradiation includes both the tumor-bearing target volume and the critical normal tissues. This chapter provides information regarding these aspects of the application of CT scanning to radiation therapy for bronchogenic carcinoma and carcinoma of the esophagus
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Radiation optic neuropathy after external beam radiation therapy for acromegaly: report of two cases
International Nuclear Information System (INIS)
Bergh, Alfons C.M. van den; Hoving, Marjanke A.; Links, Thera P.; Dullaart, Robin P.F.; Ranchor, Adelita V.; Weeme, Cees A. ter; Canrinus, Alof A.; Szabo, Ben G.; Pott, Jan-Willem R.
2003-01-01
For diagnosing radiation optic neuropathy (RON) ophthalmological and imaging data were evaluated from 63 acromegalic patients, irradiated between 1967 and 1998. Two patients developed RON: one patient in one optic nerve 10 years and another patient in both optic nerves 5 months after radiation therapy. RON is a rare complication after external beam radiation therapy for acromegaly, which can occur after a considerable latency period
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Modeling Internal Radiation Therapy
van den Broek, Egon; Schouten, Theo E.; Pellegrini, M.; Fred, A.; Filipe, J.; Gamboa, H.
2011-01-01
A new technique is described to model (internal) radiation therapy. It is founded on morphological processing, in particular distance transforms. Its formal basis is presented as well as its implementation via the Fast Exact Euclidean Distance (FEED) transform. Its use for all variations of internal
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SU-E-T-463: Quantification of Rotational Variation in Mouse Setup for IGRT
Energy Technology Data Exchange (ETDEWEB)
McCarroll, R; Rubinstein, A; Kingsley, C; Yang, J; Yang, P; Court, L [UT MD Anderson Cancer Center, Houston, TX (United States)
2014-06-01
Purpose: New small-animal irradiators include extremely precise IGRT capabilities. However, mouse immobilization and localization remains a challenge. In particular, unlike week-to-week translational displacements, rotational changes in positioning are not easily corrected for in subject setup. Using two methods of setup, we aim to quantify week-to-week rotational variation in mice for the purpose of IGRT planning in small animal studies. Methods: Ten mice were imaged weekly using breath-hold CBCT (X-RAD 225 Cx), with the mouse positioned in a half-pipe support, providing 40 scans. A second group of two mice were positioned in a 3D printed immobilization device, which was created using a CT from a similarly shaped mouse, providing 10 scans. For each mouse, the first image was taken to be the reference image. Subsequent CT images were then rigidly registered, based on bony anatomy. Rotations in the axial (roll), sagittal (pitch), and coronal (yaw) planes were recorded and used to quantify variation in angular setup. Results: For the mice imaged in the half pipe, average magnitude of roll was found to be 5.4±4.6° (range: −12.9:18.86°), of pitch 1.6±1.3° (range: −1.4:4.7°), and of yaw 1.9±1.5° (range −5.4:1.1°). For the mice imaged in the printed setup; average magnitude of roll was found to be 0.64±0.6° (range: −2.1:1.0°), of pitch 0.6±0.4° (range: 0.0:1.3°), and of yaw 0.2±0.1° (range: 0.0:0.4°). The printed setup provided reduction in roll, pitch, and yaw by 88, 62, and 90 percent, respectively. Conclusion: For the typical setup routine, roll in mouse position is the dominant source of rotational variation. However, when a printed device was used, drastic improvements in mouse immobilization were seen. This work provides a promising foundation for mouse immobilization, required for full scale small animal IGRT. Currently, we are making improvements to allo±w the use of a similar system for MR, PET, and bioluminescence.
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Radiation Therapy of Suprasellar Germ Cell Tumors
International Nuclear Information System (INIS)
Park, Woo Yoon; Choi, Doo Ho; Choi, Eun Kyung; Kim, Il Han; Ha, Sung Whan; Park, Charn Il
1988-01-01
A retrospective study was performed on 15 patients with suprasellar germ cell tumors treated by megavoltage external beam irradiation between Feb. 1979 and Dec. 1985. Follow-up period of survivors was 30 to 91 months. Histologic diagnosis was obtained before radiation therapy in 10 patients (9 germinomas and 1 mixed). Five patients were treated without histologic verification. In 9 patients with biopsy-proven germinomas radiation therapy was delivered to the craniospinal axis in 6, to the whole brain in 3. In 5 patients with mixed germ cell tumor or elevated tumor marker, irradiation was delivered to the craniospinal axis in 2, to the whole brain in 2, and to the primary site only in 1. Total doses ranged from 5,000 to 5,500 cGy to the primary site, 3,000 to 4,400 cGy to the whole brain, and 1,300 to 3,000 cGy to the spine. In these 14, local tumor was controlled and primary or spinal failure was not observed. One patient without elevated tumor marker was treated to the whole brain, The tumor was not controlled and he had spinal recurrence. It is proven that radiation therapy is an effective treatment for suprasellar germ cell tumors. The neuroendocrinologic presentation, tumor marker status, early response to radiation measured on CT seem to be useful means for selecting patients for radiation therapy when tissue diagnosis is not available
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Radiation Therapy for Neovascular Age-related Macular Degeneration
Energy Technology Data Exchange (ETDEWEB)
Kishan, Amar U. [Harvard Medical School, Boston, Massachusetts (United States); Modjtahedi, Bobeck S.; Morse, Lawrence S. [Department of Ophthalmology and Vision Sciences, University of California, Davis, Sacramento, California (United States); Lee, Percy, E-mail: percylee@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, California (United States)
2013-03-01
In the enormity of the public health burden imposed by age-related macular degeneration (ARMD), much effort has been directed toward identifying effective and efficient treatments. Currently, anti-vascular endothelial growth factor (VEGF) injections have demonstrated considerably efficacy in treating neovascular ARMD, but patients require frequent treatment to fully benefit. Here, we review the rationale and evidence for radiation therapy of ARMD. The results of early photon external beam radiation therapy are included to provide a framework for the sequential discussion of evidence for the usage of stereotactic radiation therapy, proton therapy, and brachytherapy. The evidence suggests that these 3 modern modalities can provide a dose-dependent benefit in the treatment of ARMD. Most importantly, preliminary data suggest that all 3 can be used in conjunction with anti-VEGF therapeutics, thereby reducing the frequency of anti-VEGF injections required to maintain visual acuity.
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Radiation Therapy of Pituitary Tumors
Energy Technology Data Exchange (ETDEWEB)
Park, Moon Baik; Hong, Seong Eong [Kyunghee University College of Medicine, Seoul (Korea, Republic of)
1989-12-15
Radiation treatment results were analyzed in a retrospective analysis of 47 patients with pituitary adenoma treated with radiation alone or combined with surgery from 1974 through 1987 at the Department of Therapeutic Radiology of Kyung Hee University. The 5-year overall survival rates for all patients was 80.4%. Radiation therapy was effective for improving visual symptoms and headache, but could not normalize amenorrhea and galactorrhoea. There was no difference of survival rate between radiation alone and combination with surgery. Prognostic factors such as age, sex, disease type, visual field, headache and surgical treatment were statistically no significant in survival rates of these patients.
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Radiation Therapy of Pituitary Tumors
International Nuclear Information System (INIS)
Park, Moon Baik; Hong, Seong Eong
1989-01-01
Radiation treatment results were analyzed in a retrospective analysis of 47 patients with pituitary adenoma treated with radiation alone or combined with surgery from 1974 through 1987 at the Department of Therapeutic Radiology of Kyung Hee University. The 5-year overall survival rates for all patients was 80.4%. Radiation therapy was effective for improving visual symptoms and headache, but could not normalize amenorrhea and galactorrhoea. There was no difference of survival rate between radiation alone and combination with surgery. Prognostic factors such as age, sex, disease type, visual field, headache and surgical treatment were statistically no significant in survival rates of these patients
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Radiation therapy of brain metastases
Energy Technology Data Exchange (ETDEWEB)
Sauer, R; Huenig, R [Kantonsspital Basel (Switzerland). Universitaetsinstitut fuer Medizinische Radiologie
1975-08-01
Experiences are reported obtained with radiation therapy of brain metastases in 121 patients during the last 15 years. The treatment to a lesser extent aimed at prolongation of survival but much more at the attempt to alleviate troubles and to spare pain. The indication thus involved medical points of view as well as ethical ones. The radiotherapy of cerebral metastases comprises the whole cranial volume and requires a focal dose of minimally 4,000 R within four weeks. In 53% of the patients, the regression of neurological symptoms was considerable, in 18% even complete, partly beginning already after a few days of treatment. The number of recurrences was small. Under conditions of rigorous indication, the radiation therapy of brain metastases offers a rewarding palliative measure.
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Some computer graphical user interfaces in radiation therapy.
Chow, James C L
2016-03-28
In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls
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Drug delivery system and radiation therapy
International Nuclear Information System (INIS)
Shibata, Tokushi
2005-01-01
This paper describes the review of radiation therapy, neutron capture therapy (NCT) and drug delivery system for the latter. In cancer radiation therapy, there are problems of body movement like breathing, needless irradiation of normal tissues, difficulty to decide the correct irradiation position and tumor morphology. NCT has advantages to overcome these, and since boron has a big cross section for thermal neutron, NPT uses the reaction 10 B(n, α) 7 Li in the target cancer which previously incorporated the boron-containing drug. During the period 1966-1996, 246 patients were treated with this in Japan and the treatment has been continued thereafter. The tasks for NCT are developments of drug delivery system efficient to deliver the drug into the tumor and of convenient neutron source like the accelerator. (S.I.)
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Computer models for optimizing radiation therapy
International Nuclear Information System (INIS)
Duechting, W.
1998-01-01
The aim of this contribution is to outline how methods of system analysis, control therapy and modelling can be applied to simulate normal and malignant cell growth and to optimize cancer treatment as for instance radiation therapy. Based on biological observations and cell kinetic data, several types of models have been developed describing the growth of tumor spheroids and the cell renewal of normal tissue. The irradiation model is represented by the so-called linear-quadratic model describing the survival fraction as a function of the dose. Based thereon, numerous simulation runs for different treatment schemes can be performed. Thus, it is possible to study the radiation effect on tumor and normal tissue separately. Finally, this method enables a computer-assisted recommendation for an optimal patient-specific treatment schedule prior to clinical therapy. (orig.) [de
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Radiation therapy of Graves' ophthalmopathy
Energy Technology Data Exchange (ETDEWEB)
Kawamura, Toshiki; Koga, Sukehiko; Anno, Hirofumi; Komai, Satoshi (Fujita-Gakuen Health Univ., Toyoake, Aichi (Japan))
1992-01-01
During the decade from 1978 to 1987, 20 patients with Graves' ophthalmopathy were treated with irradiation of 2000 cGy to the orbital tissue. We examined the effects of the therapy on 17 such patients. Exophthalmos tended to decrease. When the degree of deviation of the exophthalmic eye was small, the effect of therapy tended to be better than when it was large. Two cases that showed an increase in retrobulbar fatty tissue without thickening of the extraocular muscles did not respond as well as those that had thickening of the extraocular muscles. Diplopia tended to improve both subjectively and objectively. Ocular movement improved in 11 of the 17 patients. There were no serious radiation injuries after the radiation therapy, except for some transient swelling of the eyelid. (author).
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Radiation Therapy in Elderly Skin Cancer
Energy Technology Data Exchange (ETDEWEB)
Kim, Jin Hee [Keimyung University College of Medicine, Daegu (Korea, Republic of)
2008-06-15
To evaluate the long term results (local control, survival, failure, and complications) after radiation therapy for skin cancer in elderly patients. The study spanned from January 1990 to October 2002. Fifteen elderly patients with skin cancer were treated by radiotherapy at the Keimyung University Dongsan Medical Center. The age distribution of the patients surveyed was 72 to 95 years, with a median age of 78.8 years. The pathologic classification of the 15 patients included squamous cell carcinoma (10 patients), basal cell carcinoma (3 patients), verrucous carcinoma (1 patient) and skin adnexal origin carcinoma (1 patient). The most common tumor location was the head (13 patients). The mean tumor diameter was 4.9 cm (range 2 to 9 cm). The radiation dose was delivered via an electron beam of 6 to 15 MeV. The dose range was adjusted to the tumor diameter and depth of tumor invasion. The total radiation dose ranged from 50{approx}80 Gy (mean: 66 Gy) with a 2 Gy fractional dose prescribed to the 80% isodose line once a day and 5 times a week. One patient with lymph node metastasis was treated with six MV photon beams boosted with electron beams. The length of the follow-up periods ranged from 10 to 120 months with a median follow-up period of 48 months. The local control rates were 100% (15/15). In addition, the five year disease free survival rate (5YDFS) was 80% and twelve patients (80%) had no recurrence and skin cancer recurrence occurred in 3 patients (20%). Three patients have lived an average of 90 months (68{approx}120 months) without recurrence or metastasis. A total of 9 patients who died as a result of other causes had a mean survival time of 55.8 months after radiation therapy. No severe acute or chronic complications were observed after radiation therapy. Only minor complications including radiation dermatitis was treated with supportive care. The results suggest that radiation therapy is an effective and safe treatment method for the treatment of skin
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Accompanying therapy with melatonin at radiation therapy for uterine body cancer
International Nuclear Information System (INIS)
Prokhach, N.E.; Sorochan, P.P.; Gromakova, Yi.A.; Krugova, M.; Sukhyin, V.S.
2011-01-01
The results of treatment for uterine body cancer using post-operative radiation therapy (RT) accompanied by melatonin administration are analyzed. Accompanying therapy with melatonin limited negative RT influence on hematological and immune indices and prevented aggravation of quality of life.
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Radiation Induced Rib Fractures on Bone Scan after Breast Cancer Surgery and Radiation Therapy
International Nuclear Information System (INIS)
Kim, Hae Won; Won, Kyoung Sook; Zeon, Seok Kil; Kim, Jin Hee
2009-01-01
This study is to evaluate rib fractures on bone scan in breast cancer patients treated with breast cancer surgery and radiation therapy and to evaluate its relation with radiation therapy and operation modality. Two hundred seventy cases that underwent serial bone scan after breast cancer surgery and radiation therapy were enrolled. Bone scan and chest CT findings of rib fracture were analyzed. The rib uptake was seen in 74 of 270 cases (27.4%) on bone scan and 50 cases (18.5%) were confirmed to have rib fracture by chest CT. The rate of modified radical mastectomy in patients with rib fracture was significantly higher than that in patients without rib fracture (66.0% vs. 27.0%, p=0.000). The rate of additional radiation therapy to axillar or supraclavicular regions in patients with rib fracture was significantly higher than that in patients without rib fracture (62.0% vs. 28.6%, p=0.000). Rib fracture was seen most frequently at 1-2 years after radiation therapy (51.9%) and single rib fracture was seen most frequently (55.2%). Of total 106 rib fractures, focal rib uptake was seen in 94 ribs (88.7%) and diffuse rib uptake was seen in 12 ribs (11.3%). On one year follow-up bone scan, complete resolution of rib uptake was seen in 15 ribs (14.2%). On chest CT, the rate of fracture line in ribs with intense uptake was significantly higher than that in ribs with mild or moderate uptake (p=0.000). The rate of presence of fracture line in ribs with focal uptake was significantly higher than that in ribs with diffuse uptake (p=0.001). Rib fracture in breast cancer patients after radiation therapy was related to radiation portal and operation modality. It should be interpreted carefully as a differential diagnosis of bone metastasis
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Radiation Induced Rib Fractures on Bone Scan after Breast Cancer Surgery and Radiation Therapy
Energy Technology Data Exchange (ETDEWEB)
Kim, Hae Won; Won, Kyoung Sook; Zeon, Seok Kil; Kim, Jin Hee [Keimyung University, School of Medicine, Daegu (Korea, Republic of)
2009-08-15
This study is to evaluate rib fractures on bone scan in breast cancer patients treated with breast cancer surgery and radiation therapy and to evaluate its relation with radiation therapy and operation modality. Two hundred seventy cases that underwent serial bone scan after breast cancer surgery and radiation therapy were enrolled. Bone scan and chest CT findings of rib fracture were analyzed. The rib uptake was seen in 74 of 270 cases (27.4%) on bone scan and 50 cases (18.5%) were confirmed to have rib fracture by chest CT. The rate of modified radical mastectomy in patients with rib fracture was significantly higher than that in patients without rib fracture (66.0% vs. 27.0%, p=0.000). The rate of additional radiation therapy to axillar or supraclavicular regions in patients with rib fracture was significantly higher than that in patients without rib fracture (62.0% vs. 28.6%, p=0.000). Rib fracture was seen most frequently at 1-2 years after radiation therapy (51.9%) and single rib fracture was seen most frequently (55.2%). Of total 106 rib fractures, focal rib uptake was seen in 94 ribs (88.7%) and diffuse rib uptake was seen in 12 ribs (11.3%). On one year follow-up bone scan, complete resolution of rib uptake was seen in 15 ribs (14.2%). On chest CT, the rate of fracture line in ribs with intense uptake was significantly higher than that in ribs with mild or moderate uptake (p=0.000). The rate of presence of fracture line in ribs with focal uptake was significantly higher than that in ribs with diffuse uptake (p=0.001). Rib fracture in breast cancer patients after radiation therapy was related to radiation portal and operation modality. It should be interpreted carefully as a differential diagnosis of bone metastasis.
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IMRT, IGRT, SBRT - Advances in the Treatment Planning and Delivery of Radiotherapy
Meyer, JL
2011-01-01
Over the last 4 years, IMRT, IGRT, SBRT: Advances in the Treatment Planning and Delivery of Radiotherapy has become a standard reference in the field. During this time, however, significant progress in high-precision technologies for the planning and delivery of radiotherapy in cancer treatment has called for a second edition to include these new developments. Thoroughly updated and extended, this new edition offers a comprehensive guide and overview of these new technologies and the many clinical treatment programs that bring them into practical use. Advances in intensity-modulated radiothera
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Spontaneous pneumothorax after upper mantle radiation therapy for Hodgkin disease
International Nuclear Information System (INIS)
Paszat, L.; Basrur, V.; Tadros, A.
1986-01-01
Between 1967 and 1981, 158 of 256 consecutive adult patients received upper mantle (UM) radiation therapy as part of initial treatment of Hodgkin disease at the Hamilton Regional Cancer Centre. Chemotherapy was also part of the initial treatment in 21 of 158 patients who received UM radiation therapy. Spontaneous pneumothorax was observed in six of 158 patients during remission after UM radiation therapy in this series. Three cases were incidental findings on follow-up radiographs, but three other patients were seen initially with symptoms of spontaneous pneumothorax. The entity occurred in three of 21 patients (14%) treated with UM radiation therapy and chemotherapy, and in three of 137 (2%) treated with UM radiation therapy (P < .05). Within the range of UM doses (3,500-4,000 cGy in 4 weeks), higher dose was not associated with higher risk of spontaneous pneumothorax. Although these cases of spontaneous pneumothorax are clustered in an age range classic for this entity, the incidence of spontaneous pneumothorax in this group of patients is higher than the anticipated lifetime incidence of 1:500 for the general population. This risk of spontaneous pneumothorax after UM radiation therapy may be even higher in patients who also receive chemotherapy
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Palliative radiation therapy for overloading radiotherapy centre, especially for developing country
International Nuclear Information System (INIS)
Myo, M.; Susworo; San, T.
2001-01-01
In a developing country, most of the cancer cases are diagnosed in the advanced stages. So, the palliative radiation therapy is the only choice of therapy for these inoperable cases where chemotherapy is not effective or affordable. In conventional radiation therapy, a daily dose of 200 cGy for total 4000 cGy in more than 20 fractions (sometimes, up to 6000 cGy) is used. By using linear-quadratic model theory of cell killing by radiation, it can be calculated early and late effects by using alpha and beta ratio. This theory is still the best for radiation cell killing until the new detail one is discovered. These data are obtained by experimental as well as clinical results. The effective radiation dose can be calculated by using the data to different organs which is involved in the radiation fields. This can change the daily dose to palliative cases in which the late effect is unnecessary. The daily doses can be 300, 400, 500, and sometimes 1000 cGy per single fraction. These modalities are well documented. It is recommend to change the short term high-dose palliative radiation therapy instead of using conventional palliative radiation therapy in overloading radiotherapy centre, especially for developing country. The reasons are mainly radiation protection aspect, not only for the patients and those who involved with the radiation therapy but also to reduce the unnecessary radiation exposure to the environment. (author)
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Radiation therapy for children: evolving technologies in the era of ALARA
International Nuclear Information System (INIS)
Kun, Larry E.; Beltran, Chris
2009-01-01
The evolution of ever more sophisticated oncologic imaging and technologies providing far more precise radiation therapy have combined to increase the utilization of sophisticated radiation therapy in childhood cancer. For a majority of children with common central nervous system, soft tissue, bone, and dysontogenic neoplasms, local irradiation is fundamental to successful multi-disciplinary management. Along with more precise target volume definition and radiation delivery, new technologies provide added certainty of patient positioning (electronic portal imaging, cone beam CT) and conformality of dose delivery (3-D conformal irradiation, intensity modulated radiation therapy, proton beam therapy). Each of the major areas of technology development are able to better confine the high-dose region to the intended target, but they are also associated with the potential for larger volumes of uninvolved tissues being exposed to low radiation doses. The latter issue plays a role in documented levels of secondary carcinogenesis, sometimes with greater anticipated incidence than that seen in conventional radiation therapy. Parameters related to carcinogenesis, such as dose-volume relationships and neutron contamination that accompanies high-energy photon irradiation and proton therapy, can be identified, sometimes modulated, and accepted as part of the clinical decision process in fine tuning radiation therapy in this more vulnerable age group. (orig.)
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Intensity-Modulated Radiation Therapy (IMRT)
... type your comment or suggestion into the following text box: Comment: E-mail: Area code: Phone no: Thank ... Accelerator Prostate Cancer Treatment Head and Neck Cancer Treatment Introduction to Cancer Therapy (Radiation Oncology) ...
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International Nuclear Information System (INIS)
Rominger, C. Jules; Owen, Jean; Thompson, Phyllis; Giordano, Patricia; Buck, Beverly; Hanks, Gerald
1995-01-01
The shortage of radiation therapists (radiation therapy technologists) has existed in the United States for many years. It now appears the supply may be matching the demand. This report analyzes the data from the most recent manpower study from ACR/ASTRO carried out in 1990 using the Patterns of Care Master Facility list. The report is a comparison of these figures with similar figures published in IJROBP in December, 1983. Between 1980 and 1990 the number of radiation therapists rose from 3096 to 5353, an increase of 72%. During this period of time, the number of radiation therapy machines increased 47%, and the number of patients being treated increased 30%. The total number of educational programs in radiation therapy technology increased from 101 in 1989 to 123 in 1993. The total enrollment in these programs grew from 806 in 1989 to 1591 in 1993. The number of first time examinees in radiation therapy technology by ARRT in 1983 was 387 and increased to 943 in 1994. It is apparent that as a result of the increase in the number of radiation therapy educational programs and the more effective recruitment into these program, the supply of graduating radiation therapists has reached the demand. The future needs for entry level radiation therapists should be based on current data as well as new Blue Book standards that are being developed
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PROTON RADIATION THERAPY: CLINICAL APPLICATION OPPORTUNITIES AND RESEARCH PROSPECTS
Directory of Open Access Journals (Sweden)
M. V. Zabelin
2018-01-01
Full Text Available This article is the review of literature concerning use of proton beam therapy in treatment of oncology. The staticized data on comparison of effi ciency of this method at an eye melanoma are lit. Advantages of proton therapy on the level of local control and depression of frequency of development of the radio induced cataract are refl ected in the provided data. In evident material the technology of preparation and carrying out radiation of an eye is shortly covered with a fascicle of protons. The experience of use of proton therapy of tumors of a skull base got for the last several decades, showed good results. Physical properties of a fascicle of protons allow to achieve the maximum dose conformality, having lowered, thereby, a radial load on the next crucial anatomical structures. The presented material on an oncopediatrics shows insuffi cient knowledge of scientists concerning advantage of a fascicle of protons over modern methods of photon radiation. There are only preliminary clinical results concerning generally of treatment of cranyopharyngiomas. At cancer therapy of a mammary gland, proton therapy showed the best local control of postoperative recurrent tumors, and also depression of a dose load on the contralateral party. The available results of the retrospective analysis of clinical data in the University medical center of Lome Linda, testify to advantages of proton therapy of the localized prostate cancer. The lack of a biochemical recurrence and a local tumoral progression within 5 years after radiation was shown. The data obtained from experience of use of proton radiation therapy with passively scattered fascicle for cancer therapy of a prostate at an early stage showed the admixed results in comparison with modern methods of radiation therapy with the modulated intensity. In treatment of non-small cell cancer of mild advantage of proton therapy aren’t absolutely proved yet. There are data on extreme toxicity of a combination
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The role of radiation therapy in the management of desmoid tumors
International Nuclear Information System (INIS)
Schulz-Ertner, D.; Zierhut, D.; Mende, U.; Harms, W.; Branitzki, P.; Wannenmacher, M.
2002-01-01
Purpose: To investigate the role of radiation therapy (RT) in the management of desmoid tumors. Patients and Methods: Retrospective analysis was performed on 28 patients with desmoid tumors treated with radiation therapy between March 1989 and March 1999. Tumor site was intraabdominal in three, abdominal wall in three and extraabdominal in 22 patients. Median tumor dose was 48 Gy (range 36-60 Gy). Radiation therapy was delivered postoperatively in 26 of 28 patients, two patients received radiation therapy for unresectable recurrent tumors. Results: Median follow-up was 46 months (range 13-108 months). Actuarial 5-year control rate was 73%. We observed six recurrences, located within the radiation field in one patient, out of field in two and at the field margin in three patients. All patients with intraabdominal tumors have been controlled without severe side effects. Conclusions: Radiation therapy is an effective treatment after incomplete resection of desmoid tumors. We did not observe a benefit for tumor doses exceeding 50 Gy. In some patients with circumscribed intraabdominal desmoid tumors, radiation therapy might be a treatment option with low toxicity, if 3-D treatment planning is utilized. (orig.) [de
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START: an advanced radiation therapy information system.
Cocco, A; Valentini, V; Balducci, M; Mantello, G
1996-01-01
START is an advanced radiation therapy information system (RTIS) which connects direct information technology present in the devices with indirect information technology for clinical, administrative, information management integrated with the hospital information system (HIS). The following objectives are pursued: to support decision making in treatment planning and functional and information integration with the rest of the hospital; to enhance organizational efficiency of a Radiation Therapy Department; to facilitate the statistical evaluation of clinical data and managerial performance assessment; to ensure the safety and confidentiality of used data. For its development a working method based on the involvement of all operators of the Radiation Therapy Department, was applied. Its introduction in the work activity was gradual, trying to reuse and integrate the existing information applications. The START information flow identifies four major phases: admission, visit of admission, planning, therapy. The system main functionalities available to the radiotherapist are: clinical history/medical report linking function; folder function; planning function; tracking function; electronic mail and banner function; statistical function; management function. Functions available to the radiotherapy technician are: the room daily list function; management function: to the nurse the following functions are available: patient directing function; management function. START is a departmental client (pc-windows)-server (unix) developed on an integrated database of all information of interest (clinical, organizational and administrative) coherent with the standard and with a modular architecture which can evolve with additional functionalities in subsequent times. For a more thorough evaluation of its impact on the daily activity of a radiation therapy facility, a prolonged clinical validation is in progress.
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Combinations of Radiation Therapy and Immunotherapy for Melanoma: A Review of Clinical Outcomes
International Nuclear Information System (INIS)
Barker, Christopher A.; Postow, Michael A.
2014-01-01
Radiation therapy has long played a role in the management of melanoma. Recent advances have also demonstrated the efficacy of immunotherapy in the treatment of melanoma. Preclinical data suggest a biologic interaction between radiation therapy and immunotherapy. Several clinical studies corroborate these findings. This review will summarize the outcomes of studies reporting on patients with melanoma treated with a combination of radiation therapy and immunotherapy. Vaccine therapies often use irradiated melanoma cells, and may be enhanced by radiation therapy. The cytokines interferon-α and interleukin-2 have been combined with radiation therapy in several small studies, with some evidence suggesting increased toxicity and/or efficacy. Ipilimumab, a monoclonal antibody which blocks cytotoxic T-lymphocyte antigen-4, has been combined with radiation therapy in several notable case studies and series. Finally, pilot studies of adoptive cell transfer have suggested that radiation therapy may improve the efficacy of treatment. The review will demonstrate that the combination of radiation therapy and immunotherapy has been reported in several notable case studies, series and clinical trials. These clinical results suggest interaction and the need for further study
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Combinations of Radiation Therapy and Immunotherapy for Melanoma: A Review of Clinical Outcomes
Energy Technology Data Exchange (ETDEWEB)
Barker, Christopher A., E-mail: barkerc@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Postow, Michael A. [Department of Medicine, Melanoma and Sarcoma Oncology Service, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)
2014-04-01
Radiation therapy has long played a role in the management of melanoma. Recent advances have also demonstrated the efficacy of immunotherapy in the treatment of melanoma. Preclinical data suggest a biologic interaction between radiation therapy and immunotherapy. Several clinical studies corroborate these findings. This review will summarize the outcomes of studies reporting on patients with melanoma treated with a combination of radiation therapy and immunotherapy. Vaccine therapies often use irradiated melanoma cells, and may be enhanced by radiation therapy. The cytokines interferon-α and interleukin-2 have been combined with radiation therapy in several small studies, with some evidence suggesting increased toxicity and/or efficacy. Ipilimumab, a monoclonal antibody which blocks cytotoxic T-lymphocyte antigen-4, has been combined with radiation therapy in several notable case studies and series. Finally, pilot studies of adoptive cell transfer have suggested that radiation therapy may improve the efficacy of treatment. The review will demonstrate that the combination of radiation therapy and immunotherapy has been reported in several notable case studies, series and clinical trials. These clinical results suggest interaction and the need for further study.
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Temporary corneal stem cell dysfunction after radiation therapy
International Nuclear Information System (INIS)
Hiroshi, Fujishima; Kazuo, Tsubota
1996-01-01
Radiation therapy can cause corneal and conjuctival abnormalities that sometimes require surgical treatment. Corneal stem cell dysfunction is described, which recovered after the cessation of radiation. Methods - A 44-year-old man developed a corneal epithelial abnormality associated with conjuctival and corneal inflammation following radiation therapy for maxillary cancer. Examination of brush cytology samples showed goblet cells in the upper and lower parts of the cornea, which showed increased fluorescein permeability, and intraepithelial lymphocytes. Impression cytology showed goblet cells in the same part of the cornea. Specular microscopy revealed spindle type epithelial cells. Patient follow up included artificial tears and an antibiotic ophthalmic ointment. The corneal abnormalities resolved after 4 months with improved visual acuity without any surgical intervention, but the disappearance of the palisades of Vogt did not recover at 1 year after radiation. Radiation therapy in this patient caused temporary stem cell dysfunction which resulted in conjunctivalisation in a part of the cornea. Although limbal stem cell function did not fully recover, this rare case suggested that medical options should be considered before surgery. (Author)
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International Nuclear Information System (INIS)
Matsuura, Keiichi; Miyoshi, Makoto; Jinguu, Ken-ichi
1982-01-01
Of the cases of lung cancer in which radiation therapy was given between 1961 and November 1981, 399 cases for which histological type was confirmed, and irradiated as follows were reviewed. The cases of squamous cell carcinoma and adenocarcinoma irradiated with more than 5,000 rad or more, those of undifferentiated carcinoma irradiated with 3,000 rad or more, and those irradiated pre- and post-operatively with 3,000 rad or more. The actual 5 year survival rate for stages I, II, III and IV were 29.6, 9.3, 7.5 and 1.9% respectively, and the survival rate tended to be better for adenocarcinoma than squamous cell carcinoma at stages I, II and III, but not different at stage IV. There was no difference between large cell, small cell and squamous cell carcinomas. Irradiation with 200 rad every other day or 150 rad daily was better than that with 200 rad, and daily irradiation with 150 rad was used since 1976. The therapy of stage III small cell carcinoma at the age of up to 80 years was improved with the combination of anticancer agents, maintenance therapy and immunotherapy, but these combined therapies were not significantly effective for the cancers with other histological types or at other stages. Although there was no significant difference in statistics for resectable cases, clinically, the results were experienced to be better after resection, and surgery was done in combination as much as possible. (Kaihara, S.)
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Adjuvant Radiation Therapy Treatment Time Impacts Overall Survival in Gastric Cancer
International Nuclear Information System (INIS)
McMillan, Matthew T.; Ojerholm, Eric; Roses, Robert E.; Plastaras, John P.; Metz, James M.; Mamtani, Ronac; Karakousis, Giorgos C.; Fraker, Douglas L.; Drebin, Jeffrey A.; Stripp, Diana; Ben-Josef, Edgar; Datta, Jashodeep
2015-01-01
Purpose: Prolonged radiation therapy treatment time (RTT) is associated with worse survival in several tumor types. This study investigated whether delays during adjuvant radiation therapy impact overall survival (OS) in gastric cancer. Methods and Materials: The National Cancer Data Base was queried for patients with resected gastric cancer who received adjuvant radiation therapy with National Comprehensive Cancer Network–recommended doses (45 or 50.4 Gy) between 1998 and 2006. RTT was classified as standard (45 Gy: 33-36 days, 50.4 Gy: 38-41 days) or prolonged (45 Gy: >36 days, 50.4 Gy: >41 days). Cox proportional hazards models evaluated the association between the following factors and OS: RTT, interval from surgery to radiation therapy initiation, interval from surgery to radiation therapy completion, radiation therapy dose, demographic/pathologic and operative factors, and other elements of adjuvant multimodality therapy. Results: Of 1591 patients, RTT was delayed in 732 (46%). Factors associated with prolonged RTT were non-private health insurance (OR 1.3, P=.005) and treatment at non-academic facilities (OR 1.2, P=.045). Median OS and 5-year actuarial survival were significantly worse in patients with prolonged RTT compared with standard RTT (36 vs 51 months, P=.001; 39 vs 47%, P=.005); OS worsened with each cumulative week of delay (P<.0004). On multivariable analysis, prolonged RTT was associated with inferior OS (hazard ratio 1.2, P=.002); the intervals from surgery to radiation therapy initiation or completion were not. Prolonged RTT was particularly detrimental in patients with node positivity, inadequate nodal staging (<15 nodes examined), and those undergoing a cycle of chemotherapy before chemoradiation therapy. Conclusions: Delays during adjuvant radiation therapy appear to negatively impact survival in gastric cancer. Efforts to minimize cumulative interruptions to <7 days should be considered
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Adjuvant Radiation Therapy Treatment Time Impacts Overall Survival in Gastric Cancer
Energy Technology Data Exchange (ETDEWEB)
McMillan, Matthew T. [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Ojerholm, Eric [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Roses, Robert E., E-mail: Robert.Roses@uphs.upenn.edu [Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Plastaras, John P.; Metz, James M. [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Mamtani, Ronac [Department of Hematology/Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Karakousis, Giorgos C.; Fraker, Douglas L.; Drebin, Jeffrey A. [Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Stripp, Diana; Ben-Josef, Edgar [Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Datta, Jashodeep [Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)
2015-10-01
Purpose: Prolonged radiation therapy treatment time (RTT) is associated with worse survival in several tumor types. This study investigated whether delays during adjuvant radiation therapy impact overall survival (OS) in gastric cancer. Methods and Materials: The National Cancer Data Base was queried for patients with resected gastric cancer who received adjuvant radiation therapy with National Comprehensive Cancer Network–recommended doses (45 or 50.4 Gy) between 1998 and 2006. RTT was classified as standard (45 Gy: 33-36 days, 50.4 Gy: 38-41 days) or prolonged (45 Gy: >36 days, 50.4 Gy: >41 days). Cox proportional hazards models evaluated the association between the following factors and OS: RTT, interval from surgery to radiation therapy initiation, interval from surgery to radiation therapy completion, radiation therapy dose, demographic/pathologic and operative factors, and other elements of adjuvant multimodality therapy. Results: Of 1591 patients, RTT was delayed in 732 (46%). Factors associated with prolonged RTT were non-private health insurance (OR 1.3, P=.005) and treatment at non-academic facilities (OR 1.2, P=.045). Median OS and 5-year actuarial survival were significantly worse in patients with prolonged RTT compared with standard RTT (36 vs 51 months, P=.001; 39 vs 47%, P=.005); OS worsened with each cumulative week of delay (P<.0004). On multivariable analysis, prolonged RTT was associated with inferior OS (hazard ratio 1.2, P=.002); the intervals from surgery to radiation therapy initiation or completion were not. Prolonged RTT was particularly detrimental in patients with node positivity, inadequate nodal staging (<15 nodes examined), and those undergoing a cycle of chemotherapy before chemoradiation therapy. Conclusions: Delays during adjuvant radiation therapy appear to negatively impact survival in gastric cancer. Efforts to minimize cumulative interruptions to <7 days should be considered.
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Oray surgery and radiation therapy
Energy Technology Data Exchange (ETDEWEB)
Carl, W
1975-07-01
Clinical evidence seems to indicate that careful oral surgery after radiation therapy contributes little, if anything at all, to the onset of osteoradionecrosis. In many cases the process of bone dissolution has already well progressed before teeth have to be extracted. The bone changes can be demonstrated radiographically and clinically. The teeth in the immediate area become very mobile and cause severe pain during mastication. Whether this condition could have been prevented by extractions before radiation therapy is difficult to establish. Osteoradionecrosis may be encountered in edentulous jaws. It manifests itself clinically by bone segments which break loose and penetrate through the mucosa leaving a defect which does not heal over. More research and more comparative studies are needed in this area in order to make reasonably accurate predictions.
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Energy Technology Data Exchange (ETDEWEB)
Hu, Yanle, E-mail: Hu.Yanle@mayo.edu [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 and Department of Radiation Oncology, Mayo Clinic in Arizona, Phoenix, Arizona 85054 (United States); Rankine, Leith; Green, Olga L.; Kashani, Rojano; Li, H. Harold; Li, Hua; Rodriguez, Vivian; Santanam, Lakshmi; Wooten, H. Omar; Mutic, Sasa [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Nana, Roger; Shvartsman, Shmaryu; Victoria, James; Dempsey, James F. [ViewRay, Inc., Oakwood Village, Ohio 44146 (United States)
2015-10-15
Purpose: To characterize the performance of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy (MR-IGRT) system. Methods: The imaging performance characterization included four components: ACR (the American College of Radiology) phantom test, spatial integrity, coil signal to noise ratio (SNR) and uniformity, and magnetic field homogeneity. The ACR phantom test was performed in accordance with the ACR phantom test guidance. The spatial integrity test was evaluated using a 40.8 × 40.8 × 40.8 cm{sup 3} spatial integrity phantom. MR and computed tomography (CT) images of the phantom were acquired and coregistered. Objects were identified around the surfaces of 20 and 35 cm diameters of spherical volume (DSVs) on both the MR and CT images. Geometric distortion was quantified using deviation in object location between the MR and CT images. The coil SNR test was performed according to the national electrical manufacturers association (NEMA) standards MS-1 and MS-9. The magnetic field homogeneity test was measured using field camera and spectral peak methods. Results: For the ACR tests, the slice position error was less than 0.10 cm, the slice thickness error was less than 0.05 cm, the resolved high-contrast spatial resolution was 0.09 cm, the resolved low-contrast spokes were more than 25, the image intensity uniformity was above 93%, and the percentage ghosting was less than 0.22%. All were within the ACR recommended specifications. The maximum geometric distortions within the 20 and 35 cm DSVs were 0.10 and 0.18 cm for high spatial resolution three-dimensional images and 0.08 and 0.20 cm for high temporal resolution two dimensional cine images based on the distance-to-phantom-center method. The average SNR was 12.0 for the body coil, 42.9 for the combined torso coil, and 44.0 for the combined head and neck coil. Magnetic field homogeneities at gantry angles of 0°, 30°, 60°, 90°, and 120° were 23.55, 20.43, 18.76, 19
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New three-dimensional moving field radiation therapy for brain tumors
Energy Technology Data Exchange (ETDEWEB)
Mitsuyama, Fuyuki; Kanno, Tetsuo; Nagata, Yutaka; Koga, Sukehiko [Fujita-Gakuen Health Univ., Toyoake, Aichi (Japan); Jain, V K
1992-06-01
A new modified rotation radiation method called 'three-dimensional moving field radiation therapy' is described. The new method uses rotation in many planes while maintaining the same isocenter to achieve a good spatial dose distribution. This delivers a high dose to tumors and spares the surrounding normal structures. This easy method can be carried out using the equipment for conventional rotation radiation therapy. The new method was superior to the one plane rotation radiation therapy using a physical phantom with film, a chemical phantom using the iodine-starch reaction, and a new biological model using tumor cells. Treatment of six brain tumors irradiated with total air doses of 50-60 Gy caused no hair loss or radiation necrosis. (author).
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Some method for teaching physics to residents in radiation therapy
International Nuclear Information System (INIS)
Hughes, D.B.
A method is presented for teaching physics to residents in radiation therapy. Some of the various responsabilities of a hospital physicist are listed, with particular reference to radiation therapy departments [pt
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Perspectives of radiation therapy in benign diseases
International Nuclear Information System (INIS)
Schultze, J.; Eilf, K.
2006-01-01
Purpose: the numbers of patients with nonmalignant diseases referred for radiation therapy had to be evaluated for the last 4 years. Patients and methods: in the years 2002, 2004, and 2005 radiation therapy was performed in 61, 40, and 26 patients, respectively. Regularly, more women than men were treated, median age annually was 57, 54, and 55 years, respectively (table 1). The radiotherapy scheme was not modified within the evaluated period. Results: the proportion of nonmalignant diseases among all patients treated decreased from 4.7% in 2002 to 3.3% in 2004 and 2.2% in 2005, respectively. A shift was noticed toward the treatment of four main diseases (endocrine orbitopathy, prevention of heterotopic ossification, meningeoma, tendinitis, table 2). The number of referring physicians decreased from 19 to six. Conclusion: due to administrative restrictions for treatment in hospitals, budget restrictions in private practices and lasting, insufficient revenues for radiotherapy in nonmalignant diseases, radiation therapy for the entire group of benign diseases is endangered. (orig.)
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Radiation therapy in pseudotumour haemarthrosis
International Nuclear Information System (INIS)
Lal, P.; Biswal, B.M.; Thulkar, S.; Patel, A.K.; Venkatesh, R.; Julka, P.K.
1998-01-01
Total or partial deficiency of factor VIII and IX in the coagulation cascade leads to haemophilia. Haemophilia affecting weight-bearing joints gives a 'pseudotumour' or haemarthrosis-like condition. Surgery and cryoprecipitate infusions have been the treatment for this condition. Radiocolloids and radiation therapy have been used with some benefit. One case of ankle pseudotumour which was treated by low-dose external beam radiation is presented here. Copyright (1998) Blackwell Science Pty Ltd
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Combined therapy of urinary bladder radiation injury
International Nuclear Information System (INIS)
Zaderin, V.P.; Polyanichko, M.F.
1982-01-01
A scheme of therapy of radiation cystitis is suggested. It was developed on the basis of evaluation of literature data and clinical of 205 patients with radiation injury of the urinary bladder. The method is based on general and local therapy of damaged tissues by antiinflammatory drugs, anesthetics and stimulators of reparative regeneration. Severe ulcerative and incrustation cystites, refractory to conservative therapy, were treated by surgery, using antiseptics and reparation stimulators before, during and after operation. As a result, there were hardly any complications after reconstruction of the bladder with intestinal and peritoneal tissues. 104 patients (96.1%) were cured completely and ability to work was restored in 70 patients (76.9%) [ru
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Results of Radiation Therapy in Stage III Uterine Cervical Cancer
Energy Technology Data Exchange (ETDEWEB)
Moon, Chang Woo; Shin, Byung Chul; Yum, Ha Yong; Jeung, Tae Sig; Yoo, Myung Jin [Kosin University College of Medicine, Seoul (Korea, Republic of)
1995-09-15
Purpose : The aim of this study is to analyze the survival rate, treatment failure and complication of radiation therapy alone in stage III uterine cervical cancer. Materials and Methods : From January 1980 through December 1985, 227 patients with stage II uterine cervical cancer treated with radiation therapy at Kosin Medical Center were retrospectively studied. Among 227 patients, 72 patients(31.7%) were stage IIIa, and 155 patients(68.3%) were stage IIIb according to FIGO classification. Age distribution was 32-71 years(median: 62 years). Sixty nine patients(95.8%) in stage IIIa and 150 patients(96.8%) in stage IIIb were squamous cell carcinoma. Pelvic lymph node metastasis at initial diagnosis was 8 patients (11.1%) in stage IIIa and 29 patients(18.7%) in stage IIIb. Among 72 patients with stage IIIa, 36 patients(50%) were treated with external radiation therapy alone by conventional technique (180-200 cGy/fr). And 36 patients(50%) were treated with external radiation therapy with intracavitary radiotherapy(ICR) with Cs137 sources, and among 155 patients with stage IIIb, 80 patients(51.6%) were treated with external radiation therapy alone and 75 patients(48.4%) were treated with external radiation therapy with ICR. Total radiation doses of stage IIIa and IIIb were 65-105 Gy(median : 78.5 Gy) and 65-125.5 Gy (median :83.5 Gy). Survival rate was calculated by life-table method. Results : Complete response rates were 58.3% (42 patients) in state IIIa and 56.1%(87 patients) in stage Iiib. Overall 5 year survival rates were 57% in stage IIIa and 40% in stage IIIb. Five year survival rates by radiation technique in stage IIIa and IIIb were 64%, 40% in group treated in combination of external radiation and ICR, and 50%, 40% in the group of external radiation therapy alone(P=NS). Five year survival rates by response of radiation therapy in stage IIIa and IIIb were 90%, 66% in responder group, and 10%, 7% in non-responder group (P<0.01). There were statistically no
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Results of Radiation Therapy in Stage III Uterine Cervical Cancer
International Nuclear Information System (INIS)
Moon, Chang Woo; Shin, Byung Chul; Yum, Ha Yong; Jeung, Tae Sig; Yoo, Myung Jin
1995-01-01
Purpose : The aim of this study is to analyze the survival rate, treatment failure and complication of radiation therapy alone in stage III uterine cervical cancer. Materials and Methods : From January 1980 through December 1985, 227 patients with stage II uterine cervical cancer treated with radiation therapy at Kosin Medical Center were retrospectively studied. Among 227 patients, 72 patients(31.7%) were stage IIIa, and 155 patients(68.3%) were stage IIIb according to FIGO classification. Age distribution was 32-71 years(median: 62 years). Sixty nine patients(95.8%) in stage IIIa and 150 patients(96.8%) in stage IIIb were squamous cell carcinoma. Pelvic lymph node metastasis at initial diagnosis was 8 patients (11.1%) in stage IIIa and 29 patients(18.7%) in stage IIIb. Among 72 patients with stage IIIa, 36 patients(50%) were treated with external radiation therapy alone by conventional technique (180-200 cGy/fr). And 36 patients(50%) were treated with external radiation therapy with intracavitary radiotherapy(ICR) with Cs137 sources, and among 155 patients with stage IIIb, 80 patients(51.6%) were treated with external radiation therapy alone and 75 patients(48.4%) were treated with external radiation therapy with ICR. Total radiation doses of stage IIIa and IIIb were 65-105 Gy(median : 78.5 Gy) and 65-125.5 Gy (median :83.5 Gy). Survival rate was calculated by life-table method. Results : Complete response rates were 58.3% (42 patients) in state IIIa and 56.1%(87 patients) in stage Iiib. Overall 5 year survival rates were 57% in stage IIIa and 40% in stage IIIb. Five year survival rates by radiation technique in stage IIIa and IIIb were 64%, 40% in group treated in combination of external radiation and ICR, and 50%, 40% in the group of external radiation therapy alone(P=NS). Five year survival rates by response of radiation therapy in stage IIIa and IIIb were 90%, 66% in responder group, and 10%, 7% in non-responder group (P<0.01). There were statistically no
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International Nuclear Information System (INIS)
Hild, Sebastian; Graeff, Christian; Rucinski, Antoni; Zink, Klemens; Habl, Gregor; Durante, Marco; Herfarth, Klaus; Bert, Christoph
2016-01-01
Intensity-modulated particle therapy (IMPT) for tumors showing interfraction motion is a topic of current research. The purpose of this work is to compare three treatment strategies for IMPT to determine potential advantages and disadvantages of ion prostate cancer therapy. Simulations for three treatment strategies, conventional one-plan radiotherapy (ConvRT), image-guided radiotherapy (IGRT), and online adaptive radiotherapy (ART) were performed employing a dataset of 10 prostate cancer patients with six CT scans taken at one week intervals. The simulation results, using a geometric margin concept (7-2 mm) as well as patient-specific internal target volume definitions for IMPT were analyzed by target coverage and exposure of critical structures on single fraction dose distributions. All strategies led to clinically acceptable target coverage in patients exhibiting small prostate motion (mean displacement < 4 mm), but IGRT and especially ART led to significant sparing of the rectum. In 20 % of the patients, prostate motion exceeded 4 mm causing insufficient target coverage for ConvRT (V95 mean = 0.86, range 0.63-0.99) and IGRT (V95 mean = 0.91, range 0.68-1.00), while ART maintained acceptable target coverage. IMPT of prostate cancer demands consideration of rectal sparing and adaptive treatment replanning for patients exhibiting large prostate motion. (orig.) [de
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Radiation Therapy for Lung Cancer
... is almost always due to smoking. TREATING LUNG CANCER Lung cancer treatment depends on several factors, including the ... org TARGETING CANCER CARE Radiation Therapy for Lung Cancer Lung cancer is the second most common cancer in ...
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Roy, Anuradha; Fuller, Clifton D; Rosenthal, David I; Thomas, Charles R
2015-08-28
Comparison of imaging measurement devices in the absence of a gold-standard comparator remains a vexing problem; especially in scenarios where multiple, non-paired, replicated measurements occur, as in image-guided radiotherapy (IGRT). As the number of commercially available IGRT presents a challenge to determine whether different IGRT methods may be used interchangeably, an unmet need conceptually parsimonious and statistically robust method to evaluate the agreement between two methods with replicated observations. Consequently, we sought to determine, using an previously reported head and neck positional verification dataset, the feasibility and utility of a Comparison of Measurement Methods with the Mixed Effects Procedure Accounting for Replicated Evaluations (COM3PARE), a unified conceptual schema and analytic algorithm based upon Roy's linear mixed effects (LME) model with Kronecker product covariance structure in a doubly multivariate set-up, for IGRT method comparison. An anonymized dataset consisting of 100 paired coordinate (X/ measurements from a sequential series of head and neck cancer patients imaged near-simultaneously with cone beam CT (CBCT) and kilovoltage X-ray (KVX) imaging was used for model implementation. Software-suggested CBCT and KVX shifts for the lateral (X), vertical (Y) and longitudinal (Z) dimensions were evaluated for bias, inter-method (between-subject variation), intra-method (within-subject variation), and overall agreement using with a script implementing COM3PARE with the MIXED procedure of the statistical software package SAS (SAS Institute, Cary, NC, USA). COM3PARE showed statistically significant bias agreement and difference in inter-method between CBCT and KVX was observed in the Z-axis (both p - value<0.01). Intra-method and overall agreement differences were noted as statistically significant for both the X- and Z-axes (all p - value<0.01). Using pre-specified criteria, based on intra-method agreement, CBCT was deemed
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Age Disparity in Palliative Radiation Therapy Among Patients With Advanced Cancer
Energy Technology Data Exchange (ETDEWEB)
Wong, Jonathan [University of Hawaii, John A. Burns School of Medicine, Honolulu, Hawaii (United States); Xu, Beibei [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Moores Cancer Center, University of California San Diego, La Jolla, California (United States); Yeung, Heidi N.; Roeland, Eric J. [Moores Cancer Center, University of California San Diego, La Jolla, California (United States); Division of Palliative Medicine, Department of Internal Medicine, University of California San Diego, La Jolla, California (United States); Martinez, Maria Elena [Moores Cancer Center, University of California San Diego, La Jolla, California (United States); Department of Family and Preventive Medicine, University of California San Diego, La Jolla, California (United States); Le, Quynh-Thu [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Mell, Loren K. [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Moores Cancer Center, University of California San Diego, La Jolla, California (United States); Murphy, James D., E-mail: j2murphy@ucsd.edu [Department of Radiation Medicine and Applied Sciences, University of California San Diego, La Jolla, California (United States); Moores Cancer Center, University of California San Diego, La Jolla, California (United States)
2014-09-01
Purpose/Objective: Palliative radiation therapy represents an important treatment option among patients with advanced cancer, although research shows decreased use among older patients. This study evaluated age-related patterns of palliative radiation use among an elderly Medicare population. Methods and Materials: We identified 63,221 patients with metastatic lung, breast, prostate, or colorectal cancer diagnosed between 2000 and 2007 from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Receipt of palliative radiation therapy was extracted from Medicare claims. Multivariate Poisson regression analysis determined residual age-related disparity in the receipt of palliative radiation therapy after controlling for confounding covariates including age-related differences in patient and demographic covariates, length of life, and patient preferences for aggressive cancer therapy. Results: The use of radiation decreased steadily with increasing patient age. Forty-two percent of patients aged 66 to 69 received palliative radiation therapy. Rates of palliative radiation decreased to 38%, 32%, 24%, and 14% among patients aged 70 to 74, 75 to 79, 80 to 84, and over 85, respectively. Multivariate analysis found that confounding covariates attenuated these findings, although the decreased relative rate of palliative radiation therapy among the elderly remained clinically and statistically significant. On multivariate analysis, compared to patients 66 to 69 years old, those aged 70 to 74, 75 to 79, 80 to 84, and over 85 had a 7%, 15%, 25%, and 44% decreased rate of receiving palliative radiation, respectively (all P<.0001). Conclusions: Age disparity with palliative radiation therapy exists among older cancer patients. Further research should strive to identify barriers to palliative radiation among the elderly, and extra effort should be made to give older patients the opportunity to receive this quality of life-enhancing treatment at the end
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Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy
Bednarz, Bryan; Besemer, Abigail
2017-09-01
The use of radionuclide therapy in the clinical setting is expected to increase significantly over the next decade. There is an important need to understand the radiation-induced second cancer risk associated with these procedures. In this study the radiation-induced cancer risk in five radionuclide therapy patients was investigated. These patients underwent serial SPECT imaging scans following injection as part of a clinical trial testing the efficacy of a 131Iodine-labeled radiopharmaceutical. Using these datasets the committed absorbed doses to multiple sensitive structures were calculated using RAPID, which is a novel Monte Carlo-based 3D dosimetry platform developed for personalized dosimetry. The excess relative risk (ERR) for radiation-induced cancer in these structures was then derived from these dose estimates following the recommendations set forth in the BEIR VII report. The radiation-induced leukemia ERR was highest among all sites considered reaching a maximum value of approximately 4.5. The radiation-induced cancer risk in the kidneys, liver and spleen ranged between 0.3 and 1.3. The lifetime attributable risks (LARs) were also calculated, which ranged from 30 to 1700 cancers per 100,000 persons and were highest for leukemia and the liver for both males and females followed by radiation-induced spleen and kidney cancer. The risks associated with radionuclide therapy are similar to the risk associated with external beam radiation therapy.
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Directory of Open Access Journals (Sweden)
Amini Arya
2012-03-01
Full Text Available Abstract Background While conventionally fractionated radiation therapy alone is an acceptable option for poor prognostic patients with unresectable stage III NSCLC, we hypothesized that accelerated hypofractionated radiotherapy will have similar efficacy without increasing toxicity. Methods This is a retrospective analysis of 300 patients diagnosed with stage III NSCLC treated between 1993 and 2009. Patients included in the study were medically or surgically inoperable, were free of metastatic disease at initial workup and did not receive concurrent chemotherapy. Patients were categorized into three groups. Group 1 received 45 Gy in 15 fractions over 3 weeks (Accelerated Radiotherapy (ACRT while group 2 received 60-63 Gy (Standard Radiation Therapy 1 (STRT1 and group 3 received > 63 Gy (Standard Radiation Therapy (STRT2. Results There were 119 (39.7% patients in the ACRT group, 90 (30.0% in STRT1 and 91 (30.3% in STRT2. More patients in the ACRT group had KPS ≤ 60 (p 5% (p = 0.002, and had stage 3B disease (p Conclusions Despite the limitations of a retrospective analysis, our experience of accelerated hypofractionated radiation therapy with 45 Gy in 15 fractions appears to be an acceptable treatment option for poor performance status patients with stage III inoperable tumors. Such a treatment regimen (or higher doses in 15 fractions should be prospectively evaluated using modern radiation technologies with the addition of sequential high dose chemotherapy in stage III NSCLC.
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Radiation therapy of 9L rat brain tumors
International Nuclear Information System (INIS)
Henderson, S.D.; Kimler, B.F.; Morantz, R.A.
1981-01-01
The effects of radiation therapy on normal rats and on rats burdened with 9L brain tumors have been studied. The heads of normal rats were x-irradiated with single exposures ranging from 1000 R to 2700 R. Following acute exposures greater than 2100 R, all animals died in 8 to 12 days. Approximately 30% of the animals survived beyond 12 days over the range of 1850 to 1950 R; following exposures less than 1850 R, all animals survived the acute radiation effects, and median survival times increased with decreasing exposure. Three fractionated radiation schedules were also studied: 2100 R or 3000 R in 10 equal fractions, and 3000 R in 6 equal fractions, each schedule being administered over a 2 week period. The first schedule produced a MST of greater than 1 1/2 years; the other schedules produced MSTs that were lower. It was determined that by applying a factor of 1.9, similar survival responses of normal rats were obtained with single as with fractionated radiation exposures. Animals burdened with 9L gliosarcoma brain tumors normally died of the disease process within 18 to 28 days ater tumor inoculation. Both single and fractionated radiation therapy resulted in a prolongation of survival of tumor-burdened rats. This prolongation was found to be linearly dependent upon the dose; but only minimally dependent upon the time after inoculation at which therapy was initiated, or upon the fractionation schedule that was used. As with normal animals, similar responses were obtained with single as with fractionated exposures when a factor (1.9) was applied. All tumor-bearing animals died prior to the time that death was observed in normal, irradiated rats. Thus, the 9L gliosarcoma rat brain tumor model can be used for the pre-clinical experimental investigation of new therapeutic schedules involving radiation therapy and adjuvant therapies
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Role of radiation therapy for stage III thymoma
International Nuclear Information System (INIS)
Chun, Ha Chung; Lee, Myung Za
2001-01-01
To evaluate the effectiveness and tolerance of the postoperative radiation therapy for patients with Stage III thymoma and to define the optimal radiotherapeutic regimen. We retrospectively analyzed the records of 24 patients with Stage III thymoma who were referred for postoperative radiation therapy in our institution from June, 1987 to May, 1999. Surgical therapy consisted of total resection in one patient, subtotal resection in seventeen, and biopsy alone in six patients. Age of the patients was ranged from 20 to 62 years with mean age of 47 years. Male to female ratio was 14 to 10. Radiation therapy was delivered with linear accelerator producing either 6 MeV or 10 MeV photons. The irradiated volume included anterior mediastinum and known residual disease. The supraclavicular fossae were not irradiated. The delivered total dose was ranged from 30 to 56 Gy. One patient received 30 Gy and eighteen patients received minimum of 50 Gy. Follow up period was ranged from 12 months to 8 years with median follow up of 40 months. The overall local control rate for entire group of patients was 67% at 5 years. The cumulative local failure rates at one, three and five year were 18%, 28% and 33%, respectively. In patients treated with subtotal resection and biopsy alone, local control rate was 76% and 33%, respectively. The actuarial observed survival rate at 5 years was 57%, and actuarial adjusted survival at 5 years was 72%. The difference between 5 year survival rates for patients treated with subtotal resection and biopsy alone was not statistically significant (62% vs 30%). We might conclude that postoperative radiation therapy was safe and effective treatment for patients with Stage III thymoma. Postoperative radiation therapy is recommended in cases where tumor margin is close or incomplete resection is accomplished
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Radiation therapy alone for adenocarcinoma of the uterine cervix
International Nuclear Information System (INIS)
Nakano, Takashi; Arai, Tatsuo; Morita, Shinroku; Oka, Kuniyuki
1995-01-01
Purpose: Radiation therapy alone for adenocarcinoma of the cervix is currently evaluated by the accumulation of long-term results because of the low incidence of this disease. Materials and Methods: Fifty-eight patients with adenocarcinoma of the cervix treated with radiation therapy alone between 1961 and 1988 were studied. The radiation therapy consisted of a combination of intracavitary and external pelvis irradiation. Intracavitary treatment was performed with low dose rate and/or high dose rate sources. Results: The 5-year survival rates for Stages I, II, III, and IV were 85.7%, 66.7%, 32.3%, and 9.1%, respectively, and the 10-year survival rates were 85.7%, 60.0%, 27.6%, and 9.1%, respectively. The local control rate with high dose rate treatment was 45.5%, significantly lower than 85.7% and 72.7% with low and mixed dose rate treatments, respectively. Five-year survival and local control rates by tumor volume were 68.6% and 80.0% for small tumors, 63.6% and 66.0% for medium tumors, and 14.4% and 18.2% for large tumors, respectively. The survival rate and local control rate for large tumors were significantly lower than those for small and medium tumors. Multiple regression analysis indicated that stage and tumor volume were independent variables for survival and local control, respectively. Isoeffective dose expressed by time dose fractionation (TDF) was not associated with local control. Radiation complications developed in 10 patients (17.2%), most of which were of moderate degree. Conclusion: Radiation therapy alone for adenocarcinoma of the cervix was regarded to be an effective treatment, comparable to combination therapy of surgery and radiation therapy
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21 CFR 892.5710 - Radiation therapy beam-shaping block.
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiation therapy beam-shaping block. 892.5710 Section 892.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... block. (a) Identification. A radiation therapy beam-shaping block is a device made of a highly...
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Radiation therapy in pseudotumour haemarthrosis
Energy Technology Data Exchange (ETDEWEB)
Lal, P.; Biswal, B.M.; Thulkar, S.; Patel, A.K.; Venkatesh, R.; Julka, P.K. [Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, Ansari Nagar, New Delhi (India). Departments of Radiation Oncology, Radiodiagnosis and Haematology
1998-11-01
Total or partial deficiency of factor VIII and IX in the coagulation cascade leads to haemophilia. Haemophilia affecting weight-bearing joints gives a `pseudotumour` or haemarthrosis-like condition. Surgery and cryoprecipitate infusions have been the treatment for this condition. Radiocolloids and radiation therapy have been used with some benefit. One case of ankle pseudotumour which was treated by low-dose external beam radiation is presented here. Copyright (1998) Blackwell Science Pty Ltd 14 refs., 2 figs.
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Energy Technology Data Exchange (ETDEWEB)
Trouette, R; Causse, N; Elkhadri, M; Caudry, M; Maire, J P; Houlard, J P; Racaldini, L; Demeaux, H
1995-12-01
Three dimensional conformal radiation therapy would allow to decrease the normal tissue dose while maintaining the same target dose as standard treatment. To evaluate the feasibility of normal tissue dose reduction for ten patients with pneumonectomy for lung cancer, we determined the dose distribution to the normal tissue with 3-dimensional conformal radiation therapy (3-DCRT) and conventional treatment planning (CTP). Dose-volume histograms for target and normal tissue (lung, heart) were used for comparison of the different treatment planning. The mean percentages of lung and heart volumes which received 40 Gy with 3-DCRT were respectively 63% and 37% of the mean percentage of lung and volumes which received the same dose with CTP. These preliminary results suggest that conformal therapy may improve the therapeutic ratio by reducing risk to normal tissue.
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A case of sarcoma of the chest wall after radiation therapy for breast cancer
International Nuclear Information System (INIS)
Izumi, Junko; Nishi, Tsunehiro; Fukuuchi, Atsushi; Takanashi, Riichiro
1998-01-01
A case of radiation-induced sarcoma of the chest wall after radiation therapy for breast cancer is reported. A 69-year-old woman underwent mastectomy with axillary lymph node dissection followed by linac therapy of 50 Gy delivered to the left axilla, left supraclavicular area, and parasternal area. During therapy for bone and liver metastases, a tumor was noted in the left chest wall 15 years after radiation therapy. Incisional biopsy was performed. Histological diagnosis was spindle cell sarcoma. Radiation-induced sarcoma was suspected because the tumor developed 15 years after radiation therapy within the same area. Radiation-induced sarcoma is a rare tumor, but radiation therapy following breast-conserving therapy is widely employed. It is important to be aware of the possibility of radiation-induced sarcoma. (author)
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Sensakovic, William F.; Maxim, Peter; Diehn, Maximilian; Loo, Billy W.; Xing, Lei
2018-01-01
Purpose: The deformable registration of pulmonary computed tomography images before and after radiation therapy is challenging due to anatomic changes from radiation fibrosis. We hypothesize that a line-enhanced registration algorithm can reduce landmark error over the entire lung, including the irradiated regions, when compared to an intensity-based deformable registration algorithm. Materials: Two intensity-based B-spline deformable registration algorithms of pre-radiation therapy and post-radiation therapy images were compared. The first was a control intensity–based algorithm that utilized computed tomography images without modification. The second was a line enhancement algorithm that incorporated a Hessian-based line enhancement filter prior to deformable image registration. Registrations were evaluated based on the landmark error between user-identified landmark pairs and the overlap ratio. Results: Twenty-one patients with pre-radiation therapy and post-radiation therapy scans were included. The median time interval between scans was 1.2 years (range: 0.3-3.3 years). Median landmark errors for the line enhancement algorithm were significantly lower than those for the control algorithm over the entire lung (1.67 vs 1.83 mm; P 5 Gy (2.25 vs 3.31; P 5 Gy dose interval demonstrated a significant inverse relationship with post-radiation therapy fibrosis enhancement after line enhancement filtration (Pearson correlation coefficient = −0.48; P = .03). Conclusion: The line enhancement registration algorithm is a promising method for registering images before and after radiation therapy. PMID:29343206
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Hypothyroidism following surgery and radiation therapy for head and neck cancer
International Nuclear Information System (INIS)
Park, I. K.; Kim, J. C.
1997-01-01
Radiation therapy in combination with surgery has an important role in the therapy of the head and neck cancer. We conducted a prospective study for patients with head and neck cancer treated with surgery and radiation to evaluate the effect of therapies on the thyroid gland, and to identify the factors that might influence the development of hypothyroidism. From September 1986 through December 1994, 71 patients with head and cancer treated with surgery and radiation were included in this prospective study. Patients' age ranged from 32 to 73 years with a median age of 58 years. There were 12 women and 59 men. Total laryngectomy with neck dissection was carried out in 45 patients and neck dissection alone in 26 patients. All patients were serially monitored for thyroid function before and after radiation therapy. Radiation dose to the thyroid gland ranged from 40.6Gy to 60Gy with a median dose of 50Gy. The follow-up duration was 3 to 80 months. The overall incidence of hypothyroidism was 56.3% (40/71); 7 out of 71 patients (9.9%) developed clinical hypothyroidism and 33 patients (46.4%) developed subclinical hypothyroidism. No thyroid nodules, thyroid cancers, or hyperthyroidism was detected. The risk factor that significantly influenced the incidence of hypothyroidism was a combination of surgery (total laryngectomy with neck dissection) and radiation therapy (P=0.0000). Four of 26 patients (15.4%) with neck dissection alone developed hypothyroidism while 36 of 45 patients (80%) with laryngectomy and neck dissection developed hypothyroidism. The hypothyroidism following surgery and radiation therapy was a relatively common complication. The factor that significantly influenced the incidence of hypothyroidism was combination of surgery and radiation therapy. Evaluation of thyroid function before and after radiation therapy with periodic thyroid function tests is recommended for an early detection of hypothyroidism and thyroid hormone replacement therapy is
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Hypothyroidism following surgery and radiation therapy for head and neck cancer
Energy Technology Data Exchange (ETDEWEB)
Park, I. K.; Kim, J. C. [Kyungpook National Univ., Taegu (Korea, Republic of). Coll. of Medicine
1997-09-01
Radiation therapy in combination with surgery has an important role in the therapy of the head and neck cancer. We conducted a prospective study for patients with head and neck cancer treated with surgery and radiation to evaluate the effect of therapies on the thyroid gland, and to identify the factors that might influence the development of hypothyroidism. From September 1986 through December 1994, 71 patients with head and cancer treated with surgery and radiation were included in this prospective study. Patients` age ranged from 32 to 73 years with a median age of 58 years. There were 12 women and 59 men. Total laryngectomy with neck dissection was carried out in 45 patients and neck dissection alone in 26 patients. All patients were serially monitored for thyroid function before and after radiation therapy. Radiation dose to the thyroid gland ranged from 40.6Gy to 60Gy with a median dose of 50Gy. The follow-up duration was 3 to 80 months. The overall incidence of hypothyroidism was 56.3% (40/71); 7 out of 71 patients (9.9%) developed clinical hypothyroidism and 33 patients (46.4%) developed subclinical hypothyroidism. No thyroid nodules, thyroid cancers, or hyperthyroidism was detected. The risk factor that significantly influenced the incidence of hypothyroidism was a combination of surgery (total laryngectomy with neck dissection) and radiation therapy (P=0.0000). Four of 26 patients (15.4%) with neck dissection alone developed hypothyroidism while 36 of 45 patients (80%) with laryngectomy and neck dissection developed hypothyroidism. The hypothyroidism following surgery and radiation therapy was a relatively common complication. The factor that significantly influenced the incidence of hypothyroidism was combination of surgery and radiation therapy. Evaluation of thyroid function before and after radiation therapy with periodic thyroid function tests is recommended for an early detection of hypothyroidism and thyroid hormone replacement therapy is
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Guidelines for safe practice of stereotactic body (ablative) radiation therapy
International Nuclear Information System (INIS)
Foote, Matthew; Barry, Tamara; Bailey, Michael; Smith, Leigh; Seeley, Anna; Siva, Shankar; Hegi-Johnson, Fiona; Booth, Jeremy; Ball, David; Thwaites, David
2015-01-01
The uptake of stereotactic ablative body radiation therapy (SABR) / stereotactic body radiation therapy (SBRT) worldwide has been rapid. The Australian and New Zealand Faculty of Radiation Oncology (FRO) assembled an expert panel of radiation oncologists, radiation oncology medical physicists and radiation therapists to establish guidelines for safe practice of SABR. Draft guidelines were reviewed by a number of international experts in the field and then distributed through the membership of the FRO. Members of the Australian Institute of Radiography and the Australasian College of Physical Scientists and Engineers in Medicine were also asked to comment on the draft. Evidence-based recommendations (where applicable) address aspects of departmental staffing, procedures and equipment, quality assurance measures, as well as organisational considerations for delivery of SABR treatments. Central to the guidelines is a set of key recommendations for departments undertaking SABR. These guidelines were developed collaboratively to provide an educational guide and reference for radiation therapy service providers to ensure appropriate care of patients receiving SABR.
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Technical basis of radiation therapy. Practical clinical applications. 5. ed.
Energy Technology Data Exchange (ETDEWEB)
Levitt, Seymour H. [Karolinska Institutet Stockholm (Sweden). Dept. of Oncol-Pathol; Perez, Carlos A. [Washington Univ. Medical Center, St. Louis, MO (United States). Dept. of Radiation Oncology; Purdy, James A. [California Univ., Sacramento, CA (United States). Dept. of Radiation Oncology; Poortmans, Philip [Institute Verbeeten, Tilburg (Netherlands). Dept. of Radiation Oncology
2012-07-01
This well-received book, now in its fifth edition, is unique in providing a detailed description of the technological basis of radiation therapy. Another novel feature is the collaborative writing of the chapters by North American and European authors. This considerably broadens the book's perspective and increases its applicability in daily practice throughout the world. The book is divided into two sections. The first covers basic concepts in treatment planning, including essential physics and biological principles related to time-dose-fractionation, and explains the various technological approaches to radiation therapy, such as intensity-modulated radiation therapy, tomotherapy, stereotactic radiotherapy, and high and low dose rate brachytherapy. Issues relating to quality assurance, technology assessment, and cost-benefit analysis are also reviewed. The second part of the book discusses in depth the practical clinical applications of the different radiation therapy techniques in a wide range of cancer sites. All of the chapters have been written by leaders in the field. This book will serve to instruct and acquaint teachers, students, and practitioners in the various fields of oncology with the basic technological factors and approaches in radiation therapy. (orig.)
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International Nuclear Information System (INIS)
Yue Jinbo; Yu Jinming; Liu Jing; Liu Tonghai; Yin Yong; Shi Xuetao; Song Jinlong
2007-01-01
Objective: To define the planning target volume(PTV) margin with an active breathing control (ABC) and the Varian image-guided radiotherapy (IGRT) system. Methods: Thirteen patients with liver cancer were treated with radiotherapy from May 2006 to September 2006. Prior to radiotherapy, all patients had undergone transarterial chemoembolization (TACE) by infusing a mixture of iodized oil contrast medium and chemotherapeutic agents, kV fluoroscopy was used to measure the potential motion of lipiodol spot positions during ABC breath-holds. ABC was used for planning CT scan and radiation delivery, with the breath held at the same phase of the respiratory cycle (near end-exhalation). Cone beam CT (CBCT) was taken using Varian IGRT system, which was then compared online with planning CT using a 3 D-3 D matching tool. Analysis relied on lipiodol spots on planning CT and CBCT manually. The treatment table was moved to produce acceptable setup before treatment delivery. Repeated CBCT image and another analysis were obtained after irradiation. Results: No motion of the intrahepatic tumor was observed on fluoroscopy during ABC breath-holds. The estimated required PTV margins, calculated according to the Stroom formula, were 4.4 mm, 5.3 mm and 7.8 mm in the x, y and z axis directions before radiotherapy. The corresponding parameters were 2.5m, 2.6 mm and 3.9 mm after radiotherapy. Conclusions: We have adopted a PTV margin of 5 mm, 6 mm and 8 mm in the x, y and z axis directions with ABC, and 3,3 and 4 mm with ABC and on-line kilovoltage CBCT. (authors)
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Energy Technology Data Exchange (ETDEWEB)
Hu, Y; Mutic, S; Du, D; Green, O [Washington University School of Medicine, Saint Louis, MO (United States); Zeng, Q; Nana, R; Patrick, J; Shvartsman, S; Dempsey, J [ViewRay Incorporated, Oakwood Village, OH (United States)
2014-06-15
Purpose: To evaluate the feasibility of using the weighted hybrid iterative spiral k-space encoded estimation (WHISKEE) technique to improve spatial resolution of tracking images for onboard MR image guided radiation therapy (MR-IGRT). Methods: MR tracking images of abdomen and pelvis had been acquired from healthy volunteers using the ViewRay onboard MRIGRT system (ViewRay Inc. Oakwood Village, OH) at a spatial resolution of 2.0mm*2.0mm*5.0mm. The tracking MR images were acquired using the TrueFISP sequence. The temporal resolution had to be traded off to 2 frames per second (FPS) to achieve the 2.0mm in-plane spatial resolution. All MR images were imported into the MATLAB software. K-space data were synthesized through the Fourier Transform of the MR images. A mask was created to selected k-space points that corresponded to the under-sampled spiral k-space trajectory with an acceleration (or undersampling) factor of 3. The mask was applied to the fully sampled k-space data to synthesize the undersampled k-space data. The WHISKEE method was applied to the synthesized undersampled k-space data to reconstructed tracking MR images at 6 FPS. As a comparison, the undersampled k-space data were also reconstructed using the zero-padding technique. The reconstructed images were compared to the original image. The relatively reconstruction error was evaluated using the percentage of the norm of the differential image over the norm of the original image. Results: Compared to the zero-padding technique, the WHISKEE method was able to reconstruct MR images with better image quality. It significantly reduced the relative reconstruction error from 39.5% to 3.1% for the pelvis image and from 41.5% to 4.6% for the abdomen image at an acceleration factor of 3. Conclusion: We demonstrated that it was possible to use the WHISKEE method to expedite MR image acquisition for onboard MR-IGRT systems to achieve good spatial and temporal resolutions simultaneously. Y. Hu and O. green
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International Nuclear Information System (INIS)
Hu, Y; Mutic, S; Du, D; Green, O; Zeng, Q; Nana, R; Patrick, J; Shvartsman, S; Dempsey, J
2014-01-01
Purpose: To evaluate the feasibility of using the weighted hybrid iterative spiral k-space encoded estimation (WHISKEE) technique to improve spatial resolution of tracking images for onboard MR image guided radiation therapy (MR-IGRT). Methods: MR tracking images of abdomen and pelvis had been acquired from healthy volunteers using the ViewRay onboard MRIGRT system (ViewRay Inc. Oakwood Village, OH) at a spatial resolution of 2.0mm*2.0mm*5.0mm. The tracking MR images were acquired using the TrueFISP sequence. The temporal resolution had to be traded off to 2 frames per second (FPS) to achieve the 2.0mm in-plane spatial resolution. All MR images were imported into the MATLAB software. K-space data were synthesized through the Fourier Transform of the MR images. A mask was created to selected k-space points that corresponded to the under-sampled spiral k-space trajectory with an acceleration (or undersampling) factor of 3. The mask was applied to the fully sampled k-space data to synthesize the undersampled k-space data. The WHISKEE method was applied to the synthesized undersampled k-space data to reconstructed tracking MR images at 6 FPS. As a comparison, the undersampled k-space data were also reconstructed using the zero-padding technique. The reconstructed images were compared to the original image. The relatively reconstruction error was evaluated using the percentage of the norm of the differential image over the norm of the original image. Results: Compared to the zero-padding technique, the WHISKEE method was able to reconstruct MR images with better image quality. It significantly reduced the relative reconstruction error from 39.5% to 3.1% for the pelvis image and from 41.5% to 4.6% for the abdomen image at an acceleration factor of 3. Conclusion: We demonstrated that it was possible to use the WHISKEE method to expedite MR image acquisition for onboard MR-IGRT systems to achieve good spatial and temporal resolutions simultaneously. Y. Hu and O. green
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The synergistic effect of nanoparticles in photodynamic therapy and radiation therapy
International Nuclear Information System (INIS)
Chen Na; Tu Yu; Zhang Xuguang
2010-01-01
This paper describes a novel treatment: based on nanoparticles that combines radiotherapy and photodynamic therapy. With this approach, the application of traditional photodynamic therapies only to surface treatment can be solved, so that the therapeutic effect can be improved; the approach also could guarantee the effectiveness of treatment and reduce radiation doses, so it can effectively control the complications of radiotherapy, This new modality will open a new chapter for cancer therapy. (authors)
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The concept and evolution of involved site radiation therapy for lymphoma
DEFF Research Database (Denmark)
Specht, Lena; Yahalom, Joachim
2015-01-01
We describe the development of radiation therapy for lymphoma from extended field radiotherapy of the past to modern conformal treatment with involved site radiation therapy based on advanced imaging, three-dimensional treatment planning and advanced treatment delivery techniques. Today, radiation...... therapy is part of the multimodality treatment of lymphoma, and the irradiated tissue volume is much smaller than before, leading to highly significant reductions in the risks of long-term complications....
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International Nuclear Information System (INIS)
Hazard, Lisa J.; Sause, William T.; Noyes, R. Dirk
2002-01-01
Purpose: Surgically resected melanoma patients with high-risk features commonly receive adjuvant therapy with interferon-alpha 2b combined with radiation therapy; the purpose of our study was to evaluate the potential enhancement of radiation toxicity by interferon. Methods and Materials: Patients at LDS Hospital and the University of Utah Medical Center in Salt Lake City treated with interferon during radiotherapy or within 1 month of its completion were retrospectively identified, and their charts were reviewed. If possible, the patients were asked to return to the LDS Hospital radiation therapy department for follow-up. Results: Five of 10 patients receiving interferon-alpha 2b therapy during radiation therapy or within 1 month of its completion experienced severe subacute/late complications of therapy. Severe subacute/late complications included two patients with peripheral neuropathy, one patient with radiation necrosis in the brain, and two patients with radiation necrosis in the s.c. tissue. One patient with peripheral neuropathy and one patient with radiation necrosis also developed lymphedema. Conclusions: In vitro studies have identified a radiosensitizing effect by interferon-alpha on certain cell lines, which suggests the possibility that patients treated with interferon and radiation therapy may experience more severe radiation toxicities. We have observed severe subacute/late complications in five of 10 patients treated with interferon-alpha 2b during radiation therapy or within 1 month of its completion. Although an observational study of 10 patients lacks the statistic power to reach conclusions regarding the safety and complication rates of combined interferon and radiation therapy, it is sufficient to raise concerns and suggest the need for prospective studies
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International Nuclear Information System (INIS)
Wu, Q; Pei, X; Cao, R; Hu, L; Wu, Y
2014-01-01
Purpose: The purpose of this work was to develop a registration framework and method based on the software platform of ARTS-IGRT and implement in C++ based on ITK libraries to register CT images and CBCT images. ARTS-IGRT was a part of our self-developed accurate radiation planning system ARTS. Methods: Mutual information (MI) registration treated each voxel equally. Actually, different voxels even having same intensity should be treated differently in the registration procedure. According to their importance values calculated from self-information, a similarity measure was proposed which combined the spatial importance of a voxel with MI (S-MI). For lung registration, Firstly, a global alignment method was adopted to minimize the margin error and achieve the alignment of these two images on the whole. The result obtained at the low resolution level was then interpolated to become the initial conditions for the higher resolution computation. Secondly, a new similarity measurement S-MI was established to quantify how close the two input image volumes were to each other. Finally, Demons model was applied to compute the deformable map. Results: Registration tools were tested for head-neck and lung images and the average region was 128*128*49. The rigid registration took approximately 2 min and converged 10% faster than traditional MI algorithm, the accuracy reached 1mm for head-neck images. For lung images, the improved symmetric Demons registration process was completed in an average of 5 min using a 2.4GHz dual core CPU. Conclusion: A registration framework was developed to correct patient's setup according to register the planning CT volume data and the daily reconstructed 3D CBCT data. The experiments showed that the spatial MI algorithm can be adopted for head-neck images. The improved Demons deformable registration was more suitable to lung images, and rigid alignment should be applied before deformable registration to get more accurate result. Supported by
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International Nuclear Information System (INIS)
Nishimura, Reiki; Nagao, Kazuharu; Miyayama, Haruhiko
1999-01-01
Significant risk factors for recurrence of breast cancer after breast-conserving therapy, which has become a standard treatment for breast cancer, are positive surgical margins and the failure to perform radiation therapy. In this study, we evaluated the clinical significance of radiation therapy after primary surgery or breast recurrence. In 344 cases of breast-conserving surgery, disease recurred in 43 cases (12.5%), which were classified as follows: 17 cases of breast recurrence, 13 cases of breast and distant metastasis, and 13 cases of distant metastasis. Sixty-two patients (16.7%) received radiation therapy. A positive surgical margin and younger age were significant risk factors for breast recurrence in patients not receiving postoperative radiation therapy but not in patients receiving radiation therapy. Radiation therapy may be beneficial for younger patients with positive surgical margins. Furthermore, radiation therapy after recurrence was effective in the cases not treated with postoperative radiation but not in cases with inflammatory recurrence. Patients with breast recurrence alone had significantly higher survival rates than did patients with distant metastases regardless of breast recurrence. These findings suggest that the adaptation criteria of radiation therapy for local control must be clarified. (author)
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Energy Technology Data Exchange (ETDEWEB)
Nishimura, Reiki; Nagao, Kazuharu; Miyayama, Haruhiko [Kumamoto City Hospital (Japan)] [and others
1999-03-01
Significant risk factors for recurrence of breast cancer after breast-conserving therapy, which has become a standard treatment for breast cancer, are positive surgical margins and the failure to perform radiation therapy. In this study, we evaluated the clinical significance of radiation therapy after primary surgery or breast recurrence. In 344 cases of breast-conserving surgery, disease recurred in 43 cases (12.5%), which were classified as follows: 17 cases of breast recurrence, 13 cases of breast and distant metastasis, and 13 cases of distant metastasis. Sixty-two patients (16.7%) received radiation therapy. A positive surgical margin and younger age were significant risk factors for breast recurrence in patients not receiving postoperative radiation therapy but not in patients receiving radiation therapy. Radiation therapy may be beneficial for younger patients with positive surgical margins. Furthermore, radiation therapy after recurrence was effective in the cases not treated with postoperative radiation but not in cases with inflammatory recurrence. Patients with breast recurrence alone had significantly higher survival rates than did patients with distant metastases regardless of breast recurrence. These findings suggest that the adaptation criteria of radiation therapy for local control must be clarified. (author)
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International Nuclear Information System (INIS)
Rocha, N.K.S.; Filipov, D.; Soboll, D.S.
2017-01-01
It is a retrospective study that analyzed positional fluctuations of 29 patients submitted to prostate radiotherapy, using IGRT. The minimum and maximum averages of the lateral, longitudinal and vertical displacements were calculated, obtaining a general average of the displacements that remained close to zero and one the most evident variation between the lateral and vertical axes
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Alterations of nutritional status: impact of chemotherapy and radiation therapy
International Nuclear Information System (INIS)
Donaldson, S.S.; Lenon, R.A.
1979-01-01
The nutritional status of a cancer patient may be affected by the tumor, the chemotherapy and/or radiation therapy directed against the tumor, and by complications associated with that therapy. Chemotherpay-radiotherapy is not confined exclusively to malignant cell populations; thus, normal tissues may also be affected by the therapy and may contribute to specific nutritional problems. Impaired nutrition due to anorexia, mucositis, nausea, vomiting, and diarrhea may be dependent upon the specific chemotherapeutic agent, dose, or schedule utilized. Similar side effects from radiation therapy depend upon the dose, fractionation, and volume irradiated. When combined modality treatment is given the nutritional consequences may be magnified. Prospective, randomized clinical trials are underway to investigate the efficacy of nutritional support during chemotherapy-radiotherapy on tolerance to treatment, complications from treatment, and response rates to treatment. Preliminary results demonstrate that the administration of total parenteral nutrition is successful in maintaining weight during radiation therapy and chemotherapy, but that weight loss occurs after discontinuation of nutritional support. Thus, longterm evaluation is mandatory to learn the impact of nutritional support on survival, diease-free survival, and complication rates, as well as on the possible prevention of morbidity associated with aggressive chemotherapy-radiation therapy
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Radiation therapy for head and neck cancers
International Nuclear Information System (INIS)
Gillette, S.M.; Gillette, E.L.
1995-01-01
Radiation therapy may be indicated for larger invasive tumors of the head and neck that may be difficult to surgically excise or for which surgery would be significantly disfiguring. Previous studies of oral squamous cell carcinomas indicate that it should be possible to control approximately 80% of all but the most advanced local or locoregional tumors. Aggressive radiation therapy to total doses of 56 Gy or greater may be required. That can be done by using smaller doses per fraction and gradually reducing the size of the field so that the highest dose is given only to the tumor with a relatively tight margin. Malignant melanomas can be controlled locally apparently with a few large fractions. Metastatic disease limits survival; therefore, some type of systemic therapy seems to be needed to improve survival of those patients. Canine oral fibrosarcomas require a very high dose for a reasonable probability of control. It seems that a dose of 56 Gy given in 3.3 Gy fractions might provide local control of 50% of the tumors. It is likely that a combination of surgery and radiation would significantly improve the probability for control. Oral squamous cell carcinomas of cats must also be treated very aggressively to improve local control. Tumors of the nasal cavity are usually very large and invasive at the time of diagnosis. Radiation therapy has been shown to be effective in some instances. It is possible that with better definition of the tumor through computerized tomography imaging and improved treatment planning, control of these difficult to manage nasal tumors can be improved
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Stroke After Radiation Therapy for Head and Neck Cancer: What Is the Risk?
Energy Technology Data Exchange (ETDEWEB)
Arthurs, Erin [Department of Public Health Sciences, Queen' s University, Kingston, Ontario (Canada); Hanna, Timothy P. [Division of Cancer Care and Epidemiology, Queen' s University, Kingston, Ontario (Canada); Department of Oncology, Queen' s University, Kingston, Ontario (Canada); Zaza, Khaled [Department of Oncology, Queen' s University, Kingston, Ontario (Canada); Peng, Yingwei [Department of Public Health Sciences, Queen' s University, Kingston, Ontario (Canada); Hall, Stephen F., E-mail: sfh@queensu.ca [Division of Cancer Care and Epidemiology, Queen' s University, Kingston, Ontario (Canada); Department of Otolaryngology, Queen' s University, Kingston, Ontario (Canada)
2016-11-01
Purpose: A retrospective population-based cohort study was conducted to determine the risk of ischemic stroke with respect to time, associated with curative radiation therapy in head and neck squamous cell carcinomas (HNSCC). Methods and Materials: On the basis of data from the Ontario Cancer Registry and regional cancer treatment centers, 14,069 patients were identified with diagnoses of squamous cell carcinoma of the oral cavity, larynx, and pharynx who were treated for cure between 1990 and 2010. Hazards of stroke and time to stroke were examined, accounting for the competing risk of death. Stroke risk factors identified through diagnostic and procedural administrative codes were adjusted for in the comparison between treatment regimens, which included surgery alone versus radiation therapy alone and surgery alone versus any exposure to radiation therapy. Results: Overall, 6% of patients experienced an ischemic stroke after treatment, with 5% experiencing a stroke after surgery, 8% after radiation therapy alone, and 6% after any exposure to radiation therapy. The cause-specific hazard ratios of ischemic stroke after radiation therapy alone and after any exposure to radiation therapy compared with surgery were 1.70 (95% confidence interval [CI]: 1.41-2.05) and 1.46 (95% CI: 1.23-1.73), respectively, after adjustment for stroke risk factors, patient factors, and disease-related factors. Conclusions: Radiation therapy was associated with an increased risk of ischemic stroke compared with surgery alone: for both radiation therapy alone and after all treatment modalities that included any radiation treatment were combined. Because of a shift toward a younger HNSCC patient population, our results speak to the need for adequate follow-up and survivorship care among patients who have been treated with radiation therapy. Advances in treatment that minimize chronic morbidity also require further evaluation.
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International Nuclear Information System (INIS)
Tai, A; Ahunbay, E; Li, X
2014-01-01
Purpose: To develop a method to create ventilation CTs from daily 4D CTs or 4D KV conebeam CTs (4DCBCT) acquired during image-guided radiation therapy (IGRT) for thoracic tumors, and to explore the potential for using the ventilation CTs as a means for early detection of lung injury during radiation treatment. Methods: 4DCT acquired using an in-room CT (CTVision, Siemens) and 4DCBCT acquired using the X-ray Volume Imaging (XVI) system (Infinity, Elekta) for representative lung cancer patients were analyzed. These 4D data sets were sorted into 10 phase images. A newly-available deformable image registration tool (ADMIRE, Elekta) is used to deform the phase images at the end of exhale (EE) to the phase images at the end of inhale (EI). The lung volumes at EI and EE were carefully contoured using an intensity-based auto-contour tool and then manually edited. The ventilation images were calculated from the variations of CT numbers of those voxels masked by the lung contour at EI between the registered phase images. The deformable image registration is also performed between the daily 4D images and planning 4DCT, and the resulting deformable field vector (DFV) is used to deform the planning doses to the daily images by an in-house Matlab program. Results: The ventilation images were successfully created. The tide volumes calculated using the ventilation images agree with those measured through volume difference of contours at EE and EI, indicating the accuracy of ventilation images. The association between the delivered doses and the change of lung ventilation from the daily ventilation CTs is identified. Conclusions: A method to create the ventilation CT using daily 4DCTs or 4D KV conebeam CTs was developed and demonstrated
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Oxygenation of spontaneous canine tumors during fractionated radiation therapy
International Nuclear Information System (INIS)
Achermann, R.E.; Ohlerth, S.M.; Bley, C.R.; Inteeworn, N.; Schaerz, M.; Wergin, M.C.; Kaser-Hotz, B.; Gassmann, M.; Roos, M.
2004-01-01
Background and purpose: tumor oxygenation predicts treatment outcome, and reoxygenation is considered important in the efficacy of fractionated radiation therapy. Therefore, the purpose of this study was to document the changes of the oxygenation status in spontaneous canine tumors during fractionated radiation therapy using polarographic needle electrodes. Material and methods: tumor oxygen partial pressure (pO 2 ) measurements were performed with the eppendorf-pO 2 -Histograph. The measurements were done under general anesthesia, and probe tracks were guided with ultrasound. pO 2 was measured before radiation therapy in all dogs. In patients treated with curative intent, measurements were done sequentially up to eight times (total dose: 45-59.5 Gy). Oxygenation status of the palliative patient group was examined before each fraction of radiation therapy up to five times (total dose: 24-30 Gy). Results: 15/26 tumors had a pretreatment median pO 2 ≤ 10 mmHg. The pO 2 values appeared to be quite variable in individual tumors during fractionated radiation therapy. The pO 2 of initially hypoxic tumors (pretreatment median pO 2 ≤ 10 mmHg) remained unchanged during fractionated radiotherapy, whereas in initially normoxic tumors the pO 2 decreased. Conclusion: hypoxia is common in spontaneous canine tumors, as 57.7% of the recorded values were ≥ 10 mmHg. The data of this study showed that initially hypoxic tumors remained hypoxic, whereas normoxic tumors became more hypoxic. (orig.)
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International Nuclear Information System (INIS)
Thongphiew, Danthai; Wu, Q. Jackie; Lee, W. Robert; Chankong, Vira; Yoo, Sua; McMahon, Ryan; Yin Fangfang
2009-01-01
This study compares three online image guidance techniques (IGRT) for prostate IMRT treatment: bony-anatomy matching, soft-tissue matching, and online replanning. Six prostate IMRT patients were studied. Five daily CBCT scans from the first week were acquired for each patient to provide representative ''snapshots'' of anatomical variations during the course of treatment. Initial IMRT plans were designed for each patient with seven coplanar 15 MV beams on a Eclipse treatment planning system. Two plans were created, one with a PTV margin of 10 mm and another with a 5 mm PTV margin. Based on these plans, the delivered dose distributions to each CBCT anatomy was evaluated to compare bony-anatomy matching, soft-tissue matching, and online replanning. Matching based on bony anatomy was evaluated using the 10 mm PTV margin (''bone10''). Soft-tissue matching was evaluated using both the 10 mm (''soft10'') and 5 mm (''soft5'') PTV margins. Online reoptimization was evaluated using the 5 mm PTV margin (''adapt''). The replanning process utilized the original dose distribution as the basis and linear goal programming techniques for reoptimization. The reoptimized plans were finished in less than 2 min for all cases. Using each IGRT technique, the delivered dose distribution was evaluated on all 30 CBCT scans (6 patientsx5CBCT/patient). The mean minimum dose (in percentage of prescription dose) to the CTV over five treatment fractions were in the ranges of 99%-100%(SD=0.1%-0.8%), 65%-98%(SD=0.4%-19.5%), 87%-99%(SD=0.7%-23.3%), and 95%-99%(SD=0.4%-10.4%) for the adapt, bone10, soft5, and soft10 techniques, respectively. Compared to patient position correction techniques, the online reoptimization technique also showed improvement in OAR sparing when organ motion/deformations were large. For bladder, the adapt technique had the best (minimum) D90, D50, and D30 values for 24, 17, and 15 fractions out of 30 total fractions, while it also had the best D90, D50, and D30 values for
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Risk of secondary malignancies after radiation therapy for breast cancer: Comprehensive results.
Burt, Lindsay M; Ying, Jian; Poppe, Matthew M; Suneja, Gita; Gaffney, David K
2017-10-01
To assess risks of secondary malignancies in breast cancer patients who received radiation therapy compared to patients who did not. The SEER database was used to identify females with a primary diagnosis of breast cancer as their first malignancy, during 1973-2008. We excluded patients with metastatic disease, age breast cancer recurrence, or who developed a secondary malignancy within 1 year of diagnosis. Standardized incidence ratios and absolute excess risk were calculated using SEER*Stat, version 8.2.1 and SAS, version 9.4. There were 374,993 patients meeting the inclusion criteria, with 154,697 who received radiation therapy. With a median follow-up of 8.9 years, 13% of patients (49,867) developed a secondary malignancy. The rate of secondary malignancies was significantly greater than the endemic rate in breast cancer patients treated without radiation therapy, (O/E 1.2, 95% CI 1.19-1.22) and with radiation therapy (O/E 1.33, 95% CI 1.31-1.35). Approximately 3.4% of secondary malignancies were attributable to radiation therapy. The increased risk of secondary malignancies in breast cancer patients treated with radiation therapy compared to those without was significant regardless of age at breast cancer diagnosis (p breast cancer patients both with and without radiation therapy compared to the general population. There was an increased risk in specific sites for patients treated with radiation therapy. This risk was most evident in young patients and who had longer latency periods. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Determinants of job satisfaction among radiation therapy faculty.
Swafford, Larry G; Legg, Jeffrey S
2009-01-01
Job satisfaction is one of the most significant predictors of employee retention in a variety of occupational settings, including health care and education. A national survey of radiation therapy educators (n = 90) has indicated that respondents are not satisfied with their jobs based on data collected using the Minnesota Satisfaction Questionnaire (MSQ). To predict the factors associated with job satisfaction or dissatisfaction, the authors used a nine-item questionnaire derived from the MSQ. Educators were grouped according to their job satisfaction scores, and multiple discriminant analysis was used to determine which factors were predictive of satisfaction among groups of educators. Statistical results indicate that ability utilization, institutional support, compensation, personnel, and job characteristics were key determinants of job satisfaction among radiation therapy educators. These results may better inform faculty and administration of important factors that can promote job satisfaction and retain faculty in radiation therapy education programs.
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A computer based learning program for radiation therapy
International Nuclear Information System (INIS)
Frenzel, T.; Kruell, A.; Schmidt, R.
1999-01-01
Many textbooks about radiation therapy for the education of medical, technical and scientific staff are available. But they are restricted to transfer of knowledge via text and figures. On the other hand movies and animated pictures can give you a more realistic impression of the procedures and technical equipment of a radiation therapy department. Therefore, an interactive multimedia teaching program was developed at the Universitaets-Krankenhaus Eppendorf for the department of radiation therapy. The electronic textbook runs under 'MS Windows 3.1 trademark ' (with multimedia extensions) and 'MS Windows 95 trademark ', contains eight chapters and can be used without any preliminary knowledge. The program has been tested by medical personnel, nurses, physicists and physicians and was generally welcome. The program was designed for people with different levels of education to reach as many users as possible. It was not created to replace textbooks but was designed for their supplement. (orig.) [de
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Radiation therapy apparatus having retractable beam stopper
International Nuclear Information System (INIS)
Coad, G.L.
1983-01-01
This invention relates to a radiation therapy apparatus which utilized a linear translation mechanism for positioning a beam stopper. An apparatus is described wherein the beam stopper is pivotally attached to the therapy machine with an associated drive motor in such a way that the beam stopper retracts linearly
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International Nuclear Information System (INIS)
Syimonova, L.Yi.; Gertman, V.Z.; Byilogurova, L.V.; Kulyinyich, G.V.; Lavrik, V.P.
2012-01-01
The authors report preliminary findings of the investigation of the effect of combination photon-magnetic therapy with successive application of red and blue light to the skin of breast cancer patients during the course of post-operative radiation therapy. It was established that photonmagnetic therapy positively influenced the state of the skin in the irradiated areas. Addition of the magnetic factor significantly improved the efficacy of phototherapy. The patients receiving photon-magnetic therapy finished the course of radiation therapy with almost unchanged skin.
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Radiation therapy for primary spinal cord tumors in adults
International Nuclear Information System (INIS)
Jeremic, B.; Grujicic, D.; Jovanovic, D.; Djuric, L.; Mijatovic, L.
1990-01-01
This paper evaluates the role of radiation therapy in management of primary spinal cord tumors in adults. Records of 21 patients with primary spinal cord tumors treated with radiation therapy after surgery were retrospectively reviewed. Histologic examination showed two diffuse and 10 localized ependymomas, six low-grade gliomas, and three malignant gliomas. Surgery consisted of gross tumor resection in six patients, subtotal resection in three patients, and biopsy in 12 patients. Three patients also received chemotherapy. Radiation dose range from 45 to 55 Cy
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Radiation therapy for cancer in elderly patients over 80 years of age
International Nuclear Information System (INIS)
Nozaki, Miwako; Murakami, Yuko; Furuta, Masaya; Izawa, Yasuyuki; Iwasaki, Naoya
1998-01-01
The elderly population has recently increased, and the need for cancer care and treatment for the elderly is likely to grow. We report on radiation therapy for cancer in elderly patients over 80 years of age. During the period from 1985 to 1996, 90 elderly patients (54 men, 36 women) aged over 80 years were treated with radiation therapy. Many patients had primary tumors of the esophagus, head and neck, and lungs, in that order of frequency. Fifty-seven percent of the patients were treated with radical radiotherapy, and 70% were treated with radiotherapy alone. The rate of completion of radiation therapy was 90%, and the response rate was 82%. Radiation therapy played an important role in the treatment of the patients over 80 years of age. The half of our patients had concurrent medical problems, and were dependent on their home physicians both before and after radiation therapy. We consider that radiation oncologists should make an effort to form a good relationship with home physicians. (author)
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International Nuclear Information System (INIS)
Bolderston, Amanda
2008-01-01
Objectives: The purpose of this study was to discover and compare radiation therapy patients' and radiation therapists' perceptions of patients' educational topics of interest and methods of information delivery during a course of radiation therapy. Methods: Using Likert-type 4-point rating scales, 42 therapists and 183 radiation therapy patients were surveyed to rate the degree of importance of 15 informational items (for example, 'What it feels like to have treatment'). In addition, therapists and patients ranked 11 methods of informational delivery (for example, 'Watching video tapes') in order of preference. Results: Results indicated several differences in therapists' and patients' perceptions of both the educational topics of interest and methods of information delivery. Among other things, patients assigned high importance to after treatment issues ('What happens after radiation therapy is finished') and how radiation therapy works, these areas were not seen as important by the studied therapists. Patients expressed a strong preference for receiving information about radiation therapy from their family doctor (ranked third), therapists ranked this source of information as the least important. Conclusion: It is vital to tailor educational interventions according to the patient's preference to optimize both understanding and compliance. This study demonstrated noteworthy differences in several areas between therapists' and patients' perceptions. Recommendations therefore include raising therapist's awareness of topics that are important to patients and meaningful informational delivery methods
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Radiation therapy services in South Africa
African Journals Online (AJOL)
available were pooled according to health regions and related to population ... Megavoltage radiation therapy units in South Africa. Photon. Electron. Machine energy beam. Tvl .... Remote afrerloading brachytherapy devices have developed ...
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Results of Radiation Therapy for Squamous Cell Carcinoma of the Esophagus
International Nuclear Information System (INIS)
Chun, Ha Chung; Lee, Myung Za
2009-01-01
This study was designed to evaluate the effectiveness and prognostic factors for patients treated with postoperative radiation therapy following surgery or with radiation therapy alone for squamous cell carcinoma of the esophagus. We retrospectively analyzed 132 esophageal cancer patients treated with postoperative radiation therapy following surgery or patients who were treated with radiation therapy alone at our institution from 1989 to 2006. Thirty-five patients had stage II disease, 88 patients had stage III disease and nine patients had stage IV disease. Tumors were located at the upper esophagus in 18 patients, the mid esophagus in 81 patients and the distal esophagus in 33 patients. Sixty patients were treated with radiation therapy alone and 72 patients were treated with postoperative radiation therapy following surgery. Eight patients received a dose less than 40 Gy and 78 patients received a dose of 40 to 50 Gy. The remaining 46 patients received a dose of 50 to 60 Gy. The majority of patients who underwent postoperative radiation therapy received a dose of 45 Gy. Actuarial survival rates for all of the patients at two years and five years were 24% and 5%, respectively. The median survival time was 11 months. Survival rates for patients who underwent postoperative RT at two years and five years were 29% and 8%, respectively. The corresponding survival rates for patients who received radiation alone were 18% and 2%, respectively. Survival rates at two years and five years were 43% and 15% for stage II disease, 22% and 2% for stage III disease and 0% and 0% for stage IV disease, respectively; these findings were statistically significant. Two-year survival rates for patients with upper, middle and distal esophageal cancer were 19, 29% and 22%, respectively. Although there was a trend of slightly better survival for middle esophageal tumors, this finding was not statistically significant. Complete response to radiation was achieved in 13 patients (22%) and
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Trial Watch: Immunotherapy plus radiation therapy for oncological indications.
Vacchelli, Erika; Bloy, Norma; Aranda, Fernando; Buqué, Aitziber; Cremer, Isabelle; Demaria, Sandra; Eggermont, Alexander; Formenti, Silvia Chiara; Fridman, Wolf Hervé; Fucikova, Jitka; Galon, Jérôme; Spisek, Radek; Tartour, Eric; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo
2016-01-01
Malignant cells succumbing to some forms of radiation therapy are particularly immunogenic and hence can initiate a therapeutically relevant adaptive immune response. This reflects the intrinsic antigenicity of malignant cells (which often synthesize a high number of potentially reactive neo-antigens) coupled with the ability of radiation therapy to boost the adjuvanticity of cell death as it stimulates the release of endogenous adjuvants from dying cells. Thus, radiation therapy has been intensively investigated for its capacity to improve the therapeutic profile of several anticancer immunotherapies, including (but not limited to) checkpoint blockers, anticancer vaccines, oncolytic viruses, Toll-like receptor (TLR) agonists, cytokines, and several small molecules with immunostimulatory effects. Here, we summarize recent preclinical and clinical advances in this field of investigation.
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Reversible brachial plexopathy following primary radiation therapy for breast cancer
International Nuclear Information System (INIS)
Salner, A.L.; Botnick, L.E.; Herzog, A.G.; Goldstein, M.A.; Harris, J.R.; Levene, M.B.; Hellman, S.
1981-01-01
Reversible brachial plexopathy has occurred in very low incidence in patients with breast carcinoma treated definitively with radiation therapy. Of 565 patients treated between January 1968 and December 1979 with moderate doses of supervoltage radiation therapy (average axillary dose of 5000 rad in 5 weeks), eight patients (1.4%) developed the characteristic symptoms at a median time of 4.5 months after radiation therapy. This syndrome consists of paresthesias in all patients, with weakness and pain less commonly seen. The symptom complex differs from other previously described brachial plexus syndromes, including paralytic brachial neuritis, radiation-induced injury, and carcinoma. A possible relationship to adjuvant chemotherapy exists, though the etiology is not well-understood. The cases described demonstrate temporal clustering. Resolution is always seen
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Imaging and Data Acquisition in Clinical Trials for Radiation Therapy
Energy Technology Data Exchange (ETDEWEB)
FitzGerald, Thomas J., E-mail: Thomas.Fitzgerald@umassmed.edu [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Memorial Medical Center, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Bishop-Jodoin, Maryann [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Followill, David S. [Imaging and Radiation Oncology Core Houston, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Galvin, James [Imaging and Radiation Oncology Core Philadelphia, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Knopp, Michael V. [Imaging and Radiation Oncology Core Ohio, Wexner Medical Center, Ohio State University, Columbus, Ohio (United States); Michalski, Jeff M. [Imaging and Radiation Oncology Core St. Louis, Washington University School of Medicine, St. Louis, Missouri (United States); Rosen, Mark A. [Imaging and Radiation Oncology Core Philadelphia, University of Pennsylvania Health System, Philadelphia, Pennsylvania (United States); Bradley, Jeffrey D. [Washington University School of Medicine–Radiation Oncology, St. Louis, Missouri (United States); Shankar, Lalitha K. [National Cancer Institute, Clinical Radiation Oncology Branch, Rockville, Maryland (United States); Laurie, Fran [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Cicchetti, M. Giulia; Moni, Janaki [Imaging and Radiation Oncology Core Rhode Island, University of Massachusetts Memorial Medical Center, University of Massachusetts Medical School, Worcester, Massachusetts (United States); Coleman, C. Norman; Deye, James A.; Capala, Jacek; Vikram, Bhadrasain [National Cancer Institute, Clinical Radiation Oncology Branch, Rockville, Maryland (United States)
2016-02-01
Cancer treatment evolves through oncology clinical trials. Cancer trials are multimodal and complex. Assuring high-quality data are available to answer not only study objectives but also questions not anticipated at study initiation is the role of quality assurance. The National Cancer Institute reorganized its cancer clinical trials program in 2014. The National Clinical Trials Network (NCTN) was formed and within it was established a Diagnostic Imaging and Radiation Therapy Quality Assurance Organization. This organization is Imaging and Radiation Oncology Core, the Imaging and Radiation Oncology Core Group, consisting of 6 quality assurance centers that provide imaging and radiation therapy quality assurance for the NCTN. Sophisticated imaging is used for cancer diagnosis, treatment, and management as well as for image-driven technologies to plan and execute radiation treatment. Integration of imaging and radiation oncology data acquisition, review, management, and archive strategies are essential for trial compliance and future research. Lessons learned from previous trials are and provide evidence to support diagnostic imaging and radiation therapy data acquisition in NCTN trials.
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Imaging and Data Acquisition in Clinical Trials for Radiation Therapy
International Nuclear Information System (INIS)
FitzGerald, Thomas J.; Bishop-Jodoin, Maryann; Followill, David S.; Galvin, James; Knopp, Michael V.; Michalski, Jeff M.; Rosen, Mark A.; Bradley, Jeffrey D.; Shankar, Lalitha K.; Laurie, Fran; Cicchetti, M. Giulia; Moni, Janaki; Coleman, C. Norman; Deye, James A.; Capala, Jacek; Vikram, Bhadrasain
2016-01-01
Cancer treatment evolves through oncology clinical trials. Cancer trials are multimodal and complex. Assuring high-quality data are available to answer not only study objectives but also questions not anticipated at study initiation is the role of quality assurance. The National Cancer Institute reorganized its cancer clinical trials program in 2014. The National Clinical Trials Network (NCTN) was formed and within it was established a Diagnostic Imaging and Radiation Therapy Quality Assurance Organization. This organization is Imaging and Radiation Oncology Core, the Imaging and Radiation Oncology Core Group, consisting of 6 quality assurance centers that provide imaging and radiation therapy quality assurance for the NCTN. Sophisticated imaging is used for cancer diagnosis, treatment, and management as well as for image-driven technologies to plan and execute radiation treatment. Integration of imaging and radiation oncology data acquisition, review, management, and archive strategies are essential for trial compliance and future research. Lessons learned from previous trials are and provide evidence to support diagnostic imaging and radiation therapy data acquisition in NCTN trials.
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Factors influencing radiation therapy student clinical placement satisfaction
Bridge, Pete; Carmichael, Mary-Ann
2014-01-01
Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clinical placement. Methods: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanisms during clinical placements in a semester. Results: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. Conclusions: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning. PMID:26229635
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Factors influencing radiation therapy student clinical placement satisfaction
Energy Technology Data Exchange (ETDEWEB)
Bridge, Pete; Carmichael, Mary-Ann [School of Clinical Sciences, Queensland University of Technology, Brisbane (Australia)
2014-02-15
Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clinical placement. Methods: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanisms during clinical placements in a semester. Results: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. Conclusions: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning.
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Factors influencing radiation therapy student clinical placement satisfaction
International Nuclear Information System (INIS)
Bridge, Pete; Carmichael, Mary-Ann
2014-01-01
Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clinical placement. Methods: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanisms during clinical placements in a semester. Results: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. Conclusions: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning
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The effect of radiation therapy on hemophilic arthropathy
Energy Technology Data Exchange (ETDEWEB)
Kang, Jin Oh; Hong, Seong Eon; Kim, Sang Gi; Shin, Dong Oh [School of Medicine, KyungHee University, Seoul (Korea, Republic of)
2005-06-15
Repetitive bleeding into the joint space is the cause of debilitative hemophilic arthropathy. To interrupt this process, we treated the hemophilic patients suffering from repetitive joint bleeding with radiation therapy. From 1997 to 2001, a total of 41 joints from 37 hemophilic arthropathy patients were treated with radiation therapy at KyungHee University Hospital. The treated joints were 35 ankles, 3 knees and 3 elbows, respectively. The age of the patients ranged from 4 to 27 years (median age: 11 years). The radiation dose ranged from 900 cGy to 2360 cGy (median dose: 900 cGy). The fraction size was 150 cGy, 180 cGy or 200 cGy. The number of bleeding in one year before and after radiotherapy was compared. There was a tendency of frequent bleeding for the patients younger than 11 ({rho} 0.051) but there was also a tendency for more improvement in this group ({rho} 0.057). The number of joint bleedings was related with joint pain ({rho} 0.012) and joint swelling ({rho} = 0.033) but not with the Arbold-Hilgartner stage ({rho} 0.739),cartilage destruction ({rho} = 0.718) and synovial hypertrophy ({rho} = 0.079). The number of bleeding was reduced in thirty-three cases, and eight cases showed no improvement after radiation therapy. The average number of bleeding in a month was 2.52 before radiotherapy, but this was reduced to 1.4 after radiotherapy ({rho} = 0.017). Radiation therapy was effective for the hemophilia patients with repetitive joint bleeding to decrease the bleeding frequency and to prevent hemophilic arthropathy.
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The effect of radiation therapy on hemophilic arthropathy
International Nuclear Information System (INIS)
Kang, Jin Oh; Hong, Seong Eon; Kim, Sang Gi; Shin, Dong Oh
2005-01-01
Repetitive bleeding into the joint space is the cause of debilitative hemophilic arthropathy. To interrupt this process, we treated the hemophilic patients suffering from repetitive joint bleeding with radiation therapy. From 1997 to 2001, a total of 41 joints from 37 hemophilic arthropathy patients were treated with radiation therapy at KyungHee University Hospital. The treated joints were 35 ankles, 3 knees and 3 elbows, respectively. The age of the patients ranged from 4 to 27 years (median age: 11 years). The radiation dose ranged from 900 cGy to 2360 cGy (median dose: 900 cGy). The fraction size was 150 cGy, 180 cGy or 200 cGy. The number of bleeding in one year before and after radiotherapy was compared. There was a tendency of frequent bleeding for the patients younger than 11 (ρ 0.051) but there was also a tendency for more improvement in this group (ρ 0.057). The number of joint bleedings was related with joint pain (ρ 0.012) and joint swelling (ρ = 0.033) but not with the Arbold-Hilgartner stage (ρ 0.739),cartilage destruction (ρ = 0.718) and synovial hypertrophy (ρ = 0.079). The number of bleeding was reduced in thirty-three cases, and eight cases showed no improvement after radiation therapy. The average number of bleeding in a month was 2.52 before radiotherapy, but this was reduced to 1.4 after radiotherapy (ρ = 0.017). Radiation therapy was effective for the hemophilia patients with repetitive joint bleeding to decrease the bleeding frequency and to prevent hemophilic arthropathy
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Dosimetry challenges for implementing emerging technologies
Energy Technology Data Exchange (ETDEWEB)
Yin Fangfang; Oldham, Mark; Cai Jing; Wu Qiuwen, E-mail: Fangfang.yin@duke.ed [Department of Radiation Oncology Duke University Medical Center, Durham, NC 27516 (United States)
2010-11-01
During the last 10 years, radiation therapy technologies have gone through major changes, mainly related introduction of sophisticated delivery and imaging techniques to improve the target localization accuracy and dose conformity. While implementation of these emerging technologies such as image-guided SRS/SBRT, IMRT/IMAT, IGRT, 4D motion management, and special delivery technologies showed substantial clinical gains for patient care, many other factors, such as training/quality, efficiency/efficacy, and cost/effectiveness etc. remain to be challenging. This talk will address technical challenges for dosimetry verification of implementing these emerging technologies in radiation therapy.
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Refusal of curative radiation therapy and surgery among patients with cancer.
Aizer, Ayal A; Chen, Ming-Hui; Parekh, Arti; Choueiri, Toni K; Hoffman, Karen E; Kim, Simon P; Martin, Neil E; Hu, Jim C; Trinh, Quoc-Dien; Nguyen, Paul L
2014-07-15
Surgery and radiation therapy represent the only curative options for many patients with solid malignancies. However, despite the recommendations of their physicians, some patients refuse these therapies. This study characterized factors associated with refusal of surgical or radiation therapy as well as the impact of refusal of recommended therapy on patients with localized malignancies. We used the Surveillance, Epidemiology, and End Results program to identify a population-based sample of 925,127 patients who had diagnoses of 1 of 8 common malignancies for which surgery and/or radiation are believed to confer a survival benefit between 1995 and 2008. Refusal of oncologic therapy, as documented in the SEER database, was the primary outcome measure. Multivariable logistic regression was used to investigate factors associated with refusal. The impact of refusal of therapy on cancer-specific mortality was assessed with Fine and Gray's competing risks regression. In total, 2441 of 692,938 patients (0.4%) refused surgery, and 2113 of 232,189 patients (0.9%) refused radiation, despite the recommendations of their physicians. On multivariable analysis, advancing age, decreasing annual income, nonwhite race, and unmarried status were associated with refusal of surgery, whereas advancing age, decreasing annual income, Asian American race, and unmarried status were associated with refusal of radiation (PRefusal of surgery and radiation were associated with increased estimates of cancer-specific mortality for all malignancies evaluated (hazard ratio [HR], 2.80, 95% confidence interval [CI], 2.59-3.03; Prefuse curative surgical and/or radiation-based oncologic therapy, raising concern that socioeconomic factors may drive some patients to forego potentially life-saving care. Copyright © 2014 Elsevier Inc. All rights reserved.
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Heavy ion facility for radiation therapy
International Nuclear Information System (INIS)
Leemann, C.; Alonso, J.; Clark, D.; Grunder, H.; Hoyer, E.; Lou, K.; Staples, J.; Voelker, F.
1977-03-01
The accelerator requirements of particle radiation therapy are reviewed and a preliminary design of a heavy ion synchrotron for hospital installation is presented. Beam delivery systems and multi-treatment room arrangements are outlined
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Verrucous carcinoma of the cervix and vagina treated by radiation therapy
International Nuclear Information System (INIS)
Taylor, D.D.; Twiggs, L.B.; Okagaki, T.; Adcock, L.L.; Prem, K.A.; Potish, R.A.
1986-01-01
Seven cases of verrocous carcinoma of the uterine cervix (five) and vagina (two) were reviewed. Four of the five patients managed primarily with radiation therapy have survived a median of 10 years. Of the two patients managed primarily with surgery, one experienced recurrence and was then successfully treated with radiation therapy; the other died of metastatic carcinoma. No anaplastic transformation of lesions or distant metastases occurred in the patients treated with radiation therapy. Human papilloma virus was isolated in two patients
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Planning of radiation therapy for esophageal cancer
International Nuclear Information System (INIS)
Iwata, Takeo
1981-01-01
The esophageal malignant tumors occur mostly at the pulmonary esophagus, whereas such tumors also occur at the cervical and abdominal esophagus. Moreover, histologically, such malignant tumors are mostly carcinoma planocellulare and yet, there are not a few cases of adenomatous carcinoma and indifferentiated carcinoma. X-ray pictures reveal various types, such as infundibular, spiral and serrated forms, which are related to the radioactive therapuetic effects. However, the most difficult condition in radioactive therapies for the esophagus is that this organ is adjacent to important viscera at the surroundings, thus the most irradiating field covers the normal tissues. For such radiating sites, instead of the conventional simple radiation by 2 guns, a further progress was considered by trying to pursue more efficient and effective methods for radiating therapies in classfication by the generating or causing sites of carcinoma, in application of computers. (author)
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Energy Technology Data Exchange (ETDEWEB)
Rocha, N.K.S.; Filipov, D.; Soboll, D.S., E-mail: nhy_ksr@yahoo.com.br [Universidade Tecnológica Federal do Paraná (UFTPR),Curitiba (Brazil). Departamento Acadêmico de Física; Petchevist, P.C.D. [Oncoville, Curitiba, PR (Brazil)
2017-07-01
It is a retrospective study that analyzed positional fluctuations of 29 patients submitted to prostate radiotherapy, using IGRT. The minimum and maximum averages of the lateral, longitudinal and vertical displacements were calculated, obtaining a general average of the displacements that remained close to zero and one the most evident variation between the lateral and vertical axes.
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Principles of radiation therapy
International Nuclear Information System (INIS)
Richter, M.P.; Share, F.S.; Goodman, R.L.
1985-01-01
Radiation oncology now represents the integration of knowledge obtained over an 80-year period from the physics and biology laboratories and the medical clinic. Such integration is recent; until the supervoltage era following World War II, the chief developments in these three areas for the most part were realized independently. The physics and engineering laboratories have now developed a dependable family of sources of ionizing radiations that can be precisely directed at tumor volumes at various depths within the body. The biology laboratory has provided the basic scientific support underlying the intensive clinical experience and currently is suggesting ways of using ionizing radiations more effectively, such as modified fractionation schedules relating to cell cycle kinetics and the use of drugs and chemicals as modifiers of radiation response and normal tissue reaction. The radiation therapy clinic has provided the patient stratum on which the acute and chronic effects of irradiation have been assessed, and the patterns of treatment success and failure identified. The radiation therapist has shared with the surgeon and medical oncologist the responsibility for clarifying the natural history of a large number of human neoplasms, and through such clarifications, has developed more effective treatment strategies. Several examples of this include the improved results in the treatment of Hodgkin's disease, squamous cell carcinoma of the cervix, seminoma, and epithelial neoplasms of the upper aerodigestive tract
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Movie prediction of lung tumor for precise chasing radiation therapy
International Nuclear Information System (INIS)
Chhatkuli, Ritu Bhusal; Demachi, Kazuyuki; Kawai, Masaki; Sakakibara, Hiroshi; Uesaka, Mitsuru
2012-01-01
In recent years, precision for radiation therapy is a major challenge in the field of cancer treatment. When it comes to a moving organ like lungs, limiting the radiation to the target and sparing the surrounding healthy tissue is always a concern. It can induce the limit in the accuracy of area irradiated during lung cancer radiation therapy. Many methods have been introduced to compensate the motion in order to reduce the effect of radiation to healthy tissue due to respiratory motion. The motion of lung along with the tumor makes it very difficult to spare the healthy tissue during radiation therapy. The fear of this unintended damage to the neighboring tissue often limits the dose that can be applied to the tumor. The purpose of this research is the prediction of future motion images for the improvement of tumor tracking method. We predict the motion images by using principal component analysis (PCA) and multi-channel singular spectral analysis (MSSA) method. Time series x-ray images are used as training images. The motion images were successfully predicted and verified using the developed algorithm. The real time implementation of this method in future is believed to be significant for higher level of real time tumor tracking during radiation therapy. (author)
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Urothelial cancers following radiation therapy for cervical cancer
International Nuclear Information System (INIS)
Nakata, Seiji; Hasumi, Masaru; Sato, Jin; Mayuzumi, Takuji; Kumasaka, Fuminari; Shimizu, Toshihiro.
1996-01-01
Some reports have indicated that bladder cancer is induced by radiation therapy for cervical cancer. We encountered 6 cases of urothelial cancer (5 cases of bladder cancer and 1 case of ureter cancer) following radiation therapy for cervical cancer. Age at the time of diagnosis of cervical cancer ranged from 38 to 66 years, and the average was 51.2±11.0 (S.D.) years old. Age at the time of diagnosis of urothelial cancer ranged from 53 to 83 years, and the average was 67.5±10.3 years old. The interval between the diagnosis of cervical cancer and urothelial cancer ranged from 3 to 25 years, averaging 16.3 years. It is impossible to evaluate the risk of development of urothelial cancer after radiation therapy based on our data. However, it is important to make an effort to diagnose urothelial cancer at an early stage by educating patients (e.g., advising regular urine tests) after the follow-up period to cervical cancer. (author)
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Role of radiation therapy for 'juvenile' angiofibroma
Energy Technology Data Exchange (ETDEWEB)
Gudea, F.; Vega, M.; Canals, E.; Montserrat, J.M.; Valdano, J. (Univ. Autonoma de Barcelona (Spain). Hospital de la Santa Creu i Sant Pau (Spain))
1990-09-01
Juvenile nasopharyngeal angiofibroma (JNA) is a rare benign neoplasm which occurs primarily in male adolescents and is characterized by aggressive local growth. The controversy concerning appropriate treatment for patients with juvenile angiofibroma persists. Radiation therapy and survival resection have both been reported to be effective to control a high proportion of these tumours. The case reported here demonstrates a locally advanced JNA controlled by radiation therapy. (author).
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Radiation dermatitis and pneumonitis following breast conserving therapy
International Nuclear Information System (INIS)
Yoden, Eisaku; Hiratsuka, Junichi; Imajo, Yoshinari
2000-01-01
We investigated the frequency, degree and risk factors of radiation-induced dermatitis and pneumonitis in 255 patients receiving breast conserving therapy between April 1987 and April 1998. The majority of the patients underwent a wide excision or quadrantectomy with a level I, II axillary dissection, followed by radiotherapy consisting of 50 Gy/25 Fr/5 weeks to the preserved breast with a 4 MV beam by tangentially opposed portals using the half-field technique. Eleven patients received an additional 10 Gy/5 Fr of electron therapy to the tumor bed. Most of the patients developed radiation dermatitis which was limited to reddening or dry desquamation, with the exception of 14 patients with a localized moist reaction. The skin reaction was transient in all patients and improved with conservative treatments. Radiation pneumonitis appeared on chest X-rays in 30 patients, with a slight appearance in 21 and patchy appearance in 9. Three patients presented with persistent symptoms requiring medication. They were treated with steroids, resulting in complete resolution of the symptoms. A large volume of the chest wall within the irradiation field and a large area of irradiated skin were the risk factors of radiation dermatitis. The volume of irradiated lung significantly correlated with the frequency and degree of radiation pneumonitis. It was preferable that the maximum thickness of the involved lung should not exceed 3 cm. Complicated disease, adjuvant therapy and boost irradiation had no impact on the radiation dermatitis or pneumonitis. (author)
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Meningeal hemangiopericytoma treated with surgery and radiation therapy -case report-
Energy Technology Data Exchange (ETDEWEB)
Jang, Ji Young; Oh, Yoon Kyeong [College of Medicine, Chosun University, Gwangju (Korea, Republic of)
2006-06-15
Meningeal hemangiopericytoma (HPC) is an uncommon dura-based tumor and can recur not only locally but also distantly in the neural axis or extraneural sites. We report our experience of radiation therapy, one preoperative and one elective postoperative, in two patients with meningeal HPC and reviewed the role of radiation therapy. A 41-year-old man (Case 1) presented with a 3-month history of headache and right hemiparesis. The mass was nearly unresectable at the first and second operation and diagnosed as meningeal HPC. Preoperative radiation therapy was given with a total dose of 55.8 Gy/31 fractions to the large residual mass of left frontoparietal area. Follow-up computerized tomography (CT) showed marked regression of tumor after radiation therapy. The third operation was performed to remove the residual tumor at 6 months after the radiation therapy and a 2 x 2 cm sized tumor was encountered. The mass was totally removed. The serial follow-up CT showed no evidence of recurrence and he is alive without distant metastasis for 4 years and 10 months after the first operation. A 45-year-old woman (Case 2) presented with suddenly developed headache and visual impairment. Tumor mass occupying right frontal lobe was removed with the preoperative diagnosis of meningioma. It was totally removed with attached sagittal sinus and diagnosed as meningeal HPC. Elective postoperative radiation therapy was performed to reduce local recurrence with a total dose of 54 Gy/30 fractions to the involved area of right frontal lobe. She is alive for 5 years maintaining normal activity without local recurrence and distant metastasis.
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Meningeal hemangiopericytoma treated with surgery and radiation therapy -case report-
International Nuclear Information System (INIS)
Jang, Ji Young; Oh, Yoon Kyeong
2006-01-01
Meningeal hemangiopericytoma (HPC) is an uncommon dura-based tumor and can recur not only locally but also distantly in the neural axis or extraneural sites. We report our experience of radiation therapy, one preoperative and one elective postoperative, in two patients with meningeal HPC and reviewed the role of radiation therapy. A 41-year-old man (Case 1) presented with a 3-month history of headache and right hemiparesis. The mass was nearly unresectable at the first and second operation and diagnosed as meningeal HPC. Preoperative radiation therapy was given with a total dose of 55.8 Gy/31 fractions to the large residual mass of left frontoparietal area. Follow-up computerized tomography (CT) showed marked regression of tumor after radiation therapy. The third operation was performed to remove the residual tumor at 6 months after the radiation therapy and a 2 x 2 cm sized tumor was encountered. The mass was totally removed. The serial follow-up CT showed no evidence of recurrence and he is alive without distant metastasis for 4 years and 10 months after the first operation. A 45-year-old woman (Case 2) presented with suddenly developed headache and visual impairment. Tumor mass occupying right frontal lobe was removed with the preoperative diagnosis of meningioma. It was totally removed with attached sagittal sinus and diagnosed as meningeal HPC. Elective postoperative radiation therapy was performed to reduce local recurrence with a total dose of 54 Gy/30 fractions to the involved area of right frontal lobe. She is alive for 5 years maintaining normal activity without local recurrence and distant metastasis
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Curative Radiation Therapy for T2N0M0
International Nuclear Information System (INIS)
Park, In Kyu; Kim, Jae Choel
1995-01-01
Purpose : Surgery is the treatment of choice for resectable non-small cell lung cancer. For patients who are medically unable to tolerate a surgical resection or who refuse surgery, radiation therapy is an acceptable alternative. A retrospective analysis of patients with stage I non-small cell lung cancer treated with curative radiation therapy was performed to determine the results of curative radiation therapy and patterns of failure, and to identify factors that may influence survival. Materials and Methods : From 1986 through 1993, 39 patients with T2N0M0 non-small cell lung cancer were treated with curative radiation therapy at department of radiation oncology, Kyungpook national university hospital All patients were not candidates for surgical resection because of either patient refusal (16 patients), poor pulmonary function (12 patients), old age (7 patients), poor performance (2 patients) or coexisting medical disease (2 patients). Median age of patients was 67 years. Histologic cell type was squamous cell carcinoma in 1. All patients were treated with megavoltage irradiation and radiation dose raged from 5000cGy to 6150 cGy with a median dose of 600cGy. The median follow-up was 17 months with a range of 4 to 82 months. Survival was measured from the date therapy initiated. Results : The overall survival rate for entire patients was 40.6% at 2 years and 27.7% at 3 years, with a median survival time of 21 months he disease-free survival at 2 and 3 years was 51.7% and 25.8%, respectively. Of evaluable 20 Patients with complete response, 15 Patients were considered to have failed. Of these, 13 patients showed local failure and 2 patients failed distantly. Response to treatment (p=0.0001), tumor size (p=0.0019) and age p=0.0247) were favorably associated with overall survival. Only age was predictive for disease-free survival (p=0.0452). Conclusion : Radiation therapy is an effective treatment for small (less than 3 cm) tumors, and should be offered as an
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Energy Technology Data Exchange (ETDEWEB)
Ding, Xuanfeng; Dionisi, Francesco; Tang, Shikui; Ingram, Mark; Hung, Chun-Yu; Prionas, Evangelos; Lichtenwalner, Phil; Butterwick, Ian; Zhai, Huifang; Yin, Lingshu; Lin, Haibo; Kassaee, Alireza; Avery, Stephen, E-mail: stephen.avery@uphs.upenn.edu
2014-07-01
With traditional photon therapy to treat large postoperative pancreatic target volume, it often leads to poor tolerance of the therapy delivered and may contribute to interrupted treatment course. This study was performed to evaluate the potential advantage of using passive-scattering (PS) and modulated-scanning (MS) proton therapy (PT) to reduce normal tissue exposure in postoperative pancreatic cancer treatment. A total of 11 patients with postoperative pancreatic cancer who had been previously treated with PS PT in University of Pennsylvania Roberts Proton Therapy Center from 2010 to 2013 were identified. The clinical target volume (CTV) includes the pancreatic tumor bed as well as the adjacent high-risk nodal areas. Internal (iCTV) was generated from 4-dimensional (4D) computed tomography (CT), taking into account target motion from breathing cycle. Three-field and 4-field 3D conformal radiation therapy (3DCRT), 5-field intensity-modulated radiation therapy, 2-arc volumetric-modulated radiation therapy, and 2-field PS and MS PT were created on the patients’ average CT. All the plans delivered 50.4 Gy to the planning target volume (PTV). Overall, 98% of PTV was covered by 95% of the prescription dose and 99% of iCTV received 98% prescription dose. The results show that all the proton plans offer significant lower doses to the left kidney (mean and V{sub 18} {sub Gy}), stomach (mean and V{sub 20} {sub Gy}), and cord (maximum dose) compared with all the photon plans, except 3-field 3DCRT in cord maximum dose. In addition, MS PT also provides lower doses to the right kidney (mean and V{sub 18} {sub Gy}), liver (mean dose), total bowel (V{sub 20} {sub Gy} and mean dose), and small bowel (V{sub 15} {sub Gy} absolute volume ratio) compared with all the photon plans and PS PT. The dosimetric advantage of PT points to the possibility of treating tumor bed and comprehensive nodal areas while providing a more tolerable treatment course that could be used for dose
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International Nuclear Information System (INIS)
Ding, Xuanfeng; Dionisi, Francesco; Tang, Shikui; Ingram, Mark; Hung, Chun-Yu; Prionas, Evangelos; Lichtenwalner, Phil; Butterwick, Ian; Zhai, Huifang; Yin, Lingshu; Lin, Haibo; Kassaee, Alireza; Avery, Stephen
2014-01-01
With traditional photon therapy to treat large postoperative pancreatic target volume, it often leads to poor tolerance of the therapy delivered and may contribute to interrupted treatment course. This study was performed to evaluate the potential advantage of using passive-scattering (PS) and modulated-scanning (MS) proton therapy (PT) to reduce normal tissue exposure in postoperative pancreatic cancer treatment. A total of 11 patients with postoperative pancreatic cancer who had been previously treated with PS PT in University of Pennsylvania Roberts Proton Therapy Center from 2010 to 2013 were identified. The clinical target volume (CTV) includes the pancreatic tumor bed as well as the adjacent high-risk nodal areas. Internal (iCTV) was generated from 4-dimensional (4D) computed tomography (CT), taking into account target motion from breathing cycle. Three-field and 4-field 3D conformal radiation therapy (3DCRT), 5-field intensity-modulated radiation therapy, 2-arc volumetric-modulated radiation therapy, and 2-field PS and MS PT were created on the patients’ average CT. All the plans delivered 50.4 Gy to the planning target volume (PTV). Overall, 98% of PTV was covered by 95% of the prescription dose and 99% of iCTV received 98% prescription dose. The results show that all the proton plans offer significant lower doses to the left kidney (mean and V 18 Gy ), stomach (mean and V 20 Gy ), and cord (maximum dose) compared with all the photon plans, except 3-field 3DCRT in cord maximum dose. In addition, MS PT also provides lower doses to the right kidney (mean and V 18 Gy ), liver (mean dose), total bowel (V 20 Gy and mean dose), and small bowel (V 15 Gy absolute volume ratio) compared with all the photon plans and PS PT. The dosimetric advantage of PT points to the possibility of treating tumor bed and comprehensive nodal areas while providing a more tolerable treatment course that could be used for dose escalation and combining with radiosensitizing
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Energy Technology Data Exchange (ETDEWEB)
Park, Jong Min [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Advanced Institutes of Convergence Technology, Robotics Research Laboratory for Extreme Environments, Suwon (Korea, Republic of); Shin, Kyung Hwan; Wu, Hong-Gyun [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of); Kim, Jung-in; Park, So-Yeon; Kim, Jin Ho [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Seoul National University Hospital, Biomedical Research Institute, Seoul (Korea, Republic of); Seoul National University Medical Research Center, Institute of Radiation Medicine, Seoul (Korea, Republic of); Jeon, Seung Hyuck [Seoul National University Hospital, Department of Radiation Oncology, Seoul (Korea, Republic of); Choi, Noorie [Seoul National University College of Medicine, Department of Radiation Oncology, Seoul (Korea, Republic of)
2018-01-15
To investigate and to prevent irradiation outside the treatment field caused by an electron stream in the air generated by the magnetic field during magnetic resonance image-guided accelerated partial breast irradiation (APBI). In all, 20 patients who received APBI with a magnetic resonance image-guided radiation therapy (MR-IGRT) system were prospectively studied. The prescription dose was 38.5 Gy in 10 fractions of 3.85 Gy and delivered with a tri-cobalt system (the ViewRay system). For each patient, primary plans were delivered for the first five fractions and modified plans with different gantry angles from those of the primary plan (in-treatment plans) were delivered for the remaining five fractions to reduce the skin dose. A 1 cm thick bolus was placed in front of the patient's jaw, ipsilateral shoulder, and arm to shield them from the electron stream. Radiochromic EBT3 films were attached to the front (towards the breast) and back (towards the head) of the bolus during treatment. Correlations between the measured values and the tumor locations, treatment times, and tumor sizes were investigated. For a single fraction delivery, the average areas of the measured isodoses of 14% (0.54 Gy), 12% (0.46 Gy), and 10% (0.39 Gy) at the front of the boluses were as large as 3, 10.4, and 21.4 cm{sup 2}, respectively, whereas no significant dose could be measured at the back of the boluses. Statistically significant but weak correlations were observed between the measured values and the treatment times. During radiotherapy for breast cancer with an MR-IGRT system, the patient must be shielded from electron streams in the air generated by the interaction of the magnetic field with the beams of the three-cobalt treatment unit to avoid unwanted irradiation of the skin outside the treatment field. (orig.) [German] Beim Einsatz eines Magnetresonanztomographie(MRT)-gefuehrten Bestrahlungsgeraets kann durch die Wechselwirkung von Magnetfeld und Strahlenquelle unerwuenscht
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In vivo dosimetry in radiation therapy in Sweden
International Nuclear Information System (INIS)
Eriksson, Jacob; Blomquist, Michael
2010-07-01
A prerequisite for achieving high radiation safety for patients receiving external beam radiation therapy is that the hospitals have a quality assurance program. The program should include include monitoring of the radiation dose given to the patient. Control measurements are performed both at the system level and at the individual level. Control measurement is normally performed using in vivo dosimetry, e.g. a method to measure the radiation dose at the individual level during the actual radiation treatment time. In vivo dosimetry has proven to be an important tool to detect and prevent serious errors in patient treatment. The purpose of this research project was to identify the extent to which vivo dosimetry is used and the methods available for this at Swedish radiation therapy clinics. The authority also wanted to get an overall picture of how hospitals manage results of in vivo dosimetry, and how clinics control radiation dose when using modern treatment techniques. The report reflects the situation in Swedish radiotherapy clinics 2007. The report shows that all hospitals use some form of in vivo dosimetry. The instruments used are mainly diodes and termoluminiscence dosimeters
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Source book of educational materials for radiation therapy. Final report
International Nuclear Information System (INIS)
Pijar, M.L.
1979-08-01
The Source Book is a listing of educational materials in radiation therapy technology. The first 17 sections correspond to the subjects identified in the ASRT Curriculum Guide for schools of radiation therapy. Each section is divided into publications and in some sections audiovisuals and training aids. Entries are listed without endorsement
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International Nuclear Information System (INIS)
Nozaki, Miwako
2003-01-01
Radiation therapy has been playing important roles in the treatment of childhood acute leukemia since the 1970s. The first is the preventive cranial irradiation for central nervous system therapy in acute lymphoblastic leukemia. The second is the total body irradiation as conditioning before bone marrow transplantation for children with acute myeloid leukemia in first remission and with acute lymphoblastic leukemia in second remission. Although some late effects have been reported, a part of them could be overcome by technical improvement in radiation and salvage therapy. Radiation therapy for children might have a successful outcome on a delicate balance between efficiencies and potential late toxicities. The role of radiation therapy for childhood acute leukemia was reviewed from the standpoint of basic and clinical radiation oncology in this paper. (author)
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Dose distribution following selective internal radiation therapy
International Nuclear Information System (INIS)
Fox, R.A.; Klemp, P.F.; Egan, G.; Mina, L.L.; Burton, M.A.; Gray, B.N.
1991-01-01
Selective Internal Radiation Therapy is the intrahepatic arterial injection of microspheres labelled with 90Y. The microspheres lodge in the precapillary circulation of tumor resulting in internal radiation therapy. The activity of the 90Y injected is managed by successive administrations of labelled microspheres and after each injection probing the liver with a calibrated beta probe to assess the dose to the superficial layers of normal tissue. Predicted doses of 75 Gy have been delivered without subsequent evidence of radiation damage to normal cells. This contrasts with the complications resulting from doses in excess of 30 Gy delivered from external beam radiotherapy. Detailed analysis of microsphere distribution in a cubic centimeter of normal liver and the calculation of dose to a 3-dimensional fine grid has shown that the radiation distribution created by the finite size and distribution of the microspheres results in an highly heterogeneous dose pattern. It has been shown that a third of normal liver will receive less than 33.7% of the dose predicted by assuming an homogeneous distribution of 90Y
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Radiation-induced pseudotumor following therapy for soft tissue sarcoma
Energy Technology Data Exchange (ETDEWEB)
Moore, Lacey F.; Kransdorf, Mark J. [Mayo Clinic, Department of Radiology, Jacksonville, FL (United States); Buskirk, Steven J. [Mayo Clinic, Department of Radiation Oncology, Jacksonville, FL (United States); O' Connor, Mary I. [Mayo Clinic, Department of Orthopedic Surgery, Jacksonville, FL (United States); Menke, David M. [Mayo Clinic, Department of Pathology, Jacksonville, FL (United States)
2009-06-15
The purpose of this study was to describe the prevalence and imaging appearance of radiation induced pseudotumors in patients following radiation therapy for extremity soft tissue sarcomas. We retrospectively reviewed the serial magnetic resonance (MR) images of 24 patients following radiation therapy for extremity soft tissue sarcomas. A total of 208 exams were reviewed (mean, 8.7 exams per patient) and included all available studies following the start of radiation therapy. Exams were analyzed for the identification of focal signal abnormalities within the surgical bed suggesting local tumor recurrence. Histopathologic correlation was available in nine patients suspected of having local tumor recurrence. Additional information recorded included patient demographics, tumor type and location, radiation type, and dose. The study group consisted of 12 men and 12 women, having an average age of 63 years (range, 39-88 years). Primary tumors were malignant fibrous histiocytoma (n = 13), leiomyosarcoma (n = 6), liposarcoma (n = 3), synovial sarcoma (n = 1), and extraskeletal chondrosarcoma (n = 1). All lesions were high-grade sarcomas, except for two myxoid liposarcomas. Average patient radiation dose was 5,658 cGy (range, 4,500-8,040 cGy). Average follow-up time was 63 months (range, 3-204 months). Focal signal abnormalities suggesting local recurrence were seen in nine (38%) patients. Three of the nine patients with these signal abnormalities were surgically proven to have radiation-induced pseudotumor. The pseudotumors developed between 11 and 61 months following the initiation of radiation therapy (mean, 38 months), with an average radiation dose of 5,527 cGy (range, 5,040-6,500 cGy). MR imaging demonstrated a relatively ill-defined ovoid focus of abnormal signal and intense heterogeneous enhancement with little or no associated mass effect. MR imaging of radiation-induced pseudotumor typically demonstrates a relatively ill-defined ovoid mass-like focus of intense
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Refusal of Curative Radiation Therapy and Surgery Among Patients With Cancer
International Nuclear Information System (INIS)
Aizer, Ayal A.; Chen, Ming-Hui; Parekh, Arti; Choueiri, Toni K.; Hoffman, Karen E.; Kim, Simon P.; Martin, Neil E.; Hu, Jim C.; Trinh, Quoc-Dien; Nguyen, Paul L.
2014-01-01
Purpose: Surgery and radiation therapy represent the only curative options for many patients with solid malignancies. However, despite the recommendations of their physicians, some patients refuse these therapies. This study characterized factors associated with refusal of surgical or radiation therapy as well as the impact of refusal of recommended therapy on patients with localized malignancies. Methods and Materials: We used the Surveillance, Epidemiology, and End Results program to identify a population-based sample of 925,127 patients who had diagnoses of 1 of 8 common malignancies for which surgery and/or radiation are believed to confer a survival benefit between 1995 and 2008. Refusal of oncologic therapy, as documented in the SEER database, was the primary outcome measure. Multivariable logistic regression was used to investigate factors associated with refusal. The impact of refusal of therapy on cancer-specific mortality was assessed with Fine and Gray's competing risks regression. Results: In total, 2441 of 692,938 patients (0.4%) refused surgery, and 2113 of 232,189 patients (0.9%) refused radiation, despite the recommendations of their physicians. On multivariable analysis, advancing age, decreasing annual income, nonwhite race, and unmarried status were associated with refusal of surgery, whereas advancing age, decreasing annual income, Asian American race, and unmarried status were associated with refusal of radiation (P<.001 in all cases). Refusal of surgery and radiation were associated with increased estimates of cancer-specific mortality for all malignancies evaluated (hazard ratio [HR], 2.80, 95% confidence interval [CI], 2.59-3.03; P<.001 and HR 1.97 [95% CI, 1.78-2.18]; P<.001, respectively). Conclusions: Nonwhite, less affluent, and unmarried patients are more likely to refuse curative surgical and/or radiation-based oncologic therapy, raising concern that socioeconomic factors may drive some patients to forego potentially life
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Refusal of Curative Radiation Therapy and Surgery Among Patients With Cancer
Energy Technology Data Exchange (ETDEWEB)
Aizer, Ayal A., E-mail: aaaizer@partners.org [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Chen, Ming-Hui [Department of Statistics, University of Connecticut, Storrs, Connecticut (United States); Parekh, Arti [Boston University School of Medicine, Boston, Massachusetts (United States); Choueiri, Toni K. [Lank Center for Genitourinary Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Harvard Medical School, Boston, Massachusetts (United States); Hoffman, Karen E. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kim, Simon P. [Department of Urology, Mayo Clinic, Rochester, Minnesota (United States); Martin, Neil E. [Lank Center for Genitourinary Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Harvard Medical School, Boston, Massachusetts (United States); Hu, Jim C. [Department of Urology, University of California, Los Angeles, California (United States); Trinh, Quoc-Dien [Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Center, Montreal, Quebec (Canada); Nguyen, Paul L. [Lank Center for Genitourinary Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Harvard Medical School, Boston, Massachusetts (United States)
2014-07-15
Purpose: Surgery and radiation therapy represent the only curative options for many patients with solid malignancies. However, despite the recommendations of their physicians, some patients refuse these therapies. This study characterized factors associated with refusal of surgical or radiation therapy as well as the impact of refusal of recommended therapy on patients with localized malignancies. Methods and Materials: We used the Surveillance, Epidemiology, and End Results program to identify a population-based sample of 925,127 patients who had diagnoses of 1 of 8 common malignancies for which surgery and/or radiation are believed to confer a survival benefit between 1995 and 2008. Refusal of oncologic therapy, as documented in the SEER database, was the primary outcome measure. Multivariable logistic regression was used to investigate factors associated with refusal. The impact of refusal of therapy on cancer-specific mortality was assessed with Fine and Gray's competing risks regression. Results: In total, 2441 of 692,938 patients (0.4%) refused surgery, and 2113 of 232,189 patients (0.9%) refused radiation, despite the recommendations of their physicians. On multivariable analysis, advancing age, decreasing annual income, nonwhite race, and unmarried status were associated with refusal of surgery, whereas advancing age, decreasing annual income, Asian American race, and unmarried status were associated with refusal of radiation (P<.001 in all cases). Refusal of surgery and radiation were associated with increased estimates of cancer-specific mortality for all malignancies evaluated (hazard ratio [HR], 2.80, 95% confidence interval [CI], 2.59-3.03; P<.001 and HR 1.97 [95% CI, 1.78-2.18]; P<.001, respectively). Conclusions: Nonwhite, less affluent, and unmarried patients are more likely to refuse curative surgical and/or radiation-based oncologic therapy, raising concern that socioeconomic factors may drive some patients to forego potentially life
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Image Guidance and Assessment of Radiation Induced Gene Therapy
National Research Council Canada - National Science Library
Pelizzari, Charles
2004-01-01
Image guidance and assessment techniques are being developed for combined radiation/gene therapy, which utilizes a radiation-inducible gene promoter to cause expression of tumor necrosis factor alpha...
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Evaluation on the Radiation Exposure of Radiation Workers in Proton Therapy
International Nuclear Information System (INIS)
Lee, Seung Hyun; Jang, Yo Jong; Kim, Tae Yoon; Jeong, Do Hyung; Choi, Gye Suk
2012-01-01
Unlike the existing linear accelerator with photon, proton therapy produces a number of second radiation due to the kinds of nuclide including neutron that is produced from the interaction with matter, and more attention must be paid on the exposure level of radiation workers for this reason. Therefore, thermoluminescence dosimeter (TLD) that is being widely used to measure radiation was utilized to analyze the exposure level of the radiation workers and propose a basic data about the radiation exposure level during the proton therapy. The subjects were radiation workers who worked at the proton therapy center of National Cancer Center and TLD Badge was used to compare the measured data of exposure level. In order to check the dispersion of exposure dose on body parts from the second radiation coming out surrounding the beam line of proton, TLD (width and length: 3 mm each) was attached to on the body spots (lateral canthi, neck, nipples, umbilicus, back, wrists) and retained them for 8 working hours, and the average data was obtained after measuring them for 80 hours. Moreover, in order to look into the dispersion of spatial exposure in the treatment room, TLD was attached on the snout, PPS (Patient Positioning System), Pendant, block closet, DIPS (Digital Image Positioning System), Console, doors and measured its exposure dose level during the working hours per day. As a result of measuring exposure level of TLD Badge of radiation workers, quarterly average was 0.174 mSv, yearly average was 0.543 mSv, and after measuring the exposure level of body spots, it showed that the highest exposed body spot was neck and the lowest exposed body spot was back (the middle point of a line connecting both scapula superior angles). Investigation into the spatial exposure according to the workers' movement revealed that the exposure level was highest near the snout and as the distance becomes distant, it went lower. Even a small amount of exposure will eventually increase
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Waiting Lists for Radiation Therapy: A Case Study
Directory of Open Access Journals (Sweden)
Singer Peter A
2001-04-01
Full Text Available Abstract Background Why waiting lists arise and how to address them remains unclear, and an improved understanding of these waiting list "dynamics" could lead to better management. The purpose of this study is to understand how the current shortage in radiation therapy in Ontario developed; the implications of prolonged waits; who is held accountable for managing such delays; and short, intermediate, and long-term solutions. Methods A case study of the radiation therapy shortage in 1998-99 at Princess Margaret Hospital, Toronto, Ontario, Canada. Relevant documents were collected; semi-structured, face-to-face interviews with ten administrators, health care workers, and patients were conducted, audio-taped and transcribed; and relevant meetings were observed. Results The radiation therapy shortage arose from a complex interplay of factors including: rising cancer incidence rates; broadening indications for radiation therapy; human resources management issues; government funding decisions; and responsiveness to previous planning recommendations. Implications of delays include poorer cancer control rates; patient suffering; and strained doctor-patient relationships. An incompatible relationship exists between moral responsibility, borne by government, and legal liability, borne by physicians. Short-term solutions include re-referral to centers with available resources; long-term solutions include training and recruiting health care workers, improving workload standards, increasing compensation, and making changes to the funding formula. Conclusion Human resource planning plays a critical role in the causes and solutions of waiting lists. Waiting lists have harsh implications for patients. Accountability relationships require realignment.
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Adjuvant radiation therapy versus surgery alone in operable breast cancer
International Nuclear Information System (INIS)
Rutqvist, L.E.; Pettersson, D.; Johansson, H.
1993-01-01
This paper presents long-term results from a randomized trial of pre- or postoperative megavoltage radiation therapy versus surgery alone in pre- and postmenopausal women with operable breast cancer. Treatment outcome after relapse among patients who developed loco-regional recurrences was also analyzed. A total of 960 patients were included in the trial. The mean follow-up was 16 years (range: 13-19 years). The radiation therapy was individually planned. It included the chest wall (and the breast in the preoperative cases) and the regional lymph nodes. The tumor dose was 45 Gy/5 weeks. No adjuvant systemic therapy was used. The results showed a significant benefit with radiation therapy in terms of recurrence-free survival during the entire follow-up period. There was also an overall survival difference - corresponding to 16% reduction of deaths - in favour of the irradiated patients which, however, was not statistically significant (p=0.09). Among those 169 patients who developed loco-regional recurrences long-term control was only achieved in about one-third of the cases. This figure was similar among those who had received adjuvant radiation therapy (34%) compared to those initially treated with surgery alone (32%). This implied that the overall proportion of patients who eventually developed uncontrolled local disease was significantly higher among those initially allocated to surgery alone (16%) compared to those allocated to pre- or postoperative radiation therapy (6%, p<0.01). These results suggest that local undertreatment may be deleterious in subgroups of patients. (author) 5 tabs
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Energy Technology Data Exchange (ETDEWEB)
Sorcini, B.; Tilikidis, A. [Karolinska Univ. Hospital, Dept. of Medical Physics, Stockholm (Sweden)
2006-09-15
Image-guided radiation therapy (IGRT) can be used to measure and correct positional errors for target and critical structures immediately prior to or during treatment delivery. Some of the most recent available methods applied for target localization are: trans-abdominal ultrasound, implanted markers with in room MV or kV X-rays, optical surface tracking systems, implantable electromagnetic markers, in room CT such as kVCT on rail, kilo-voltage or mega-voltage cone-beam CT (CBCT) and helical megavoltage CT. The verification of the accurate treatment position in conjunction with detailed anatomical information before every fraction can be essential for the outcome of the treatment. In this paper we present the on-board imager (OBI, Varian Medical Systems, Palo Alto, CA) that has been in routine clinical use at the Karolinska University Hospital since June 2004. The OBI has been used for on-line set-up correction of prostate patients using internal gold markers. Displacements of these markers can be monitored radiographically during the treatment course and the registered marker shifts act as a surrogate for prostate motion. For this purpose, on-board kV-kV seems to be an ideal system in terms of image quality. The CBCT function of OBI was installed in March 2005 at our department. It focuses on localizing tumors based on internal anatomy, not just on the conventional external marks or tattoos. The CBCT system provides the capacity for soft tissue imaging in the treatment position and real-time radiographic monitoring during treatment delivery. (authors)
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International Nuclear Information System (INIS)
Markiewicz, Deborah A.; Schultz, Delray J.; Haas, Jonathan A.; Harris, Eleanor E. R.; Fox, Kevin R.; Glick, John H.; Solin, Lawrence J.
1996-01-01
Purpose: Chemotherapy plays an increasingly important role in the treatment of both node-negative and node-positive breast cancer patients, but the optimal sequencing of chemotherapy and radiation therapy is not well established. The purpose of this study is to evaluate the interaction of sequence and type of chemotherapy and hormonal therapy given with radiation therapy on the cosmetic outcome and the incidence of complications of Stage I and II breast cancer patients treated with breast-conserving therapy. Methods and Materials: The records of 1053 Stage I and II breast cancer patients treated with curative intent with breast-conserving surgery, axillary dissection, and radiation therapy between 1977-1991 were reviewed. Median follow-up after treatment was 6.7 years. Two hundred fourteen patients received chemotherapy alone, 141 patients received hormonal therapy alone, 86 patients received both, and 612 patients received no adjuvant therapy. Patients who received chemotherapy ± hormonal therapy were grouped according to sequence of chemotherapy: (a) concurrent = concurrent chemotherapy with radiation therapy followed by chemotherapy; (b) sequential = radiation followed by chemotherapy or chemotherapy followed by radiation; and (c) sandwich = chemotherapy followed by concurrent chemotherapy and radiation followed by chemotherapy. Compared to node negative patients, node-positive patients more commonly received chemotherapy (77 vs. 9%, p < 0.0001) and/or hormonal therapy (40 vs. 14%, p < 0.0001). Among patients who received chemotherapy, the majority (243 patients) received concurrent chemotherapy and radiation therapy with two cycles of cytoxan and 5-fluorouracil (5-FU) administered during radiation followed by six cycles of chemotherapy with cytoxan, 5-fluorouracil and either methotrexate(CMF) or doxorubicin(CAF). For analysis of cosmesis, patients included were relapse free with 3 years minimum follow-up. Results: The use of chemotherapy had an adverse effect
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Craniopharyngioma: treatment by conservative surgery and radiation therapy.
Directory of Open Access Journals (Sweden)
Nagpal R
1992-10-01
Full Text Available Benign neoplasms are curable only when excised. This applies even to craniopharyngiomas. The proximity of craniopharyngiomas to the hypothalamus and neurovascular structures makes total excision difficult to achieve. Over the last 3-4 decades, it has become increasingly obvious that craniopharyngiomas respond to radiation therapy. Early, unhappy results with major excisions have prompted us to adopt a policy of conservative surgery and radiation therapy to the residual tumour. Preliminary results suggest a good outcome in 35 of the 63 patients so treated from 1981. Details of the study are presented.
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Effectiveness of Cepharanthin in decreasing interruptions during radiation therapy for oral cancer
International Nuclear Information System (INIS)
Uchiyama, Yuka; Murakami, Shumei; Kamimoto, Naoya; Nakatani, Atsutoshi; Furukawa, Souhei
2005-01-01
The objectives of this study was to examine the effectiveness of Cepharanthin (Kakensyoyaku, Tokyo, Japan) at decreasing side effects during radiation therapy for oral cancer and thereby allowing the completion of radiation therapy without interruption. Two hundred fifteen patients diagnosed with oral cancers were assigned to either Cepharanthin or control groups and underwent external beam irradiation. The completion of the course of radiation therapy and the occurrence of side effects such as mucositis, dysgeusia, and xerostomia during the radiation therapy were evaluated and compared. The completion rate was 87.4% for the Cepharanthin group versus 67.0% for the control group, and the difference was statistically significant (P<0.01). Mucositis did not appear in 58 of 127 cases (45.7%) in the Cepharanthin group or in 21 of 88 cases (23.9%) in the control group. Mucositis developed in 24.6% of the Cepharanthin group and 53.7% of the control group within 2 weeks of irradiation. There were significant relationships between the use of Cepharanthin and the development and timing of mucositis (both P<0.01). Cepharanthin improved the completion of radiation therapy without interruption and reduced or delayed the development of mucositis during radiation therapy for oral cancer. (author)
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Quality assurance for 3D conformal radiation therapy
International Nuclear Information System (INIS)
Purdy, J.A.; Harms, W.B.
1998-01-01
Three-dimensional conformal radiation therapy (3D CRT) can be considered as an integrated process of treatment planning, delivery, and verification that attempts to conform the prescription dose closely to the target volume while limiting dose to critical normal structures. Requiring the prescription dose to conform as closely as possible to the target volume raises the level of the precision and accuracy requirements generally found in conventional radiation therapy. 3D CRT treatment planning requires robust patient immobilization/repositioning systems and volumetric image data (CT and/or MR) acquired in the treatment position. 3D treatment planning more explicitly details the particular of a patient's treatment than was ever possible with 2D treatment planning. In 1992, we implemented a formal 3D treatment planning service in our clinic and at the same time instituted a formal quality assurance (QA) program addressing the individual procedures that make up the 3D CRT process. Our 3D QA program includes systematic testing of the hardware and software used in the 3D treatment planning process, careful review of each patient's treatment plan, careful review of the physical implementation of the treatment plan, a peer review 3D QA Case Conference, and a formal continuing education program in 3D CRT for our radiation therapy staff. This broad 3D QA program requires the involvement of physicians, physicists, dosimetrists, and the treating radiation therapists that complete the team responsible for 3D CRT.3D CRT capabilities change the kinds of radiation therapy treatments that are possible and that changes the process with which treatment planning and treatment delivery are performed. There is no question that 3D CRT shows significant potential for improving the quality of radiation therapy and improving the efficiency with which it can be delivered. However, its implementation and wide spread use is still in its initial stages. The techniques used for 3D treatment
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Intensity-Modulated Radiation Therapy for Primary Brain Tumors
Institute of Scientific and Technical Information of China (English)
Zhong-min Wang
2004-01-01
Radiation therapy has been used to treat primary brain tumors as standard primary and/or adjunctive therapies for decades. It is difficult for conventional radiotherapy to deliver a lethal dose of radiation to the tumors while sparing surrounding normal brain due to complicated structures and multifunction in human brain. With the understanding of radiation physics and computer technology, a number of novel and more precise radiotherapies have been developed in recent years. Intensity modulated radiotherapy (IMRT) is one of these strategies. The use of IMRT in the treatment of primary brain tumors is being increasing nowadays. It shows great promise for some of primary brain tumors and also presents some problems, This review highlights current IMRT in the treatment of mainly primary brain tumors.
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Doses to Carotid Arteries After Modern Radiation Therapy for Hodgkin Lymphoma
DEFF Research Database (Denmark)
Maraldo, M.V.; Brodin, Nils Patrik; Aznar, Marianne Camille
2013-01-01
Hodgkin lymphoma (HL) survivors are at an increased risk of stroke because of carotid artery irradiation. However, for early-stage HL involved node radiation therapy (INRT) reduces the volume of normal tissue exposed to high doses. Here, we evaluate 3-dimensional conformal radiation therapy (3D......-CRT), volumetric-modulated arc therapy (VMAT), and proton therapy (PT) delivered as INRT along with the extensive mantle field (MF) by comparing doses to the carotid arteries and corresponding risk estimates....
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Cell cycle kinetics and radiation therapy
International Nuclear Information System (INIS)
Mendelsohn, M.L.
1975-01-01
Radiation therapy as currently practiced involves the subtle largely empirical art of balancing the recurrence of cancer due to undertreatment against severe damage to local tissues due to overtreatment. Therapeutic results too often fall short of desired success rates; yet, the therapist is continually tantalized to the likelihood that a slight shift of therapeutic ratio favoring normal tissue over cancer would have a profoundly beneficial effect. The application of cell cycle kinetics to radiation therapy is one hope for improving the therapeutic ratio; but, as I will try to show, kinetic approaches are complex, poorly understood, and presently too elusive to elicit confidence or to be used clinically. Their promise lies in their diversity and in the magnitude of our ignorance about how they work and how they should be used. Potentially useful kinetic approaches to therapy can be grouped into three classes. The first class takes advantage of intracyclic differential sensitivity, an effect involving the metabolism and biology of the cell cycle; its strategies are based on synchronization of cells over intervals of hours to days. The second class involves the distinction between cycling and noncycling cells; its strategies are based on the resistance of noncycling cells to cycle-linked radiation sensitizers and chemotherapeutic agents. The third class uses cell repopulation between fractions; its strategies are based on the relative growth rates of tumor and relevant normal tissue before and after perturbation
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The role of radiation therapy in the management of the non-Hodgkin's lymphoma
International Nuclear Information System (INIS)
Masaki, Norie
1988-01-01
Radiation therapy has its major role in the management of patients with localized non-Hodgkin's lymphoma. For patients with stage I-II malignant lymphoma with low-grade malignancy, five-year survival rates after radiation therapy are 75 - 100 %. For patients with intermediate malignancy, five-year survival rates after radiation therapy alone are 70 - 100 % for patients with pathological stage I - II and 45 - 75 % for clinical stage I - II. Radiation dose to the tumor at least 40 Gy was required to produce consistent local control. Initial use of chemotherapy with radiation therapy is indicated to improve relapse-free survival rate for patients with clinical stage I - II, as well as pathological stage I - II. (author)
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Radiation therapy and herpes zoster
International Nuclear Information System (INIS)
Kaneko, Itsuo; Matsushima, Hideno; Yamada, Teruyo; Moriya, Hiroshi
1975-01-01
The relationship between herpes zoster and radiation therapy was discussed and the combination of herpes zoster with malignancies was observed. Reported were five cases of herpes zoster (four breast and one lung carcinoma) out of 317 cases of malignancies which were irradiated in our clinic and include considerations about the etiologic relationship. (J.P.N.)
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Quality assurance study for dosimetry of Radiation Therapy equipment in Saudi Arabia
International Nuclear Information System (INIS)
Al-Mokhlef, Jazi M.; Nabaz, Noori
2003-01-01
International standards address the accuracy of dose delivery for radiation therapy machines as well as quality assurance and staffing levels for radiation therapy centers. We performed absolute calibrations of gamma ,X-ray and electron radiotherapy beams in all radiation therapy centers in Saudi Arabia. We also assessed quality assurance and staffing levels Dosimetric measurements were made with a portable dosimetry system, which consisted of a calibrated Farmer ionization chamber and an electrometer, small water phantom, barometer and thermometer. Differences between the measured and the expected output (c Gy/MU or c Gy/min) were found to be in the range of -11%+5%. About 17% of radiotherapy beams were not within the acceptable tolerance level (+/-3%). Quality assurance in some radiation centers was poor and staffing levels were inadequate. We found poor compliance with internationally accepted tolerance levels for dose calibration of radiotherapy beams at radiation therapy centers in Saudi Arabia. Analysis of medical physics staffing revealed severe discrepancies from those recommended by international guidelines .We recommend that radiation therapy centers be adequately staffed with qualified medical physics personnel and that periodic audit programs be required a governmental body. (author)
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Radiation therapy for the treatment of feline advanced cutaneous squamous cell carcinoma
International Nuclear Information System (INIS)
Cunha, S.C.S.; Corgozinho, K.B.; Ferreira, A.M.R; Carvalho, L.A.V.; Holguin, P.G.
2014-01-01
The efficacy of radiation therapy for feline advanced cutaneous squamous cell carcinoma was evaluated. A full course radiation therapy protocol was applied to six cats showing single or multiple facial squamous cell carcinomas, in a total of seven histologically confirmed neoplastic lesions. Of the lesions, one was staged as T 1 , and six as T 4 according to WHO staging system of epidermal tumors. The animals were submitted to twelve radiation fractions of 4 Gy each, on a Monday-Wednesday-Friday schedule, and the equipment used was an orthovoltage unit. Energy used was 120 kV, 15 mA and 2 mm aluminum filter. The cats were evaluated during the treatment and 30 and 60 days after the end of the radiation therapy. In this study, 87% of the lesions had complete remission and 13% partial remission to the treatment. Side effects were considered mild according to Veterinary Radiation Therapy Oncology Group Toxicity criteria, and included erythema, epilation and rhinitis. Radiation Therapy was considered safe for feline cutaneous squamous cell carcinoma, leading to mild side effects and can represent a good therapeutic option. (author)
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An implantable radiation dosimeter for use in external beam radiation therapy
International Nuclear Information System (INIS)
Scarantino, Charles W.; Ruslander, David M.; Rini, Christopher J.; Mann, Gregory G.; Nagle, H. Troy; Black, Robert D.
2004-01-01
An implantable radiation dosimeter for use with external beam therapy has been developed and tested both in vitro and in canines. The device uses a MOSFET dosimeter and is polled telemetrically every day during the course of therapy. The device is designed for permanent implantation and also acts as a radiographic fiducial marker. Ten dogs (companion animals) that presented with spontaneous, malignant tumors were enrolled in the study and received an implant in the tumor CTV. Three dogs received an additional implant in collateral normal tissue. Radiation therapy plans were created for the animals and they were treated with roughly 300 cGy daily fractions until completion of the prescribed cumulative dose. The primary endpoints of the study were to record any adverse events due to sensor placement and to monitor any movement away from the point of placement. No adverse events were recorded. Unacceptable device migration was experienced in two subjects and a retention mechanism was developed to prevent movement in the future. Daily dose readings were successfully acquired in all subjects. A rigorous in vitro calibration methodology has been developed to ensure that the implanted devices maintain an accuracy of ±3.5% relative to an ionization chamber standard. The authors believe that an implantable radiation dosimeter is a practical and powerful tool that fosters individualized patient QA on a daily basis
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Postoperative Radiation Therapy of Craniopharyngioma
International Nuclear Information System (INIS)
Shin, Kyung Hwan; Kim, Il Han; Park, Charn Il; Cho, Byung Kyu; Yun, Hyong Geln
1993-01-01
Between December 1979 and September 1989, 23 patients with craniopharyngioma who underwent surgery and postoperative radiation therapy were retrospectively evaluated to assess the efficacy of this management at the Department of Therapeutic Radiology, Seoul National University Hospital. Total removal of tumor was attempted in all patients. Of these, surgeons tried total removal in eight patients, but revealed residual mass by postoperative CT, and partial removal was done in 15 patients. The morphology of tumor on the operative finding was grouped into three types : cystic 13 (57%), solid 4 (17%), and mixed 6 (26%). Cystic type was predominant in ≤20 years old group. Actuarial overall survival rates at 5 and 10 years were 95% and 81% respectively and actuarial tumor control rates were 74% and 50%. Surgical extent was not related to the survival rates(p=0.41). Pediatric and adolescent Patients(age of ≤20 year) had a trend of better survival than that of adult patients(p=0.10). The results indicated that limited surgical excision followed by radiation therapy is recommended when total excision is not possible
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Postoperative Radiation Therapy of Craniopharyngioma
Energy Technology Data Exchange (ETDEWEB)
Shin, Kyung Hwan; Kim, Il Han; Park, Charn Il; Cho, Byung Kyu [Seoul National University College of Medicine, Seoul (Korea, Republic of); Yun, Hyong Geln [Korea Cancer Center Hospital, Seoul (Korea, Republic of)
1993-06-15
Between December 1979 and September 1989, 23 patients with craniopharyngioma who underwent surgery and postoperative radiation therapy were retrospectively evaluated to assess the efficacy of this management at the Department of Therapeutic Radiology, Seoul National University Hospital. Total removal of tumor was attempted in all patients. Of these, surgeons tried total removal in eight patients, but revealed residual mass by postoperative CT, and partial removal was done in 15 patients. The morphology of tumor on the operative finding was grouped into three types : cystic 13 (57%), solid 4 (17%), and mixed 6 (26%). Cystic type was predominant in {<=}20 years old group. Actuarial overall survival rates at 5 and 10 years were 95% and 81% respectively and actuarial tumor control rates were 74% and 50%. Surgical extent was not related to the survival rates(p=0.41). Pediatric and adolescent Patients(age of {<=}20 year) had a trend of better survival than that of adult patients(p=0.10). The results indicated that limited surgical excision followed by radiation therapy is recommended when total excision is not possible.
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Radiation therapy of peritoneal mesothelioma
International Nuclear Information System (INIS)
Lederman, G.; Recht, A.
1986-01-01
The role of radiation therapy in the treatment of peritoneal mesotheliomas remains ill-defined despite its association with the few long-term survivals reported for this disease. The rationale for local therapy is clear as the disease most often is confined to the peritoneal cavity at the time of initial diagnosis and remains there for much of the subsequent course. Effective local treatment of this intra-abdominal disease would likely improve survival. The absence of randomized studies has made analysis of the various treatments of the disease and the few reported success difficult. Nonetheless, scrutiny of the available data may offer insights and guide future clinical trials, as well as the clinician responsible for the treatment of current patients with peritoneal mesothelioma. The radiotherapeutic approach to oncology stresses anatomic considerations in an attempt to understand the patterns of spread of the primary tumor. The observed location and bulk of disease by clinical examination, radiologic study, surgical exploration, and autopsy suggest mechanisms of metastases (direct extension, lymphatic or hematogenous). This dictates the administration of radiation that best achieves a successful outcome
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Energy Technology Data Exchange (ETDEWEB)
Shin, Sung Pil; Kim, Tae Hyung; So, Woon Young; Back, Geum Mun [Dept. of Medical Health Science, Graduate School, Kangwon National University, Chuncheon (Korea, Republic of)
2016-12-15
We are evaluated the usefulness of radiation treatment planning applied respiration factor for stereotactic body radiation therapy in the lung cancer. Four dimensional computed tomography images were obtained in 10 patients with lung cancer. The radiation treatment plans were established total lung volume according to respiration images (new method) and conventional method. We was analyzed in the lung volume, radiation absorbed dose of lung and main organs (ribs, tracheobronchus, esophagus, spinal cord) around the tumor, respectively. We were confirmed that lung volume and radiation absorbed dose of lung and main organs around the tumor deference according to applied respiration. In conclusion, radiation treatment planning applied respiration factor seems to be useful for stereotactic body radiation therapy in the lung cancer.
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MOSFET dosimetry of the radiation therapy microbeams at the European synchrotron radiation facility
International Nuclear Information System (INIS)
Rozenfeld, A.; Lerch, M.
2002-01-01
Full text: We have developed an innovative on-line MOSFET readout system for use in the quality assurance of radiation treatment beams. Recently the system has found application in areas where excellent spatial resolution is also a requirement in the quality assurance process, for example IMRT, and microbeam radiation therapy. The excellent spatial resolution is achieved by using a quadruple RADFET TM chip in 'edge on' mode. In developing this approach we have found that the system can be utilised to determine any error in the beam profile measurements due to misalignment of RADFET with respect to the radiation beam or microbeam. Using this approach will ensure that the excellent spatial resolution of the RADFET used in 'edge-on' mode is fully utilised. In this work we report on dosimetry measurements performed at the microbeam radiation therapy beamline located at the European Synchrotron Radiation Facility. The synchrotron planar array microbeam with size 10-30 μm and pitch ∼200 μm has found an important application in microbeam radiation therapy (MRT) of brain tumours in infants for whom other kinds of radiotherapy are inadequate and/or unsafe. The radiation damage from an array of parallel microbeams correlates strongly with the range of peak-valley dose ratios (PVDR), ie, the range of the ratio of the absorbed dose to tissue directly in line with the mid-plane of the microbeam to that in the mid-plane between adjacent microbeams. Novel physical dosimetry of the microbeams using the online MOSFET reader system will be presented. Comparison of the experimental results with both GaF film measurements and Monte Carlo computer-simulated dosimetry are described here for selected points in the peak and valley regions of a microbeam-irradiated tissue phantom
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Subacute brain atrophy induced by radiation therapy to the malignant brain tumors
International Nuclear Information System (INIS)
Asai, Akio; Matsutani, Masao; Takakura, Kintomo.
1987-01-01
In order to analyze brain atrophy after radiation therapy to the brain tumors, we calculated a CSF-cranial volume ratio on CT scan as an index of brain atrophy, and estimated dementia-score by Hasegawa's method in 91 post-irradiated patients with malignant brain tumors. Radiation-induced brain atrophy was observed in 51 out of 91 patients (56 %) and dementia in 23 out of 47 patients (49 %). These two conditions were closely related, and observed significantly more often in aged and whole-brain-irradiated patients. As radiation-induced brain atrophy accompanied by dementia appeared 2 - 3 months after the completion of radiation therapy, it should be regarded as a subacute brain injury caused by radiation therapy. (author)
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[The effectiveness of magnetic therapy of grade I-II radiation pneumofibrosis].
Grushina, T I
2014-01-01
Radiation therapy of malignant tumours of the chest organs may result in radiation damage of the lungs. To prevent and reduce radiation-induced lung injuries, new types of radiation therapy have been developed, a number of various modifiers investigated, the methods of pharmacotherapy and physiotherapy proposed. The present study involved 37 patients presenting with radiation pneumofibrosis, including 7 ones with lung cancer and 30 patients with breast cancer. Based on the results of clinical, radiographic, and functional investigations, grade 1 and II pneumofibrosis was diagnosed in 20 and 17 patients respectively. After the application of an alternating magnetic field during 15 days, all the patients experience the overall regression of clinical symptoms and disorders of respiratory biomechanics. However, it seems premature to draw a definitive conclusion about the effectiveness of magnetic therapy of grade 1 and II radiation pneumofibrosis before the extensive in-depth investigations are carried out based on a large clinical material including the results of long-term follow-up studies and continuous monitoring.
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Radiation therapy for neovascular age-related macular degeneration
Directory of Open Access Journals (Sweden)
Robert Petrarca
2011-01-01
Full Text Available Robert Petrarca, Timothy L JacksonDepartment of Ophthalmology, King’s College Hospital NHS Foundation Trust, London, UKAbstract: Antivascular endothelial growth factor (anti-VEGF therapies represent the standard of care for most patients presenting with neovascular (wet age-related macular degeneration (neovascular AMD. Anti-VEGF drugs require repeated injections and impose a considerable burden of care, and not all patients respond. Radiation targets the proliferating cells that cause neovascular AMD, including fibroblastic, inflammatory, and endothelial cells. Two new neovascular AMD radiation treatments are being investigated: epimacular brachytherapy and stereotactic radiosurgery. Epimacular brachytherapy uses beta radiation, delivered to the lesion via a pars plana vitrectomy. Stereotactic radiosurgery uses low voltage X-rays in overlapping beams, directed onto the lesion. Feasibility data for epimacular brachytherapy show a greatly reduced need for anti-VEGF therapy, with a mean vision gain of 8.9 ETDRS letters at 12 months. Pivotal trials are underway (MERLOT, CABERNET. Preliminary stereotactic radiosurgery data suggest a mean vision gain of 8 to 10 ETDRS letters at 12 months. A large randomized sham controlled stereotactic radiosurgery feasibility study is underway (CLH002, with pivotal trials to follow. While it is too early to conclude on the safety and efficacy of epimacular brachytherapy and stereotactic radiosurgery, preliminary results are positive, and these suggest that radiation offers a more durable therapeutic effect than intraocular injections.Keywords: wet age-related macular degeneration, neovascular, radiation therapy, epimacular brachytherapy, stereotactic radiosurgery, anti-VEGF
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Megavoltage radiation therapy: Meeting the technological needs
International Nuclear Information System (INIS)
Van Dyk, J.
2002-01-01
Full text: In its simplest description, the purpose of radiation therapy is to hit the target and to miss all other parts of the patient. While there are multiple technological methods available for doing this, the actual radiation treatment needs to be considered in the broader context of the total radiation treatment process. This process contains multiple steps, each of which has an impact on the quality of the treatment and on the possible clinical outcome. One crucial step in this process is the determination of the location and extent of the disease relative to the adjacent normal tissues. This can be done in a variety of ways, ranging from simple clinical examination to the use of complex 3-D imaging, sometimes aided by contrast agents. As part of this localization process, it is very important that patient immobilization procedures be implemented to ensure that the same patient position will be used during both the planning and the daily treatment stages. With the knowledge of the location of the target and the critical tissues, decisions can be made about the appropriate beam arrangements to provide adequate tumour coverage while sparing the healthy tissues. This beam arrangement may have to be confirmed on a therapy simulator prior to actual implementation of the radiation treatment. In summary, the treatment process includes diagnosis, patient immobilization, target and normal tissue localization, beam selection, beam shaping, dose calculation, technique optimization, simulation, prescription, treatment verification and, finally, treatment. Dependent on the type of disease, it is not necessary that every patient undergoes all of the steps in the process; however, it is necessary that each step of the process used for a particular patient be carried out with the greatest accuracy. Uncertainties at any stage of the process will be carried through to subsequent stages and have an impact on clinical outcome. It is, therefore, important to recognize, when
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A prospective study of quality of life in breast cancer patients undergoing radiation therapy
Directory of Open Access Journals (Sweden)
Canhua Xiao, PhD, RN
2016-01-01
Conclusions: Radiation therapy did not worsen QOL in breast cancer patients. However, pre-radiation therapy patient characteristics including BMI and perceived stress may be used to identify women who may experience decreased physical and mental function during and up to 1 year after radiation therapy.
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Wust, Peter; Joswig, Marc; Graf, Reinhold; Böhmer, Dirk; Beck, Marcus; Barelkowski, Thomasz; Budach, Volker; Ghadjar, Pirus
2017-09-01
For high-dose radiation therapy (RT) of prostate cancer, image-guided (IGRT) and intensity-modulated RT (IMRT) approaches are standard. Less is known regarding comparisons of different IGRT techniques and the resulting residual errors, as well as regarding their influences on dose distributions. A total of 58 patients who received tomotherapy-based RT up to 84 Gy for high-risk prostate cancer underwent IGRT based either on daily megavoltage CT (MVCT) alone (n = 43) or the additional use of gold markers (n = 15) under routine conditions. Planned Adaptive (Accuray Inc., Madison, WI, USA) software was used for elaborated offline analysis to quantify residual interfractional prostate positioning errors, along with systematic and random errors and the resulting safety margins after both IGRT approaches. Dosimetric parameters for clinical target volume (CTV) coverage and exposition of organs at risk (OAR) were also analyzed and compared. Interfractional as well as intrafractional displacements were determined. Particularly in the vertical direction, residual interfractional positioning errors were reduced using the gold marker-based approach, but dosimetric differences were moderate and the clinical relevance relatively small. Intrafractional prostate motion proved to be quite high, with displacements of 1-3 mm; however, these did not result in additional dosimetric impairments. Residual interfractional positioning errors were reduced using gold marker-based IGRT; however, this resulted in only slightly different final dose distributions. Therefore, daily MVCT-based IGRT without markers might be a valid alternative.
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The pitfalls of dosimetric commissioning for intensity modulated radiation therapy
International Nuclear Information System (INIS)
Tohyama, Naoki; Kodama, Takashi; Hatano, K.
2013-01-01
Intensity modulated radiation therapy (IMRT) allows higher radiation dose to be focused to the target volumes while minimizing the dose to OAR. To start of clinical treatment in IMRTvwe must perform commissioning strictly than 3D-conformal radiotherapy (CRT). In this report, pitfalls of dosimetric commissioning for intensity modulated radiation therapy were reviewed. Multileaf collimator (MLC) offsets and MLC transmissions are important parameters in commissioning of RTPS for IMRT. Correction of depth scaling and fluence scaling is necessary for dose measurement using solid phantom. (author)
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Intensity-modulated radiation therapy clinical evidence and techniques
Nishimura, Yasumasa
2015-01-01
Successful clinical use of intensity-modulated radiation therapy (IMRT) represents a significant advance in radiation oncology. Because IMRT can deliver high-dose radiation to a target with a reduced dose to the surrounding organs, it can improve the local control rate and reduce toxicities associated with radiation therapy. Since IMRT began being used in the mid-1990s, a large volume of clinical evidence of the advantages of IMRT has been collected. However, treatment planning and quality assurance (QA) of IMRT are complicated and difficult for the clinician and the medical physicist. This book, by authors renowned for their expertise in their fields, provides cumulative clinical evidence and appropriate techniques for IMRT for the clinician and the physicist. Part I deals with the foundations and techniques, history, principles, QA, treatment planning, radiobiology and related aspects of IMRT. Part II covers clinical applications with several case studies, describing contouring and dose distribution with cl...
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Management of stage III thymoma with postoperative radiation therapy
International Nuclear Information System (INIS)
Krueger, J.B.; Sagerman, R.H.; King, G.A.
1987-01-01
The results of postoperative radiation therapy in 12 patients with Stage III thymoma treated during the period 1966-1986 were reviewed. Surgical therapy consisted of total resection in one, subtotal resection in seven, and biopsy only in four. Megavoltage irradiation in the dose range of 3,000-5,600 cGy was employed, with the majority receiving a dose of at least 5,000 cGy. The local control rate was 67%. The actuarial 5-year observed and adjusted survival rates were 57% and 75%, respectively. These results indicate that postoperative radiation therapy is an effective therapeutic modality in the control of Stage III thymoma
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Radiation therapy for prostate cancer.
Koontz, Bridget F; Lee, W Robert
2013-07-01
Radiation therapy is an effective treatment for newly diagnosed prostate cancer, salvage treatment, or for palliation of advanced disease. Herein we briefly discuss the indications, results, and complications associated with brachytherapy and external beam radiotherapy, when used as monotherapy and in combination with each other or androgen deprivation. Copyright © 2013 Elsevier Inc. All rights reserved.
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Place of radiation therapy in the treatment of Hodgkin's disease
International Nuclear Information System (INIS)
Hellman, S.; Mauch, P.; Goodman, R.L.; Rosenthal, D.S.; Moloney, W.C.
1978-01-01
Between April 1969, and December 1974, 216 successive surgically-staged IA-IIIB Hodgkin's disease patients were seen and treated at the Joint Center for Radiation Therapy. Patients with stages IA and IIA disease received mantle and para-aortic-splenic pedicle irradiation alone and have a probability of relapse-free survival of 97 percent and 80 percent, respectively. Patients with stage IIIA disease were treated with total-nodal irradiation (TNI) alone and have a 51 percent relapse-free and 82 percent overall survival. In spite of the high relapse rate in stage IIIA patients, the majority are currently disease-free following retreatment with MOPP chemotherapy. Stage IIB and IIIB patients received either radiation therapy alone or combined with chemotherapy. While the relapse-free survival is similar in stage IIB patients with or without the addition of chemotherapy, combined TNI and MOPP chemotherapy in stage IIIB patients has provided a superior relapse-free survival (74 percent) when compared to patients treated with TNI alone. There have been 3 mantle irradiation-related deaths in 209 patients treated (1.5 percent); in contrast, there have been 6 deaths related to combined-modality treatment in 74 patients at risk (8 percent). We continue to advocate the minimum therapy needed to produce uncomplicated cure. We feel that this is achieved with radiation therapy alone in stages IA and IIA disease without extensive mediastinal involvement and with combined modality therapy in stage IIIB disease. The role of combined modality therapy in place of radiation therapy alone in stage IIB and IIIA disease is less certain
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TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists
International Nuclear Information System (INIS)
Orton, C; Borras, C; Carlson, D
2014-01-01
Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protection will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 20–40 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples of how
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TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists
Energy Technology Data Exchange (ETDEWEB)
Orton, C [Wayne State University, Grosse Pointe, MI (United States); Borras, C [Radiological Physics and Health Services, Washington, DC (United States); Carlson, D [Yale University School of Medicine, New Haven, CT (United States)
2014-06-15
Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protection will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 20–40 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples of how
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Treatment of Head and Neck Paragangliomas With External Beam Radiation Therapy
International Nuclear Information System (INIS)
Dupin, Charles; Lang, Philippe; Dessard-Diana, Bernadette; Simon, Jean-Marc; Cuenca, Xavier; Mazeron, Jean-Jacques; Feuvret, Loïc
2014-01-01
Purpose: To retrospectively assess the outcomes of radiation therapy in patients with head and neck paragangliomas. Methods and Materials: From 1990 to 2009, 66 patients with 81 head and neck paragangliomas were treated by conventional external beam radiation therapy in 25 fractions at a median dose of 45 Gy (range, 41.4-68 Gy). One case was malignant. The median gross target volume and planning target volume were 30 cm 3 (range, 0.9-243 cm 3 ) and 116 cm 3 (range, 24-731 cm 3 ), respectively. Median age was 57.4 years (range, 15-84 years). Eleven patients had multicentric lesions, and 8 had family histories of paraganglioma. Paragangliomas were located in the temporal bone, the carotid body, and the glomus vagal in 51, 18, and 10 patients, respectively. Forty-six patients had exclusive radiation therapy, and 20 had salvage radiation therapy. The median follow-up was 4.1 years (range, 0.1-21.2 years). Results: One patient had a recurrence of temporal bone paraganglioma 8 years after treatment. The actuarial local control rates were 100% at 5 years and 98.7% at 10 years. Patients with multifocal tumors and family histories were significantly younger (42 years vs 58 years [P=.002] and 37 years vs 58 years [P=.0003], respectively). The association between family predisposition and multifocality was significant (P<.001). Two patients had cause-specific death within the 6 months after irradiation. During radiation therapy, 9 patients required hospitalization for weight loss, nausea, mucositis, or ophthalmic zoster. Two late vascular complications occurred (middle cerebral artery and carotid stenosis), and 2 late radiation-related meningiomas appeared 15 and 18 years after treatment. Conclusion: Conventional external beam radiation therapy is an effective and safe treatment option that achieves excellent local control; it should be considered as a first-line treatment of choice for head and neck paragangliomas
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An international intercomparison of absorbed dose measurements for radiation therapy
International Nuclear Information System (INIS)
Taiman Kadni; Noriah Mod Ali
2002-01-01
Dose intercomparison on an international basis has become an important component of quality assurance measurement i.e. to check the performance of absorbed dose measurements in radiation therapy. The absorbed dose to water measurements for radiation therapy at the SSDL, MINT have been regularly compared through international intercomparison programmes organised by the IAEA Dosimetry Laboratory, Seibersdorf, Austria such as IAEA/WHO TLD postal dose quality audits and the Intercomparison of therapy level ionisation chamber calibration factors in terms of air kerma and absorbed dose to water calibration factors. The results of these intercomparison in terms of percentage deviations for Cobalt 60 gamma radiation and megavoltage x-ray from medical linear accelerators participated by the SSDL-MINT during the year 1985-2001 are within the acceptance limit. (Author)
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Radiation therapy of penile cancer: six to ten-year follow-up
International Nuclear Information System (INIS)
Grabstald, H.; Kelley, C.D.
1980-01-01
Ten patients with penile cancer were treated with radiation therapy between 1968 and 1973. Nine of ten remain free of disease though in 1 patient a new penile primary developed eight years after the radiation therapy and was treated by partial penectomy. One patient died following surgery for ''bleeding ulcer.'' He was free of penile cancer five years after radiation. The most common complication is urethral stricture and skin telangiectasia
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Radiation therapy planning for early-stage Hodgkin lymphoma
DEFF Research Database (Denmark)
Maraldo, Maja V; Dabaja, Bouthaina S; Filippi, Andrea R
2015-01-01
PURPOSE: Early-stage Hodgkin lymphoma (HL) is a rare disease, and the location of lymphoma varies considerably between patients. Here, we evaluate the variability of radiation therapy (RT) plans among 5 International Lymphoma Radiation Oncology Group (ILROG) centers with regard to beam arrangements...... axillary disease, and 1 had disease in the neck only. The median age at diagnosis was 34 years (range, 21-74 years), and 5 patients were male. Of the resulting 50 treatment plans, 15 were planned with volumetric modulated arc therapy (1-4 arcs), 16 with intensity modulated RT (3-9 fields), and 19 with 3...
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PET/CT in Radiation Therapy Planning
DEFF Research Database (Denmark)
Specht, Lena; Berthelsen, Anne Kiil
2018-01-01
Radiation therapy (RT) is an important component of the management of lymphoma patients. Most lymphomas are metabolically active and accumulate 18F-fluorodeoxyglucose (FDG). Positron emission tomography with computer tomography (PET/CT) imaging using FDG is used routinely in staging and treatment...
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DEFF Research Database (Denmark)
Westberg, Jonas; Jensen, Henrik R; Bertelsen, Anders
2010-01-01
In modern radiotherapy accelerators are equipped with 3D cone-beam CT (CBCT) which is used to verify patient position before treatment. The verification is based on an image registration between the CBCT acquired just before treatment and the CT scan made for the treatment planning. The purpose...... of this study is to minimise the scan time of the CBCT without compromising the accuracy of the image registration in IGRT....
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A strategy to develop and implement Canadian standards for quality assurance in radiation therapy
International Nuclear Information System (INIS)
1999-05-01
In Canada, the Atomic Energy Control Board (AECB) regulates the limits of radiation exposure to the public and to workers in industry. In 1993, it discussed the fact that the safety of radiation therapy patients who receive medical exposures is not regulated [AE93]. The Group of Medical Advisors (GMA) to the AECB initiated a research contract to review quality assurance in Canadian radiation oncology centres and nuclear medicine departments. The review [MA95] revealed that the level of quality assurance in radiation therapy facilities varied across the country. As a result, the GMA undertook its own review of quality assurance in radiation therapy centres and made recommendations on how to achieve a uniform national system [MA98]. In response to the GMA report, the President of the AECB formed a Joint Working Group (JWG-11) to propose how Canadian Standards for Quality Assurance in Radiation Therapy could be developed and implemented. These national standards for quality assurance will serve as a common basis for establishing and evaluating quality assurance programs at individual radiation therapy centres. These standards should address the structure of quality assurance programs and quality assurance for radiation therapy equipment, personnel, and procedures. (author)
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The breast cancer patient's experience of making radiation therapy treatment decisions
International Nuclear Information System (INIS)
Halkett, Georgia; Scutter, Sheila; Arbon, Paul; Borg, Martin
2005-01-01
Women who are diagnosed with breast cancer have many decisions to make during the course of their treatment. The aims of this paper are to describe the women's experience of making radiation therapy treatment decisions for early breast cancer and to explore how women feel about receiving radiation therapy. An in-depth understanding of the women's experience was developed using a qualitative research approach underpinned by hermeneutic phenomenology. In-depth interviews were conducted with 18 women who had completed treatment for early breast cancer. The themes that emerged from the data were: being challenged, getting ready, beyond control, regaining a sense of control and getting through it. This study provides health professionals with an initial understanding of the women's perspective of the experience of making radiation therapy treatment decisions for early breast cancer. This study concludes by suggesting that further research needs to be conducted to gain an understanding of how other patients feel about treatment decision making and radiation therapy. Copyright (2005) Australian Institute of Radiography
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Intra-oral cone radiation therapy for selected carcinomas of the oral cavity
International Nuclear Information System (INIS)
Wang, C.C.; Doppke, K.P.; Biggs, P.J.
1983-01-01
A study of 101 patients with early carcinomas of the oral cavity, T1 and T2, treated by external cobalt 60 beam and/or intra-oral cone (IOC) radiation therapy between 1964 through 1980 was made. The two year disease-free survival rate, including surgical salvage, was 88% and the local control rate was 85%. The incidence of radiation complications, i.e., soft tissue ulceration and/or osteoradionecrosis, was 14% and varied with various tumor sites and radiation doses delivered. The present review shows that local control and radiation complications are closely related to radiation doses and varies with different tumor sites of the oral cavity. Radiation therapy dosages expressed in terms of TDF values for these lesions are herein recommended. With proper selections of lesions arising from the oral cavity, combined external beam and IOC radiation therapy has been found extremely efficacious in achieving good local tumor control and high survival rates with excellent cosmetic and functional results and minimum radiation sequalae
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TomoTherapy MLC verification using exit detector data
Energy Technology Data Exchange (ETDEWEB)
Chen Quan; Westerly, David; Fang Zhenyu; Sheng, Ke; Chen Yu [TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 (United States); Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Xinghua Cancer Hospital, Xinghua, Jiangsu 225700 (China); Department of Radiation Oncology, University of California-Los Angeles, Los Angeles, California 90095 (United States); TomoTherapy Inc., 1240 Deming Way, Madison, Wisconsin 53717 (United States)
2012-01-15
Purpose: Treatment delivery verification (DV) is important in the field of intensity modulated radiation therapy (IMRT). While IMRT and image guided radiation therapy (IGRT), allow us to create more conformal plans and enables the use of tighter margins, an erroneously executed plan can have detrimental effects on the treatment outcome. The purpose of this study is to develop a DV technique to verify TomoTherapy's multileaf collimator (MLC) using the onboard mega-voltage CT detectors. Methods: The proposed DV method uses temporal changes in the MVCT detector signal to predict actual leaf open times delivered on the treatment machine. Penumbra and scattered radiation effects may produce confounding results when determining leaf open times from the raw detector data. To reduce the impact of the effects, an iterative, Richardson-Lucy (R-L) deconvolution algorithm is applied. Optical sensors installed on each MLC leaf are used to verify the accuracy of the DV technique. The robustness of the DV technique is examined by introducing different attenuation materials in the beam. Additionally, the DV technique has been used to investigate several clinical plans which failed to pass delivery quality assurance (DQA) and was successful in identifying MLC timing discrepancies as the root cause. Results: The leaf open time extracted from the exit detector showed good agreement with the optical sensors under a variety of conditions. Detector-measured leaf open times agreed with optical sensor data to within 0.2 ms, and 99% of the results agreed within 8.5 ms. These results changed little when attenuation was added in the beam. For the clinical plans failing DQA, the dose calculated from reconstructed leaf open times played an instrumental role in discovering the root-cause of the problem. Throughout the retrospective study, it is found that the reconstructed dose always agrees with measured doses to within 1%. Conclusions: The exit detectors in the TomoTherapy treatment
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TomoTherapy MLC verification using exit detector data
International Nuclear Information System (INIS)
Chen Quan; Westerly, David; Fang Zhenyu; Sheng, Ke; Chen Yu
2012-01-01
Purpose: Treatment delivery verification (DV) is important in the field of intensity modulated radiation therapy (IMRT). While IMRT and image guided radiation therapy (IGRT), allow us to create more conformal plans and enables the use of tighter margins, an erroneously executed plan can have detrimental effects on the treatment outcome. The purpose of this study is to develop a DV technique to verify TomoTherapy's multileaf collimator (MLC) using the onboard mega-voltage CT detectors. Methods: The proposed DV method uses temporal changes in the MVCT detector signal to predict actual leaf open times delivered on the treatment machine. Penumbra and scattered radiation effects may produce confounding results when determining leaf open times from the raw detector data. To reduce the impact of the effects, an iterative, Richardson-Lucy (R-L) deconvolution algorithm is applied. Optical sensors installed on each MLC leaf are used to verify the accuracy of the DV technique. The robustness of the DV technique is examined by introducing different attenuation materials in the beam. Additionally, the DV technique has been used to investigate several clinical plans which failed to pass delivery quality assurance (DQA) and was successful in identifying MLC timing discrepancies as the root cause. Results: The leaf open time extracted from the exit detector showed good agreement with the optical sensors under a variety of conditions. Detector-measured leaf open times agreed with optical sensor data to within 0.2 ms, and 99% of the results agreed within 8.5 ms. These results changed little when attenuation was added in the beam. For the clinical plans failing DQA, the dose calculated from reconstructed leaf open times played an instrumental role in discovering the root-cause of the problem. Throughout the retrospective study, it is found that the reconstructed dose always agrees with measured doses to within 1%. Conclusions: The exit detectors in the TomoTherapy treatment systems
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Radiation ulcers in patients with cancer of the torgue after 252Cf therapy
International Nuclear Information System (INIS)
Galantseva, G.F.; Guseva, L.I.; Plichko, V.I.
1984-01-01
Interstitial therapy with 252 Cf was conducted for 57 patients with cancer of the tongue. It was established that clinical course of radiation tungue ulcers after interstitial therapy with 252 Cf doesn't differ sufficiently from the course of radiation injuries, occurring after γ-radiation application. Radiation ulcers are often observed in patients after the treatment of recurrent and residual tumors with 252 Cf (in 33% of patients); the ulcers appeared in 15% of cases in patients after the treatment of initial ulcers tumors. Conservative treatment provide the cure of radiation tongUe ulcers after interstitial therapy with 252 Cf
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Radiation therapy for resistant sternal hydatid disease
International Nuclear Information System (INIS)
Ulger, S.; Barut, H.; Tunc, M.; Aydinkarahaliloglu, E.; Aydin, E.; Karaoglanoglu, N.; Gokcek, A.
2013-01-01
Hydatid disease is a zoonotic infectious disease for which there are known treatment procedures and effective antibiotics; however, there are resistant cases that do not respond to medication or surgery. We report a case diagnosed as hydatid disease of the chest wall and treated with radiation therapy (RT) after medical and surgical therapy had failed. In conclusion, RT represents an alternative treatment modality in resistant cases. (orig.)
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Multibeam radiation therapy treatment application
International Nuclear Information System (INIS)
Manens, J.P.; Le Gall, G.; Chenal, C.; Ben Hassel, M.; Fresne, F.; Barillot, C.; Gibaud, B.; Lemoine, D.; Bouliou, A.; Scarabin, J.M.
1991-01-01
A software package has been developed for multibeam radiation therapy treatment application. We present in this study a computer-assisted dosimetric planning procedure which includes: i), an analytical stage for setting up the large volume via 2D and 3D displays; ii), a planning stage for issue of a treatment strategy including dosimetric simulations; and iii), a treatment stage to drive the target volume to the radiation unit isocenter. The combined use of stereotactic methods and multimodality imagery ensures spatial coherence and makes target definition and cognition of structure environment more accurate. The dosimetric planning suited to the spatial reference (the stereotactic frame) guarantees optimal distribution of the dose, computed by the original 3D volumetric algorithm. A computer-driven chair-framework cluster was designed to position the target volume at the radiation unit isocenter [fr
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Intensity-modulated radiation therapy: a review with a physics perspective.
Cho, Byungchul
2018-03-01
Intensity-modulated radiation therapy (IMRT) has been considered the most successful development in radiation oncology since the introduction of computed tomography into treatment planning that enabled three-dimensional conformal radiotherapy in 1980s. More than three decades have passed since the concept of inverse planning was first introduced in 1982, and IMRT has become the most important and common modality in radiation therapy. This review will present developments in inverse IMRT treatment planning and IMRT delivery using multileaf collimators, along with the associated key concepts. Other relevant issues and future perspectives are also presented.
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Directory of Open Access Journals (Sweden)
Sarah E Hegarty
Full Text Available To evaluate the influence of timing of salvage and adjuvant radiation therapy on outcomes after prostatectomy for prostate cancer.Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we identified prostate cancer patients diagnosed during 1995-2007 who had one or more adverse pathological features after prostatectomy. The final cohort of 6,137 eligible patients included men who received prostatectomy alone (n = 4,509 or with adjuvant (n = 894 or salvage (n = 734 radiation therapy. Primary outcomes were genitourinary, gastrointestinal, and erectile dysfunction events and survival after treatment(s.Radiation therapy after prostatectomy was associated with higher rates of gastrointestinal and genitourinary events, but not erectile dysfunction. In adjusted models, earlier treatment with adjuvant radiation therapy was not associated with increased rates of genitourinary or erectile dysfunction events compared to delayed salvage radiation therapy. Early adjuvant radiation therapy was associated with lower rates of gastrointestinal events that salvage radiation therapy, with hazard ratios of 0.80 (95% CI, 0.67-0.95 for procedure-defined and 0.70 (95% CI, 0.59, 0.83 for diagnosis-defined events. There was no significant difference between ART and non-ART groups (SRT or RP alone for overall survival (HR = 1.13 95% CI = (0.96, 1.34 p = 0.148.Radiation therapy after prostatectomy is associated with increased rates of gastrointestinal and genitourinary events. However, earlier radiation therapy is not associated with higher rates of gastrointestinal, genitourinary or sexual events. These findings oppose the conventional belief that delaying radiation therapy reduces the risk of radiation-related complications.
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Fiber-optic dosimeters for radiation therapy
Li, Enbang; Archer, James
2017-10-01
According to the figures provided by the World Health Organization, cancer is a leading cause of death worldwide, accounting for 8.8 million deaths in 2015. Radiation therapy, which uses x-rays to destroy or injure cancer cells, has become one of the most important modalities to treat the primary cancer or advanced cancer. The newly developed microbeam radiation therapy (MRT), which uses highly collimated, quasi-parallel arrays of x-ray microbeams (typically 50 μm wide and separated by 400 μm) produced by synchrotron sources, represents a new paradigm in radiotherapy and has shown great promise in pre-clinical studies on different animal models. Measurements of the absorbed dose distribution of microbeams are vitally important for clinical acceptance of MRT and for developing quality assurance systems for MRT, hence are a challenging and important task for radiation dosimetry. On the other hand, during the traditional LINAC based radiotherapy and breast cancer brachytherapy, skin dose measurements and treatment planning also require a high spatial resolution, tissue equivalent, on-line dosimeter that is both economical and highly reliable. Such a dosimeter currently does not exist and remains a challenge in the development of radiation dosimetry. High resolution, water equivalent, optical and passive x-ray dosimeters have been developed and constructed by using plastic scintillators and optical fibers. The dosimeters have peak edge-on spatial resolutions ranging from 50 to 500 microns in one dimension, with a 10 micron resolution dosimeter under development. The developed fiber-optic dosimeters have been test with both LINAC and synchrotron x-ray beams. This work demonstrates that water-equivalent and high spatial resolution radiation detection can be achieved with scintillators and optical fiber systems. Among other advantages, the developed fiber-optic probes are also passive, energy independent, and radiation hard.
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International Nuclear Information System (INIS)
Goo, Jang Hyeon; Won, Hui Su; Hong, Joo Wan; Chang, Nam Jun; Park, Jin Hong
2014-01-01
The aim of this study was to appraise properties for radiation therapy techniques and effectiveness of time and economy to a patient in the case of applying flattening filter-free (3F) and flattening filter (2F) beam to the radiation therapy. Alderson rando phantom was scanned for computed tomography image. Treatment plans for intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and stereotactic body radiation therapy (SBRT) with 3F and 2F beam were designed for prostate cancer. To evaluate the differences between the 3F and 2F beam, total monitor units (MUs), beam on time (BOT) and gantry rotation time (GRT) were used and measured with TrueBeam TM STx and Surveillance And Measurement (SAM) 940 detector was used for photoneutron emitted by using 3F and 2F. To assess temporal and economical aspect for a patient, total treatment periods and medical fees were estimated. In using 3F beam, total MUs in IMRT plan increased the highest up to 34.0% and in the test of BOT, GRT and photoneutron, the values in SBRT plan decreased the lowest 39.8, 38.6 and 48.1%, respectively. In the temporal and economical aspect, there were no differences between 3F and 2F beam in all of plans and the results showed that 10 days and 169,560 won was lowest in SBRT plan. According as the results, total MUs increased by using 3F beam than 2F beam but BOT, GRT and photoneutron decreased. From above the results, using 3F beam can decrease intra-fraction setup error and risk of radiation-induced secondary malignancy. But, using 3F beam did not make the benefits of temporal and economical aspect for a patient with the radiation therapy
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Energy Technology Data Exchange (ETDEWEB)
Goo, Jang Hyeon; Won, Hui Su; Hong, Joo Wan; Chang, Nam Jun; Park, Jin Hong [Dept. of Radiation Oncology, Seoul national university Bundang hospital, Sungnam (Korea, Republic of)
2014-12-15
The aim of this study was to appraise properties for radiation therapy techniques and effectiveness of time and economy to a patient in the case of applying flattening filter-free (3F) and flattening filter (2F) beam to the radiation therapy. Alderson rando phantom was scanned for computed tomography image. Treatment plans for intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT) and stereotactic body radiation therapy (SBRT) with 3F and 2F beam were designed for prostate cancer. To evaluate the differences between the 3F and 2F beam, total monitor units (MUs), beam on time (BOT) and gantry rotation time (GRT) were used and measured with TrueBeam{sup TM} STx and Surveillance And Measurement (SAM) 940 detector was used for photoneutron emitted by using 3F and 2F. To assess temporal and economical aspect for a patient, total treatment periods and medical fees were estimated. In using 3F beam, total MUs in IMRT plan increased the highest up to 34.0% and in the test of BOT, GRT and photoneutron, the values in SBRT plan decreased the lowest 39.8, 38.6 and 48.1%, respectively. In the temporal and economical aspect, there were no differences between 3F and 2F beam in all of plans and the results showed that 10 days and 169,560 won was lowest in SBRT plan. According as the results, total MUs increased by using 3F beam than 2F beam but BOT, GRT and photoneutron decreased. From above the results, using 3F beam can decrease intra-fraction setup error and risk of radiation-induced secondary malignancy. But, using 3F beam did not make the benefits of temporal and economical aspect for a patient with the radiation therapy.
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International Nuclear Information System (INIS)
Gunther, Jillian R.; Sato, Mariko; Chintagumpala, Murali; Ketonen, Leena; Jones, Jeremy Y.; Allen, Pamela K.; Paulino, Arnold C.; Okcu, M. Fatih; Su, Jack M.; Weinberg, Jeffrey; Boehling, Nicholas S.; Khatua, Soumen; Adesina, Adekunle; Dauser, Robert; Whitehead, William E.; Mahajan, Anita
2015-01-01
Purpose: The clinical significance of magnetic resonance imaging (MRI) changes after radiation therapy (RT) in children with ependymoma is not well defined. We compared imaging changes following proton beam radiation therapy (PBRT) to those after photon-based intensity modulated RT (IMRT). Methods and Materials: Seventy-two patients with nonmetastatic intracranial ependymoma who received postoperative RT (37 PBRT, 35 IMRT) were analyzed retrospectively. MRI images were reviewed by 2 neuroradiologists. Results: Sixteen PBRT patients (43%) developed postradiation MRI changes at 3.8 months (median) with resolution by 6.1 months. Six IMRT patients (17%) developed changes at 5.3 months (median) with 8.3 months to resolution. Mean age at radiation was 4.4 and 6.9 years for PBRT and IMRT, respectively (P=.06). Age at diagnosis (>3 years) and time of radiation (≥3 years) was associated with fewer imaging changes on univariate analysis (odds ratio [OR]: 0.35, P=.048; OR: 0.36, P=.05). PBRT (compared to IMRT) was associated with more frequent imaging changes, both on univariate (OR: 3.68, P=.019) and multivariate (OR: 3.89, P=.024) analyses. Seven (3 IMRT, 4 PBRT) of 22 patients with changes had symptoms requiring intervention. Most patients were treated with steroids; some PBRT patients also received bevacizumab and hyperbaric oxygen therapy. None of the IMRT patients had lasting deficits, but 2 patients died from recurrent disease. Three PBRT patients had persistent neurological deficits, and 1 child died secondarily to complications from radiation necrosis. Conclusions: Postradiation MRI changes are more common with PBRT and in patients less than 3 years of age at diagnosis and treatment. It is difficult to predict causes for development of imaging changes that progress to clinical significance. These changes are usually self-limiting, but some require medical intervention, especially those involving the brainstem
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Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham
2013-01-01
Introduction Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation ...
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Eftekhari, Mohammad; Anbiaei, Robabeh; Zamani, Hanie; Fallahi, Babak; Beiki, Davood; Ameri, Ahmad; Emami-Ardekani, Alireza; Fard-Esfahani, Armaghan; Gholamrezanezhad, Ali; Seid Ratki, Kazem Razavi; Roknabadi, Alireza Momen
2015-01-01
Radiation therapy for breast cancer can induce myocardial capillary injury and increase cardiovascular morbidity and mortality. A prospective cohort was conducted to study the prevalence of myocardial perfusion abnormalities following radiation therapy of left-sided breast cancer patients as compared to those with right-sided cancer. To minimize potential confounding factors, only those patients with low 10-year risk of coronary artery disease (based on Framingham risk scoring) were included. All patients were initially treated by modified radical mastectomy and then were managed by postoperative 3D Conformal Radiation Therapy (CRT) to the surgical bed with an additional 1-cm margin, delivered by 46-50 Gy (in 2 Gy daily fractions) over a 5-week course. The same dose-adjusted chemotherapy regimen (including anthracyclines, cyclophosphamide and taxol) was given to all patients. Six months after radiation therapy, all patients underwent cardiac SPECT for the evaluation of myocardial perfusion. A total of 71 patients with a mean age of 45.3±7.2 years [35 patients with leftsided breast cancer (exposed) and 36 patients with right-sided cancer (controls)] were enrolled. Dose-volume histogram (DVH) [showing the percentage of the heart exposed to >50% of radiation] was significantly higher in patients with left-sided breast cancer. Visual interpretation detected perfusion abnormalities in 42.9% of cases and 16.7% of controls (P=0.02, Odds ratio=1.46). In semiquantitative segmental analysis, only apical (28.6% versus 8.3%, P=0.03) and anterolateral (17.1% versus 2.8%, P=0.049) walls showed significantly reduced myocardial perfusion in the exposed group. Summed Stress Score (SSS) of>3 was observed in twelve cases (34.3%), while in five of the controls (13.9%),(Odds ratio=1.3). There was no significant difference between the groups regarding left ventricular ejection fraction. The risk of radiation induced myocardial perfusion abnormality in patients treated with CRT on the
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Patterns of clinical care in radiation therapy in the United States
International Nuclear Information System (INIS)
Kramer, S.
1984-01-01
Results of the first nationwide evaluation of radiation therapy in the United States with respect to its quality and accessibility are presented. The Patterns of Care Study (PCS) is financially supported by the National Cancer Institute and has served as a model for other oncology-related disciplines. The PCS has determined criteria by which to evaluate radiation therapy care in 10 disease sites in which curative radiation therapy plays a major role. The sampling design identified the institution to be surveyed and included all types of practice in the U.S. This paper examines results related to carcinomas of the cervix, larynx and prostate
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Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham
2013-01-01
Introduction Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. Methods A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. Results The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. Conclusion The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques. PMID:26229623
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International Nuclear Information System (INIS)
Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham
2013-01-01
Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques
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Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham
2013-12-01
Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147-53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose-volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques.
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Energy Technology Data Exchange (ETDEWEB)
Sale, Charlotte; Moloney, Phillip; Mathlum, Maitham [Andrew Love Cancer Centre, Geelong Hospital, Geelong, Victoria (Australia)
2013-12-15
Patients with anal canal carcinoma treated with standard conformal radiotherapy frequently experience severe acute and late toxicity reactions to the treatment area. Roohipour et al. (Dis Colon Rectum 2008; 51: 147–53) stated a patient's tolerance of chemoradiation to be an important prediction of treatment success. A new intensity modulated radiation therapy (IMRT) technique for anal carcinoma cases has been developed at the Andrew Love Cancer Centre aimed at reducing radiation to surrounding healthy tissue. A same-subject repeated measures design was used for this study, where five anal carcinoma cases at the Andrew Love Cancer Centre were selected. Conformal and IMRT plans were generated and dosimetric evaluations were performed. Each plan was prescribed a total of 54 Gray (Gy) over a course of 30 fractions to the primary site. The IMRT plans resulted in improved dosimetry to the planning target volume (PTV) and reduction in radiation to the critical structures (bladder, external genitalia and femoral heads). Statistically there was no difference between the IMRT and conformal plans in the dose to the small and large bowel; however, the bowel IMRT dose–volume histogram (DVH) doses were consistently lower. The IMRT plans were superior to the conformal plans with improved dose conformity and reduced radiation to the surrounding healthy tissue. Anecdotally it was found that patients tolerated the IMRT treatment better than the three-dimensional (3D) conformal radiation therapy. This study describes and compares the planning techniques.
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International Nuclear Information System (INIS)
Ahunbay, Ergun E.; Kimura, Brad; Liu, Feng; Erickson, Beth A.; Li, X. Allen
2013-01-01
Purpose: To identify practical techniques to address the large interfractional variations for pancreas irradiation by comparing various used/proposed online strategies. Methods and Materials: The daily computed tomography (CT) images acquired using a respiration-gated in-room CT (CTVision; Siemens) for 10 pancreatic cancer patients treated with image guided radiation therapy (IGRT) were analyzed. The contours of the pancreas and organs at risk on each daily CT set were generated by populating from the planning CT using a deformable registration tool (ABAS; Elekta) with manual editing. Nine online strategies were considered: (1) standard IGRT (ie, IGRT with 0-mm additional margin [AM]); (2) IGRT with 2-mm AM; (3) IGRT with 5-mm AM; (4) IGRT with plan renormalized to maintain 95% planning target volume (PTV) coverage; (5) full-scale reoptimization; (6) reoptimization starting from the original plan; (7) segment aperture morphing (SAM) from the original plan, based on PTV shape change; (8) SAM plus segment weight optimization; and (9) reoptimization starting from the SAM plan. One-way analysis of variance was applied to plan qualities for the 9 strategies to assess statistical significance in difference. Results: The 3 IGRT strategies (1-3) lead to either inadequate PTV coverage or higher doses to critical structures, indicating that the additional margins alone are not adequate to account for the changes. The full-scale reoptimization results in the best plan but requires the delineation of several structures, which is time consuming. The SAM strategy (7) was the fastest one, because it requires delineating only 1 structure (target), and its plan quality was comparable to that for the full-scale reoptimization. Conclusion: Online replanning strategies can lead to either reduced organs-at-risk dose and/or improved target coverage as compared with the current practice of IGRT. The SAM-based online replanning is comparable to full-scale reoptimization and is efficient
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Energy Technology Data Exchange (ETDEWEB)
Ahunbay, Ergun E., E-mail: eahunbay@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Kimura, Brad; Liu, Feng; Erickson, Beth A.; Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States)
2013-08-01
Purpose: To identify practical techniques to address the large interfractional variations for pancreas irradiation by comparing various used/proposed online strategies. Methods and Materials: The daily computed tomography (CT) images acquired using a respiration-gated in-room CT (CTVision; Siemens) for 10 pancreatic cancer patients treated with image guided radiation therapy (IGRT) were analyzed. The contours of the pancreas and organs at risk on each daily CT set were generated by populating from the planning CT using a deformable registration tool (ABAS; Elekta) with manual editing. Nine online strategies were considered: (1) standard IGRT (ie, IGRT with 0-mm additional margin [AM]); (2) IGRT with 2-mm AM; (3) IGRT with 5-mm AM; (4) IGRT with plan renormalized to maintain 95% planning target volume (PTV) coverage; (5) full-scale reoptimization; (6) reoptimization starting from the original plan; (7) segment aperture morphing (SAM) from the original plan, based on PTV shape change; (8) SAM plus segment weight optimization; and (9) reoptimization starting from the SAM plan. One-way analysis of variance was applied to plan qualities for the 9 strategies to assess statistical significance in difference. Results: The 3 IGRT strategies (1-3) lead to either inadequate PTV coverage or higher doses to critical structures, indicating that the additional margins alone are not adequate to account for the changes. The full-scale reoptimization results in the best plan but requires the delineation of several structures, which is time consuming. The SAM strategy (7) was the fastest one, because it requires delineating only 1 structure (target), and its plan quality was comparable to that for the full-scale reoptimization. Conclusion: Online replanning strategies can lead to either reduced organs-at-risk dose and/or improved target coverage as compared with the current practice of IGRT. The SAM-based online replanning is comparable to full-scale reoptimization and is efficient
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Hyperbaric oxygen therapy for the treatment of radiation-induced macular ischemia
Directory of Open Access Journals (Sweden)
Shamim A Haji
2010-05-01
Full Text Available Shamim A Haji1,2, Ronald EP Frenkel1,2,31Eye Research Foundation, Stuart, FL, USA; 2East Florida Eye Institute, Stuart, FL, USA; 3Bascom Palmer Eye Institute, Miami, FL, USAPurpose: To report a case of radiation-induced macular ischemia where vision and macular perfusion improved after hyperbaric oxygen (HBO therapy.Methods: A 62-year-old male patient developed radiation-induced macular ischemia after he was treated with radiation for brain glioma. The patient presented with best spectacle-corrected visual acuity (BSCVA acuity of 20/400 in his right eye. Optical coherence tomography (OCT showed central macular thickness of 468 μm. The patient received focal laser, intravitreal triamcinolone, and HBO therapy.Results: The patient’s vision improved from 20/400 to 20/100 after focal laser and intravitreal triamcinolone. His central macular thickness improved from 468 μm to 132 μm. After receiving HBO therapy, his VA improved to 20/50 and fluorescein angiography showed improvement in macular perfusion.Conclusion: HBO therapy improves macular perfusion in patients with radiation-induced macular ischemia.Keywords: macular ischemia, visual acuity, hyperbaric oxygen therapy, macular perfusion
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Efficacy of six weeks infrared radiation therapy on chronic low back ...
African Journals Online (AJOL)
Background: Infrared radiation therapy is a modality widely used in Physiotherapy for the management of pain. The objective of this study was to determine the efficacy of six weeks infrared radiation therapy on pain intensity and functional disability index in subjects suffering from non- specific low back pain. Methods: The ...
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Development of medical application methods using radiation. Radionuclide therapy
International Nuclear Information System (INIS)
Choi, Chang Woon; Lim, S. M.; Kim, E.H.; Woo, K. S.; Chung, W. S.; Lim, S. J.; Choi, T. H.; Hong, S. W.; Chung, H. Y.; No, W. C.; Oh, B. H.; Hong, H. J.
1999-04-01
In this project, we studied following subjects: 1. development of monoclonal antibodies and radiopharmaceuticals 2. clinical applications of radionuclide therapy 3. radioimmunoguided surgery 4. prevention of restenosis with intracoronary radiation. The results can be applied for the following objectives: 1) radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial. 2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research. 3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology
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Development of medical application methods using radiation. Radionuclide therapy
Energy Technology Data Exchange (ETDEWEB)
Choi, Chang Woon; Lim, S. M.; Kim, E.H.; Woo, K. S.; Chung, W. S.; Lim, S. J.; Choi, T. H.; Hong, S. W.; Chung, H. Y.; No, W. C. [Korea Atomic Energy Research Institute. Korea Cancer Center Hospital, Seoul, (Korea, Republic of); Oh, B. H. [Seoul National University. Hospital, Seoul (Korea, Republic of); Hong, H. J. [Antibody Engineering Research Unit, Taejon (Korea, Republic of)
1999-04-01
In this project, we studied following subjects: 1. development of monoclonal antibodies and radiopharmaceuticals 2. clinical applications of radionuclide therapy 3. radioimmunoguided surgery 4. prevention of restenosis with intracoronary radiation. The results can be applied for the following objectives: (1) radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial. (2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research. (3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology.
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International Nuclear Information System (INIS)
Okumura, Toshiyuki; Itai, Yuji; Tsuji, Hiroshi
1994-01-01
Radiation hepatitis is clearly demonstrated by noncontrast and contrast enhanced CT following radiotherapy for liver diseases. Radiation hepatitis is dependent on dose distribution and is usually demonstrated as nonsegmental bandlike lesion after photon therapy. We report a case of focused, oval-shaped radiation hepatitis that was induced by photon therapy. The attenuation difference was localized in a high-dose area caused by Bragg-peak proton therapy. 17 refs., 2 figs
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Inadvertent destruction of the spinal cord by radiation therapy
International Nuclear Information System (INIS)
Bhavilai, D.
1974-01-01
A case of radiation myelopathy following cobalt therapy of a carcinoma of the esophagus is presented. A permanent quadriplegia resulted. Radiation myelopathy can result from treatment with x-rays or radioactive cobalt regardless of whether the condition being treated involves the spinal cord. No effective treatment is known. Prevention requires keeping the radiation at low level
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International Nuclear Information System (INIS)
Lee, P.W.H.; Hung, B.K.M.; Woo, E.K.W.; Tai, P.T.H.; Choi, D.T.K.
1989-01-01
Sixteen patients who had a nasopharyngeal carcinoma (NPC) who were treated with radiation therapy were followed up after a median duration of 5.5 years and given a battery of neuropsychological tests. Results were compared with a comparable group of newly diagnosed NPC patients awaiting radiation therapy. The irradiated group was significantly poorer in overall IQ, non-verbal memory recall, and reported a substantially greater number of memory related complaints. These results contrast with the complacent general assumption that radiation therapy has a negligible effect on adult functioning. (author)
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International Nuclear Information System (INIS)
Hindley, Andrew; Zain, Zakiyah; Wood, Lisa; Whitehead, Anne; Sanneh, Alison; Barber, David; Hornsby, Ruth
2014-01-01
Purpose: We wanted to confirm the benefit of mometasone furoate (MF) in preventing acute radiation reactions, as shown in a previous study (Boström et al, Radiother Oncol 2001;59:257-265). Methods and Materials: The study was a double-blind comparison of MF with D (Diprobase), administered daily from the start of radiation therapy for 5 weeks in patients receiving breast radiation therapy, 40 Gy in 2.67-Gy fractions daily over 3 weeks. The primary endpoint was mean modified Radiation Therapy Oncology Group (RTOG) score. Results: Mean RTOG scores were significantly less for MF than for D (P=.046). Maximum RTOG and mean erythema scores were significantly less for MF than for D (P=.018 and P=.012, respectively). The Dermatology Life Quality Index (DLQI) score was significantly less for MF than for D at weeks 4 and 5 when corrected for Hospital Anxiety and Depression (HAD) questionnaire scores. Conclusions: MF cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. For the first time, we have shown a significantly beneficial effect on quality of life using a validated instrument (DLQI), for a topical steroid cream. We believe that application of this cream should be the standard of care where radiation dermatitis is expected
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Energy Technology Data Exchange (ETDEWEB)
Hindley, Andrew, E-mail: andrew.hindley@lthtr.nhs.uk [Rosemere Cancer Centre, Royal Preston Hospital, Preston (United Kingdom); Zain, Zakiyah [College of Arts and Sciences, Universiti Utara Malaysia, Kedah (Malaysia); Wood, Lisa [Department of Social Sciences, Lancaster Medical School, Lancaster (United Kingdom); Whitehead, Anne [Medical and Pharmaceutical Statistics Research Unit, Lancaster University, Lancaster (United Kingdom); Sanneh, Alison; Barber, David; Hornsby, Ruth [Rosemere Cancer Centre, Royal Preston Hospital, Preston (United Kingdom)
2014-11-15
Purpose: We wanted to confirm the benefit of mometasone furoate (MF) in preventing acute radiation reactions, as shown in a previous study (Boström et al, Radiother Oncol 2001;59:257-265). Methods and Materials: The study was a double-blind comparison of MF with D (Diprobase), administered daily from the start of radiation therapy for 5 weeks in patients receiving breast radiation therapy, 40 Gy in 2.67-Gy fractions daily over 3 weeks. The primary endpoint was mean modified Radiation Therapy Oncology Group (RTOG) score. Results: Mean RTOG scores were significantly less for MF than for D (P=.046). Maximum RTOG and mean erythema scores were significantly less for MF than for D (P=.018 and P=.012, respectively). The Dermatology Life Quality Index (DLQI) score was significantly less for MF than for D at weeks 4 and 5 when corrected for Hospital Anxiety and Depression (HAD) questionnaire scores. Conclusions: MF cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. For the first time, we have shown a significantly beneficial effect on quality of life using a validated instrument (DLQI), for a topical steroid cream. We believe that application of this cream should be the standard of care where radiation dermatitis is expected.
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Tracheoinnominate artery fistula as a complication of radiation therapy
International Nuclear Information System (INIS)
Reiter, D.; Piccone, B.R.; Littman, P.; Lisker, S.A.
1979-01-01
Tracheoinnominate artery fistulization is a well-known complication of tracheostomy and of tracheal resection. The first known occurrence of this problem in a patient in whom no transtracheal procedure had ever been performed is reported, and high-dose radiation therapy delivered three years before for a mediastinal malignancy is suggested as the cause. No evidence of tumor was found in or adjacent to the tracheovascular communication. The tracheoinnominate artery fistula must be considered a potential complication of radiation therapy as well as of surgery
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Decision regret in men undergoing dose-escalated radiation therapy for prostate cancer.
Steer, Anna N; Aherne, Noel J; Gorzynska, Karen; Hoffman, Matthew; Last, Andrew; Hill, Jacques; Shakespeare, Thomas P
2013-07-15
Decision regret (DR) is a negative emotion associated with medical treatment decisions, and it is an important patient-centered outcome after therapy for localized prostate cancer. DR has been found to occur in up to 53% of patients treated for localized prostate cancer, and it may vary depending on treatment modality. DR after modern dose-escalated radiation therapy (DE-RT) has not been investigated previously, to our knowledge. Our primary aim was to evaluate DR in a cohort of patients treated with DE-RT. We surveyed 257 consecutive patients with localized prostate cancer who had previously received DE-RT, by means of a validated questionnaire. There were 220 responses (85.6% response rate). Image-guided intensity modulated radiation therapy was given in 85.0% of patients and 3-dimensional conformal radiation therapy in 15.0%. Doses received included 73.8 Gy (34.5% patients), 74 Gy (53.6%), and 76 Gy (10.9%). Neoadjuvant androgen deprivation (AD) was given in 51.8% of patients and both neoadjuvant and adjuvant AD in 34.5%. The median follow-up time was 23 months (range, 12-67 months). In all, 3.8% of patients expressed DR for their choice of treatment. When asked whether they would choose DE-RT or AD again, only 0.5% probably or definitely would not choose DE-RT again, compared with 8.4% for AD (P<.01). Few patients treated with modern DE-RT express DR, with regret appearing to be lower than in previously published reports of patients treated with radical prostatectomy or older radiation therapy techniques. Patients experienced more regret with the AD component of treatment than with the radiation therapy component, with implications for informed consent. Further research should investigate regret associated with individual components of modern therapy, including AD, radiation therapy and surgery. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.
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Decision Regret in Men Undergoing Dose-Escalated Radiation Therapy for Prostate Cancer
International Nuclear Information System (INIS)
Steer, Anna N.; Aherne, Noel J.; Gorzynska, Karen; Hoffman, Matthew; Last, Andrew; Hill, Jacques; Shakespeare, Thomas P.
2013-01-01
Purpose: Decision regret (DR) is a negative emotion associated with medical treatment decisions, and it is an important patient-centered outcome after therapy for localized prostate cancer. DR has been found to occur in up to 53% of patients treated for localized prostate cancer, and it may vary depending on treatment modality. DR after modern dose-escalated radiation therapy (DE-RT) has not been investigated previously, to our knowledge. Our primary aim was to evaluate DR in a cohort of patients treated with DE-RT. Methods and Materials: We surveyed 257 consecutive patients with localized prostate cancer who had previously received DE-RT, by means of a validated questionnaire. Results: There were 220 responses (85.6% response rate). Image-guided intensity modulated radiation therapy was given in 85.0% of patients and 3-dimensional conformal radiation therapy in 15.0%. Doses received included 73.8 Gy (34.5% patients), 74 Gy (53.6%), and 76 Gy (10.9%). Neoadjuvant androgen deprivation (AD) was given in 51.8% of patients and both neoadjuvant and adjuvant AD in 34.5%. The median follow-up time was 23 months (range, 12-67 months). In all, 3.8% of patients expressed DR for their choice of treatment. When asked whether they would choose DE-RT or AD again, only 0.5% probably or definitely would not choose DE-RT again, compared with 8.4% for AD (P<.01). Conclusion: Few patients treated with modern DE-RT express DR, with regret appearing to be lower than in previously published reports of patients treated with radical prostatectomy or older radiation therapy techniques. Patients experienced more regret with the AD component of treatment than with the radiation therapy component, with implications for informed consent. Further research should investigate regret associated with individual components of modern therapy, including AD, radiation therapy and surgery
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Decision Regret in Men Undergoing Dose-Escalated Radiation Therapy for Prostate Cancer
Energy Technology Data Exchange (ETDEWEB)
Steer, Anna N. [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Aherne, Noel J., E-mail: noel.aherne@ncahs.health.nsw.gov.au [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Rural Clinical School Faculty of Medicine, University of New South Wales, Coffs Harbour (Australia); Gorzynska, Karen; Hoffman, Matthew; Last, Andrew; Hill, Jacques [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Shakespeare, Thomas P. [Department of Radiation Oncology, North Coast Cancer Institute, Coffs Harbour (Australia); Rural Clinical School Faculty of Medicine, University of New South Wales, Coffs Harbour (Australia)
2013-07-15
Purpose: Decision regret (DR) is a negative emotion associated with medical treatment decisions, and it is an important patient-centered outcome after therapy for localized prostate cancer. DR has been found to occur in up to 53% of patients treated for localized prostate cancer, and it may vary depending on treatment modality. DR after modern dose-escalated radiation therapy (DE-RT) has not been investigated previously, to our knowledge. Our primary aim was to evaluate DR in a cohort of patients treated with DE-RT. Methods and Materials: We surveyed 257 consecutive patients with localized prostate cancer who had previously received DE-RT, by means of a validated questionnaire. Results: There were 220 responses (85.6% response rate). Image-guided intensity modulated radiation therapy was given in 85.0% of patients and 3-dimensional conformal radiation therapy in 15.0%. Doses received included 73.8 Gy (34.5% patients), 74 Gy (53.6%), and 76 Gy (10.9%). Neoadjuvant androgen deprivation (AD) was given in 51.8% of patients and both neoadjuvant and adjuvant AD in 34.5%. The median follow-up time was 23 months (range, 12-67 months). In all, 3.8% of patients expressed DR for their choice of treatment. When asked whether they would choose DE-RT or AD again, only 0.5% probably or definitely would not choose DE-RT again, compared with 8.4% for AD (P<.01). Conclusion: Few patients treated with modern DE-RT express DR, with regret appearing to be lower than in previously published reports of patients treated with radical prostatectomy or older radiation therapy techniques. Patients experienced more regret with the AD component of treatment than with the radiation therapy component, with implications for informed consent. Further research should investigate regret associated with individual components of modern therapy, including AD, radiation therapy and surgery.
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Conservative treatment of rectal cancer with local excision and postoperative radiation therapy
International Nuclear Information System (INIS)
Minsky, B.D.
1995-01-01
The conventional surgical treatment for patients with potentially curable transmural and/or node positive rectal cancer is a low anterior resection or abdominoperineal resection. Recently, there has been increasing interest in the use of local excision and postoperative radiation therapy as primary therapy for selected rectal cancers. The limited data suggest that the approach of local excision and postoperative radiation therapy should be limited to patients with either T 1 tumours with adverse pathological factors or T 2 tumours. Transmural tumours, which have a 24% local failure rate, are treated more effectively with standard surgery and pre- or postoperative therapy. The results of local excision and postoperative radiation therapy are encouraging, but more experience is needed to determine if this approach ultimately has similar local control and survival rates as standard surgery. (author)
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International Nuclear Information System (INIS)
Ng, Sook Kien; Zygmanski, Piotr; Lyatskaya, Yulia; D’Amico, Anthony V.; Cormack, Robert A.
2012-01-01
Purpose: To assess the feasibility of using cone-beam tomosynthesis (CBTS) to localize the air–tissue interface for the application of prostate image-guided radiation therapy using an endorectal balloon for immobilization and localization. Methods and Materials: A Feldkamp-David-Kress-based CBTS reconstruction was applied to selected sets of cone-beam computed tomography (CBCT) projection data to simulate volumetric imaging achievable from tomosynthesis for a limited range of scan angles. Projection data were calculated from planning CT images of 10 prostate cancer patients treated with an endorectal balloon, as were experimental CBCT projections for a pelvic phantom in two patients. More than 50 points at the air–tissue interface were objectively identified by an intensity-based interface-finding algorithm. Using three-dimensional point sets extracted from CBTS images compared with points extracted from corresponding CBCT images, the relative shift resulting from a reduced scan angle was determined. Because the CBCT and CBTS images were generated from the same projection data set, shift identified was presumed to be due to distortions introduced by the tomosynthesis technique. Results: Scans of ≥60° were shown to be able to localize an air–tissue interface near the isocenter with accuracy on the order of a millimeter. The accuracy was quantified in terms of the mean discrepancy as a function of reconstruction angle. Conclusion: This work provides an understanding of the effect of scan angle used in localization of a portion of an endorectal balloon by means of CBTS. CBTS with relatively small scan angles is capable of accurately localizing an extended interface near the isocenter and may provide clinically relevant measurements to guide IGRT treatments while reducing imaging radiation to the patient.
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Energy Technology Data Exchange (ETDEWEB)
Ng, Sook Kien, E-mail: Sook_Ng@dfci.harvard.edu [Department of Radiation Oncology, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA (United States); Department of Radiation Oncology, Mannheim Medical Centre, University of Heidelberg, Mannheim (Germany); Zygmanski, Piotr; Lyatskaya, Yulia; D' Amico, Anthony V.; Cormack, Robert A. [Department of Radiation Oncology, Brigham and Women' s Hospital and Harvard Medical School, Boston, MA (United States)
2012-06-01
Purpose: To assess the feasibility of using cone-beam tomosynthesis (CBTS) to localize the air-tissue interface for the application of prostate image-guided radiation therapy using an endorectal balloon for immobilization and localization. Methods and Materials: A Feldkamp-David-Kress-based CBTS reconstruction was applied to selected sets of cone-beam computed tomography (CBCT) projection data to simulate volumetric imaging achievable from tomosynthesis for a limited range of scan angles. Projection data were calculated from planning CT images of 10 prostate cancer patients treated with an endorectal balloon, as were experimental CBCT projections for a pelvic phantom in two patients. More than 50 points at the air-tissue interface were objectively identified by an intensity-based interface-finding algorithm. Using three-dimensional point sets extracted from CBTS images compared with points extracted from corresponding CBCT images, the relative shift resulting from a reduced scan angle was determined. Because the CBCT and CBTS images were generated from the same projection data set, shift identified was presumed to be due to distortions introduced by the tomosynthesis technique. Results: Scans of {>=}60 Degree-Sign were shown to be able to localize an air-tissue interface near the isocenter with accuracy on the order of a millimeter. The accuracy was quantified in terms of the mean discrepancy as a function of reconstruction angle. Conclusion: This work provides an understanding of the effect of scan angle used in localization of a portion of an endorectal balloon by means of CBTS. CBTS with relatively small scan angles is capable of accurately localizing an extended interface near the isocenter and may provide clinically relevant measurements to guide IGRT treatments while reducing imaging radiation to the patient.
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Photoelectric-enhanced radiation therapy with quasi-monochromatic computed tomography.
Jost, Gregor; Mensing, Tristan; Golfier, Sven; Lawaczeck, Rüdiger; Pietsch, Hubertus; Hütter, Joachim; Cibik, Levent; Gerlach, Martin; Krumrey, Michael; Fratzscher, Daniel; Arkadiev, Vladimir; Wedell, Reiner; Haschke, Michael; Langhoff, Norbert; Wust, Peter; Lüdemann, Lutz
2009-06-01
Photoelectric-enhanced radiation therapy is a bimodal therapy, consisting of the administration of highly radiation-absorbing substances into the tumor area and localized regional irradiation with orthovoltage x-rays. Irradiation can be performed by a modified computed tomography (CT) unit equipped with an additional x-ray optical module which converts the polychromatic, fan-shaped CT beam into a monochromatized and focused beam for energy-tuned photoelectric-enhanced radiotherapy. A dedicated x-ray optical module designed for spatial collimation, focusing, and monochromatization was mounted at the exit of the x-ray tube of a clinical CT unit. Spectrally resolved measurements of the resulting beam were performed using an energy-dispersive detection system calibrated by synchrotron radiation. The spatial photon fluence was determined by film dosimetry. Depth-dose measurements were performed and compared to the polychromatic CT and a therapeutic 6 MV beam. The spatial dose distribution in phantoms using a rotating radiation source (quasimonochromatic CT and 6 MV, respectively) was investigated by gel dosimetry. The photoelectric dose enhancement for an iodine fraction of 1% in tissue was calculated and verified experimentally. The x-ray optical module selectively filters the energy of the tungsten Kalpha emission line with an FWHM of 5 keV. The relative photon fluence distribution demonstrates the focusing characteristic of the x-ray optical module. A beam width of about 3 mm was determined at the isocenter of the CT gantry. The depth-dose measurements resulted in a half-depth value of approximately 36 mm for the CT beams (quasi-monochromatic, polychromatic) compared to 154 mm for the 6 MV beam. The rotation of the radiation source leads to a steep dose gradient at the center of rotation; the gel dosimetry yields an entrance-to-peak dose ratio of 1:10.8 for the quasi-monochromatic CT and 1:37.3 for a 6 MV beam of the same size. The photoelectric dose enhancement
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Photoelectric-enhanced radiation therapy with quasi-monochromatic computed tomography
International Nuclear Information System (INIS)
Jost, Gregor; Mensing, Tristan; Golfier, Sven; Lawaczeck, Ruediger; Pietsch, Hubertus; Huetter, Joachim; Cibik, Levent; Gerlach, Martin; Krumrey, Michael; Fratzscher, Daniel; Arkadiev, Vladimir; Wedell, Reiner; Haschke, Michael; Langhoff, Norbert; Wust, Peter; Luedemann, Lutz
2009-01-01
Photoelectric-enhanced radiation therapy is a bimodal therapy, consisting of the administration of highly radiation-absorbing substances into the tumor area and localized regional irradiation with orthovoltage x-rays. Irradiation can be performed by a modified computed tomography (CT) unit equipped with an additional x-ray optical module which converts the polychromatic, fan-shaped CT beam into a monochromatized and focused beam for energy-tuned photoelectric-enhanced radiotherapy. A dedicated x-ray optical module designed for spatial collimation, focusing, and monochromatization was mounted at the exit of the x-ray tube of a clinical CT unit. Spectrally resolved measurements of the resulting beam were performed using an energy-dispersive detection system calibrated by synchrotron radiation. The spatial photon fluence was determined by film dosimetry. Depth-dose measurements were performed and compared to the polychromatic CT and a therapeutic 6 MV beam. The spatial dose distribution in phantoms using a rotating radiation source (quasi-monochromatic CT and 6 MV, respectively) was investigated by gel dosimetry. The photoelectric dose enhancement for an iodine fraction of 1% in tissue was calculated and verified experimentally. The x-ray optical module selectively filters the energy of the tungsten Kα emission line with an FWHM of 5 keV. The relative photon fluence distribution demonstrates the focusing characteristic of the x-ray optical module. A beam width of about 3 mm was determined at the isocenter of the CT gantry. The depth-dose measurements resulted in a half-depth value of approximately 36 mm for the CT beams (quasi-monochromatic, polychromatic) compared to 154 mm for the 6 MV beam. The rotation of the radiation source leads to a steep dose gradient at the center of rotation; the gel dosimetry yields an entrance-to-peak dose ratio of 1:10.8 for the quasi-monochromatic CT and 1:37.3 for a 6 MV beam of the same size. The photoelectric dose enhancement factor
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Photoelectric-enhanced radiation therapy with quasi-monochromatic computed tomography
Energy Technology Data Exchange (ETDEWEB)
Jost, Gregor; Mensing, Tristan; Golfier, Sven; Lawaczeck, Ruediger; Pietsch, Hubertus; Huetter, Joachim; Cibik, Levent; Gerlach, Martin; Krumrey, Michael; Fratzscher, Daniel; Arkadiev, Vladimir; Wedell, Reiner; Haschke, Michael; Langhoff, Norbert; Wust, Peter; Luedemann, Lutz [TRG Diagnostic Imaging, Bayer Schering Pharma AG, 13353 Berlin (Germany); Department of Radiotherapy, Charite Medical Centre, 13353 Berlin (Germany); TRG Diagnostic Imaging, Bayer Schering Pharma AG, 13353 Berlin (Germany); Physikalisch-Technische Bundesanstalt, 10587 Berlin (Germany); Institute of Applied Photonics e.V., 12489 Berlin (Germany); Institute for Scientific Instruments GmbH, 12489 Berlin (Germany); Department of Radiotherapy, Charite Medical Centre, 13353 Berlin (Germany)
2009-06-15
Photoelectric-enhanced radiation therapy is a bimodal therapy, consisting of the administration of highly radiation-absorbing substances into the tumor area and localized regional irradiation with orthovoltage x-rays. Irradiation can be performed by a modified computed tomography (CT) unit equipped with an additional x-ray optical module which converts the polychromatic, fan-shaped CT beam into a monochromatized and focused beam for energy-tuned photoelectric-enhanced radiotherapy. A dedicated x-ray optical module designed for spatial collimation, focusing, and monochromatization was mounted at the exit of the x-ray tube of a clinical CT unit. Spectrally resolved measurements of the resulting beam were performed using an energy-dispersive detection system calibrated by synchrotron radiation. The spatial photon fluence was determined by film dosimetry. Depth-dose measurements were performed and compared to the polychromatic CT and a therapeutic 6 MV beam. The spatial dose distribution in phantoms using a rotating radiation source (quasi-monochromatic CT and 6 MV, respectively) was investigated by gel dosimetry. The photoelectric dose enhancement for an iodine fraction of 1% in tissue was calculated and verified experimentally. The x-ray optical module selectively filters the energy of the tungsten K{alpha} emission line with an FWHM of 5 keV. The relative photon fluence distribution demonstrates the focusing characteristic of the x-ray optical module. A beam width of about 3 mm was determined at the isocenter of the CT gantry. The depth-dose measurements resulted in a half-depth value of approximately 36 mm for the CT beams (quasi-monochromatic, polychromatic) compared to 154 mm for the 6 MV beam. The rotation of the radiation source leads to a steep dose gradient at the center of rotation; the gel dosimetry yields an entrance-to-peak dose ratio of 1:10.8 for the quasi-monochromatic CT and 1:37.3 for a 6 MV beam of the same size. The photoelectric dose enhancement
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Light at the end of the tunnel in radiation therapy: molecular imaging in radiation research
International Nuclear Information System (INIS)
Rao, V.L. Papineni
2013-01-01
Accurate dose delivery to malignant tissue in radiotherapy is quite important for enhancing the treatment efficacy while minimizing morbidity of surrounding normal tissues. Advances in therapeutic strategies and diagnosis technologies along with our understanding of the biology of tumor response to radiation therapy have paved way to allow nearly 60% of current cancer patients to be treated with Radiation Therapy. The confluence of molecular imaging and nanotechnology fields are bridging physics and medicine and are quickly making strides in opening new avenues and therapeutic strategies that complement radiation therapy - with a distinct footprint in immunotherapy, adoptive cell therapy, and targeted chemotherapy. Incorporating optical imaging in radiation therapy in my laboratory, we demonstrated that molecular probes can monitor radiation-induced physiological changes at the target and off-target sites using in vivo molecular imaging approaches. Further we show endogenous bioluminescence resulting from whole body irradiation, which is distinct from the Cherenkov radiation. Mice without anesthesia were held in ventilated mouse pie cage and subjected to 5 Gy X-ray irradiation using commercially available X-RAD320 irradiator (1 Gy/min; F2 beam hardening filter 1.5 mm Al, 0.25 mm Cu, 0.75 mm Sn,). The endogenous bioluminescence from the subjects was captured using cooled CCD camera. Significant increase (up to 100 fold) in the amounts of photons released as bioluminescence was detected during 5 min capture from the mice subjected to irradiation compared to that of the control. To determine the early inflammatory response, the reactive oxygen species (ROS) activity was monitored using L-012 (8-amino-5-chloro-7-phenylpyridol (3,4-d)pyridazine-1,4(2H,3H) dione), a chemiluminescence reporter. L-012 was administered (i.p) after 15 min of irradiation. Chemiluminescence resulting from the irradiation induced ROS activity, possible through the action of the
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Radiation therapy: model standards for determination of need
International Nuclear Information System (INIS)
Lagasse, L.G.; Devins, T.B.
1982-03-01
Contents: Health planning process; Health care requirements (model for projecting need for megavoltage radiation therapy); Operational objectives (manpower, megavoltage therapy and treatment planning equipment, support services, management and evaluation of patient care, organization and administration); Compliance with other standards imposed by law; Financial feasibility and capability; Reasonableness of expenditures and costs; Relative merit; Environmental impact
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Role of Definitive Radiation Therapy in Carcinoma of Unknown Primary in the Abdomen and Pelvis
International Nuclear Information System (INIS)
Kelly, Patrick; Das, Prajnan; Varadhachary, Gauri R.; Fontanilla, Hiral P.; Krishnan, Sunil; Delclos, Marc E.; Jhingran, Anuja; Eifel, Patricia J.; Crane, Christopher H.
2012-01-01
Objectives: Carcinoma of unknown primary (CUP) in the abdomen and pelvis is a heterogeneous group of cancers with no standard treatment. Considered by many to be incurable, these patients are often treated with chemotherapy alone. In this study, we determined the effectiveness of radiation therapy in combination with chemotherapy in patients with CUP in the abdomen and pelvis. Patients and Methods: Medical records were reviewed for 37 patients with CUP treated with radiation therapy for disease located in the soft tissues and/or nodal basins of the abdomen and pelvis at University of Texas M.D. Anderson Cancer between 2002 and 2009. All patients underwent chemotherapy, either before or concurrent with radiation therapy. Patients were selected for radiation therapy on the basis of histologic type, disease extent, and prior therapy response. Twenty patients underwent definitive radiation therapy (defined as radiation therapy targeting all known disease sites with at least 45 Gy) and 17 patients underwent palliative radiation therapy. Only 6 patients had surgical resection of their disease. Patient and treatment characteristics were extracted and the endpoints of local disease control, progression-free survival (PFS), overall survival (OS), and treatment-related toxicity incidence were analyzed. Results: The 2-year PFS and OS rates for the entire cohort were 32% and 57%, respectively. However, in patients treated with definitive radiation therapy, the rates were 48% and 76%, and 7 patients lived more than 3 years after treatment with no evidence of disease progression. Nevertheless, radiation-associated toxicity was significant in this cohort, as 40% experienced Grade 2 or higher late toxicities. Conclusions: The use of definitive radiation therapy should be considered in selected patients with CUP in the soft tissues or nodal basins of the abdomen and pelvis.
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International Nuclear Information System (INIS)
Okamoto, Isaku; Ito, Hiroyuki; Shimizu, Akira; Shimizu, Shigetaka; Suzuki, Mamoru; Yoshida, Tomoyuki; Nakamura, Kazuhiro; Tsukahara, Kiyoaki
2010-01-01
The data of 14 patients with squamous cell carcinoma of the maxillary sinus who were admitted to our hospital and received radiation therapy and concurrent superselective intraarterial infusion therapy between 1998 and 2008 were analyzed to determine the effect of the primary treatment and the adverse events. The subjects were between 43 and 79 years old (median, 61 years old), and there were 10 male and 4 female patients. Superselective intraarterial infusion therapy was administered using the Seldinger method, and cisplatin (CDDP) was administered by intraarterial infusion at a total of 200 mg/m 2 . 5-fluorouracil (FU) was systemically administered by intravenous infusion at the dose of 800 mg/m 2 from day 2 to day 5. In addition, radiation therapy was given concurrently, beginning on day 2. At 4 weeks after completion of the scheduled radiation therapy combined with superselective intraarterial infusion therapy, the treatment effect was judged based on macroscopic, radiological and histopathological findings. The response rates to the primary treatment were as follows: 57.1%, complete response (CR) (8 patients) and 42.9%, partial response (PR) (6 patients). Thus, the overall response rate was 100%. As for the adverse events, while grade 4 cerebral infarction occurred in one patient, all of the other adverse events were reversible and not serious. The safety of the treatment was therefore considered to be acceptable. We are planning to investigate the long-term outcomes in a future study. (author)
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The new radiation protection ordinance and its consequences in radiation therapy
International Nuclear Information System (INIS)
Wucherer, M.; Schmidt, T.
2002-01-01
The new radiation protection ordinance (StrlSchV) entails a number of additional or changed instructions. They require that personnel exposed to radiation at work be reclassified, or that personnel not exposed to radiation at work be classified as personnel exposed to radiation at work, that local dosage measurements be taken particularly in radiation therapy, in order to insure that the radiation protection areas prevailing to date can be maintained, that generally accessible areas be examined to determine whether with persons not exposed to radiation in the course of work, in the case of their prolonged presence there, 1 mSv per year is not exceeded, that instructions be put in writing, that at regular 5-year intervals the proficiency of physicians, specialists in medical physics and MTRAs be brought up to date and, that medical positions for radiooncologists be established. The stricter requirements in radiation protection are inevitably connected with greater expenditures and higher costs. These results of the new radiation protection ordinance are in direct opposition to the financial possibilities that are being restricted through budgeting and pressure on hospitals and practices to reduce costs. (orig.) [de
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The role of radiation therapy in malignant pleural mesothelioma: A systematic review
International Nuclear Information System (INIS)
Ung, Yee C.; Yu, Edward; Falkson, Conrad; Haynes, Adam E.; Stys-Norman, Denise; Evans, William K.
2006-01-01
Introduction: Radiation therapy may offer patients presenting with malignant pleural mesothelioma (MPM) symptom palliation and improvements in quality of life. This systematic review will address the role of radiation therapy in the management of MPM. Methods: A thorough systematic search of the literature was conducted for published articles and conference proceedings for applicable abstracts. Relevant trials were selected and assessed. Results: Three small randomized controlled trials compared prophylactic external beam radiation therapy to no radiation therapy for patients with thoracic tracts caused by drainage tubes or diagnostic procedures. None of those trials reported any serious adverse effects. A pooled analysis found no significant reduction in the frequency of procedure tract metastases. Four non-comparative studies have shown that hemithoracic irradiation alone resulted in significant toxicity, including radiation-induced pulmonary fibrosis, radiation pneumonitis, and bronchopleural fistula, without any survival benefit. Few of the identified studies reported on symptom control, and no studies included formal measures of quality of life. Conclusion: There is limited evidence for the role of radiotherapy in the management of patients with MPM. Future studies including radiotherapy for the treatment of such patients should include formal measures of quality of life and symptom control
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Radical radiation therapy for prostate cancer in Japan. A patterns of care study report
International Nuclear Information System (INIS)
Nakamura, Katsumasa; Mitsuhashi, Norio
2003-01-01
The patterns of radical radiation therapy for prostate cancer are unclear in Japan. A Patterns of Care Study was performed throughout Japan to examine the patterns of radiation therapy for prostate cancer. From 1999 to 2000, extramural audits were performed on 50 randomly selected institutions (∼7% of all institutions in Japan). Detailed information was collected on a total of 311 prostate cancer patients without evidence of distant metastases, who were treated by radiation therapy between 1996 and 1998. Of these 311 patients, 162 treated radically using photon beams were analyzed in this study. Eighty percent of the patients had high-risk diseases defined as T3 or T4 tumors, a pretreatment prostate-specific antigen level >20 ng/ml or poorly differentiated adenocarcinoma. Androgen ablation was performed in 85.8% of patients and the median duration of hormonal therapy before and after radiation therapy was 5.3 and 21.4 months, respectively. The median total dose of radiation therapy to the prostate was 65.0 Gy (range: 20-74 Gy). The 3-year overall and biochemical relapse-free survival rates were 86.7 and 86.1%, respectively. Late toxicity was mild, with only nine patients (5.6%) exhibiting grade 2 late morbidity. The majority of the patients who received radical radiation therapy in Japan have high-risk disease. Androgen ablation plus radiation therapy was commonly used to treat these patients and resulted in high rates of initial control with a low risk of complications. (author)
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Adjuvant radiation therapy for pancreatic cancer: a 15-year experience
International Nuclear Information System (INIS)
Dobelbower, Ralph R.; Merrick, Hollis W.; Khuder, Sadik; Battle, Joyce A.; Herron, Lisa M.; Pawlicki, Todd
1997-01-01
Purpose: A retrospective analysis to determine differences in survival of patients with pancreatic aden carcinoma treated by radical surgery with and without adjuvant radiation therapy. Methods and Materials: Between 1980 and 1995, 249 patients with pancreatic tumors were identified at the Medical College of Ohio. Forty-four of these patients underwent radical surgical procedures with curative intent. These patients were divided into four groups according to treatment: surgery alone (n = 14), surgery plus intraoperative radiation therapy (IORT) (n = 6), surgery plus external beam radiation therapy (EBRT) (n = 14), or surgery plus both IORT and EBRT (n = 10). Outcome and survival were analyzed among the four groups. Results: The median survival time of patients treated with radical surgery alone was 6.5 months. The median survival time for the surgery plus IORT group was 9 months; however, 33.3% (two of six) of these patients survived longer than 5 years. This survival pattern was borderline significantly better than that for the surgery alone group (p = 0.0765). The surgery plus EBRT and the surgery plus IORT and EBRT groups had median survival times of 14.5 and 17.5 months, respectively. These were significantly better than that of the surgery alone group (p = 0.0004 and p = 0.0002, respectively). The addition of radiation therapy did not affect the treatment complication rate. Conclusion: The survival of patients who were treated with radical surgery alone was significantly poorer than that of patients who received adjuvant radiation therapy. These results are consistent with other studies in the literature. Patients treated with all three modalities (surgery, IORT, and EBRT) displayed the best median survival time
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Guidelines for respiratory motion management in radiation therapy
International Nuclear Information System (INIS)
Matsuo, Yukinori; Onishi, Hiroshi; Nakagawa, Keiichi
2013-01-01
Respiratory motion management (RMM) systems in external and stereotactic radiotherapies have been developed in the past two decades. Japanese medical service fee regulations introduced reimbursement for RMM from April 2012. Based on thorough discussions among the four academic societies concerned, these Guidelines have been developed to enable staff (radiation oncologists, radiological technologists, medical physicists, radiotherapy quality managers, radiation oncology nurses, and others) to apply RMM to radiation therapy for tumors subject to respiratory motion, safely and appropriately. (author)
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Radiation therapy of gynecological cancer
International Nuclear Information System (INIS)
Nori, D.; Hilaris, B.S.
1987-01-01
This book consists of three parts: General Principles; Clinical Applications; and Special Topics. Some of the papers are: Introduction to Basic Radiobiology; Staging and Work-up Procedures for Patients with Gynecological Cancers; Radiation Therapy in the Treatment of Cancer of the Cervix; Role of Interstitial Implantation in Gynecological Cancer; Role of Radiocolloids in Gynecological Cancer; Radiosensitizers and Protectors; and Management of Lymphoma Associated with Pregnancy
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Quasi-VMAT in high-grade glioma radiation therapy
International Nuclear Information System (INIS)
Fadda, G.; Massazza, G.; Zucca, S.; Durzu, S.; Meleddu, G.; Possanzini, M.; Farace, P.
2013-01-01
Purpose: To compare a quasi-volumetric modulated arc therapy (qVMAT) with three-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) for the treatment of high-grade gliomas. The qVMAT technique is a fast method of radiation therapy in which multiple equispaced beams analogous to those in rotation therapy are radiated in succession. Patients and methods: This study included 12 patients with a planning target volume (PTV) that overlapped at least one organ at risk (OAR). 3D-CRT was planned using 2-3 non-coplanar beams, whereby the field-in-field technique (FIF) was used to divide each field into 1-3 subfields to shield the OAR. The qVMAT strategy was planned with 15 equispaced beams and IMRT was planned using 9 beams with a total of 80 segments. Inverse planning for qVMAT and IMRT was performed by direct machine parameter optimization (DMPO) to deliver a homogenous dose distribution of 60 Gy within the PTV and simultaneously limit the dose received by the OARs to the recommended values. Finally, the effect of introducing a maximum dose objective (max. dose 95% and conformity index (CI) values in comparison to 3D-CRT (PTV 95% = 90.7 % vs. 82.0 %; CI = 0.79 vs. 0.74, respectively). A further improvement was achieved by IMRT (PTV 95% = 94.4 %, CI = 0.78). In qVMAT and IMRT, the addition of a 0.5 cm ring around the PTV produced a significant increase in CI (0.87 and 0.88, respectively), but dosage homogeneity within the PTV was considerably reduced (PTV 95% = 88.5 % and 92.3 %, respectively). The time required for qVMAT dose delivery was similar to that required using 3D-CRT. Conclusion: These findings suggest that qVMAT should be preferred to 3D-CRT for the treatment of high-grade gliomas. The qVMAT method could be applied in hospitals, for example, which have limited departmental resources and are not equipped with systems capable of VMAT delivery. (orig.)
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Treatment of Head and Neck Paragangliomas With External Beam Radiation Therapy
Energy Technology Data Exchange (ETDEWEB)
Dupin, Charles, E-mail: c.dupin@bordeaux.unicancer.fr [Department of Radiotherapy, Comprehensive Cancer Center, Institut Bergonié, Bordeaux (France); Lang, Philippe [Department of Radiotherapy, Pitié Salpétrière, Paris (France); Dessard-Diana, Bernadette [Department of Radiotherapy, Hopital Européen Georges Pompidou, Paris (France); Simon, Jean-Marc; Cuenca, Xavier; Mazeron, Jean-Jacques; Feuvret, Loïc [Department of Radiotherapy, Pitié Salpétrière, Paris (France)
2014-06-01
Purpose: To retrospectively assess the outcomes of radiation therapy in patients with head and neck paragangliomas. Methods and Materials: From 1990 to 2009, 66 patients with 81 head and neck paragangliomas were treated by conventional external beam radiation therapy in 25 fractions at a median dose of 45 Gy (range, 41.4-68 Gy). One case was malignant. The median gross target volume and planning target volume were 30 cm{sup 3} (range, 0.9-243 cm{sup 3}) and 116 cm{sup 3} (range, 24-731 cm{sup 3}), respectively. Median age was 57.4 years (range, 15-84 years). Eleven patients had multicentric lesions, and 8 had family histories of paraganglioma. Paragangliomas were located in the temporal bone, the carotid body, and the glomus vagal in 51, 18, and 10 patients, respectively. Forty-six patients had exclusive radiation therapy, and 20 had salvage radiation therapy. The median follow-up was 4.1 years (range, 0.1-21.2 years). Results: One patient had a recurrence of temporal bone paraganglioma 8 years after treatment. The actuarial local control rates were 100% at 5 years and 98.7% at 10 years. Patients with multifocal tumors and family histories were significantly younger (42 years vs 58 years [P=.002] and 37 years vs 58 years [P=.0003], respectively). The association between family predisposition and multifocality was significant (P<.001). Two patients had cause-specific death within the 6 months after irradiation. During radiation therapy, 9 patients required hospitalization for weight loss, nausea, mucositis, or ophthalmic zoster. Two late vascular complications occurred (middle cerebral artery and carotid stenosis), and 2 late radiation-related meningiomas appeared 15 and 18 years after treatment. Conclusion: Conventional external beam radiation therapy is an effective and safe treatment option that achieves excellent local control; it should be considered as a first-line treatment of choice for head and neck paragangliomas.
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Normal tissue tolerance to external beam radiation therapy: Brain and hypophysis
International Nuclear Information System (INIS)
Haberer, S.; Assouline, A.; Mazeron, J.J.
2010-01-01
Anticancer treatments-induced central nervous system neurotoxicity has become a major problem in recent years. Real advances in therapeutic results for cancer treatments have improved patients survival. Nowadays, central nervous system radiation therapy is widely prescribed, both for palliative and curative treatments in the management of malignant or benign tumors. Recent data on tolerance of normal central nervous system to radiation therapy are reviewed here, early and delayed radiation-induced effects are described and dose recommendations are suggested for clinical practice. (authors)
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Khan's lectures handbook of the physics of radiation therapy
Khan, Faiz M; Mihailidis, Dimitris
2011-01-01
Khan's Lectures: Handbook of the Physics of Radiation Therapy will provide a digest of the material contained in The Physics of Radiation Therapy. Lectures will be presented somewhat similar to a PowerPoint format, discussing key points of individual chapters. Selected diagrams from the textbook will be used to initiate the discussion. New illustrations will used, wherever needed, to enhance the understanding of important concepts. Discussion will be condensed and often bulleted. Theoretical details will be referred to the textbook and the cited literature. A problem set (practice questions) w
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Use dibunol therapy for radiation injuries of the skin and mucous membranes
Energy Technology Data Exchange (ETDEWEB)
Agafonova, G.B.; Barsel' , V.A.; Sarkisyan, Yu.Kh.; Terekhova, G.S.; Podlyashchuk, E.L.; Ustinova, V.F. (Nauchno-Issledovatel' skij Inst. Rentgenologii i Radiologii, Moscow (USSR); AN SSSR, Moscow. Inst. Khimicheskoj Fiziki)
1983-04-01
There are presented the results of the use of dibunol in the form of liniment (1-10%) for the treatment of radiation cystitis and rectitis resulting from radiation therapy of small pelvic tumors, epidermitis and epithelitis that develop in the course of treatment of skin and lower lip tumors. A high efficacy of the drug in the therapy of radiation injury has been shown in 212 patients.