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Sample records for adaptive radiation therapy

  1. Automatic Organ Localization for Adaptive Radiation Therapy for Prostate Cancer

    National Research Council Canada - National Science Library

    Joshi, Sarang

    2004-01-01

    The focus of this study is adaptive radiation therapy (ART) for prostate cancer, in which the treatment is to be adjusted over time, based on CT images acquired on the treatment table before each daily treatment...

  2. Optimization of adaptive radiation therapy in cervical cancer: Solutions for photon and proton therapy

    NARCIS (Netherlands)

    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

  3. Dosimetrically Triggered Adaptive Intensity Modulated Radiation Therapy for Cervical Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Karen [Department of Radiation Oncology, Liverpool Hospital, Sydney (Australia); Stewart, James [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario (Canada); Kelly, Valerie [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Xie, Jason [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Brock, Kristy K. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Moseley, Joanne [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Cho, Young-Bin; Fyles, Anthony [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Lundin, Anna; Rehbinder, Henrik; Löf, Johan [RaySearch Laboratories AB, Stockholm (Sweden); Jaffray, David A. [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Department of Medical Biophysics, University of Toronto, Toronto, Ontario (Canada); Techna Institute for the Advancement of Technology for Health, Toronto, Ontario (Canada); Milosevic, Michael, E-mail: mike.milosevic@rmp.uhn.ca [Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada)

    2014-09-01

    Purpose: The widespread use of intensity modulated radiation therapy (IMRT) for cervical cancer has been limited by internal target and normal tissue motion. Such motion increases the risk of underdosing the target, especially as planning margins are reduced in an effort to reduce toxicity. This study explored 2 adaptive strategies to mitigate this risk and proposes a new, automated method that minimizes replanning workload. Methods and Materials: Thirty patients with cervical cancer participated in a prospective clinical study and underwent pretreatment and weekly magnetic resonance (MR) scans over a 5-week course of daily external beam radiation therapy. Target volumes and organs at risk (OARs) were contoured on each of the scans. Deformable image registration was used to model the accumulated dose (the real dose delivered to the target and OARs) for 2 adaptive replanning scenarios that assumed a very small PTV margin of only 3 mm to account for setup and internal interfractional motion: (1) a preprogrammed, anatomy-driven midtreatment replan (A-IMRT); and (2) a dosimetry-triggered replan driven by target dose accumulation over time (D-IMRT). Results: Across all 30 patients, clinically relevant target dose thresholds failed for 8 patients (27%) if 3-mm margins were used without replanning. A-IMRT failed in only 3 patients and also yielded an additional small reduction in OAR doses at the cost of 30 replans. D-IMRT assured adequate target coverage in all patients, with only 23 replans in 16 patients. Conclusions: A novel, dosimetry-triggered adaptive IMRT strategy for patients with cervical cancer can minimize the risk of target underdosing in the setting of very small margins and substantial interfractional motion while minimizing programmatic workload and cost.

  4. Adaptive Stereotactic Body Radiation Therapy Planning for Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Yujiao [Medical Physics Graduate Program, Duke University, Durham, North Carolina (United States); Zhang, Fan [Occupational and Environmental Safety Office, Duke University Medical Center, Durham, North Carolina (United States); Yoo, David S.; Kelsey, Chris R. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Yin, Fang-Fang [Medical Physics Graduate Program, Duke University, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Cai, Jing, E-mail: jing.cai@duke.edu [Medical Physics Graduate Program, Duke University, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)

    2013-09-01

    Purpose: To investigate the dosimetric effects of adaptive planning on lung stereotactic body radiation therapy (SBRT). Methods and Materials: Forty of 66 consecutive lung SBRT patients were selected for a retrospective adaptive planning study. CBCT images acquired at each fraction were used for treatment planning. Adaptive plans were created using the same planning parameters as the original CT-based plan, with the goal to achieve comparable comformality index (CI). For each patient, 2 cumulative plans, nonadaptive plan (P{sub NON}) and adaptive plan (P{sub ADP}), were generated and compared for the following organs-at-risks (OARs): cord, esophagus, chest wall, and the lungs. Dosimetric comparison was performed between P{sub NON} and P{sub ADP} for all 40 patients. Correlations were evaluated between changes in dosimetric metrics induced by adaptive planning and potential impacting factors, including tumor-to-OAR distances (d{sub T-OAR}), initial internal target volume (ITV{sub 1}), ITV change (ΔITV), and effective ITV diameter change (Δd{sub ITV}). Results: 34 (85%) patients showed ITV decrease and 6 (15%) patients showed ITV increase throughout the course of lung SBRT. Percentage ITV change ranged from −59.6% to 13.0%, with a mean (±SD) of −21.0% (±21.4%). On average of all patients, P{sub ADP} resulted in significantly (P=0 to .045) lower values for all dosimetric metrics. Δd{sub ITV}/d{sub T-OAR} was found to correlate with changes in dose to 5 cc (ΔD5cc) of esophagus (r=0.61) and dose to 30 cc (ΔD30cc) of chest wall (r=0.81). Stronger correlations between Δd{sub ITV}/d{sub T-OAR} and ΔD30cc of chest wall were discovered for peripheral (r=0.81) and central (r=0.84) tumors, respectively. Conclusions: Dosimetric effects of adaptive lung SBRT planning depend upon target volume changes and tumor-to-OAR distances. Adaptive lung SBRT can potentially reduce dose to adjacent OARs if patients present large tumor volume shrinkage during the treatment.

  5. Radiation Therapy

    Science.gov (United States)

    ... Be extra careful not to spend time with children or pregnant women. Internal Radiation Therapy Makes You Give Off Radiation With systemic radiation, your body fluids ( urine , sweat, and saliva ) will give off radiation for a while. With ...

  6. Radiation Therapy

    Science.gov (United States)

    Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from ... half of all cancer patients receive it. The radiation may be external, from special machines, or internal, ...

  7. Adaptive radiation therapy for postprostatectomy patients using real-time electromagnetic target motion tracking during external beam radiation therapy.

    Science.gov (United States)

    Zhu, Mingyao; Bharat, Shyam; Michalski, Jeff M; Gay, Hiram A; Hou, Wei-Hsien; Parikh, Parag J

    2013-03-15

    Using real-time electromagnetic (EM) transponder tracking data recorded by the Calypso 4D Localization System, we report inter- and intrafractional target motion of the prostate bed, describe a strategy to evaluate treatment adequacy in postprostatectomy patients receiving intensity modulated radiation therapy (IMRT), and propose an adaptive workflow. Tracking data recorded by Calypso EM transponders was analyzed for postprostatectomy patients that underwent step-and-shoot IMRT. Rigid target motion parameters during beam delivery were calculated from recorded transponder positions in 16 patients with rigid transponder geometry. The delivered doses to the clinical target volume (CTV) were estimated from the planned dose matrix and the target motion for the first 3, 5, 10, and all fractions. Treatment adequacy was determined by comparing the delivered minimum dose (Dmin) with the planned Dmin to the CTV. Treatments were considered adequate if the delivered CTV Dmin is at least 95% of the planned CTV Dmin. Translational target motion was minimal for all 16 patients (mean: 0.02 cm; range: -0.12 cm to 0.07 cm). Rotational motion was patient-specific, and maximum pitch, yaw, and roll were 12.2, 4.1, and 10.5°, respectively. We observed inadequate treatments in 5 patients. In these treatments, we observed greater target rotations along with large distances between the CTV centroid and transponder centroid. The treatment adequacy from the initial 10 fractions successfully predicted the overall adequacy in 4 of 5 inadequate treatments and 10 of 11 adequate treatments. Target rotational motion could cause underdosage to partial volume of the postprostatectomy targets. Our adaptive treatment strategy is applicable to post-prostatectomy patients receiving IMRT to evaluate and improve radiation therapy delivery. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. [Adaptive radiation therapy for non-small cell lung cancer].

    Science.gov (United States)

    Bibault, J-E; Arsène-Henry, A; Durdux, C; Mornex, F; Hamza, S; Trouette, R; Thureau, S; Faivre, J-C; Boisselier, P; Lerouge, D; Paragios, N; Giraud, P

    2015-10-01

    Anatomical changes and tumor regression during thoracic radiotherapy may alter the treatment volumes. These modifications are not taken into account into set-up or motion margins used for treatment planning. Their dosimetric impact could be significant and a better understanding of the changes occurring during the 6 to 7 weeks of treatment could be useful in order to define quantitative thresholds before a new treatment planning is needed. Margins could also be reduced in order to better spare organs at risk and perform targeted dose escalation. This review assesses the potential of morphologic and metabolic imaging during treatment for adaptive radiotherapy in non-small cell lung cancer. Copyright © 2015 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  9. Adaptive Breast Radiation Therapy Using Modeling of Tissue Mechanics: A Breast Tissue Segmentation Study

    Energy Technology Data Exchange (ETDEWEB)

    Juneja, Prabhjot, E-mail: Prabhjot.Juneja@icr.ac.uk [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom); Harris, Emma J. [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom); Kirby, Anna M. [Department of Academic Radiotherapy, Royal Marsden National Health Service Foundation Trust, Sutton (United Kingdom); Evans, Philip M. [Joint Department of Physics, Institute of Cancer Research, Sutton (United Kingdom)

    2012-11-01

    Purpose: To validate and compare the accuracy of breast tissue segmentation methods applied to computed tomography (CT) scans used for radiation therapy planning and to study the effect of tissue distribution on the segmentation accuracy for the purpose of developing models for use in adaptive breast radiation therapy. Methods and Materials: Twenty-four patients receiving postlumpectomy radiation therapy for breast cancer underwent CT imaging in prone and supine positions. The whole-breast clinical target volume was outlined. Clinical target volumes were segmented into fibroglandular and fatty tissue using the following algorithms: physical density thresholding; interactive thresholding; fuzzy c-means with 3 classes (FCM3) and 4 classes (FCM4); and k-means. The segmentation algorithms were evaluated in 2 stages: first, an approach based on the assumption that the breast composition should be the same in both prone and supine position; and second, comparison of segmentation with tissue outlines from 3 experts using the Dice similarity coefficient (DSC). Breast datasets were grouped into nonsparse and sparse fibroglandular tissue distributions according to expert assessment and used to assess the accuracy of the segmentation methods and the agreement between experts. Results: Prone and supine breast composition analysis showed differences between the methods. Validation against expert outlines found significant differences (P<.001) between FCM3 and FCM4. Fuzzy c-means with 3 classes generated segmentation results (mean DSC = 0.70) closest to the experts' outlines. There was good agreement (mean DSC = 0.85) among experts for breast tissue outlining. Segmentation accuracy and expert agreement was significantly higher (P<.005) in the nonsparse group than in the sparse group. Conclusions: The FCM3 gave the most accurate segmentation of breast tissues on CT data and could therefore be used in adaptive radiation therapy-based on tissue modeling. Breast tissue

  10. Adaptive planning using megavoltage fan-beam CT for radiation therapy with testicular shielding

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Poonam [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); School of Advance Sciences, Vellore Institue of Technology University, Vellore, Tamil Nadu (India); Kozak, Kevin [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Tolakanahalli, Ranjini [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Ramasubramanian, V. [School of Advance Sciences, Vellore Institue of Technology University, Vellore, Tamil Nadu (India); Paliwal, Bhudatt R. [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin, Riverview Cancer Centre, Wisconsin Rapids, WI (United States); Welsh, James S. [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Rong, Yi, E-mail: rong@humonc.wisc.edu [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin, Riverview Cancer Centre, Wisconsin Rapids, WI (United States)

    2012-07-01

    This study highlights the use of adaptive planning to accommodate testicular shielding in helical tomotherapy for malignancies of the proximal thigh. Two cases of young men with large soft tissue sarcomas of the proximal thigh are presented. After multidisciplinary evaluation, preoperative radiation therapy was recommended. Both patients were referred for sperm banking and lead shields were used to minimize testicular dose during radiation therapy. To minimize imaging artifacts, kilovoltage CT (kVCT) treatment planning was conducted without shielding. Generous hypothetical contours were generated on each 'planning scan' to estimate the location of the lead shield and generate a directionally blocked helical tomotherapy plan. To ensure the accuracy of each plan, megavoltage fan-beam CT (MVCT) scans were obtained at the first treatment and adaptive planning was performed to account for lead shield placement. Two important regions of interest in these cases were femurs and femoral heads. During adaptive planning for the first patient, it was observed that the virtual lead shield contour on kVCT planning images was significantly larger than the actual lead shield used for treatment. However, for the second patient, it was noted that the size of the virtual lead shield contoured on the kVCT image was significantly smaller than the actual shield size. Thus, new adaptive plans based on MVCT images were generated and used for treatment. The planning target volume was underdosed up to 2% and had higher maximum doses without adaptive planning. In conclusion, the treatment of the upper thigh, particularly in young men, presents several clinical challenges, including preservation of gonadal function. In such circumstances, adaptive planning using MVCT can ensure accurate dose delivery even in the presence of high-density testicular shields.

  11. A Clinical Concept for Interfractional Adaptive Radiation Therapy in the Treatment of Head and Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Alexandra D., E-mail: Alexandra.Jensen@med.uni-heidelberg.de [Department of Radiation Oncology, University of Heidelberg, Heidelberg (Germany); Nill, Simeon [Department of Medical Physics, German Cancer Research Centre (DKFZ), Heidelberg (Germany); Huber, Peter E. [Clinical Co-Operation Unit Radiation Oncology, German Cancer Research Centre (DKFZ), Heidelberg (Germany); Bendl, Rolf [Department of Medical Physics, German Cancer Research Centre (DKFZ), Heidelberg (Germany); Debus, Juergen; Muenter, Marc W. [Department of Radiation Oncology, University of Heidelberg, Heidelberg (Germany)

    2012-02-01

    Purpose: To present an approach to fast, interfractional adaptive RT in intensity-modulated radiation therapy (IMRT) of head and neck tumors in clinical routine. Ensuring adequate patient position throughout treatment proves challenging in high-precision RT despite elaborate immobilization. Because of weight loss, treatment plans must be adapted to account for requiring supportive therapy incl. feeding tube or parenteral nutrition without treatment breaks. Methods and Materials: In-room CT position checks are used to create adapted IMRT treatment plans by stereotactic correlation to the initial setup, and volumes are adapted to the new geometry. New IMRT treatment plans are prospectively created on the basis of position control scans using the initial optimization parameters in KonRad without requiring complete reoptimization and thus facilitating quick replanning in daily routine. Patients treated for squamous cell head and neck cancer (SCCHN) in 2006-2007 were evaluated as to necessity/number of replannings, weight loss, dose, and plan parameters. Results: Seventy-two patients with SCCHN received IMRT to the primary site and lymph nodes (median dose 70.4 Gy). All patients received concomitant chemotherapy requiring supportive therapy by feeding tube or parenteral nutrition. Median weight loss was 7.8 kg, median volume loss was approximately 7%. Fifteen of 72 patients required adaptation of their treatment plans at least once. Target coverage was improved by up to 10.7% (median dose). The increase of dose to spared parotid without replanning was 11.7%. Replanning including outlining and optimization was feasible within 2 hours for each patient, and treatment could be continued without any interruptions. Conclusion: To preserve high-quality dose application, treatment plans must be adapted to anatomical changes. Replanning based on position control scans therefore presents a practical approach in clinical routine. In the absence of clinically usable online

  12. GPU-based ultra-fast direct aperture optimization for online adaptive radiation therapy

    CERN Document Server

    Men, Chunhua; Jiang, Steve B

    2010-01-01

    Online adaptive radiation therapy (ART) has great promise to significantly reduce normal tissue toxicity and/or improve tumor control through real-time treatment adaptations based on the current patient anatomy. However, the major technical obstacle for clinical realization of online ART, namely the inability to achieve real-time efficiency in treatment re-planning, has yet to be solved. To overcome this challenge, this paper presents our work on the implementation of an intensity modulated radiation therapy (IMRT) direct aperture optimization (DAO) algorithm on graphics processing unit (GPU) based on our previous work on CPU. We formulate the DAO problem as a large-scale convex programming problem, and use an exact method called column generation approach to deal with its extremely large dimensionality on GPU. Five 9-field prostate and five 5-field head-and-neck IMRT clinical cases with 5\\times5 mm2 beamlet size and 2.5\\times2.5\\times2.5 mm3 voxel size were used to evaluate our algorithm on GPU. It takes onl...

  13. GPU-based ultra-fast direct aperture optimization for online adaptive radiation therapy.

    Science.gov (United States)

    Men, Chunhua; Jia, Xun; Jiang, Steve B

    2010-08-07

    Online adaptive radiation therapy (ART) has great promise to significantly reduce normal tissue toxicity and/or improve tumor control through real-time treatment adaptations based on the current patient anatomy. However, the major technical obstacle for clinical realization of online ART, namely the inability to achieve real-time efficiency in treatment re-planning, has yet to be solved. To overcome this challenge, this paper presents our work on the implementation of an intensity-modulated radiation therapy (IMRT) direct aperture optimization (DAO) algorithm on the graphics processing unit (GPU) based on our previous work on the CPU. We formulate the DAO problem as a large-scale convex programming problem, and use an exact method called the column generation approach to deal with its extremely large dimensionality on the GPU. Five 9-field prostate and five 5-field head-and-neck IMRT clinical cases with 5 x 5 mm(2) beamlet size and 2.5 x 2.5 x 2.5 mm(3) voxel size were tested to evaluate our algorithm on the GPU. It takes only 0.7-3.8 s for our implementation to generate high-quality treatment plans on an NVIDIA Tesla C1060 GPU card. Our work has therefore solved a major problem in developing ultra-fast (re-)planning technologies for online ART.

  14. Fast and robust online adaptive planning in stereotactic MR-guided adaptive radiation therapy (SMART) for pancreatic cancer.

    Science.gov (United States)

    Bohoudi, O; Bruynzeel, A M E; Senan, S; Cuijpers, J P; Slotman, B J; Lagerwaard, F J; Palacios, M A

    2017-12-01

    To implement a robust and fast stereotactic MR-guided adaptive radiation therapy (SMART) online strategy in locally advanced pancreatic cancer (LAPC). SMART strategy for plan adaptation was implemented with the MRIdian system (ViewRay Inc.). At each fraction, OAR (re-)contouring is done within a distance of 3cm from the PTV surface. Online plan re-optimization is based on robust prediction of OAR dose and optimization objectives, obtained by building an artificial neural network (ANN). Proposed limited re-contouring strategy for plan adaptation (SMART3CM) is evaluated by comparing 50 previously delivered fractions against a standard (re-)planning method using full-scale OAR (re-)contouring (FULLOAR). Plan quality was assessed using PTV coverage (V95%, Dmean, D1cc) and institutional OAR constraints (e.g. V33Gy). SMART3CM required a significant lower number of optimizations than FULLOAR (4 vs 18 on average) to generate a plan meeting all objectives and institutional OAR constraints. PTV coverage with both strategies was identical (mean V95%=89%). Adaptive plans with SMART3CM exhibited significant lower intermediate and high doses to all OARs than FULLOAR, which also failed in 36% of the cases to adhere to the V33Gy dose constraint. SMART3CM approach for LAPC allows good OAR sparing and adequate target coverage while requiring only limited online (re-)contouring from clinicians. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Radiation Therapy (For Parents)

    Science.gov (United States)

    ... Giving Teens a Voice in Health Care Decisions Radiation Therapy KidsHealth > For Parents > Radiation Therapy Print A ... have many questions and concerns about it. About Radiation Therapy In radiation therapy, high-energy radiation from ...

  16. Benefits of adaptive radiation therapy in lung cancer as a function of replanning frequency

    Energy Technology Data Exchange (ETDEWEB)

    Dial, Christian; Weiss, Elisabeth; Hugo, Geoffrey D., E-mail: gdhugo@vcu.edu [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Siebers, Jeffrey V. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 and Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22908 (United States)

    2016-04-15

    Purpose: To quantify the potential benefit associated with daily replanning in lung cancer in terms of normal tissue dose sparing and to characterize the tradeoff between adaptive benefit and replanning frequency. Methods: A set of synthetic images and contours, derived from weekly active breathing control images of 12 patients who underwent radiation therapy treatment for nonsmall cell lung cancer, is generated for each fraction of treatment using principal component analysis in a way that preserves temporal anatomical trends (e.g., tumor regression). Daily synthetic images and contours are used to simulate four different treatment scenarios: (1) a “no-adapt” scenario that simulates delivery of an initial plan throughout treatment, (2) a “midadapt” scenario that implements a single replan for fraction 18, (3) a “weekly adapt” scenario that simulates weekly adaptations, and (4) a “full-adapt” scenario that simulates daily replanning. An initial intensity modulated radiation therapy plan is created for each patient and replanning is carried out in an automated fashion by reoptimizing beam apertures and weights. Dose is calculated on each image and accumulated to the first in the series using deformable mappings utilized in synthetic image creation for comparison between simulated treatments. Results: Target coverage was maintained and cord tolerance was not exceeded for any of the adaptive simulations. Average reductions in mean lung dose (MLD) and volume of lung receiving 20 Gy or more (V20{sub lung}) were 65 ± 49 cGy (p = 0.000 01) and 1.1% ± 1.2% (p = 0.0006), respectively, for all patients. The largest reduction in MLD for a single patient was 162 cGy, which allowed an isotoxic escalation of the target dose of 1668 cGy. Average reductions in cord max dose, mean esophageal dose (MED), dose received by 66% of the heart (D66{sub heart}), and dose received by 33% of the heart (D33{sub heart}), were 158 ± 280, 117 ± 121, 37 ± 77, and 99 ± 120

  17. Radiation Therapy: Professions in Radiation Therapy

    Science.gov (United States)

    ... Resources Professions Site Index A-Z Professions in Radiation Therapy Radiation Oncologist Therapeutic Medical Physicist Radiation Therapist Dosimetrist Radiation Oncology Nurse Social Worker Dietitian Radiation Oncologist Radiation oncologists are physicians who oversee the ...

  18. 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

  19. Clinical Outcomes With Dose-Escalated Adaptive Radiation Therapy for Urinary Bladder Cancer: A Prospective Study

    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

  20. Implementation of adaptive radiation therapy for urinary bladder carcinoma - Imaging, planning and image guidance

    Energy Technology Data Exchange (ETDEWEB)

    Tuomikoski, Laura; Collan, Juhani; Keyrilaeinen, Jani; Saarilahti, Kauko; Tenhunen, Mikko [Dept. of Oncology, Helsinki Univ. Central Hospital, Helsinki (Finland)], e-mail: laura.tuomikoski@hus.fi; Korhonen, Juha [Dept. of Oncology, Helsinki Univ. Central Hospital, Helsinki (Finland); Clinical Research Inst. Helsinki Univ. Central Hospital Ltd, Helsinki (Finland); Visapaeae, Harri [Dept. of Oncology, Helsinki Univ. Central Hospital, Helsinki (Finland); Dept. of Urology, Helsinki Univ. Central Hospital, Helsinki (Finland); Sairanen, Jukka [Dept. of Urology, Helsinki Univ. Central Hospital, Helsinki (Finland)

    2013-10-15

    Background: Adaptive radiation therapy (ART) for urinary bladder cancer has emerged as a promising alternative to conventional RT with potential to minimize radiation-induced toxicity to healthy tissues. In this work we have studied bladder volume variations and their effect on healthy bladder dose sparing and intra fractional margins, in order to refine our ART strategy. Material and methods: An online ART treatment strategy was followed for five patients with urinary bladder cancer with the tumors demarcated using Lipiodol. A library of 3-4 predefined treatment plans for each patient was created based on four successive computed tomography (CT) scans. Cone beam CT (CBCT) images were acquired before each treatment fraction and after the treatment at least weekly. In partial bladder treatment the sparing of the healthy part of the bladder was investigated. The bladder wall displacements due to bladder filling were determined in three orthogonal directions (CC, AP, DEX-SIN) using the treatment planning CT scans. An ellipsoidal model was applied in order to find the theoretical maximum values for the bladder wall displacements. Moreover, the actual bladder filling rate during treatment was evaluated using the CBCT images. Results: In partial bladder treatment the volume of the bladder receiving high absorbed doses was generally smaller with a full than empty bladder. The estimation of the bladder volume and the upper limit for the intra fractional movement of the bladder wall could be represented with an ellipsoidal model with a reasonable accuracy. Observed maximum growth of bladder dimensions was less than 10 mm in all three orthogonal directions during 15 minute interval. Conclusion: The use of Lipiodol contrast agent enables partial bladder treatment with reduced irradiation of the healthy bladder volume. The ellipsoidal bladder model can be used for the estimation of the bladder volume changes and the upper limit of the bladder wall movement during the treatment

  1. Prostate tumor alignment and continuous, real-time adaptive radiation therapy using electromagnetic fiducials: clinical and cost-utility analyses.

    Science.gov (United States)

    Quigley, Martin M; Mate, Timothy P; Sylvester, John E

    2009-01-01

    and monitoring system to have alignment errors exceeding 5 mm. Almost all patients undergoing external beam radiation of the prostate have been shown to have target organ movement exceeding 3 mm during radiation therapy delivery. The ability of the electromagnetic technology to monitor tumor target location during the same time as radiation therapy is being delivered allows clinicians to provide real time adaptive radiation therapy for prostate cancer. This permits clinicians to intervene when the prostate moves outside the radiation isocenter, which should decrease adverse events and improve patient outcomes. Additionally, a cost-utility analysis has demonstrated that the electromagnetic patient positioning and monitoring system offers patient outcome benefits at a cost that falls well within the payer's customary willingness to pay (WTP) threshold of $50,000 per QALY.

  2. An anthropomorphic abdominal phantom for deformable image registration accuracy validation in adaptive radiation therapy.

    Science.gov (United States)

    Liao, Yuliang; Wang, Linjing; Xu, Xiangdong; Chen, Haibin; Chen, Jiawei; Zhang, Guoqian; Lei, Huaiyu; Wang, Ruihao; Zhang, Shuxu; Gu, Xuejun; Zhen, Xin; Zhou, Linghong

    2017-06-01

    To design and construct a three-dimensional (3D) anthropomorphic abdominal phantom for geometric accuracy and dose summation accuracy evaluations of deformable image registration (DIR) algorithms for adaptive radiation therapy (ART). Organ molds, including liver, kidney, spleen, stomach, vertebra, and two metastasis tumors, were 3D printed using contours from an ovarian cancer patient. The organ molds were molded with deformable gels made of different mixtures of polyvinyl chloride (PVC) and the softener dioctyl terephthalate. Gels with different densities were obtained by a polynomial fitting curve that described the relation between the Hounsfield unit (HU) and PVC-softener blending ratio. The rigid vertebras were constructed by molding of white cement and cellulose pulp. The final abdominal phantom was assembled by arranging all the fabricated organs inside a hollow dummy according to their anatomies, and sealed by deformable gel with averaged HU of muscle and fat. Fiducial landmarks were embedded inside the phantom for spatial accuracy and dose accumulation accuracy studies. Two channels were excavated to facilitate ionization chamber insertion for dosimetric measurements. Phantom properties such as deformable gel elasticity and HU stability were studied. The dosimetric measurement accuracy in the phantom was performed, and the DIR accuracies of three DIR algorithms available in the open source DIR toolkit-DIRART were also validated. The constructed deformable gel showed elastic behavior and was stable in HU values over times, proving to be a practical material for the deformable phantom. The constructed abdominal phantom consisted of realistic anatomies in terms of both anatomical shapes and densities when compared with its reference patient. The dosimetric measurements showed a good agreement with the calculated doses from the treatment planning system. Fiducial-based accuracy analysis conducted on the constructed phantom demonstrated the feasibility of

  3. Adaptive radiation therapy in head and neck cancer for clinical practice: state of the art and practical challenges.

    Science.gov (United States)

    Veresezan, Ovidiu; Troussier, Idriss; Lacout, Alexis; Kreps, Sarah; Maillard, Sophie; Toulemonde, Aude; Marcy, Pierre-Yves; Huguet, Florence; Thariat, Juliette

    2017-02-01

    Modern radiation therapy techniques are characterized by high conformality to tumor volumes and steep dose gradients to spare normal organs. These techniques require accurate clinical target volume definitions and rigorous assessment of set up uncertainties using image guidance, a concept called image-guided radiation therapy. Due to alteration of patient anatomy, changes in tissue density/volumes and tumor shrinkage over the course of treatment, treatment accuracy may be challenged. This may result in excessive irradiation of organs at risk/healthy tissues and undercoverage of target volumes with a significant risk of locoregional failure. Adaptive radiation therapy (ART) is a concept allowing the clinician to reconsider the planned dose based on potential changes to accurately delivering the remaining radiation dose to the tumor while optimally minimizing irradiation of healthy tissues. There is little consensus on how to apply this concept in clinical practice. The current review investigates the current ART issues, including patient selection, clinical/dosimetric criteria and timing for re-planning, and practical technical issues. A practical algorithm is proposed for patient management in cases where ART is required.

  4. Radiation Therapy

    Science.gov (United States)

    ... therapy, including: Fatigue Hair loss Skin changes Swelling/edema Nausea Sexual effects (reduced desire) Blood clots Your ... American Brain Tumor Association 8550 W. Bryn Mawr Ave. Ste 550 Chicago, IL 60631 © 2014 American Brain ...

  5. A 5-Year Investigation of Children's Adaptive Functioning Following Conformal Radiation Therapy for Localized Ependymoma

    Energy Technology Data Exchange (ETDEWEB)

    Netson, Kelli L.; Conklin, Heather M. [Department of Psychology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Wu Shengjie; Xiong Xiaoping [Department of Biostatistics, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States); Merchant, Thomas E., E-mail: thomas.merchant@stjude.org [Division of Radiation Oncology, St. Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2012-09-01

    Purpose: Conformal and intensity modulated radiation therapies have the potential to preserve cognitive outcomes in children with ependymoma; however, functional behavior remains uninvestigated. This longitudinal investigation prospectively examined intelligence quotient (IQ) and adaptive functioning during the first 5 years after irradiation in children diagnosed with ependymoma. Methods and Materials: The study cohort consisted of 123 children with intracranial ependymoma. Mean age at irradiation was 4.60 years (95% confidence interval [CI], 3.85-5.35). Serial neurocognitive evaluations, including an age-appropriate IQ measure and the Vineland Adaptive Behavior Scales (VABS), were completed before irradiation, 6 months after treatment, and annually for 5 years. A total of 579 neurocognitive evaluations were included in these analyses. Results: Baseline IQ and VABS were below normative means (P<.05), although within the average range. Linear mixed models revealed stable IQ and VABS across the follow-up period, except for the VABS Communication Index, which declined significantly (P=.015). Annual change in IQ (-.04 points) did not correlate with annual change in VABS (-.90 to +.44 points). Clinical factors associated with poorer baseline performance (P<.05) included preirradiation chemotherapy, cerebrospinal fluid shunt placement, number and extent of surgical resections, and younger age at treatment. No clinical factors significantly affected the rate of change in scores. Conclusions: Conformal and intensity modulated radiation therapies provided relative sparing of functional outcomes including IQ and adaptive behaviors, even in very young children. Communication skills remained vulnerable and should be the target of preventive and rehabilitative interventions.

  6. Head and Neck Margin Reduction With Adaptive Radiation Therapy: Robustness of Treatment Plans Against Anatomy Changes

    Energy Technology Data Exchange (ETDEWEB)

    Kranen, Simon van; Hamming-Vrieze, Olga; Wolf, Annelisa; Damen, Eugène [Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands); Herk, Marcel van [Christie Hospital and University of Manchester, Manchester (United Kingdom); Sonke, Jan-Jakob, E-mail: j.sonke@nki.nl [Department of Radiation Oncology, Netherlands Cancer Institute, Amsterdam (Netherlands)

    2016-11-01

    Purpose: We set out to investigate loss of target coverage from anatomy changes in head and neck cancer patients as a function of applied safety margins and to verify a cone beam computed tomography (CBCT)–based adaptive strategy with an average patient anatomy to overcome possible target underdosage. Methods and Materials: For 19 oropharyngeal cancer patients, volumetric modulated arc therapy treatment plans (2 arcs; simultaneous integrated boost, 70 and 54.25 Gy; 35 fractions) were automatically optimized with uniform clinical target volume (CTV)–to–planning target volume margins of 5, 3, and 0 mm. We applied b-spline CBCT–to–computed tomography (CT) deformable registration to allow recalculation of the dose on modified CT scans (planning CT deformed to daily CBCT following online positioning) and dose accumulation in the planning CT scan. Patients with deviations in primary or elective CTV coverage >2 Gy were identified as candidates for adaptive replanning. For these patients, a single adaptive intervention was simulated with an average anatomy from the first 10 fractions. Results: Margin reduction from 5 mm to 3 mm to 0 mm generally led to an organ-at-risk (OAR) mean dose (D{sub mean}) sparing of approximately 1 Gy/mm. CTV shrinkage was mainly seen in the elective volumes (up to 10%), likely related to weight loss. Despite online repositioning, substantial systematic errors were present (>3 mm) in lymph node CTV, the parotid glands, and the larynx. Nevertheless, the average increase in OAR dose was small: maximum of 1.2 Gy (parotid glands, D{sub mean}) for all applied margins. Loss of CTV coverage >2 Gy was found in 1, 3, and 7 of 73 CTVs, respectively. Adaptive intervention in 0-mm plans substantially improved coverage: in 5 of 7 CTVs (in 6 patients) to <2 Gy of initially planned. Conclusions: Volumetric modulated arc therapy head and neck cancer treatment plans with 5-mm margins are robust for anatomy changes and show a modest

  7. Radiation Therapy for Cancer

    Science.gov (United States)

    ... is exposed to radiation. Whether IMRT leads to improved control of tumor growth and better survival compared ... treatments. Some patients may receive radiation therapy and chemotherapy at the same time. The timing of radiation ...

  8. Hendee's radiation therapy physics

    CERN Document Server

    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 ...

  9. Online Adaptive Radiation Therapy: Implementation of a New Process of Care.

    Science.gov (United States)

    Lamb, James; Cao, Minsong; Kishan, Amar; Agazaryan, Nzhde; Thomas, David H; Shaverdian, Narek; Yang, Yingli; Ray, Suzette; Low, Daniel A; Raldow, Ann; Steinberg, Michael L; Lee, Percy

    2017-08-27

    Onboard magnetic resonance imaging (MRI) guided radiotherapy is now clinically available in nine centers in the world. This technology has facilitated the clinical implementation of online adaptive radiotherapy (OART), or the ability to alter the daily treatment plan based on tumor and anatomical changes in real-time while the patient is on the treatment table. However, due to the time sensitive nature of OART, implementation in a large and busy clinic has many potential obstacles as well as patient-related safety considerations. In this work, we have described the implementation of this new process of care in the Department of Radiation Oncology at the University of California, Los Angeles (UCLA). We describe the rationale, the initial challenges such as treatment time considerations, technical issues during the process of re-contouring, re-optimization, quality assurance, as well as our current solutions to overcome these challenges. In addition, we describe the implementation of a coverage system with a physician of the day as well as online planners (physicists or dosimetrists) to oversee each OART treatment with patient-specific 'hand-off' directives from the patient's treating physician. The purpose of this effort is to streamline the process without compromising treatment quality and patient safety. As more MRI-guided radiotherapy programs come online, we hope that our experience can facilitate successful adoption of OART in a way that maximally benefits the patient.

  10. TH-A-BRF-02: BEST IN PHYSICS (JOINT IMAGING-THERAPY) - Modeling Tumor Evolution for Adaptive Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y; Lee, CG [University of Toronto, Toronto, ON (Canada); Chan, TCY [University of Toronto, Toronto, ON (Canada); Techna Institute for the Advancement of Technology for Health, Toronto, ON (Canada); Cho, YB; Islam, MK [University of Toronto, Toronto, ON (Canada); Princess Margaret Hospital, Toronto, ON (Canada); Ontario Consortium for Adaptive Interventions in Radiation Oncology (OCAIRO) (Canada)

    2014-06-15

    was supported in part by the Ontario Consortium for Adaptive Interventions in Radiation Oncology (OCAIRO) funded by the Ontario Research Fund (ORF) and the MITACS Accelerate Internship Program.

  11. Radiation therapy -- skin care

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000735.htm Radiation therapy - skin care To use the sharing features ... this page, please enable JavaScript. When you have radiation treatment for cancer, you may have some changes ...

  12. Predictive models for regional hepatic function based on 99mTc-IDA SPECT and local radiation dose for physiologic adaptive radiation therapy.

    Science.gov (United States)

    Wang, Hesheng; Feng, Mary; Frey, Kirk A; Ten Haken, Randall K; Lawrence, Theodore S; Cao, Yue

    2013-08-01

    High-dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed before and during the course of RT using 99mTc-labeled iminodiacetic acid (IDA) single photon emission computed tomography (SPECT) could predict regional liver function reserve after RT. Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans before RT, during, and 1 month after completion of RT. Indocyanine green (ICG) tests, a measure of overall liver function, were performed within 1 day of each scan. Three-dimensional volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After coregistration of the CT/SPECT and the treatment planning CT, HEF dose-response functions during and after RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, dose, priori, and adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function after RT. The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r=-0.80, PIDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of liver damage. Published by Elsevier Inc.

  13. Radiation Therapy - Multiple Languages

    Science.gov (United States)

    ... 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 ...

  14. Beam Orientation Optimization for Intensity Modulated Radiation Therapy using Adaptive l1 Minimization

    CERN Document Server

    Jia, Xun; Lou, Yifei; Jiang, Steve B

    2011-01-01

    Beam orientation optimization (BOO) is a key component in the process of IMRT treatment planning. It determines to what degree one can achieve a good treatment plan quality in the subsequent plan optimization process. In this paper, we have developed a BOO algorithm via adaptive l_1 minimization. Specifically, we introduce a sparsity energy function term into our model which contains weighting factors for each beam angle adaptively adjusted during the optimization process. Such an energy term favors small number of beam angles. By optimizing a total energy function containing a dosimetric term and the sparsity term, we are able to identify the unimportant beam angles and gradually remove them without largely sacrificing the dosimetric objective. In one typical prostate case, the convergence property of our algorithm, as well as the how the beam angles are selected during the optimization process, is demonstrated. Fluence map optimization (FMO) is then performed based on the optimized beam angles. The resulted...

  15. Radiation therapy in horses.

    Science.gov (United States)

    Fidel, Janean L

    2010-04-01

    Although the diagnosis of cancer is relatively uncommon in horses, tumors do occur in this species. Surgery, radiation, and chemotherapy are traditional cancer treatments in all species. In equine patients, surgery has often been the only treatment offered; however, not all tumors can be controlled with surgery alone. In small animal oncology, newer and better therapies are in demand and available. Radiation therapy is often used to control or palliate tumors locally, especially to satisfy clients who demand sophisticated treatments. The large size of equine patients can make radiation therapy difficult, but it is a valuable tool for treating cancer and should not be overlooked when treating horses.

  16. Scale invariant feature transform in adaptive radiation therapy: a tool for deformable image registration assessment and re-planning indication

    Science.gov (United States)

    Paganelli, Chiara; Peroni, Marta; Riboldi, Marco; Sharp, Gregory C.; Ciardo, Delia; Alterio, Daniela; Orecchia, Roberto; Baroni, Guido

    2013-01-01

    Adaptive radiation therapy (ART) aims at compensating for anatomic and pathological changes to improve delivery along a treatment fraction sequence. Current ART protocols require time-consuming manual updating of all volumes of interest on the images acquired during treatment. Deformable image registration (DIR) and contour propagation stand as a state of the ART method to automate the process, but the lack of DIR quality control methods hinder an introduction into clinical practice. We investigated the scale invariant feature transform (SIFT) method as a quantitative automated tool (1) for DIR evaluation and (2) for re-planning decision-making in the framework of ART treatments. As a preliminary test, SIFT invariance properties at shape-preserving and deformable transformations were studied on a computational phantom, granting residual matching errors below the voxel dimension. Then a clinical dataset composed of 19 head and neck ART patients was used to quantify the performance in ART treatments. For the goal (1) results demonstrated SIFT potential as an operator-independent DIR quality assessment metric. We measured DIR group systematic residual errors up to 0.66 mm against 1.35 mm provided by rigid registration. The group systematic errors of both bony and all other structures were also analyzed, attesting the presence of anatomical deformations. The correct automated identification of 18 patients who might benefit from ART out of the total 22 cases using SIFT demonstrated its capabilities toward goal (2) achievement.

  17. Whole breast radiation therapy

    Science.gov (United States)

    ... 11, 2016. www.cancer.gov/types/breast/hp/breast-treatment-pdq . Accessed September 13, 2016. National Cancer Institute. Radiation therapy and you: support for people who have cancer. Cancer.gov Web ...

  18. Principal component analysis-based anatomical motion models for use in adaptive radiation therapy of head and neck cancer patients

    Science.gov (United States)

    Chetvertkov, Mikhail A.

    Purpose: To develop standard and regularized principal component analysis (PCA) models of anatomical changes from daily cone beam CTs (CBCTs) of head and neck (H&N) patients, assess their potential use in adaptive radiation therapy (ART), and to extract quantitative information for treatment response assessment. Methods: Planning CT (pCT) images of H&N patients were artificially deformed to create "digital phantom" images, which modeled systematic anatomical changes during Radiation Therapy (RT). Artificial deformations closely mirrored patients' actual deformations, and were interpolated to generate 35 synthetic CBCTs, representing evolving anatomy over 35 fractions. Deformation vector fields (DVFs) were acquired between pCT and synthetic CBCTs (i.e., digital phantoms), and between pCT and clinical CBCTs. Patient-specific standard PCA (SPCA) and regularized PCA (RPCA) models were built from these synthetic and clinical DVF sets. Eigenvectors, or eigenDVFs (EDVFs), having the largest eigenvalues were hypothesized to capture the major anatomical deformations during treatment. Modeled anatomies were used to assess the dose deviations with respect to the planned dose distribution. Results: PCA models achieve variable results, depending on the size and location of anatomical change. Random changes prevent or degrade SPCA's ability to detect underlying systematic change. RPCA is able to detect smaller systematic changes against the background of random fraction-to-fraction changes, and is therefore more successful than SPCA at capturing systematic changes early in treatment. SPCA models were less successful at modeling systematic changes in clinical patient images, which contain a wider range of random motion than synthetic CBCTs, while the regularized approach was able to extract major modes of motion. For dose assessment it has been shown that the modeled dose distribution was different from the planned dose for the parotid glands due to their shrinkage and shift into

  19. Comparison of adaptive radiotherapy techniques for external radiation therapy of canine bladder cancer.

    Science.gov (United States)

    Nieset, Jessica R; Harmon, Joseph F; Johnson, Thomas E; Larue, Susan M

    2014-01-01

    Daily bladder variations make it difficult to utilize standard radiotherapy as a primary treatment option for muscle-invasive bladder cancer. Our purpose was to develop a model comparing dose distributions of image-guided and adaptive radiotherapy (ART) techniques for canine bladder cancer. Images were obtained retrospectively from cone-beam computed tomography (CBCT) scans used for daily positioning of four dogs undergoing fractionated image-guided radiotherapy (IGRT). Four different treatment plans were modeled for each dog, and dosimetric data were compared. Two plans were developed using planning target volumes based on planning computed tomography (CT) bladder volume. These plans then used bony anatomy or soft tissue anatomy for daily positioning and dosimetric modeling. The third plan type was a hybrid IGRT and ART technique utilizing a library of premade anisotropic planning target volumes using bladder wall motion data and selection of a "plan-of-the-day" determined from positioning CBCT bladder volumes. The fourth plan was an ART technique that constructed a new planning target volume each day based on daily bladder volume as determined by pretreatment CBCT. Dose volume histograms were generated for each plan type and dose distribution for the bladder and rectum were compared between plan types. Irradiated rectal volume decreased and irradiated bladder volume increased as plan conformality increased. ART provided the greatest rectal sparing, with lowest irradiated rectal volume (P radiotherapy techniques for canine bladder cancer showed significant reduction in rectal volume irradiated when compared to nonadaptive techniques, while maintaining appropriate bladder coverage. © 2014 American College of Veterinary Radiology.

  20. Advances in radiation therapy dosimetry

    Directory of Open Access Journals (Sweden)

    Paliwal Bhudatt

    2009-01-01

    Full Text Available During the last decade, there has been an explosion of new radiation therapy planning and delivery tools. We went through a rapid transition from conventional three-dimensional (3D conformal radiation therapy to intensity-modulated radiation therapy (IMRT treatments, and additional new techniques for motion-adaptive radiation therapy are being introduced. These advances push the frontiers in our effort to provide better patient care; and with the addition of IMRT, temporal dimensions are major challenges for the radiotherapy patient dosimetry and delivery verification. Advanced techniques are less tolerant to poor implementation than are standard techniques. Mis-administrations are more difficult to detect and can possibly lead to poor outcomes for some patients. Instead of presenting a manual on quality assurance for radiation therapy, this manuscript provides an overview of dosimetry verification tools and a focused discussion on breath holding, respiratory gating and the applications of four-dimensional computed tomography in motion management. Some of the major challenges in the above areas are discussed.

  1. Clinical Outcomes of Image Guided Adaptive Hypofractionated Weekly Radiation Therapy for Bladder Cancer in Patients Unsuitable for Radical Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hafeez, Shaista, E-mail: shaista.hafeez@icr.ac.uk [The Institute of Cancer Research, London (United Kingdom); The Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); McDonald, Fiona; Lalondrelle, Susan [The Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); McNair, Helen; Warren-Oseni, Karole; Jones, Kelly [The Institute of Cancer Research, London (United Kingdom); The Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); Harris, Victoria [The Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); Taylor, Helen; Khoo, Vincent [The Royal Marsden NHS Foundation Trust, London (United Kingdom); Thomas, Karen [The Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); Hansen, Vibeke; Dearnaley, David; Horwich, Alan; Huddart, Robert [The Institute of Cancer Research, London (United Kingdom); The Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom)

    2017-05-01

    Purpose and Objectives: We report on the clinical outcomes of a phase 2 study assessing image guided hypofractionated weekly radiation therapy in bladder cancer patients unsuitable for radical treatment. Methods and Materials: Fifty-five patients with T2-T4aNx-2M0-1 bladder cancer not suitable for cystectomy or daily radiation therapy treatment were recruited. A “plan of the day” radiation therapy approach was used, treating the whole (empty) bladder to 36 Gy in 6 weekly fractions. Acute toxicity was assessed weekly during radiation therapy, at 6 and 12 weeks using the Common Terminology Criteria for Adverse Events version 3.0. Late toxicity was assessed at 6 months and 12 months using Radiation Therapy Oncology Group grading. Cystoscopy was used to assess local control at 3 months. Cumulative incidence function was used to determine local progression at 1 at 2 years. Death without local progression was treated as a competing risk. Overall survival was estimated using the Kaplan-Meier method. Results: Median age was 86 years (range, 68-97 years). Eighty-seven percent of patients completed their prescribed course of radiation therapy. Genitourinary and gastrointestinal grade 3 acute toxicity was seen in 18% (10/55) and 4% (2/55) of patients, respectively. No grade 4 genitourinary or gastrointestinal toxicity was seen. Grade ≥3 late toxicity (any) at 6 and 12 months was seen in 6.5% (2/31) and 4.3% (1/23) of patients, respectively. Local control after radiation therapy was 92% of assessed patients (60% total population). Cumulative incidence of local progression at 1 year and 2 years for all patients was 7% (95% confidence interval [CI] 2%-17%) and 17% (95% CI 8%-29%), respectively. Overall survival at 1 year was 63% (95% CI 48%-74%). Conclusion: Hypofractionated radiation therapy delivered weekly with a plan of the day approach offers good local control with acceptable toxicity in a patient population not suitable for radical bladder treatment.

  2. Predictive Models for Regional Hepatic Function Based on 99mTc-IDA SPECT and Local Radiation Dose for Physiologic Adaptive Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hesheng, E-mail: hesheng@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Frey, Kirk A. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Ten Haken, Randall K.; Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cao, Yue [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan (United States)

    2013-08-01

    Purpose: High-dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed before and during the course of RT using 99mTc-labeled iminodiacetic acid (IDA) single photon emission computed tomography (SPECT) could predict regional liver function reserve after RT. Methods and Materials: Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans before RT, during, and 1 month after completion of RT. Indocyanine green (ICG) tests, a measure of overall liver function, were performed within 1 day of each scan. Three-dimensional volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After coregistration of the CT/SPECT and the treatment planning CT, HEF dose–response functions during and after RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, dose, priori, and adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function after RT. Results: The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r=−0.80, P<.0001), for all time points. Linear correlations between local doses and regional HEFs 1 month after RT were significant in 12 patients. In the priori model, regional HEF after RT was predicted by the planned dose and regional HEF assessed before RT (R=0.71, P<.0001). In the adaptive model, regional HEF after RT was predicted by regional HEF reassessed during RT and the remaining planned local dose (R=0.83, P<.0001). Conclusions: 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies

  3. Multileaf collimator leaf position verification and analysis for adaptive radiation therapy using a video-optical method

    Science.gov (United States)

    Sethna, Sohrab B.

    External beam radiation therapy is commonly used to eliminate and control cancerous tumors. High-energy beams are shaped to match the patient's specific tumor volume, whereby maximizing radiation dose to malignant cells and limiting dose to normal tissue. A multileaf collimator (MLC) consisting of multiple pairs of tungsten leaves is used to conform the radiation beam to the desired treatment field. Advanced treatment methods utilize dynamic MLC settings to conform to multiple treatment fields and provide intensity modulated radiation therapy (IMRT). Future methods would further increase conformity by actively tracking tumor motion caused by patient cardiac and respiratory motion. Leaf position quality assurance for a dynamic MLC is critical as variation between the planned and actual leaf positions could induce significant errors in radiation dose. The goal of this research project is to prototype a video-optical quality assurance system for MLC leaf positions. The system captures light-field images of MLC leaf sequences during dynamic therapy. Image acquisition and analysis software was developed to determine leaf edge positions. The mean absolute difference between QA prototype predicted and caliper measured leaf positions was found to be 0.6 mm with an uncertainty of +/- 0.3 mm. Maximum errors in predicted positions were below 1.0 mm for static fields. The prototype served as a proof of concept for quality assurance of future tumor tracking methods. Specifically, a lung tumor phantom was created to mimic a lung tumor's motion from respiration. The lung tumor video images were superimposed on MLC field video images for visualization and analysis. The toolbox is capable of displaying leaf position, leaf velocity, tumor position, and determining errors between planned and actual treatment fields for dynamic radiation therapy.

  4. 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...

  5. Radiation therapy physics

    CERN Document Server

    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.

  6. TU-AB-303-08: GPU-Based Software Platform for Efficient Image-Guided Adaptive Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Park, S; Robinson, A; McNutt, T; Wong, J; Lee, J [Johns Hopkins University, Baltimore, MD (United States); Plishker, W; Zaki, G [IGI Technologies Inc., College Park, MD (United States); Shekhar, R [IGI Technologies Inc., College Park, MD (United States); Children’s National Medical Center, Washington, D.C. (United States)

    2015-06-15

    Purpose: In this study, we develop an integrated software platform for adaptive radiation therapy (ART) that combines fast and accurate image registration, segmentation, and dose computation/accumulation methods. Methods: The proposed system consists of three key components; 1) deformable image registration (DIR), 2) automatic segmentation, and 3) dose computation/accumulation. The computationally intensive modules including DIR and dose computation have been implemented on a graphics processing unit (GPU). All required patient-specific data including the planning CT (pCT) with contours, daily cone-beam CTs, and treatment plan are automatically queried and retrieved from their own databases. To improve the accuracy of DIR between pCT and CBCTs, we use the double force demons DIR algorithm in combination with iterative CBCT intensity correction by local intensity histogram matching. Segmentation of daily CBCT is then obtained by propagating contours from the pCT. Daily dose delivered to the patient is computed on the registered pCT by a GPU-accelerated superposition/convolution algorithm. Finally, computed daily doses are accumulated to show the total delivered dose to date. Results: Since the accuracy of DIR critically affects the quality of the other processes, we first evaluated our DIR method on eight head-and-neck cancer cases and compared its performance. Normalized mutual-information (NMI) and normalized cross-correlation (NCC) computed as similarity measures, and our method produced overall NMI of 0.663 and NCC of 0.987, outperforming conventional methods by 3.8% and 1.9%, respectively. Experimental results show that our registration method is more consistent and roust than existing algorithms, and also computationally efficient. Computation time at each fraction took around one minute (30–50 seconds for registration and 15–25 seconds for dose computation). Conclusion: We developed an integrated GPU-accelerated software platform that enables accurate and

  7. Modeling Internal Radiation Therapy

    NARCIS (Netherlands)

    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

  8. Optimal schedules of fractionated radiation therapy by way of the greedy principle: biologically-based adaptive boosting

    Science.gov (United States)

    Hanin, Leonid; Zaider, Marco

    2014-08-01

    We revisit a long-standing problem of optimization of fractionated radiotherapy and solve it in considerable generality under the following three assumptions only: (1) repopulation of clonogenic cancer cells between radiation exposures follows linear birth-and-death Markov process; (2) clonogenic cancer cells do not interact with each other; and (3) the dose response function s(D) is decreasing and logarithmically concave. Optimal schedules of fractionated radiation identified in this work can be described by the following ‘greedy’ principle: give the maximum possible dose as soon as possible. This means that upper bounds on the total dose and the dose per fraction reflecting limitations on the damage to normal tissue, along with a lower bound on the time between successive fractions of radiation, determine the optimal radiation schedules completely. Results of this work lead to a new paradigm of dose delivery which we term optimal biologically-based adaptive boosting (OBBAB). It amounts to (a) subdividing the target into regions that are homogeneous with respect to the maximum total dose and maximum dose per fraction allowed by the anatomy and biological properties of the normal tissue within (or adjacent to) the region in question and (b) treating each region with an individual optimal schedule determined by these constraints. The fact that different regions may be treated to different total dose and dose per fraction mean that the number of fractions may also vary between regions. Numerical evidence suggests that OBBAB produces significantly larger tumor control probability than the corresponding conventional treatments.

  9. Radiation Therapy for Gynecologic Cancers

    Science.gov (United States)

    ... 000 members who specialize in treating cancer with radiation therapies. ASTRO is dedicated to improving patient care through ... rtanswers.org © ASTRO 2016 PRINTED ON RECYCLED PAPER Radiation Therapy for Gynecologic Cancers Gynecologic cancers include malignancies of ...

  10. Radiation Therapy: Additional Treatment Options

    Science.gov (United States)

    ... Cancer Upper GI Cancers Search x FIND A RADIATION ONCOLOGIST CLOSE SNIPEND TREATMENT TYPES SNIPSTART Home / Treatment ... novel targeted therapies can act as radiosensitizers. Systemic Radiation Therapy Certain cancers may be treated with radioactive ...

  11. [Nanoparticles and radiation therapy].

    Science.gov (United States)

    Calugaru, Valentin; Magné, Nicolas; Hérault, Joel; Bonvalot, Sylvie; Le Tourneau, Christophe; Thariat, Juliette

    2015-01-01

    Nanoparticles have emerged in oncology as new therapeutic agents of distinct biochemical and physical properties, and pharmacokinetics. Current rationale and clinical applications in combination with radiation therapy were analyzed. A review of the literature was conducted on nanoparticles as radiosensitizers, with a focus on metallic nanoparticles and radiosensitization mechanisms. Nanoparticles are mainly used as vectors for drugs or to potentiate dose deposit selectively in irradiated tissues. Preclinical data suggest a predominating effect in the kilovoltage range through a photoelectric effect and a potential in the megavoltage range under a combination of physical and biochemical (diameter, concentration, site of infusion etc) conditions. Several clinical trials are ongoing with metallic/crystalline nanoparticles. Nanoparticles have shown a potential for better therapeutic index with radiation therapy, which is being increasingly investigated clinically. Copyright © 2014 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  12. [Cardiac effects of radiation therapy].

    Science.gov (United States)

    Tuohinen, Suvi; Turpeinen, Anu; Skyttä, Tanja; Kellokumpu-Lehtinen, Pirkko-Liisa

    2015-01-01

    Because of increased life-expentancy cancer patients having undergone radiation therapy nowadays live longer, and late-appearing adverse effects are therefore playing a more significant role. Radiation therapy given to the chest is known to approximately double the risk of heart disease, the cumulative total radiation dose being the most important risk-increasing factor. The most significant adverse effects appear only years after the treatment. The mortality from late manifestations reduces the total benefit of radiation therapy. Patients with radiation therapy due to a cancer of the left breast or Hodgkin's lymphoma are particularly susceptible to cardiac effects. A safe radiation dose is not known.

  13. Radiation Therapy for Skin Cancer

    Science.gov (United States)

    ... make sure they are safe to use during radiation therapy. • Eat a balanced diet. If food tastes ... your fluid intake. • Treat the skin exposed to radiation with special care. Stay out of the sun, ...

  14. Smart Radiation Therapy Biomaterials.

    Science.gov (United States)

    Ngwa, Wilfred; Boateng, Francis; Kumar, Rajiv; Irvine, Darrell J; Formenti, Silvia; Ngoma, Twalib; Herskind, Carsten; Veldwijk, Marlon R; Hildenbrand, Georg Lars; Hausmann, Michael; Wenz, Frederik; Hesser, Juergen

    2017-03-01

    Radiation therapy (RT) is a crucial component of cancer care, used in the treatment of over 50% of cancer patients. Patients undergoing image guided RT or brachytherapy routinely have inert RT biomaterials implanted into their tumors. The single function of these RT biomaterials is to ensure geometric accuracy during treatment. Recent studies have proposed that the inert biomaterials could be upgraded to "smart" RT biomaterials, designed to do more than 1 function. Such smart biomaterials include next-generation fiducial markers, brachytherapy spacers, and balloon applicators, designed to respond to stimuli and perform additional desirable functions like controlled delivery of therapy-enhancing payloads directly into the tumor subvolume while minimizing normal tissue toxicities. More broadly, smart RT biomaterials may include functionalized nanoparticles that can be activated to boost RT efficacy. This work reviews the rationale for smart RT biomaterials, the state of the art in this emerging cross-disciplinary research area, challenges and opportunities for further research and development, and a purview of potential clinical applications. Applications covered include using smart RT biomaterials for boosting cancer therapy with minimal side effects, combining RT with immunotherapy or chemotherapy, reducing treatment time or health care costs, and other incipient applications. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. The physics of radiation therapy

    CERN Document Server

    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.

  16. Parotid Glands Dose–Effect Relationships Based on Their Actually Delivered Doses: Implications for Adaptive Replanning in Radiation Therapy of Head-and-Neck Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, Klaudia U. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Fernandes, Laura L. [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Vineberg, Karen A.; McShan, Daniel; Antonuk, Alan E. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cornwall, Craig [Department of Hospital Dentistry, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Mathew J. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Balter, James M. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Eisbruch, Avraham, E-mail: eisbruch@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2013-11-15

    Purpose: Doses actually delivered to the parotid glands during radiation therapy often exceed planned doses. We hypothesized that the delivered doses correlate better with parotid salivary output than the planned doses, used in all previous studies, and that determining these correlations will help make decisions regarding adaptive radiation therapy (ART) aimed at reducing the delivered doses. Methods and Materials: In this prospective study, oropharyngeal cancer patients treated definitively with chemoirradiation underwent daily cone-beam computed tomography (CBCT) with clinical setup alignment based on the C2 posterior edge. Parotid glands in the CBCTs were aligned by deformable registration to calculate cumulative delivered doses. Stimulated salivary flow rates were measured separately from each parotid gland pretherapy and periodically posttherapy. Results: Thirty-six parotid glands of 18 patients were analyzed. Average mean planned doses was 32 Gy, and differences from planned to delivered mean gland doses were −4.9 to +8.4 Gy, median difference +2.2 Gy in glands in which delivered doses increased relative to planned. Both planned and delivered mean doses were significantly correlated with posttreatment salivary outputs at almost all posttherapy time points, without statistically significant differences in the correlations. Large dispersions (on average, SD 3.6 Gy) characterized the dose–effect relationships for both. The differences between the cumulative delivered doses and planned doses were evident at first fraction (r=.92, P<.0001) because of complex setup deviations (eg, rotations and neck articulations), uncorrected by the translational clinical alignments. Conclusions: After daily translational setup corrections, differences between planned and delivered doses in most glands were small relative to the SDs of the dose–saliva data, suggesting that ART is not likely to gain measurable salivary output improvement in most cases. These differences were

  17. SU-C-BRA-01: Interactive Auto-Segmentation for Bowel in Online Adaptive MRI-Guided Radiation Therapy by Using a Multi-Region Labeling Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Y; Chen, I; Kashani, R; Wan, H; Maughan, N; Muccigrosso, D; Parikh, P [Washington University School of Medicine, Saint Louis, MO (United States)

    2016-06-15

    Purpose: In MRI-guided online adaptive radiation therapy, re-contouring of bowel is time-consuming and can impact the overall time of patients on table. The study aims to auto-segment bowel on volumetric MR images by using an interactive multi-region labeling algorithm. Methods: 5 Patients with locally advanced pancreatic cancer underwent fractionated radiotherapy (18–25 fractions each, total 118 fractions) on an MRI-guided radiation therapy system with a 0.35 Tesla magnet and three Co-60 sources. At each fraction, a volumetric MR image of the patient was acquired when the patient was in the treatment position. An interactive two-dimensional multi-region labeling technique based on graph cut solver was applied on several typical MRI images to segment the large bowel and small bowel, followed by a shape based contour interpolation for generating entire bowel contours along all image slices. The resulted contours were compared with the physician’s manual contouring by using metrics of Dice coefficient and Hausdorff distance. Results: Image data sets from the first 5 fractions of each patient were selected (total of 25 image data sets) for the segmentation test. The algorithm segmented the large and small bowel effectively and efficiently. All bowel segments were successfully identified, auto-contoured and matched with manual contours. The time cost by the algorithm for each image slice was within 30 seconds. For large bowel, the calculated Dice coefficients and Hausdorff distances (mean±std) were 0.77±0.07 and 13.13±5.01mm, respectively; for small bowel, the corresponding metrics were 0.73±0.08and 14.15±4.72mm, respectively. Conclusion: The preliminary results demonstrated the potential of the proposed algorithm in auto-segmenting large and small bowel on low field MRI images in MRI-guided adaptive radiation therapy. Further work will be focused on improving its segmentation accuracy and lessening human interaction.

  18. 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.

  19. Correction for 'artificial' electron disequilibrium due to cone-beam CT density errors: implications for on-line adaptive stereotactic body radiation therapy of lung.

    Science.gov (United States)

    Disher, Brandon; Hajdok, George; Wang, An; Craig, Jeff; Gaede, Stewart; Battista, Jerry J

    2013-06-21

    Cone-beam computed tomography (CBCT) has rapidly become a clinically useful imaging modality for image-guided radiation therapy. Unfortunately, CBCT images of the thorax are susceptible to artefacts due to scattered photons, beam hardening, lag in data acquisition, and respiratory motion during a slow scan. These limitations cause dose errors when CBCT image data are used directly in dose computations for on-line, dose adaptive radiation therapy (DART). The purpose of this work is to assess the magnitude of errors in CBCT numbers (HU), and determine the resultant effects on derived tissue density and computed dose accuracy for stereotactic body radiation therapy (SBRT) of lung cancer. Planning CT (PCT) images of three lung patients were acquired using a Philips multi-slice helical CT simulator, while CBCT images were obtained with a Varian On-Board Imaging system. To account for erroneous CBCT data, three practical correction techniques were tested: (1) conversion of CBCT numbers to electron density using phantoms, (2) replacement of individual CBCT pixel values with bulk CT numbers, averaged from PCT images for tissue regions, and (3) limited replacement of CBCT lung pixels values (LCT) likely to produce artificial lateral electron disequilibrium. For each corrected CBCT data set, lung SBRT dose distributions were computed for a 6 MV volume modulated arc therapy (VMAT) technique within the Philips Pinnacle treatment planning system. The reference prescription dose was set such that 95% of the planning target volume (PTV) received at least 54 Gy (i.e. D95). Further, we used the relative depth dose factor as an a priori index to predict the effects of incorrect low tissue density on computed lung dose in regions of severe electron disequilibrium. CT number profiles from co-registered CBCT and PCT patient lung images revealed many reduced lung pixel values in CBCT data, with some pixels corresponding to vacuum (-1000 HU). Similarly, CBCT data in a plastic lung

  20. Radiation Therapy for Lung Cancer

    Science.gov (United States)

    ... 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 ...

  1. Proton radiation therapy in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Grein, E.; Duzenli, C.; Pickles, T.; Ma, R.; Paton, K.; Kwa, W.; Harrison, R.; Blackmore, E. [BC Cancer Agency, Vancouver, British Columbia (Canada); TRIUMF, Vancouver, British Columbia (Canada)

    2002-04-01

    The development, commissioning, and implementation of the first Canadian Proton Radiation Therapy facility at TRIUMF in British Columbia is described. This was a collaborative project by the cyclotron physicists and staff at TRIUMF, the medical physicists and radiation oncologists of the Cancer Agency and the ocular oncology physicians of the Eye Care Center at Vancouver Hospital. (author)

  2. Simulated Online Adaptive Magnetic Resonance–Guided Stereotactic Body Radiation Therapy for the Treatment of Oligometastatic Disease of the Abdomen and Central Thorax: Characterization of Potential Advantages

    Energy Technology Data Exchange (ETDEWEB)

    Henke, Lauren; Kashani, Rojano; Yang, Deshan; Zhao, Tianyu; Green, Olga; Olsen, Lindsey; Rodriguez, Vivian; Wooten, H. Omar; Li, H. Harold; Hu, Yanle; Bradley, Jeffrey; Robinson, Clifford; Parikh, Parag; Michalski, Jeff; Mutic, Sasa [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri (United States); Olsen, Jeffrey R., E-mail: Jeffrey.R.Olsen@ucdenver.edu [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States)

    2016-12-01

    Purpose: To characterize potential advantages of online-adaptive magnetic resonance (MR)-guided stereotactic body radiation therapy (SBRT) to treat oligometastatic disease of the non-liver abdomen and central thorax. Methods and Materials: Ten patients treated with RT for unresectable primary or oligometastatic disease of the non-liver abdomen (n=5) or central thorax (n=5) underwent imaging throughout treatment on a clinical MR image guided RT system. The SBRT plans were created on the basis of tumor/organ at risk (OAR) anatomy at initial computed tomography simulation (P{sub I}), and simulated adaptive plans were created on the basis of observed MR image set tumor/OAR “anatomy of the day” (P{sub A}). Each P{sub A} was planned under workflow constraints to simulate online-adaptive RT. Prescribed dose was 50 Gy/5 fractions, with goal coverage of 95% planning target volume (PTV) by 95% of the prescription, subject to hard OAR constraints. The P{sub I} was applied to each MR dataset and compared with P{sub A} to evaluate changes in dose delivered to tumor/OARs, with dose escalation when possible. Results: Hard OAR constraints were met for all P{sub Is} based on anatomy from initial computed tomography simulation, and all P{sub As} based on anatomy from each daily MR image set. Application of the P{sub I} to anatomy of the day caused OAR constraint violation in 19 of 30 cases. Adaptive planning increased PTV coverage in 21 of 30 cases, including 14 cases in which hard OAR constraints were violated by the nonadaptive plan. For 9 P{sub A} cases, decreased PTV coverage was required to meet hard OAR constraints that would have been violated in a nonadaptive setting. Conclusions: Online-adaptive MRI-guided SBRT may allow PTV dose escalation and/or simultaneous OAR sparing compared with nonadaptive SBRT. A prospective clinical trial is underway at our institution to evaluate clinical outcomes of this technique.

  3. Method for microbeam radiation therapy

    Science.gov (United States)

    Slatkin, Daniel N.; Dilmanian, F. Avraham; Spanne, Per O.

    1994-01-01

    A method of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation, in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue.

  4. 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.

  5. A Novel Method for Predicting Late Genitourinary Toxicity After Prostate Radiation Therapy and the Need for Age-Based Risk-Adapted Dose Constraints

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Awad A. [Temple University School of Medicine, Philadelphia, Pennsylvania (United States); Egleston, Brian [Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Alcantara, Pino [Department of Radiation Oncology, Hospital Universitario Clínico San Carlos, Madrid (Spain); Li, Linna [Department of Radiation Oncology, Bryn Mawr Hospital, Bryn Mawr, Pennsylvania (United States); Pollack, Alan [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States); Horwitz, Eric M. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States); Buyyounouski, Mark K., E-mail: mark.buyyounouski@fccc.edu [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania (United States)

    2013-07-15

    Background: There are no well-established normal tissue sparing dose–volume histogram (DVH) criteria that limit the risk of urinary toxicity from prostate radiation therapy (RT). The aim of this study was to determine which criteria predict late toxicity among various DVH parameters when contouring the entire solid bladder and its contents versus the bladder wall. The area under the histogram curve (AUHC) was also analyzed. Methods and Materials: From 1993 to 2000, 503 men with prostate cancer received 3-dimensional conformal RT (median follow-up time, 71 months). The whole bladder and the bladder wall were contoured in all patients. The primary endpoint was grade ≥2 genitourinary (GU) toxicity occurring ≥3 months after completion of RT. Cox regressions of time to grade ≥2 toxicity were estimated separately for the entire bladder and bladder wall. Concordance probability estimates (CPE) assessed model discriminative ability. Before training the models, an external random test group of 100 men was set aside for testing. Separate analyses were performed based on the mean age (≤ 68 vs >68 years). Results: Age, pretreatment urinary symptoms, mean dose (entire bladder and bladder wall), and AUHC (entire bladder and bladder wall) were significant (P<.05) in multivariable analysis. Overall, bladder wall CPE values were higher than solid bladder values. The AUHC for bladder wall provided the greatest discrimination for late bladder toxicity when compared with alternative DVH points, with CPE values of 0.68 for age ≤68 years and 0.81 for age >68 years. Conclusion: The AUHC method based on bladder wall volumes was superior for predicting late GU toxicity. Age >68 years was associated with late grade ≥2 GU toxicity, which suggests that risk-adapted dose constraints based on age should be explored.

  6. Sensitizing Osteosarcoma to Radiation Therapy

    Science.gov (United States)

    Mamo, Tewodros Kebede

    Several strategies to enhance the effects of radiation therapy are being explored for various cancers, with multiple molecular pathways and physical approaches suggested to play a role. One approach to improve the effectiveness of radiation therapy in tumors is the use of radiosensitizing molecules. Among the key radiosensitizing molecules being explored in various cancers include pharmacologic inhibitors of DNA repair and gold nanoparticles that physically enhance the amount of radiation deposited inside cancer cells. The main goal of this thesis is to explore the role of DNA repair inhibition as a radiosensitizing strategy for osteosarcoma cells. Additionally, the thesis investigates the effects of particle size in the application of gold nanoparticles in osteosarcoma cells to help identify the key parameters relevant to choosing an effective gold nanoparticle-based radiosensitizer.

  7. Radiation therapy - questions to ask your doctor

    Science.gov (United States)

    What to ask your doctor about radiation therapy ... National Cancer Institute. Radiation therapy and you: support for people with cancer. Cancer.gov. Updated May 2007. www.cancer.gov/publications/patient-education/radiationttherapy. ...

  8. Intensity-modulated radiation therapy and xerostomia

    National Research Council Canada - National Science Library

    Chambers, Mark S; Weber, Randal S; Garden, Adam S

    2006-01-01

    Conformal radiation with intensity-modulated radiation therapy, IMRT, is a radiation technique that potentially can minimize the dose to salivary glands and thereby decrease the incidence of xerostomia...

  9. 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)

  10. 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.

  11. Intensity-Modulated Radiation Therapy (IMRT)

    Science.gov (United States)

    ... Resources Professions Site Index A-Z Intensity-Modulated Radiation Therapy (IMRT) Intensity-modulated radiotherapy (IMRT) uses linear accelerators ... and after this procedure? What is Intensity-Modulated Radiation Therapy and how is it used? Intensity-modulated radiation ...

  12. Geometric accuracy in radiation therapy: Dosimetric, imaging and economic considerations

    Science.gov (United States)

    Ploquin, Nicolas P.

    In 2007 in Canada, 159,900 men and women will be diagnosed with cancer. Radiation Therapy (RT) is the treatment of cancer by irradiating malignant tissue with ionizing radiation and it is used on up to 50% of all cancers. The objective of radiation therapy is to deliver a lethal dose of radiation to the tumour while sparing the surrounding healthy tissues and organs at risks (OARs). Thus, the accuracy with which the radiation therapy process must be carried out is critical. The presence of setup errors and uncertainties throughout the RT process impacts the dose received by the tumour and OARs and can compromise the outcome for the patient. This thesis focuses on the study of the limiting geometrical accuracy imposed by factors present in radiation therapy process (such as setup errors and uncertainties or the spatial resolution of the imaging systems that we use) and its consequences for the patient. The consequences are quantified through the use of a physical outcome surrogate, the Equivalent Uniform Dose (EUD), which numerically describes the dose distribution received by the target and normal structures surrounding it. A cost-outcome analysis is presented in which the incremental cost of radiation therapy is directly related to the patients outcome (using the EUD) for using various imaging modalities and correction protocols in Image Guided Adaptive Radiation Therapy (IGART).

  13. Missed Radiation Therapy and Cancer Recurrence

    Science.gov (United States)

    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.

  14. Mapping the literature of radiation therapy

    National Research Council Canada - National Science Library

    Delwiche, Frances A

    2013-01-01

    This study characterizes the literature of the radiation therapy profession, identifies the journals most frequently cited by authors writing in this discipline, and determines the level of coverage...

  15. Motion management in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bert, Christoph [GSI, Helmholtzzentrum fuer Schwerionenforschung, Abteilung Biophysik, Darmstadt (Germany)

    2009-07-01

    Radiotherapy of tumors that move during irradiation requires dedicated means to ensure target coverage despite the motion influence. Motion can occur inter-fractionally (e.g. position of the prostate) or intra-fractionally; the most dominant reason for intra-fractional motion is respiration. The standard procedure to reduce the influence of target motion is the use of margins encompassing the clinical target volume (CTV) to form a planning target volume (PTV) that covers all uncertainties. This approach ensures CTV coverage for most treatment modalities but results in therapeutic dose to normal tissue. With the opportunities given by improved imaging techniques such as time-resolved computed tomography (CT) or (cone-beam) CT in treatment position as well as motion mitigation techniques such as gating or tracking the dosimetric influence of target motion could be reduced. Especially for conformal techniques such as intensity modulated radiotherapy (IMRT) or particle therapy only advanced motion mitigation techniques and/or adaptive therapy concepts lead to preservation of the target conformation established for stationary targets in treatments of moving targets. In the scope of the talk an introduction to motion management is given with an emphasis on application in scanned particle beam therapy.

  16. SU-C-204-05: Magnetic Resonance-Induced Adaptive Response to Orthovoltage Radiation Therapy in FSa and SA-NH Mouse Tumor Cell Lines

    Energy Technology Data Exchange (ETDEWEB)

    Mendel, K; Miller, R; Murley, J; Sadinski, M; Grdina, D [University of Chicago, Chicago, IL (United States)

    2016-06-15

    Purpose: To assess the effect of pre-treatment Magnetic Resonance Imaging (MRI) on cell survival following orthovoltage radiation therapy. Methods: This in vitro study examined the survival of FSa cells (extracted from methylcholanthrene-induced fibrosarcoma in the flank of a C3H female mouse) and SA-NH cells (derived from a spontaneously arising murine sarcoma tumor) having undergone an MRI scan prior to radiation exposure. Cell cultures were kept at 37 C, in a humidified environment with 5% CO2, and were grown to confluence prior to the start of the experiment. Each cell culture underwent two, 25 minute MRIs spaced 24 hours apart using a standard brain imaging protocol. The cultures were exposed to a 2 Gy dose of radiation beginning 15 minutes after the end of each MRI scan. Irradiations were performed by a Philips RT250 X-ray generator at 250 kVp and 15 mA. All MR imaging was performed on a 1.5 T Philips Achieva scanner using a head and neck vasculature coil. Results: Cells given an MRI scan prior to radiation exhibited an increase in mean surviving fraction of 10.8% and 9.6% in FSa and SA-NH cells, respectively. The difference was found to be statistically significant in both cell types by a student two-tailed t test with P = 0.011 and P < 0.001 for FSa and SA-NH, respectively. Conclusion: MRI may cause an increase in radio-resistance in FSa and SA-NH cells. If this biological effect is found to be consistent across other cell types and voltage ranges, these results could help inform treatment planning by improving our understanding of the joint effects of MRI and ionizing radiation. This work was supported in part under NIH grant numbers T32 EB002103, NCI R01-CA 132998, DOE Low Dose Program/Project Grant DE-413 SC0001271. DJ Grdina is a paid consultant to Pinnacle Biologics. DJ Grdina and JS Murley are minority equity partners in Pinnacle Oncology LLC.

  17. Epigenomic Adaptation to Low Dose Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Gould, Michael N. [Univ. of Wisconsin, Madison, WI (United States)

    2015-06-30

    The overall hypothesis of this grant application is that the adaptive responses elicited by low dose ionizing radiation (LDIR) result in part from heritable DNA methylation changes in the epigenome. In the final budget period at the University of Wisconsin-Madison, we will specifically address this hypothesis by determining if the epigenetically labile, differentially methylated regions (DMRs) that regulate parental-specific expression of imprinted genes are deregulated in agouti mice by low dose radiation exposure during gestation. This information is particularly important to ascertain given the 1) increased human exposure to medical sources of radiation; 2) increased number of people predicted to live and work in space; and 3) enhanced citizen concern about radiation exposure from nuclear power plant accidents and terrorist ‘dirty bombs.’

  18. Melioidosis: reactivation during radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Jegasothy, B.V.; Goslen, J.B.; Salvatore, M.A.

    1980-05-01

    Melioidosis is caused by Pseudomonas pseudomallei, a gram-negative, motile bacillus which is a naturally occurring soil saprophyte. The organism is endemic in Southeast Asia, the Philippines, Australia, and parts of Central and South America. Most human disease occurs from infection acquired in these countries. Infection with P pseudomallei may produce no apparent clinical disease. Acute pneumonitis or septicemia may result from inhalation of the organism, and inoculation into sites of trauma may cause localized skin abscesses, or the disease may remain latent and be reactivated months or years later by trauma, burns, or pneumococcal pneumonia, diabetic ketoacidosis, influenza, or bronchogenic carcinoma. The last is probably the commonest form of melioidosis seen in the United States. We present the first case of reactivation of melioidosis after radiation therapy for carcinoma of the lung, again emphasizing the need to consider melioidosis in a septic patient with a history of travel, especially to Southeast Asia.

  19. Adaptive Radiation in Mediterranean Cistus (Cistaceae)

    OpenAIRE

    Guzm?n, Beatriz; Lled?, Mar?a Dolores; Vargas, Pablo

    2009-01-01

    BACKGROUND: Adaptive radiation in Mediterranean plants is poorly understood. The white-flowered Cistus lineage consists of 12 species primarily distributed in Mediterranean habitats and is herein subject to analysis. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a "total evidence" analysis combining nuclear (ncpGS, ITS) and plastid (trnL-trnF, trnK-matK, trnS-trnG, rbcL) DNA sequences and using MP and BI to test the hypothesis of radiation as suggested by previous phylogenetic results. One of ...

  20. 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...

  1. Tissues may adapt to radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-08-01

    French scientists discovered radioactivity and developed vaccination, so it is perhaps appropriate that a prominent French cancer specialist should be promoting the idea of a radiation vaccination effect - or radiation adaptation, as he prefers to call it. Raymond Latarjet, of the Institut Curie in Paris, maintains that recent studies at the gene level are showing evidence that with low doses of radiation, there is time for a cell repair mechanism to take effect, and that this seems to provide some protection against subsequent exposure to high doses. He cited experiments in his laboratory in which exposure to a dose of 4 Gy (400 rad) had, predictably, produced a large number of gene mutations in a specimen, but the number of mutations was less than half that number in a specimen that had been exposed to a dose of 0.02 Gy some six hours before exposure to the 4 Gy.

  2. WE-AB-BRA-09: Sensitivity of Plan Re-Optimization to Errors in Deformable Image Registration in Online Adaptive Image-Guided Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    McClain, B; Olsen, J; Green, O; Yang, D; Santanam, L; Olsen, L; Zhao, T; Rodriguez, V; Wooten, H; Mutic, S; Kashani, R [Washington University School of Medicine, St. Louis, Missouri (United States); Victoria, J; Dempsey, J [ViewRay Incorporated, Oakwood Village, OH (United States)

    2015-06-15

    Purpose: Online adaptive therapy (ART) relies on auto-contouring using deformable image registration (DIR). DIR’s inherent uncertainties require user intervention and manual edits while the patient is on the table. We investigated the dosimetric impact of DIR errors on the quality of re-optimized plans, and used the findings to establish regions for focusing manual edits to where DIR errors can Result in clinically relevant dose differences. Methods: Our clinical implementation of online adaptive MR-IGRT involves using DIR to transfer contours from CT to daily MR, followed by a physicians’ edits. The plan is then re-optimized to meet the organs at risk (OARs) constraints. Re-optimized abdomen and pelvis plans generated based on physician edited OARs were selected as the baseline for evaluation. Plans were then re-optimized on auto-deformed contours with manual edits limited to pre-defined uniform rings (0 to 5cm) around the PTV. A 0cm ring indicates that the auto-deformed OARs were used without editing. The magnitude of the variations caused by the non-deterministic optimizer was quantified by repeat re-optimizations on the same geometry to determine the mean and standard deviation (STD). For each re-optimized plan, various volumetric parameters for the PTV, the OARs were extracted along with DVH and isodose evaluation. A plan was deemed acceptable if the variation from the baseline plan was within one STD. Results: Initial results show that for abdomen and pancreas cases, a minimum of 5cm margin around the PTV is required for contour corrections, while for pelvic and liver cases a 2–3 cm margin is sufficient. Conclusion: Focusing manual contour edits to regions of dosimetric relevance can reduce contouring time in the online ART process while maintaining a clinically comparable plan. Future work will further refine the contouring region by evaluating the path along the beams, dose gradients near the target and OAR dose metrics.

  3. 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.

  4. FDG-PET response-adapted therapy

    DEFF Research Database (Denmark)

    Hutchings, Martin

    2014-01-01

    Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is the most accurate tool for staging, treatment monitoring, and response evaluation in Hodgkin lymphoma (HL). Early determination of treatment sensitivity by FDG-PET is the best tool to guide individualized......, response-adapted treatment. Several ongoing or recently completed trials have investigated the use of FDG-PET/CT for early response-adapted HL therapy. The results are encouraging, but the data are immature, and PET response-adapted HL therapy is discouraged outside the setting of clinical trials. PET...

  5. Low-Dose Pretreatment for Radiation Therapy

    OpenAIRE

    Blankenbecler, Richard

    2010-01-01

    In radiotherapy, a large radiation dose must be applied to both cancer and neighboring healthy cells. Recent experiments have shown that a low dose of ionizing radiation turns on certain protective mechanisms that allow a cell to better survive a subsequent high dose of radiation. This adaptive response can have important and positive consequences for radiotherapy. This paper describes a simple change in treatment procedures to make use of these beneficial effects. A low dose applied only to ...

  6. Adaptive radiation in mediterranean cistus (cistaceae).

    Science.gov (United States)

    Guzmán, Beatriz; Lledó, María Dolores; Vargas, Pablo

    2009-07-23

    Adaptive radiation in Mediterranean plants is poorly understood. The white-flowered Cistus lineage consists of 12 species primarily distributed in Mediterranean habitats and is herein subject to analysis. We conducted a "total evidence" analysis combining nuclear (ncpGS, ITS) and plastid (trnL-trnF, trnK-matK, trnS-trnG, rbcL) DNA sequences and using MP and BI to test the hypothesis of radiation as suggested by previous phylogenetic results. One of the five well-supported lineages of the Cistus-Halimium complex, the white-flowered Cistus lineage, comprises the higher number of species (12) and is monophyletic. Molecular dating estimates a Mid Pleistocene (1.04+/-0.25 Ma) diversification of the white-flowered lineage into two groups (C. clusii and C. salviifolius lineages), which display asymmetric characteristics: number of species (2 vs. 10), leaf morphologies (linear vs. linear to ovate), floral characteristics (small, three-sepalled vs. small to large, three- or five-sepalled flowers) and ecological attributes (low-land vs. low-land to mountain environments). A positive phenotype-environment correlation has been detected by historical reconstructions of morphological traits (leaf shape, leaf labdanum content and leaf pubescence). Ecological evidence indicates that modifications of leaf shape and size, coupled with differences in labdanum secretion and pubescence density, appear to be related to success of new species in different Mediterranean habitats. The observation that radiation in the Cistus salviifolius lineage has been accompanied by the emergence of divergent leaf traits (such as shape, pubescence and labdanum secretion) in different environments suggets that radiation in the group has been adaptive. Here we argued that the diverse ecological conditions of Mediterranean habitats played a key role in directing the evolution of alternative leaf strategies in this plant group. Key innovation of morphological characteristics is supported by our dated

  7. Adaptive radiation in mediterranean cistus (cistaceae.

    Directory of Open Access Journals (Sweden)

    Beatriz Guzmán

    Full Text Available BACKGROUND: Adaptive radiation in Mediterranean plants is poorly understood. The white-flowered Cistus lineage consists of 12 species primarily distributed in Mediterranean habitats and is herein subject to analysis. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a "total evidence" analysis combining nuclear (ncpGS, ITS and plastid (trnL-trnF, trnK-matK, trnS-trnG, rbcL DNA sequences and using MP and BI to test the hypothesis of radiation as suggested by previous phylogenetic results. One of the five well-supported lineages of the Cistus-Halimium complex, the white-flowered Cistus lineage, comprises the higher number of species (12 and is monophyletic. Molecular dating estimates a Mid Pleistocene (1.04+/-0.25 Ma diversification of the white-flowered lineage into two groups (C. clusii and C. salviifolius lineages, which display asymmetric characteristics: number of species (2 vs. 10, leaf morphologies (linear vs. linear to ovate, floral characteristics (small, three-sepalled vs. small to large, three- or five-sepalled flowers and ecological attributes (low-land vs. low-land to mountain environments. A positive phenotype-environment correlation has been detected by historical reconstructions of morphological traits (leaf shape, leaf labdanum content and leaf pubescence. Ecological evidence indicates that modifications of leaf shape and size, coupled with differences in labdanum secretion and pubescence density, appear to be related to success of new species in different Mediterranean habitats. CONCLUSIONS/SIGNIFICANCE: The observation that radiation in the Cistus salviifolius lineage has been accompanied by the emergence of divergent leaf traits (such as shape, pubescence and labdanum secretion in different environments suggets that radiation in the group has been adaptive. Here we argued that the diverse ecological conditions of Mediterranean habitats played a key role in directing the evolution of alternative leaf strategies in this plant group

  8. 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....

  9. Preoperative breast radiation therapy: Indications and perspectives

    DEFF Research Database (Denmark)

    Lightowlers, S V; Boersma, L J; Fourquet, A

    2017-01-01

    Preoperative breast radiation therapy (RT) is not a new concept, but older studies failed to change practice. More recently, there has been interest in revisiting preoperative RT using modern techniques. This current perspective discusses the indications, summarises the published literature...

  10. Partial breast radiation therapy - external beam

    Science.gov (United States)

    ... 11, 2016. www.cancer.gov/types/breast/hp/breast-treatment-pdq . Accessed September 13, 2016. National Cancer Institute. Radiation therapy and you: support for people who have cancer. Cancer.gov Web ...

  11. Radiation therapy services in South Africa

    African Journals Online (AJOL)

    mum electron energy capacity greater than 10 MEV. Nine machines have a maximum photon energy capa- city below 10 MEV (Table I). A cyclotron-based 66. MEV neutron therapy machine used as a national faci- lity is based in the Cape. TABLE I. Megavoltage radiation therapy units in South Africa. Photon. Electron.

  12. Therapy radiation apparatus for veterinary medicine

    Energy Technology Data Exchange (ETDEWEB)

    Parris, D.M.

    1987-03-03

    A radiation device is described for use in veterinary medicine, for treating exterior and interior portions of animal bodies, comprising: (a) power supply means providing selected voltages; (b) high frequency oscillator means; (c) frequency divider means responsive to the oscillator means, and adapted to control switch means for modulating a voltage supply for at least one non-laser broad band infrared radiation diode providing an expanding beam of radiation; and (d) means for applying at least one one-laser broad band infrared radiation diode to a dermal surface of an animal.

  13. Radiation therapy. Recent advances and nursing implications.

    Science.gov (United States)

    Strohl, R A

    1990-06-01

    Radiation therapy is one of the oldest treatments available for cancer management. Since the discovery of x-rays and radioactivity in the 1890s, patients have been treated with radiation. Advances in equipment and in the understanding of radiobiology permit delivery of effective doses of radiation to tumors while minimizing normal tissue damage. Recent advances in radiation have expanded the scope of treatment. Large-field, large-dose radiation, such as half-body treatment, permits treatment of metastatic disease in an effective and well-tolerated manner in patients too ill to travel for therapy. Total skin electron therapy has been successful in managing extensive skin disease. Hyperfractionated treatment is an experimental approach that attempts to achieve better tumor control by treating with two fractions per day. Intraoperative radiation is a conceptually sound but logistically cumbersome plan in which treatment is given in a single fraction at the time of surgery. Its full potential may be realized when the technical difficulties of administration can be overcome. Brachytherapy is the use of radioactive sources implanted directly into the tumor or in a cavity in proximity to the tumor. Techniques have improved in both surgery and radiation, which allow previously inaccessible sites such as the brain to be implanted. Early-stage breast cancer has been effectively managed with lumpectomy followed by radiation. Hyperthermia is the use of heat in conjunction with radiation. Heat has been found to enhance the effect of radiation and limit the repair of radiation damage. The properties of heat cause it to be more damaging to tumor cells than to normal ones. The ability to sensitize cancer cells to radiation and protect normal cells from radiation has been an ongoing research objective. Clinical trials are in progress to isolate effective, easily administered, and nontoxic compounds. The nurse caring for the patient receiving radiation must have an understanding of

  14. Radiation therapy for metastatic spinal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kida, Akio; Fukuda, Haruyuki [Osaka City Univ. (Japan). Medical School; Taniguchi, Shuji; Sakai, Kazuaki

    2000-02-01

    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)

  15. Radiation Therapy and You: Support for People with Cancer

    Science.gov (United States)

    ... Terms Blogs and Newsletters Health Communications Publications Reports Radiation Therapy and You: Support for People With Cancer ... Copy This booklet covers: Questions and Answers About Radiation Therapy. Answers common questions, such as what radiation ...

  16. 42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

    Science.gov (United States)

    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...

  17. [Laser radiations in medical therapy].

    Science.gov (United States)

    Richand, P; Boulnois, J L

    1983-06-30

    The therapeutic effects of various types of laser beams and the various techniques employed are studied. Clinical and experimental research has shown that Helio-Neon laser beams are most effective as biological stimulants and in reducing inflammation. For this reasons they are best used in dermatological surgery cases (varicose ulcers, decubital and surgical wounds, keloid scars, etc.). Infrared diode laser beams have been shown to be highly effective painkillers especially in painful pathologies like postherpetic neuritis. The various applications of laser therapy in acupuncture, the treatment of reflex dermatologia and optic fibre endocavital therapy are presented. The neurophysiological bases of this therapy are also briefly described.

  18. Manifestation pattern of early-late vaginal morbidity after definitive radiation (chemo)therapy and image-guided adaptive brachytherapy for locally advanced cervical cancer: an analysis from the EMBRACE study.

    Science.gov (United States)

    Kirchheiner, Kathrin; Nout, Remi A; Tanderup, Kari; Lindegaard, Jacob C; Westerveld, Henrike; Haie-Meder, Christine; Petrič, Primož; Mahantshetty, Umesh; Dörr, Wolfgang; Pötter, Richard

    2014-05-01

    Brachytherapy in the treatment of locally advanced cervical cancer has changed substantially because of the introduction of combined intracavitary/interstitial applicators and an adaptive target concept, which is the focus of the prospective, multi-institutional EMBRACE study (www.embracestudy.dk) on image-guided adaptive brachytherapy (IGABT). So far, little has been reported about the development of early to late vaginal morbidity in the frame of IGABT. Therefore, the aim of the present EMBRACE analysis was to evaluate the manifestation pattern of vaginal morbidity during the first 2 years of follow-up. In total, 588 patients with a median follow-up time of 15 months and information on vaginal morbidity were included. Morbidity was prospectively assessed at baseline, every 3 months during the first year, and every 6 months in the second year according to the Common Terminology Criteria for Adverse Events, version 3, regarding vaginal stenosis, dryness, mucositis, bleeding, fistula, and other symptoms. Crude incidence rates, actuarial probabilities, and prevalence rates were analyzed. At 2 years, the actuarial probability of severe vaginal morbidity (grade ≥3) was 3.6%. However, mild and moderate vaginal symptoms were still pronounced (grade ≥1, 89%; grade ≥2, 29%), of which the majority developed within 6 months. Stenosis was most frequently observed, followed by vaginal dryness. Vaginal bleeding and mucositis were mainly mild and infrequently reported. Severe vaginal morbidity within the first 2 years after definitive radiation (chemo)therapy including IGABT with intracavitary/interstitial techniques for locally advanced cervical cancer is limited and is significantly less than has been reported from earlier studies. Thus, the new adaptive target concept seems to be a safe treatment with regard to the vagina being an organ at risk. However, mild to moderate vaginal morbidity is still pronounced with currently applied IGABT, and it needs further attention

  19. Cancer and electromagnetic radiation therapy: Quo Vadis?

    CERN Document Server

    Makropoulou, Mersini

    2016-01-01

    In oncology, treating cancer with a beam of photons is a well established therapeutic technique, developed over 100 years, and today over 50% of cancer patients will undergo traditional X-ray radiotherapy. However, ionizing radiation therapy is not the only option, as the high-energy photons delivering their cell-killing radiation energy into cancerous tumor can lead to significant damage to healthy tissues surrounding the tumor, located throughout the beam's path. Therefore, in nowadays, advances in ionizing radiation therapy are competitive to non-ionizing ones, as for example the laser light based therapy, resulting in a synergism that has revolutionized medicine. The use of non-invasive or minimally invasive (e.g. through flexible endoscopes) therapeutic procedures in the management of patients represents a very interesting treatment option. Moreover, as the major breakthrough in cancer management is the individualized patient treatment, new biophotonic techniques, e.g. photo-activated drug carriers, help...

  20. Monte Carlo techniques in radiation therapy

    CERN Document Server

    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...

  1. Advanced Small Animal Conformal Radiation Therapy Device.

    Science.gov (United States)

    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.

  2. Breast Reconstruction and Radiation Therapy: An Update.

    Science.gov (United States)

    Nelson, Jonas A; Disa, Joseph J

    2017-11-01

    With the indications for radiation therapy in the treatment of breast cancer continuing to expand, many patients present for reconstruction having previously had radiation or having a high likelihood of requiring radiation following mastectomy. Both situations are challenging for the plastic surgeon, with different variables impacting the surgical outcome. To date, multiple studies have been performed examining prosthetic and autologous reconstruction in this setting. The purpose of this article was to provide a general platform for understanding the literature as it relates to reconstruction and radiation through an examination of recent systematic reviews and relevant recent publications. We examined this with a focus on the timing of the radiation, and within this context, examined the data from the traditional surgical outcomes standpoint as well as from a patient-reported outcomes perspective. The data provided within will aid in patient counseling and the informed consent process.

  3. 21 CFR 892.5300 - Medical neutron radiation therapy system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical neutron radiation therapy system. 892.5300... therapy system. (a) Identification. A medical neutron radiation therapy system is a device intended to generate high-energy neutrons for radiation therapy. This generic type of device may include signal...

  4. Radiation Therapy for Carcinoma of the Oropharynx

    Energy Technology Data Exchange (ETDEWEB)

    Park, In Kyu; Kim, Jae Choel [Kyungpook National University College of Medicine, Taegu (Korea, Republic of)

    1996-06-15

    Purpose : A retrospective analysis for patients with oropharyngeal carcinoma who were treated with radiation was performed to assess the results of treatment and patterns of failure, and to identify the factors that might influence survival. Methods and Materials : From March 1985 through June 1993, 53 patients with oropharyngeal carcinoma were treated with either radiation therapy alone or combination of neoadjuvant chemotherapy and radiation therapy at the Department of Radiation Oncology, Kyungpook National University Hospital. Patients' ages ranged from 31 to 73 years with a median age of 54 years. There were 47 men and 6 women. Forty-two patients (79.2%) had squamous cell carcinoma, 10 patients (18.9%) had undifferentiated carcinoma and 1 patient (1.9%) had adenoid cystic carcinoma. There were 2 patients with stage I 12 patients with stage II, 12 patients with stage III and 27 patients with stage IV. According to the TNM classification, patients were distributed as follows: T1 7, T2 2, T3 10, T4 7, TX 1, and N0 17, N1 13, N2 21, N3 2. The primary tumor sites were tonsillar region in 36 patients (67.9%) base of the tongue in 12 patients (22.6%), and soft palate in 5 patients (9.4%). Twenty-five patients were treated with radiation therapy alone and twenty-eight patients were treated with one to three courses of chemotherapy followed by radiation therapy. Chemotherapeutic regimens used were either CF (cisplatin and 5-fluorouracil) or CVB (cisplatin, vincristine and bleomycin), Radiation therapy was delivered 180-200 cGy daily,five times a week using 6 MV X-ray with or without 8-10 MeV electron beams. A tumor dose ranged from 4500 cGy to 7740 cGy with a median dose of 7100 cGy. The follow-up time ranged from 4months to 99 months with a median of 21 months. Results : Thrity-seven patients (69.8%) achieved a CR (complete response) and PR (partial response) in 16 patients (30.2%) after radiation therapy. The overall survival rates were 47% at 2 years and 42% at

  5. Image guided adaptive external beam radiation therapy for cervix cancer: Evaluation of a clinically implemented plan-of-the-day technique.

    Science.gov (United States)

    Buschmann, Martin; Majercakova, Katarina; Sturdza, Alina; Smet, Stephanie; Najjari, Dina; Daniel, Michaela; Pötter, Richard; Georg, Dietmar; Seppenwoolde, Yvette

    2017-10-11

    Radiotherapy for cervix cancer is challenging in patients exhibiting large daily changes in the pelvic anatomy, therefore adaptive treatments (ART) have been proposed. The aim of this study was the clinical implementation and subsequent evaluation of plan-of-the-day (POTD)-ART for cervix cancer in supine positioning. The described workflow was based on standard commercial equipment and current quality assurance (QA) methods. A POTD strategy, which employs a VMAT plan library consisting of an empty bladder plan, a full bladder plan and a motion robust backup plan, was developed. Daily adaption was guided by cone beam computed tomography (CBCT) imaging after which the best plan from the library was selected. Sixteen patients were recruited in a clinical study on ART, for nine POTD was applied due to their large organ motion derived from two computed tomography (CT) scans with variable bladder filling. All patients were treated to 45Gy in 25 fractions. Plan selection frequencies over the treatment course were analyzed. Daily doses in the rectum, bladder and cervix-uterus target (CTV-T) were derived and compared to a simulated non-adapted treatment (non-ART), which employed the robust plan for each fraction. Additionally, the adaption consistency was determined by repeating the plan selection procedure one month after treatment by a group of experts. ART-specific QA methods are presented. 225 ART fractions with CBCTs were analyzed. The empty bladder plan was delivered in 49% of the fractions in the first treatment week and this number increased to 78% in the fifth week. The daily coverage of the CTV-T was equivalent between ART and the non-ART simulation, while the daily total irradiated volume V42.75Gy (95% of prescription dose) was reduced by a median of 87cm3. The median delivered V42.75Gy was 1782cm3. Daily delivered doses (V42.75Gy, V40Gy, V30G) to the organs at risk were statistically significantly reduced by ART, with a median difference in daily V42.75Gy in

  6. 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...

  7. Process of Coping with Radiation Therapy.

    Science.gov (United States)

    Johnson, Jean E.; And Others

    1989-01-01

    Evaluated ability of self-regulation and emotional-drive theories to explain effects of informational intervention entailing objective descriptions of experience on outcomes of coping with radiation therapy among 84 men with prostate cancer. Consistent with self-regulation theory, similarity between expectations and experience and degree of…

  8. Stereotactic body radiation therapy delivery validation

    Science.gov (United States)

    Olding, T.; Garcia, L.; Alexander, K.; Schreiner, L. J.; Joshi, C.

    2013-06-01

    This work describes the use of a motion phantom and 1D, 2D, and 3D ion chamber, EBT3 film, electronic portal imaging device (EPID) and FXG gel measurements for dosimetric validation of a stereotactic ablative radiation therapy (SBRT) technique in our clinic. Results show good agreement between the measurements and calculated treatment plan dose.

  9. Stereotactic radiation therapy for large vestibular schwannomas

    NARCIS (Netherlands)

    Mandl, Ellen S.; Meijer, Otto W. M.; Slotman, Ben J.; Vandertop, W. Peter; Peerdeman, Saskia M.

    2010-01-01

    Background and purpose: To evaluate the morbidity and tumor-control rate in the treatment of large vestibular schwannomas (VS) after stereotactic radiation therapy in our institution. Material and methods: Twenty-five consecutive patients (17 men, 8 women) with large VS (diameter 3.0 cm or larger),

  10. Predictive Factor Analysis of Response-Adapted Radiation Therapy for Chemotherapy-Sensitive Pediatric Hodgkin Lymphoma: Analysis of the Children's Oncology Group AHOD 0031 Trial

    Energy Technology Data Exchange (ETDEWEB)

    Charpentier, Anne-Marie [Department of Radiation Oncology, Centre hospitalier de l' Université de Montréal, Montreal, Québec (Canada); Friedman, Debra L. [Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee (United States); Wolden, Suzanne [Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Schwartz, Cindy [Division of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Gill, Bethany; Sykes, Jenna; Albert-Green, Alisha [Biostatistics, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario (Canada); Kelly, Kara M. [Division of Hematology and Oncology, Women & Children' s Hospital of Buffalo, Buffalo, New York (United States); Department of Pediatrics, Roswell Park Cancer Institute, Buffalo, New York (United States); Constine, Louis S. [Radiation Oncology, University of Rochester Medical Center, Rochester, New York (United States); Hodgson, David C., E-mail: David.hodgson@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Cancer Centre, University of Toronto, Toronto, Ontario (Canada)

    2016-12-01

    Purpose: To evaluate whether clinical risk factors could further distinguish children with intermediate-risk Hodgkin lymphoma (HL) with rapid early and complete anatomic response (RER/CR) who benefit significantly from involved-field RT (IFRT) from those who do not, and thereby aid refinement of treatment selection. Methods and Materials: Children with intermediate-risk HL treated on the Children's Oncology Group AHOD 0031 trial who achieved RER/CR with 4 cycles of chemotherapy, and who were randomized to 21-Gy IFRT or no additional therapy (n=716) were the subject of this study. Recursive partitioning analysis was used to identify factors associated with clinically and statistically significant improvement in event-free survival (EFS) after randomization to IFRT. Bootstrap sampling was used to evaluate the robustness of the findings. Result: Although most RER/CR patients did not benefit significantly from IFRT, those with a combination of anemia and bulky limited-stage disease (n=190) had significantly better 4-year EFS with the addition of IFRT (89.3% vs 77.9% without IFRT; P=.019); this benefit was consistently reproduced in bootstrap analyses and after adjusting for other prognostic factors. Conclusion: Although most patients achieving RER/CR had favorable outcomes with 4 cycles of chemotherapy alone, those children with initial bulky stage I/II disease and anemia had significantly better EFS with the addition of IFRT as part of combined-modality therapy. Further work evaluating the interaction of clinical and biologic factors and imaging response is needed to further optimize and refine treatment selection.

  11. Clinical significance of radiation therapy in breast recurrence and prognosis in breast-conserving surgery

    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)

  12. A dosimetric evaluation of volumetric modulated arc therapy, intensity modulated radiation therapy, and three-dimensional conformal radiation therapy for the lower extremity soft tissue sarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sol Min; Song, Seong Chan; Hyun, Sung Eun; Park, Heung Deuk; Lee, Jaegi; Kim, Young Suk; Kim, Gwi Eon [Dept. of Radiation Oncology, Jeju National University Hospital, Jeju (Korea, Republic of)

    2016-06-15

    A dosimetric evaluation of volumetric modulated arc therapy, intensity modulated radiation therapy, and three-dimensional conformal radiation therapy for the lower extremity soft tissue sarcoma For the lower extremity soft tissue sarcoma, volumetric modulated arc therapy, intensity modulated radiation therapy, and three-dimensional conformal radiation therapy were evaluated to compare these three treatment planning technique. The mean doses to the planning target volume and the femur were calculated to evaluate target coverage and the risk of bone fracture during radiation therapy. Volumetric modulated arc therapy can reduce the dose to the femur without compromising target coverage and reduce the treatment time compared with intensity modulated radiation therapy.

  13. Manifestation Pattern of Early-Late Vaginal Morbidity After Definitive Radiation (Chemo)Therapy and Image-Guided Adaptive Brachytherapy for Locally Advanced Cervical Cancer: An Analysis From the EMBRACE Study

    Energy Technology Data Exchange (ETDEWEB)

    Kirchheiner, Kathrin, E-mail: kathrin.kirchheiner@meduniwien.ac.at [Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna/General Hospital of Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna (Austria); Nout, Remi A. [Department of Clinical Oncology, Leiden University Medical Center (Netherlands); Tanderup, Kari; Lindegaard, Jacob C. [Department of Oncology, Aarhus University Hospital (Denmark); Westerveld, Henrike [Department of Radiotherapy, Academic Medical Centre, University of Amsterdam (Netherlands); Haie-Meder, Christine [Department of Radiotherapy, Gustave-Roussy, Villejuif (France); Petrič, Primož [Department of Radiotherapy, Institute of Oncology Ljubljana (Slovenia); Department of Radiotherapy, National Center for Cancer Care and Research, Doha (Qatar); Mahantshetty, Umesh [Department of Radiation Oncology, Tata Memorial Hospital, Mumbai (India); Dörr, Wolfgang; Pötter, Richard [Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna/General Hospital of Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna (Austria)

    2014-05-01

    Background and Purpose: Brachytherapy in the treatment of locally advanced cervical cancer has changed substantially because of the introduction of combined intracavitary/interstitial applicators and an adaptive target concept, which is the focus of the prospective, multi-institutional EMBRACE study ( (www.embracestudy.dk)) on image-guided adaptive brachytherapy (IGABT). So far, little has been reported about the development of early to late vaginal morbidity in the frame of IGABT. Therefore, the aim of the present EMBRACE analysis was to evaluate the manifestation pattern of vaginal morbidity during the first 2 years of follow-up. Methods and Materials: In total, 588 patients with a median follow-up time of 15 months and information on vaginal morbidity were included. Morbidity was prospectively assessed at baseline, every 3 months during the first year, and every 6 months in the second year according to the Common Terminology Criteria for Adverse Events, version 3, regarding vaginal stenosis, dryness, mucositis, bleeding, fistula, and other symptoms. Crude incidence rates, actuarial probabilities, and prevalence rates were analyzed. Results: At 2 years, the actuarial probability of severe vaginal morbidity (grade ≥3) was 3.6%. However, mild and moderate vaginal symptoms were still pronounced (grade ≥1, 89%; grade ≥2, 29%), of which the majority developed within 6 months. Stenosis was most frequently observed, followed by vaginal dryness. Vaginal bleeding and mucositis were mainly mild and infrequently reported. Conclusion: Severe vaginal morbidity within the first 2 years after definitive radiation (chemo)therapy including IGABT with intracavitary/interstitial techniques for locally advanced cervical cancer is limited and is significantly less than has been reported from earlier studies. Thus, the new adaptive target concept seems to be a safe treatment with regard to the vagina being an organ at risk. However, mild to moderate vaginal morbidity

  14. Comparison of particle-radiation-therapy modalities

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, R.G.; Bond, V.P.

    1981-01-01

    The characteristics of dose distribution, beam alignment, and radiobiological advantages accorded to high LET radiation were reviewed and compared for various particle beam radiotherapeutic modalities (neutron, Auger electrons, p, ..pi../sup -/, He, C, Ne, and Ar ions). Merit factors were evaluated on the basis of effective dose to tumor relative to normal tissue, linear energy transfer (LET), and dose localization, at depths of 1, 4, and 10 cm. In general, it was found that neutron capture therapy using an epithermal neutron beam provided the best merit factors available for depths up to 8 cm. The position of fast neutron therapy on the Merit Factor Tables was consistently lower than that of other particle modalities, and above only /sup 60/Co. The largest body of clinical data exists for fast neutron therapy; results are considered by some to be encouraging. It then follows that if benefits with fast neutron therapy are real, additional gains are within reach with other modalities.

  15. 21 CFR 892.5750 - Radionuclide radiation therapy system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide radiation therapy system. 892.5750... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5750 Radionuclide radiation therapy system. (a) Identification. A radionuclide radiation therapy system is a device intended to permit an...

  16. 21 CFR 892.5840 - Radiation therapy simulation system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiation therapy simulation system. 892.5840... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5840 Radiation therapy simulation system. (a) Identification. A radiation therapy simulation system is a fluoroscopic or radiographic x-ray...

  17. Neutrophils, a candidate biomarker and target for radiation therapy?

    Science.gov (United States)

    Schernberg, Antoine; Blanchard, Pierre; Chargari, Cyrus; Deutsch, Eric

    2017-11-01

    Neutrophils are the most abundant blood-circulating white blood cells, continuously generated in the bone marrow. Growing evidence suggests they regulate the innate and adaptive immune system during tumor evolution. This review will first summarize the recent findings on neutrophils as a key player in cancer evolution, then as a potential biomarker, and finally as therapeutic targets, with respective focuses on the interplay with radiation therapy. A complex interplay: Neutrophils have been associated with tumor progression through multiple pathways. Ionizing radiation has cytotoxic effects on cancer cells, but the sensitivity to radiation therapy in vivo differ from isolated cancer cells in vitro, partially due to the tumor microenvironment. Different microenvironmental states, whether baseline or induced, can modulate or even attenuate the effects of radiation, with consequences for therapeutic efficacy. Inflammatory biomarkers: Inflammation-based scores have been widely studied as prognostic biomarkers in cancer patients. We have performed a large retrospective cohort of patients undergoing radiation therapy (1233 patients), with robust relationship between baseline blood neutrophil count and 3-year's patient's overall survival in patients with different cancer histologies. (Pearson's correlation test: p = .001, r = -.93). Therapeutic approaches: Neutrophil-targeting agents are being developed for the treatment of inflammatory and autoimmune diseases. Neutrophils either can exert antitumoral (N1 phenotype) or protumoral (N2 phenotype) activity, depending on the Tumor Micro Environment. Tumor associated N2 neutrophils are characterized by high expression of CXCR4, VEGF, and gelatinase B/MMP9. TGF-β within the tumor microenvironment induces a population of TAN with a protumor N2 phenotype. TGF-β blockade slows tumor growth through activation of CD8 + T cells, macrophages, and tumor associated neutrophils with an antitumor N1 phenotype. This supports

  18. 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

  19. Targeted Radiation Therapy for Cancer Initiative

    Science.gov (United States)

    2017-11-01

    VA 22202- 4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing...Oncology Biology Physics. Contributors to this article are: Avinash R. Chaurasia, Kelly J. Sun, Christopher Premo, Timothy Brand , Brent Tinnel...salvage radiation therapy.” Poster was presented at the ASCO/ASTRO 2013 Genitourinary Cancers Symposium. • Chaurasia A, Sun K, Premo C, Brand T, Tinnel

  20. Biological Bases for Radiation Adaptive Responses in the Lung

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Bobby R. [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Lin, Yong [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Wilder, Julie [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Belinsky, Steven [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States)

    2015-03-01

    Our main research objective was to determine the biological bases for low-dose, radiation-induced adaptive responses in the lung, and use the knowledge gained to produce an improved risk model for radiation-induced lung cancer that accounts for activated natural protection, genetic influences, and the role of epigenetic regulation (epiregulation). Currently, low-dose radiation risk assessment is based on the linear-no-threshold hypothesis, which now is known to be unsupported by a large volume of data.

  1. WE-B-BRD-02: MR Simulation for Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, K. [Deparment of Radiation Oncology, University of California Los Angeles (United States)

    2015-06-15

    The use of MRI in radiation therapy is rapidly increasing. Applications vary from the MRI simulator, to the MRI fused with CT, and to the integrated MRI+RT system. Compared with the standard MRI QA, a broader scope of QA features has to be defined in order to maximize the benefits of using MRI in radiation therapy. These QA features include geometric fidelity, image registration, motion management, cross-system alignment, and hardware interference. Advanced MRI techniques require a specific type of QA, as they are being widely used in radiation therapy planning, dose calculations, post-implant dosimetry, and prognoses. A vigorous and adaptive QA program is crucial to defining the responsibility of the entire radiation therapy group and detecting deviations from the performance of high-quality treatment. As a drastic departure from CT simulation, MRI simulation requires changes in the work flow of treatment planning and image guidance. MRI guided radiotherapy platforms are being developed and commercialized to take the advantage of the advance in knowledge, technology and clinical experience. This symposium will from an educational perspective discuss the scope and specific issues related to MRI guided radiotherapy. Learning Objectives: Understand the difference between a standard and a radiotherapy-specific MRI QA program. Understand the effects of MRI artifacts (geometric distortion and motion) on radiotherapy. Understand advanced MRI techniques (ultrashort echo, fast MRI including dynamic MRI and 4DMRI, diffusion, perfusion, and MRS) and related QA. Understand the methods to prepare MRI for treatment planning (electron density assignment, multimodality image registration, segmentation and motion management). Current status of MRI guided treatment platforms. Dr. Jihong Wang has a research grant with Elekta-MRL project. Dr. Ke Sheng receives research grants from Varian Medical systems.

  2. Adaption By Low Dose Radiation Exposure

    OpenAIRE

    Mitchel, Ron E.J.

    2015-01-01

    The procedures and dose limitations used for radiation protection in the nuclear industry are founded on the assumption that risk is directly proportional to dose, without a threshold. Based on this idea that any dose, no matter how small, will increase risk, radiation protection regulations generally attempt to reduce any exposure to ?as low as reasonably achievable? (ALARA). We know however, that these regulatory assumptions are inconsistent with the known biological effects of low doses. L...

  3. Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seo-Hyun; Nam, Jae-Kyung; Jang, Junho; Lee, Hae-June, E-mail: hjlee@kcch.re.kr; Lee, Yoon-Jin, E-mail: yjlee8@kcch.re.kr

    2015-06-26

    Radiotherapy is a widely used treatment for many tumors. Combination therapy using anti-angiogenic agents and radiation has shown promise; however, these combined therapies are reported to have many limitations in clinical trials. Here, we show that radiation transformed tumor endothelial cells (ECs) to fibroblasts, resulting in reduced vascular endothelial growth factor (VEGF) response and increased Snail1, Twist1, Type I collagen, and transforming growth factor (TGF)-β release. Irradiation of radioresistant Lewis lung carcinoma (LLC) tumors greater than 250 mm{sup 3} increased collagen levels, particularly in large tumor vessels. Furthermore, concomitant sunitinib therapy did not show a significant difference in tumor inhibition versus radiation alone. Thus, we evaluated multimodal therapy that combined pirfenidone, an inhibitor of TGF-induced collagen production, with radiation and sunitinib treatment. This trimodal therapy significantly reduced tumor growth, as compared to radiation alone. Immunohistochemical analysis revealed that radiation-induced collagen deposition and tumor microvessel density were significantly reduced with trimodal therapy, as compared to radiation alone. These data suggest that combined therapy using pirfenidone may modulate the radiation-altered tumor microenvironment, thereby enhancing the efficacy of radiation therapy and concurrent chemotherapy. - Highlights: • Radiation changes tumor endothelial cells to fibroblasts. • Radio-resistant tumors contain collagen deposits, especially in tumor vessels. • Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy. • Pirfenidone reduces radiation-induced collagen deposits in tumors.

  4. 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.

  5. Stereotactic Body Radiation Therapy for Pancreatic Cancer.

    Science.gov (United States)

    Goodman, Karyn A

    2016-01-01

    The role of radiation therapy in the management of pancreatic cancer represents an area of some controversy. However, local disease progression remains a significant cause of morbidity and even mortality for patients with this disease. Stereotactic body radiotherapy (SBRT) is an emerging treatment option for pancreatic cancer, primarily for locally advanced (unresectable) disease as it can provide a therapeutic benefit with significant advantages for patients' quality of life over standard conventional chemoradiation. There may also be a role for SBRT as neoadjuvant therapy for patients with borderline resectable disease to allow conversion to resectability. The objective of this review is to present the data supporting SBRT in pancreatic cancer as well as the potential limitations and caveats of current studies.

  6. Parallelism in adaptive radiations of experimental Escherichia coli populations.

    Science.gov (United States)

    Saxer, Gerda; Travisano, Michael

    2016-01-01

    Adaptive radiations are major contributors to species diversity. Although the underlying mechanisms of adaptive radiations, specialization and trade-offs, are relatively well understood, the tempo and repeatability of adaptive radiations remain elusive. Ecological specialization can occur through the expansion into novel niches or through partitioning of an existing niche. To test how the mode of resource specialization affects the tempo and repeatability of adaptive radiations, we selected replicate bacterial populations in environments that promoted the evolution of diversity either through niche expansion or through niche partitioning, and in a third low-quality single-resource environment, in which diversity was not expected to evolve. Colony size diversity evolved equally fast in environments that provided ecological opportunities regardless of the mode of resource specialization. In the low-quality environments, diversity did not consistently evolve. We observed the largest fitness improvement in the low-quality environment and the smallest the glucose-limited environment. We did not observe a change in the rate of evolutionary change in either trait or environment, suggesting that the pool of beneficial mutations was not exhausted. Overall, the mode of resource specialization did not affect the tempo or repeatability of adaptive radiations. These results demonstrate the limitations of eco-evolutionary feedbacks to affect evolutionary outcomes. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  7. Shape Morphing Adaptive Radiator Technology (SMART) Updates to Techport Entry

    Science.gov (United States)

    Erickson, Lisa; Bertagne, Christopher; Hartl, Darren; Witcomb, John; Cognata, Thomas

    2017-01-01

    The Shape-Morphing Adaptive Radiator Technology (SMART) project builds off the FY16 research effort that developed a flexible composite radiator panel and demonstrated its ability to actuate from SMA's attached to it. The proposed FY17 Shape-Morphing Adaptive Radiator Technology (SMART) project's goal is to 1) develop a practical radiator design with shape memory alloys (SMAs) bonded to the radiator's panel, and 2) build a multi-panel radiator prototype for subsequent system level thermal vacuum tests. The morphing radiator employs SMA materials to passively change its shape to adapt its rate of heat rejection to vehicle requirements. Conceptually, the radiator panel has a naturally closed position (like a cylinder) in a cold environment. Whenever the radiator's temperature gradually rises, SMA's affixed to the face sheet will pull the face sheet open a commensurate amount - increasing the radiators view to space and causing it to reject more heat. In a vehicle, the radiator's variable heat rejection capabilities would reduce the number of additional heat rejection devices in a vehicle's thermal control system. This technology aims to help achieve the required maximum to minimum heat rejection ratio required for manned space vehicles to adopt a lighter, simpler, single loop thermal control architecture (ATCS). Single loop architectures are viewed as an attractive means to reduce mass and complexity over traditional dual-loop solutions. However, fluids generally considered safe enough to flow within crewed cabins (e.g. propylene glycol-water mixtures) have much higher freezing points and viscosities than those used in the external sides of dual loop ATCSs (e.g. Ammonia and HFE7000).

  8. Mutualism with sea anemones triggered the adaptive radiation of clownfishes.

    Science.gov (United States)

    Litsios, Glenn; Sims, Carrie A; Wüest, Rafael O; Pearman, Peter B; Zimmermann, Niklaus E; Salamin, Nicolas

    2012-11-02

    Adaptive radiation is the process by which a single ancestral species diversifies into many descendants adapted to exploit a wide range of habitats. The appearance of ecological opportunities, or the colonisation or adaptation to novel ecological resources, has been documented to promote adaptive radiation in many classic examples. Mutualistic interactions allow species to access resources untapped by competitors, but evidence shows that the effect of mutualism on species diversification can greatly vary among mutualistic systems. Here, we test whether the development of obligate mutualism with sea anemones allowed the clownfishes to radiate adaptively across the Indian and western Pacific oceans reef habitats. We show that clownfishes morphological characters are linked with ecological niches associated with the sea anemones. This pattern is consistent with the ecological speciation hypothesis. Furthermore, the clownfishes show an increase in the rate of species diversification as well as rate of morphological evolution compared to their closest relatives without anemone mutualistic associations. The effect of mutualism on species diversification has only been studied in a limited number of groups. We present a case of adaptive radiation where mutualistic interaction is the likely key innovation, providing new insights into the mechanisms involved in the buildup of biodiversity. Due to a lack of barriers to dispersal, ecological speciation is rare in marine environments. Particular life-history characteristics of clownfishes likely reinforced reproductive isolation between populations, allowing rapid species diversification.

  9. Mutualism with sea anemones triggered the adaptive radiation of clownfishes

    Directory of Open Access Journals (Sweden)

    Litsios Glenn

    2012-11-01

    Full Text Available Abstract Background Adaptive radiation is the process by which a single ancestral species diversifies into many descendants adapted to exploit a wide range of habitats. The appearance of ecological opportunities, or the colonisation or adaptation to novel ecological resources, has been documented to promote adaptive radiation in many classic examples. Mutualistic interactions allow species to access resources untapped by competitors, but evidence shows that the effect of mutualism on species diversification can greatly vary among mutualistic systems. Here, we test whether the development of obligate mutualism with sea anemones allowed the clownfishes to radiate adaptively across the Indian and western Pacific oceans reef habitats. Results We show that clownfishes morphological characters are linked with ecological niches associated with the sea anemones. This pattern is consistent with the ecological speciation hypothesis. Furthermore, the clownfishes show an increase in the rate of species diversification as well as rate of morphological evolution compared to their closest relatives without anemone mutualistic associations. Conclusions The effect of mutualism on species diversification has only been studied in a limited number of groups. We present a case of adaptive radiation where mutualistic interaction is the likely key innovation, providing new insights into the mechanisms involved in the buildup of biodiversity. Due to a lack of barriers to dispersal, ecological speciation is rare in marine environments. Particular life-history characteristics of clownfishes likely reinforced reproductive isolation between populations, allowing rapid species diversification.

  10. Mapping the literature of radiation therapy.

    Science.gov (United States)

    Delwiche, Frances A

    2013-04-01

    This study characterizes the literature of the radiation therapy profession, identifies the journals most frequently cited by authors writing in this discipline, and determines the level of coverage of these journals by major bibliographic indexes. Cited references from three discipline-specific source journals were analyzed according to the Mapping the Literature of Allied Health Project Protocol of the Nursing and Allied Health Resources Section of the Medical Library Association. Bradford's Law of Scattering was applied to all journal references to identify the most frequently cited journal titles. Journal references constituted 77.8% of the total, with books, government documents, Internet sites, and miscellaneous sources making up the remainder. Although a total of 908 journal titles were cited overall, approximately one-third of the journal citations came from just 11 journals. MEDLINE and Scopus provided the most comprehensive indexing of the journal titles in Zones 1 and 2. The source journals were indexed only by CINAHL and Scopus. The knowledgebase of radiation therapy draws heavily from the fields of oncology, radiology, medical physics, and nursing. Discipline-specific publications are not currently well covered by major indexing services, and those wishing to conduct comprehensive literature searches should search multiple resources.

  11. Mapping the literature of radiation therapy

    Science.gov (United States)

    Delwiche, Frances A.

    2013-01-01

    Objective: This study characterizes the literature of the radiation therapy profession, identifies the journals most frequently cited by authors writing in this discipline, and determines the level of coverage of these journals by major bibliographic indexes. Method: Cited references from three discipline-specific source journals were analyzed according to the Mapping the Literature of Allied Health Project Protocol of the Nursing and Allied Health Resources Section of the Medical Library Association. Bradford's Law of Scattering was applied to all journal references to identify the most frequently cited journal titles. Results: Journal references constituted 77.8% of the total, with books, government documents, Internet sites, and miscellaneous sources making up the remainder. Although a total of 908 journal titles were cited overall, approximately one-third of the journal citations came from just 11 journals. MEDLINE and Scopus provided the most comprehensive indexing of the journal titles in Zones 1 and 2. The source journals were indexed only by CINAHL and Scopus. Conclusion: The knowledgebase of radiation therapy draws heavily from the fields of oncology, radiology, medical physics, and nursing. Discipline-specific publications are not currently well covered by major indexing services, and those wishing to conduct comprehensive literature searches should search multiple resources. PMID:23646027

  12. Radiation therapy of the early glottic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Kazushige; Mitsuhashi, Norio; Ikeda, Hajime; Tamaki, Yoshio; Yamakawa, Michitaka; Takahashi, Mitsuhiro; Matsuura, Masana; Niibe, Hideo (Gunma Univ., Maebashi (Japan). School of Medicine)

    1984-10-01

    During the period from 1970 to 1980, 129 patients with laryngeal cancer were treated with radiation therapy alone in the Department of Radiology, Gunma University Hospital. The number of cases with glottic, supraglottic and subglottic cancer were 80 (62%), 38 (29%) and 11 (9%) respectively. The cumulative 5-year survival rate of cases with glottic cancer was 80% (stage I), 70% (stage II), 43% (stage III) and 0% (stage IV). The relative 5-year survival rate was 104%, 87%, 67% and 0%. Twenty-nine patients (36%) were older than 70 years. Of 54 cases with early (T1, T2) glottic cancer, 11 patients developed local relapses. They consist of seven T1a, one T1b and three T2 cases. The lymph nodal relapse was seen in a T1 case. The local relapses were ascribed to the lower tumor dose produced by the technical failures (4 cases) and to the histological factors (4 cases with papilloma like carcinoma). All of the T1 patients with relapses were salvaged with surgery. The larynges of 4 patients salvaged were still in fair preservation. Only one of 3 relapsed T2 cases was salvaged. These treatment results suggest that a regular check-up of general condition of the patients is very important for raising the survival rate, and that the radiation therapy should be first selected for preservation of the larynx in the early glottic cancer.

  13. Study on radiation therapy for prostatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, T. (Yokohama City Univ. (Japan). Faculty of Medicine)

    1981-10-01

    In an attempt to clarify the effects of radiation therapy for prostatic cancer, the author studied 71 prostatic cancer patients with megavoltage radiation therapy at the Cancer Institute Hospital for the past 17 years between 1964 and 1980. Fifty nine out of 71 cases received combined treatment with hormone. Of 71, 28 patients were examined for remaining foci by transperineal needle biopsy at various times after irradiation. The 5-year actuarial survival rate was 100% for stage A, 92% for stage B, 60.2% for stage C and 25.2% for stage D, respectively. Local control rates by digital rectal examination were 92.3% for stage B and 65.5% for stage C, whereas local atrophy rates were 61.5% for stage B and 31% for stage C cases. The positive rate of biopsy was 75%, negative rate was 20.8% and false negative rate was 4.2% within 1 year. The positive rate decreased to 63.6%, while negative rate increased to 31.8% and false positive rate was 4.6% after 1 year. Some cases, in whom the size of the prostate had decreased, showed good prognosis despite the presence of viable cells in biopsy specimens, therefore the waiting policy seemed indicated by frequent local palpation in future follow up to examine any regrowth in size of the lesion.

  14. [Radiation therapy of locally advanced prostate cancer].

    Science.gov (United States)

    Schmidt-Hegemann, N-S; Li, M; Eze, C; Belka, C; Ganswindt, U

    2017-11-01

    The risk classification for localized prostate cancer is based on the groups "low", "intermediate", and "high-risk" prostate cancer. Following this established risk group definition, locally advanced prostate cancer (cT3/4N0M0) has to be classified as "high-risk" prostate cancer. Radical prostatectomy or high-dose radiotherapy, which is combined with androgen deprivation, are the only curative standard treatments for locally advanced prostate cancer. Particularly adequate radiation doses, modern radiotherapy techniques like IMRT/IGRT, as well as long-term androgen suppression are essential for an optimal treatment outcome. In combination with definitive radiotherapy, androgen deprivation therapy should be started neoadjuvant/simultaneous to radiotherapy and is recommended to be continued after radiotherapy. Previous data suggest that 2‑year long-term androgen deprivation in this setting may not be inferior to 3‑year long-term androgen deprivation in high-risk patients. An additional radiation therapy of the lymphatic pathways in men with cN0 locally advanced/high-risk prostate cancer is still a matter of research. Ongoing trials may define selected subgroups with a suggested benefit at its best.

  15. Potential for heavy particle radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Raju, M.R.; Phillips, T.L.

    1977-03-01

    Radiation therapy remains one of the major forms of cancer treatment. When x rays are used in radiotherapy, there are large variations in radiation sensitivity among tumors because of the possible differences in the presence of hypoxic but viable tumor cells, differences in reoxygenation during treatment, differences in distribution of the tumor cells in their cell cycle, and differences in repair of sublethal damage. When high-LET particles are used, depending upon the LET distribution, these differences are reduced considerably. Because of these differences between x rays and high-LET particle effects, the high-LET particles may be more effective on tumor cells for a given effect on normal cells. Heavy particles have potential application in improving radiotherapy because of improved dose localization and possible advantages of high-LET particles due to their radiobiological characteristics. Protons, because of their defined range, Bragg peak, and small effects of scattering, have good dose localization characteristics. The use of protons in radiotherapy minimizes the morbidity of radiotherapy treatment and is very effective in treating deep tumors located near vital structures. Fast neutrons have no physical advantages over /sup 60/Co gamma rays but, because of their high-LET component, could be very effective in treating tumors that are resistant to conventional radiations. Negative pions and heavy ions combine some of the advantages of protons and fast neutrons.

  16. Better Efficacy of Synchrotron Spatially Microfractionated Radiation Therapy Than Uniform Radiation Therapy on Glioma

    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.

  17. Exposure Risks Among Children Undergoing Radiation Therapy: Considerations in the Era of Image Guided Radiation Therapy

    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.”.

  18. Scatter correction for cone-beam CT in radiation therapy.

    Science.gov (United States)

    Zhu, Lei; Xie, Yaoqin; Wang, Jing; Xing, Lei

    2009-06-01

    Cone-beam CT (CBCT) is being increasingly used in modern radiation therapy for patient setup and adaptive replanning. However, due to the large volume of x-ray illumination, scatter becomes a rather serious problem and is considered as one of the fundamental limitations of CBCT image quality. Many scatter correction algorithms have been proposed in literature, while a standard practical solution still remains elusive. In radiation therapy, the same patient is scanned repetitively during a course of treatment, a natural question to ask is whether one can obtain the scatter distribution on the first day of treatment and then use the data for scatter correction in the subsequent scans on different days. To realize this scatter removal scheme, two technical pieces must be in place: (i) A strategy to obtain the scatter distribution in on-board CBCT imaging and (ii) a method to spatially match a prior scatter distribution with the on-treatment CBCT projection data for scatter subtraction. In this work, simple solutions to the two problems are provided. A partially blocked CBCT is used to extract the scatter distribution. The x-ray beam blocker has a strip pattern, such that partial volume can still be accurately reconstructed and the whole-field scatter distribution can be estimated from the detected signals in the shadow regions using interpolation/extrapolation. In the subsequent scans, the patient transformation is determined using a rigid registration of the conventional CBCT and the prior partial CBCT. From the derived patient transformation, the measured scatter is then modified to adapt the new on-treatment patient geometry for scatter correction. The proposed method is evaluated using physical experiments on a clinical CBCT system. On the Catphan 600 phantom, the errors in Hounsfield unit (HU) in the selected regions of interest are reduced from about 350 to below 50 HU; on an anthropomorphic phantom, the error is reduced from 15.7% to 5.4%. The proposed method

  19. Adaptive radiation and ecological diversification of Sulawesi's ancient lake shrimps.

    Science.gov (United States)

    Von Rintelen, Kristina; Glaubrecht, Matthias; Schubart, Christoph D; Wessel, Andreas; Von Rintelen, Thomas

    2010-11-01

    Ancient lakes are natural laboratories for the study of adaptive radiation. Recently, two lake systems on the Indonesian island Sulawesi have emerged as promising new model systems. A species flock of atyid freshwater shrimps in the Malili lake system comprises 15 colorful endemic taxa. Mitochondrial DNA data suggest two independent colonizations by riverine ancestors. Only one colonization event led to subsequent radiation into 14 species, while the second clade comprises just one species. The vast majority of species (n= 12) are habitat specialists, which are confined to the larger Malili clade and include all taxa with species-specific color patterns and a restricted distribution within the five connected Malili lakes. Morphological, genetic, and ecological data are consistent with the existence of an adaptive radiation in the Malili lakes, involving the habitat-specific diversification of trophic morphology. In addition to testing criteria for the recognition of an adaptive radiation, an ancestral state reconstruction reveals an equal probability for either a riverine generalist or a lacustrine specialist as ancestor of the large Malili clade, which is interpreted as indicative of an early stage of habitat specialization within this radiation. Finally, our results suggest that species diversification may have been primarily driven by ecological specialization and allopatric speciation. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

  20. Are Patients Traveling for Intraoperative Radiation Therapy?

    Directory of Open Access Journals (Sweden)

    Kelsey E. Larson

    2017-01-01

    Full Text Available Purpose. One benefit of intraoperative radiation therapy (IORT is that it usually requires a single treatment, thus potentially eliminating distance as a barrier to receipt of whole breast irradiation. The aim of this study was to evaluate the distance traveled by IORT patients at our institution. Methods. Our institutional prospective registry was used to identify IORT patients from 10/2011 to 2/2017. Patient’s home zip code was compared to institution zip code to determine travel distance. Characteristics of local (100 miles patients were compared. Results. 150 were patients included with a median travel distance of 27 miles and mean travel distance of 121 miles. Most were local (68.7%, with the second largest group living faraway (20.0%. Subset analysis of local patients demonstrated 20.4% traveled 1000 miles. The local, regional, and faraway patients did not differ with respect to age, race, tumor characteristics, or whole breast irradiation. Conclusions. Breast cancer patients are traveling for IORT, with 63% traveling >20 miles for care. IORT is an excellent strategy to promote breast conservation in selected patients, particularly those who live remote from a radiation facility.

  1. Ultraviolet radiation therapy and UVR dose models.

    Science.gov (United States)

    Grimes, David Robert

    2015-01-01

    Ultraviolet radiation (UVR) has been an effective treatment for a number of chronic skin disorders, and its ability to alleviate these conditions has been well documented. Although nonionizing, exposure to ultraviolet (UV) radiation is still damaging to deoxyribonucleic acid integrity, and has a number of unpleasant side effects ranging from erythema (sunburn) to carcinogenesis. As the conditions treated with this therapy tend to be chronic, exposures are repeated and can be high, increasing the lifetime probability of an adverse event or mutagenic effect. Despite the potential detrimental effects, quantitative ultraviolet dosimetry for phototherapy is an underdeveloped area and better dosimetry would allow clinicians to maximize biological effect whilst minimizing the repercussions of overexposure. This review gives a history and insight into the current state of UVR phototherapy, including an overview of biological effects of UVR, a discussion of UVR production, illness treated by this modality, cabin design and the clinical implementation of phototherapy, as well as clinical dose estimation techniques. Several dose models for ultraviolet phototherapy are also examined, and the need for an accurate computational dose estimation method in ultraviolet phototherapy is discussed.

  2. Molecular adaptation during adaptive radiation in the Hawaiian endemic genus Schiedea.

    Directory of Open Access Journals (Sweden)

    Maxim V Kapralov

    Full Text Available "Explosive" adaptive radiations on islands remain one of the most puzzling evolutionary phenomena. The rate of phenotypic and ecological adaptations is extremely fast during such events, suggesting that many genes may be under fairly strong selection. However, no evidence for adaptation at the level of protein coding genes was found, so it has been suggested that selection may work mainly on regulatory elements. Here we report the first evidence that positive selection does operate at the level of protein coding genes during rapid adaptive radiations. We studied molecular adaptation in Hawaiian endemic plant genus Schiedea (Caryophyllaceae, which includes closely related species with a striking range of morphological and ecological forms, varying from rainforest vines to woody shrubs growing in desert-like conditions on cliffs. Given the remarkable difference in photosynthetic performance between Schiedea species from different habitats, we focused on the "photosynthetic" Rubisco enzyme, the efficiency of which is known to be a limiting step in plant photosynthesis.We demonstrate that the chloroplast rbcL gene, encoding the large subunit of Rubisco enzyme, evolved under strong positive selection in Schiedea. Adaptive amino acid changes occurred in functionally important regions of Rubisco that interact with Rubisco activase, a chaperone which promotes and maintains the catalytic activity of Rubisco. Interestingly, positive selection acting on the rbcL might have caused favorable cytotypes to spread across several Schiedea species.We report the first evidence for adaptive changes at the DNA and protein sequence level that may have been associated with the evolution of photosynthetic performance and colonization of new habitats during a recent adaptive radiation in an island plant genus. This illustrates how small changes at the molecular level may change ecological species performance and helps us to understand the molecular bases of extremely

  3. Individual skin care during radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, J.S. [Klinik fuer Strahlentherapie (Radioonkologie), Christian-Albrechts-Universitaet Kiel (Germany); Budach, W. [Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Eberhard-Carls-Universitaet Tuebingen (Germany); Doerr, W. [Klinik und Poliklinik fuer Strahlentherapie und Radioonkologie, Medizinische Fakultaet Carl Gustav Carus, Dresden (Germany)

    1998-11-01

    Background: In many clinical settings, the irradiated patient feels additional discomfort by the inhibition of washing the treatment portals and interruption of his adapted skin care habits. Material and methods: An analysis of the scientific recommendations as well as an analysis of the skin dose to the irradiated portals has been performed. An individual scheme for skin care under radiation has been developed. Results: A substantial decrease of the skin dose is achieved in many modern radiation techniques. The consequent reduction of severe skin reactions allowed the use of water and mild soaps as has been approved within many radiotherapy departments. This has lead to an individualized concept for skin care under radiation treatment including the allowance of gentle washing. The skin marks may be saved by using highly tolerable adhesive plasters or small tattoo points, if they are not superfluous by using masks or single referee points instead of marks for the field borders. Conclusions: The individualized concept for skin care during radiation may offer improved life quality to the patient and may decrease the acute reactions of the skin at least in some cases. (orig.) [Deutsch] Hintergrund: In vielen klinischen Situationen erfaehrt der bestrahlte Patient zusaetzliche Belastungen durch das frueher ausgesprochene Waschverbot der Bestrahlungsfelder wie auch durch die Unterbrechung seiner langjaehrigen Hygienegewohnheiten. Material und Methoden: Es wurde eine Analyse der wissenschaftlichen Empfehlungen wie auch der heutzutage bei modernen Bestrahlungstechniken auftretenden Hautdosis durchgefuehrt. Ein individuelles Schema zur Pflege der bestrahlten Haut wurde entwickelt. Ergebnisse: Durch eine Verringerung der Hautdosis und damit der Inzidenz schwerer Hautreaktionen bei modernen Bestrahlungstechniken wird mittlerweile in vielen Abteilungen das `Waschverbot` fuer bestrahlte Haut gelockert. Dies hat zu einem individualisierten Hautpflegekonzept unter der Bestrahlung

  4. Radiation Therapy in Keloids Treatment: History, Strategy, Effectiveness, and Complication

    Directory of Open Access Journals (Sweden)

    Jing Xu

    2017-01-01

    Conclusions: Both past and present evidence support the idea that combination therapy of radiation and surgical therapy is safe and feasible. However, the optimization of treatment strategy was based on different radiation types and should take dose, fractions, interval, and complications into consideration, which will then decrease the rate of recurrence and increase the level of satisfaction.

  5. Efficacy of Six Weeks Infrared Radiation Therapy on Chronic Low ...

    African Journals Online (AJOL)

    TNHJOURNALPH

    The beneficial effect of infrared radiation therapy on chronic low back pain and functional disability as seen in this present study may be related to the hypothesized theory that infrared radiation therapy reduces pain intensity by, vascular changes in blood flow, reflex activity, possibly through the activation of pain gate theory ...

  6. Occurrence of BOOP outside radiation field after radiation therapy for small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hamanishi, Tohru; Oida, Kazukiyo [Tenri Hospital, Nara (Japan); Morimatu, Takafumi (and others)

    2001-09-01

    We report a case of bronchiolitis obliterans organizing pneumonia (BOOP) that occurred outside the radiation field after radiation therapy for small cell lung cancer. A 74-year-old woman received chemotherapy and a total of 60 Gy of radiation therapy to the right hilum and mediastinum for small cell carcinoma of the suprahilar area of the right lung. Radiation pneumonitis developed within the radiation port 3 months after the completion of radiation therapy. She complained of cough and was admitted 7 months after completion of the radiation therapy. Chest radiography and computed tomography demonstrated peripheral alveolar opacities outside the radiation field on the side contralateral to that receiving the radiation therapy. Bronchoalveolar lavage showed that the total cell count was increased, with a markedly increased percentage of lymphocytes. Transbronchial lung biopsy revealed a histologic pattern consistent with BOOP. Treatment with corticosteroids resulted in rapid improvement of the symptoms and complete resolution of the radiographic abnormalities of the left lung. Although some cases of BOOP following radiation therapy for breast cancer have been reported, none of BOOP after radiation therapy for lung cancer have appeared in the literature. (author)

  7. 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.

  8. Quality of Intensity Modulated Radiation Therapy Treatment Plans Using a (60)Co Magnetic Resonance Image Guidance Radiation Therapy System

    DEFF Research Database (Denmark)

    Wooten, H Omar; Green, Olga; Yang, Min

    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...

  9. Cancer and Radiation Therapy: Current Advances and Future Directions

    Science.gov (United States)

    Baskar, Rajamanickam; Lee, Kuo Ann; Yeo, Richard; Yeoh, Kheng-Wei

    2012-01-01

    In recent years remarkable progress has been made towards the understanding of proposed hallmarks of cancer development and treatment. However with its increasing incidence, the clinical management of cancer continues to be a challenge for the 21st century. Treatment modalities comprise of radiation therapy, surgery, chemotherapy, immunotherapy and hormonal therapy. Radiation therapy remains an important component of cancer treatment with approximately 50% of all cancer patients receiving radiation therapy during their course of illness; it contributes towards 40% of curative treatment for cancer. The main goal of radiation therapy is to deprive cancer cells of their multiplication (cell division) potential. Celebrating a century of advances since Marie Curie won her second Nobel Prize for her research into radium, 2011 has been designated the Year of Radiation therapy in the UK. Over the last 100 years, ongoing advances in the techniques of radiation treatment and progress made in understanding the biology of cancer cell responses to radiation will endeavor to increase the survival and reduce treatment side effects for cancer patients. In this review, principles, application and advances in radiation therapy with their biological end points are discussed. PMID:22408567

  10. The tale of the finch: adaptive radiation and behavioural flexibility

    Science.gov (United States)

    Tebbich, Sabine; Sterelny, Kim; Teschke, Irmgard

    2010-01-01

    Darwin's finches are a classic example of adaptive radiation. The ecological diversity of the Galápagos in part explains that radiation, but the fact that other founder species did not radiate suggests that other factors are also important. One hypothesis attempting to identify the extra factor is the flexible stem hypothesis, connecting individual adaptability to species richness. According to this hypothesis, the ancestral finches were flexible and therefore able to adapt to the new and harsh environment they encountered by exploiting new food types and developing new foraging techniques. Phenotypic variation was initially mediated by learning, but genetic accommodation entrenched differences and supplemented them with morphological adaptations. This process subsequently led to diversification and speciation of the Darwin's finches. Their current behaviour is consistent with this hypothesis as these birds use unusual resources by extraordinary means. In this paper, we identify cognitive capacities on which flexibility and innovation depend. The flexible stem hypothesis predicts that we will find high levels of these capacities in all species of Darwin's finches (not just those using innovative techniques). Here, we test that prediction, and find that while most of our data are in line with the flexible stem hypothesis, some are in tension with it. PMID:20194172

  11. On probabilistically defined margins in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Papiez, Lech; Langer, Mark [Department of Radiation Oncology, Indiana University, Indianapolis, IN (United States)

    2006-08-21

    Margins about a target volume subject to external beam radiation therapy are designed to assure that the target volume of tissue to be sterilized by treatment is adequately covered by a lethal dose. Thus, margins are meant to guarantee that all potential variation in tumour position relative to beams allows the tumour to stay within the margin. Variation in tumour position can be broken into two types of dislocations, reducible and irreducible. Reducible variations in tumour position are those that can be accommodated with the use of modern image-guided techniques that derive parameters for compensating motions of patient bodies and/or motions of beams relative to patient bodies. Irreducible variations in tumour position are those random dislocations of a target that are related to errors intrinsic in the design and performance limitations of the software and hardware, as well as limitations of human perception and decision making. Thus, margins in the era of image-guided treatments will need to accommodate only random errors residual in patient setup accuracy (after image-guided setup corrections) and in the accuracy of systems designed to track moving and deforming tissues of the targeted regions of the patient's body. Therefore, construction of these margins will have to be based on purely statistical data. The characteristics of these data have to be determined through the central limit theorem and Gaussian properties of limiting error distributions. In this paper, we show how statistically determined margins are to be designed in the general case of correlated distributions of position errors in three-dimensional space. In particular, we show how the minimal margins for a given level of statistical confidence are found. Then, how they are to be used to determine geometrically minimal PTV that provides coverage of GTV at the assumed level of statistical confidence. Our results generalize earlier recommendations for statistical, central limit theorem

  12. On probabilistically defined margins in radiation therapy

    Science.gov (United States)

    Papiez, Lech; Langer, Mark

    2006-08-01

    Margins about a target volume subject to external beam radiation therapy are designed to assure that the target volume of tissue to be sterilized by treatment is adequately covered by a lethal dose. Thus, margins are meant to guarantee that all potential variation in tumour position relative to beams allows the tumour to stay within the margin. Variation in tumour position can be broken into two types of dislocations, reducible and irreducible. Reducible variations in tumour position are those that can be accommodated with the use of modern image-guided techniques that derive parameters for compensating motions of patient bodies and/or motions of beams relative to patient bodies. Irreducible variations in tumour position are those random dislocations of a target that are related to errors intrinsic in the design and performance limitations of the software and hardware, as well as limitations of human perception and decision making. Thus, margins in the era of image-guided treatments will need to accommodate only random errors residual in patient setup accuracy (after image-guided setup corrections) and in the accuracy of systems designed to track moving and deforming tissues of the targeted regions of the patient's body. Therefore, construction of these margins will have to be based on purely statistical data. The characteristics of these data have to be determined through the central limit theorem and Gaussian properties of limiting error distributions. In this paper, we show how statistically determined margins are to be designed in the general case of correlated distributions of position errors in three-dimensional space. In particular, we show how the minimal margins for a given level of statistical confidence are found. Then, how they are to be used to determine geometrically minimal PTV that provides coverage of GTV at the assumed level of statistical confidence. Our results generalize earlier recommendations for statistical, central limit theorem

  13. Prediction of the thickness of the compensator filter in radiation therapy using computational intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Dehlaghi, Vahab; Taghipour, Mostafa; Haghparast, Abbas [Department of Biomedical Engineering, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Roshani, Gholam Hossein [School of Energy, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of); Rezaei, Abbas [Department of Electrical Engineering, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of); Shayesteh, Sajjad Pashootan [Department of Biomedical Engineering, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Adineh-Vand, Ayoub [Department of Computer Engineering, Islamic Azad University, Kermanshah (Iran, Islamic Republic of); Department of Electrical Engineering, Razi University, Kermanshah (Iran, Islamic Republic of); Karimi, Gholam Reza, E-mail: ghkarimi@razi.ac.ir [Department of Electrical Engineering, Razi University, Kermanshah (Iran, Islamic Republic of)

    2015-04-01

    In this study, artificial neural networks (ANNs) and adaptive neuro-fuzzy inference system (ANFIS) are investigated to predict the thickness of the compensator filter in radiation therapy. In the proposed models, the input parameters are field size (S), off-axis distance, and relative dose (D/D{sub 0}), and the output is the thickness of the compensator. The obtained results show that the proposed ANN and ANFIS models are useful, reliable, and cheap tools to predict the thickness of the compensator filter in intensity-modulated radiation therapy.

  14. State population as a predictor of radiation therapy staffing levels.

    Science.gov (United States)

    Culbertson, John; Carbonneau, Kira; Kudlas, Myke

    2012-05-01

    Considering the cyclical nature of shortages and oversupplies of staffing levels in the labor force, an accurate prediction of future demand for personnel is of great importance. Historically, the profession of radiation therapy has been plagued with these cycles. This study establishes state population as a strong predictor of radiation therapy staffing levels. A linear regression analysis was performed to determine the association between state population and radiation therapy staffing levels from 2002 to 2010. State population is a significant and substantial predictor variable for the number of actively employed and registered radiation therapists, with 89.5% to 91.4% of the variance accounted for from 2002 to 2010. Additional research in estimating future demand in radiation therapy is possible. By monitoring change in state population, health care professionals can proactively address cycles of shortages and oversupplies in staffing levels. Copyright © 2012 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  15. New technologies in radiation therapy: ensuring patient safety, radiation safety and regulatory issues in radiation oncology.

    Science.gov (United States)

    Amols, Howard I

    2008-11-01

    New technologies such as intensity modulated and image guided radiation therapy, computer controlled linear accelerators, record and verify systems, electronic charts, and digital imaging have revolutionized radiation therapy over the past 10-15 y. Quality assurance (QA) as historically practiced and as recommended in reports such as American Association of Physicists in Medicine Task Groups 40 and 53 needs to be updated to address the increasing complexity and computerization of radiotherapy equipment, and the increased quantity of data defining a treatment plan and treatment delivery. While new technology has reduced the probability of many types of medical events, seeing new types of errors caused by improper use of new technology, communication failures between computers, corrupted or erroneous computer data files, and "software bugs" are now being seen. The increased use of computed tomography, magnetic resonance, and positron emission tomography imaging has become routine for many types of radiotherapy treatment planning, and QA for imaging modalities is beyond the expertise of most radiotherapy physicists. Errors in radiotherapy rarely result solely from hardware failures. More commonly they are a combination of computer and human errors. The increased use of radiosurgery, hypofractionation, more complex intensity modulated treatment plans, image guided radiation therapy, and increasing financial pressures to treat more patients in less time will continue to fuel this reliance on high technology and complex computer software. Clinical practitioners and regulatory agencies are beginning to realize that QA for new technologies is a major challenge and poses dangers different in nature than what are historically familiar.

  16. Postoperative radiation therapy for esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Yasumasa; Ono, Koji; Imamura, Masayuki; Hiraoka, Masahiro; Takahashi, Masaji; Abe, Mitsuyuki; Ohishi, Ken; Yanagibashi, Ken; Tobe, Takayoshi (Kyoto Univ. (Japan). Faculty of Medicine)

    1989-04-01

    The value of postoperative radiation therapy (RT) was investigated in 77 patients with esophageal cancer resected between 1977 and 1986. Surgical resection was palliative in 13 of these patients. Although seven of them underwent postoperative irradiation to the residual tumor, all of the patients died within one year. Following potentially curative resection performed in 64 patients, 31 patients received 50 Gy of postoperative RT to the lower neck and the mediastinum (group Ia), seven were unable to receive full-dose postoperative RT (group Ib), and 26 were not treated with postoperative RT (group II). The 5-year survival rate estimated by the Kaplan-Meier method was 54% for group Ia, 29% for group Ib, and 33% for group II, with the difference between groups Ia and II being significant (p<0.025). The local recurrence rate in the mediastinum was lower in group Ia than in group II. Prophylactic postoperative RT for esophageal cancer is a safe and effective regimen for patients with resected disease. (author).

  17. Radiation therapy for the solitary plasmacytoma

    Directory of Open Access Journals (Sweden)

    Esengül Koçak

    2010-06-01

    Full Text Available Plasma-cell neoplasms are classically categorized into four groups as: multiple myeloma (MM, plasma-cell leukemias, solitary plasmacytomas (SP of the bone (SPB, and extramedullary plasmacytomas (EMP. These tumors may be described as localized or diffuse in presentation. Localized plasma-cell neoplasms are rare, and include SP of the skeletal system, accounting for 2-5% of all plasma-cell neoplasms, and EMP of soft tissue, accounting for approximately 3% of all such neoplasms. SP is defined as a solitary mass of neoplastic plasma cells either in the bone marrow or in various soft tissue sites. There appears to be a continuum in which SP often progresses to MM. The main treatment modality for SP is radiation therapy (RT. However, there are no conclusive data in the literature on the optimal RT dose for SP. This review describes the interrelationship of plasma-cell neoplasms, and attempts to determine the minimal RT dose required to obtain local control.

  18. Translation and adaptation procedures for music therapy outcome instruments

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner; McDermott, Orii; Orrell, Martin

    2017-01-01

    With increasing occurrence of international multicentre studies, there is a need for music therapy outcome measures to become more widely available across countries. For countries where English is not the first language, translation and cross-cultural adaptation of outcome measures may be necessary...... procedural steps for the translation and adaptation of music therapy outcome instruments. OBS: 50 free online copies to share: http://www.tandfonline.com/eprint/d8TPZbkVMjzgKg7DjcmT/full...

  19. Clinical applications of advanced rotational radiation therapy

    Science.gov (United States)

    Nalichowski, Adrian

    Purpose: With a fast adoption of emerging technologies, it is critical to fully test and understand its limits and capabilities. In this work we investigate new graphic processing unit (GPU) based treatment planning algorithm and its applications in helical tomotherapy dose delivery. We explore the limits of the system by applying it to challenging clinical cases of total marrow irradiation (TMI) and stereotactic radiosurgery (SRS). We also analyze the feasibility of alternative fractionation schemes for total body irradiation (TBI) and TMI based on reported historical data on lung dose and interstitial pneumonitis (IP) incidence rates. Methods and Materials: An anthropomorphic phantom was used to create TMI plans using the new GPU based treatment planning system and the existing CPU cluster based system. Optimization parameters were selected based on clinically used values for field width, modulation factor and pitch. Treatment plans were also created on Eclipse treatment planning system (Varian Medical Systems Inc, Palo Alto, CA) using volumetric modulated arc therapy (VMAT) for dose delivery on IX treatment unit. A retrospective review was performed of 42 publications that reported IP rates along with lung dose, fractionation regimen, dose rate and chemotherapy. The analysis consisted of nearly thirty two hundred patients and 34 unique radiation regimens. Multivariate logistic regression was performed to determine parameters associated with IP and establish does response function. Results: The results showed very good dosimetric agreement between the GPU and CPU calculated plans. The results from SBRT study show that GPU planning system can maintain 90% target coverage while meeting all the constraints of RTOG 0631 protocol. Beam on time for Tomotherapy and flattening filter free RapidArc was much faster than for Vero or Cyberknife. Retrospective data analysis showed that lung dose and Cyclophosphomide (Cy) are both predictors of IP in TBI/TMI treatments. The

  20. Whole-brain hippocampal sparing radiation therapy: Volume-modulated arc therapy vs intensity-modulated radiation therapy case study

    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.

  1. COMPARISON OF HYPOFRACTIONATED RADIATION THERAPY VERSUS CONVENTIONAL RADIATION THERAPY IN POST MASTECTOMY BREAST CANCER

    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

  2. Adapting Metacognitive Therapy to Children with Generalised Anxiety Disorder

    DEFF Research Database (Denmark)

    Esbjørn, Barbara Hoff; Normann, Nicoline; Reinholdt-Dunne, Marie Louise

    2015-01-01

    -c) with generalised anxiety disorder (GAD) and create suggestions for an adapted manual. The adaptation was based on the structure and techniques used in MCT for adults with GAD. However, the developmental limitations of children were taken into account. For instance, therapy was aided with worksheets, practical...

  3. Intravesical ozone therapy for progressive radiation-induced hematuria.

    Science.gov (United States)

    Clavo, Bernardino; Gutiérrez, Dominga; Martín, Dionisio; Suárez, Gerardo; Hernández, María A; Robaina, Francisco

    2005-06-01

    Progressive radiation-induced cystitis can become a serious clinical problem the therapeutic solution of which is limited and almost invariably aggressive. Ozone therapy is a nonconventional therapy that has been reported to offer benefits in late-onset wound healing and ischemic disorders. This report describes a patient with progressive radiation-induced hematuria from standard conservative treatment that was further treated with ozone therapy. Ozone therapy was achieved by intravesical instillation of ozonized bi-distilled water over a period of 30 minutes, three sessions per week during the first weeks. Later, ozone therapy sessions were decreased and involved ozonized water or direct intravesicular instillation of ozone at 20-25 microg/mL. Hematuria was successfully controlled by intravesical application of ozone therapy. The successes achieved with this technique suggest that intravesicular instillation of ozonized bi-distilled water or ozone merits further investigation with a view to its application to counter this radiation-induced side-effect.

  4. Radiation-induced adaptive response in fish cell lines.

    Science.gov (United States)

    Ryan, Lorna A; Seymour, Colin B; O'Neill-Mehlenbacher, Alicia; Mothersill, Carmel E

    2008-04-01

    There is considerable interest at present in low-dose radiation effects in non-human species. In this study gamma radiation-induced adaptive response, a low-dose radiation effect, was examined in three fish cell lines, (CHSE-214 (Chinook salmon), RTG-2 (rainbow trout) and ZEB-2J (zebrafish)). Cell survival after exposure to direct radiation with or without a 0.1 Gy priming dose, was determined using the colony forming assay for each cell line. Additionally, the occurrence of a bystander effect was examined by measuring the effect of irradiated cell culture medium from the fish cell lines on unexposed reporter cells. A non-linear dose response was observed for all cell lines. ZEB-2J cells were very sensitive to low doses and a hyper-radiosensitive (HRS) response was observed for doses fish cell lines tested. Rather, it was found that pre-exposure of these cells to 0.1 Gy radiation sensitized the cells to subsequent high doses. In CHSE-214 cells, increased sensitivity to subsequent high doses of radiation was observed when the priming and challenge doses were separated by 4 h; however, this sensitizing effect was no longer present when the interval between doses was greater than 8 h. Additionally, a "protective" bystander response was observed in these cell lines; exposure to irradiated medium from fish cells caused increased cloning efficiency in unirradiated reporter cells. The data confirm previous conclusions for mammalian cells that the adaptive response and bystander effect are inversely correlated and contrary to expectations probably have different underlying mechanisms.

  5. [Metacognitive Therapy and Pharmacotherapy - Adapted to Unaccompanied Refugee Minors].

    Science.gov (United States)

    Simons, Michael; Pöter, Britta

    2017-04-01

    Metacognitive Therapy and Pharmacotherapy - Adapted to Unaccompanied Refugee Minors Unaccompanied refugee minors (URM) present a relatively new challenge for adolescent psychotherapy and psychiatry. The evidence of possible treatment approaches is scarce. This paper presents a pragmatic adaptation of Wells' Metacognitive Therapy (MCT) for this population for the first time. Unlike the established trauma-focused treatment approaches MCT does not aim at prolonged exposure to the trauma narrative. Instead, patients shall learn to leave the distressing thoughts alone and to reduce the perseverating thinking processes (rumination and worrying). Adaptations to URM comprise preceding strategies of stabilization and culture specific aspects. In case of severe sleeping problems, medication might be of help.

  6. Waiting times for radiation therapy in Ontario.

    Science.gov (United States)

    Benk, Veronique; Przybysz, Raymond; McGowan, Tom; Paszat, Lawrence

    2006-02-01

    The mass media and clinical journals have reported lengthy waiting times after surgery before initiation of radiation therapy (RT) for cancer across Canada. We aimed to describe the length of time between the last date of surgery or biopsy or chemotherapy and first date of RT. This is a population-based study measuring waiting times for RT in Ontario among all patients with potentially curable cancer of the cervix, tonsil and larynx and a random sample of women who had had breast cancer resection, whose first date of RT fell between Sept. 1, 2001, and Aug. 31, 2002. Abstraction of original health care records provided each patient's demographics, cancer stage and cancer treatment (last surgery, consultation, simulation, first RT). Last dates of chemotherapy before RT were obtained from abstraction or from Ontario Health Insurance Plan (OHIP) files, and last dates of surgery before RT were compared with dates in the Canadian Institute for Health Information (CIHI) Discharge Abstract Database. Waiting times between the last date of surgery or chemotherapy and the first date of RT varied significantly among the health regions of Ontario. Increasing age, but not the presence of comorbidity, was associated with longer waiting times. Women who did not receive postoperative chemotherapy before RT for breast cancer waited significantly longer than all others. Measurement of waiting times for cancer RT must discount time during which adjuvant intravenous chemotherapy is administered after surgery and before RT. There appears to be a formal or informal process by which those at highest risk begin RT most rapidly.

  7. NMR with Combined Antiangiogenic and Radiation Therapies - Breast Cancer

    National Research Council Canada - National Science Library

    Brown, Stephen

    2000-01-01

    The original goal of the present study was to determine optimal strategies for combining radiation and antiangiogenic therapies in spontaneous murine tumors and to evaluate the potential of Nuclear Magnetic Resonance (NMR...

  8. Cardiac complications of radiation therapy. Complications cardiaques de la radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, E.; Baudouy, M.; Morand, P. (Hopital Pasteur, 06 - Nice (France)); Lagrange, J.L. (Centre de Lutte Contre le Cancer Antoine Lacassagne, 06 - Nice (France)); Taillan, B. (Hopital de Cimiez, 06 - Nice (France))

    1993-01-01

    In this article, the authors expose the possible cardiac complications following a radiation therapy: pericarditis, effects on ventricular function, coronary lesions, valvular lesions, electrocardiographic anomalies and pace-maker disfunction.

  9. Current concepts in F18 FDG PET/CT-based Radiation Therapy planning for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Percy eLee

    2012-07-01

    Full Text Available Radiation therapy is an important component of cancer therapy for early stage as well as locally advanced lung cancer. The use of F18 FDG PET/CT has come to the forefront of lung cancer staging and overall treatment decision-making. FDG PET/CT parameters such as standard uptake value and metabolic tumor volume provide important prognostic and predictive information in lung cancer. Importantly, FDG PET/CT for radiation planning has added biological information in defining the gross tumor volume as well as involved nodal disease. For example, accurate target delineation between tumor and atelectasis is facilitated by utilizing PET and CT imaging. Furthermore, there has been meaningful progress in incorporating metabolic information from FDG PET/CT imaging in radiation treatment planning strategies such as radiation dose escalation based on standard uptake value thresholds as well as using respiratory gated PET and CT planning for improved target delineation of moving targets. In addition, PET/CT based follow-up after radiation therapy has provided the possibility of early detection of local as well as distant recurrences after treatment. More research is needed to incorporate other biomarkers such as proliferative and hypoxia biomarkers in PET as well as integrating metabolic information in adaptive, patient-centered, tailored radiation therapy.

  10. The physical basis and future of radiation therapy

    OpenAIRE

    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...

  11. Can radiation therapy treatment planning system accurately predict surface doses in postmastectomy radiation therapy patients?

    Science.gov (United States)

    Wong, Sharon; Back, Michael; Tan, Poh Wee; Lee, Khai Mun; Baggarley, Shaun; Lu, Jaide Jay

    2012-01-01

    Skin doses have been an important factor in the dose prescription for breast radiotherapy. Recent advances in radiotherapy treatment techniques, such as intensity-modulated radiation therapy (IMRT) and new treatment schemes such as hypofractionated breast therapy have made the precise determination of the surface dose necessary. Detailed information of the dose at various depths of the skin is also critical in designing new treatment strategies. The purpose of this work was to assess the accuracy of surface dose calculation by a clinically used treatment planning system and those measured by thermoluminescence dosimeters (TLDs) in a customized chest wall phantom. This study involved the construction of a chest wall phantom for skin dose assessment. Seven TLDs were distributed throughout each right chest wall phantom to give adequate representation of measured radiation doses. Point doses from the CMS Xio® treatment planning system (TPS) were calculated for each relevant TLD positions and results correlated. There were no significant difference between measured absorbed dose by TLD and calculated doses by the TPS (p > 0.05 (1-tailed). Dose accuracy of up to 2.21% was found. The deviations from the calculated absorbed doses were overall larger (3.4%) when wedges and bolus were used. 3D radiotherapy TPS is a useful and accurate tool to assess the accuracy of surface dose. Our studies have shown that radiation treatment accuracy expressed as a comparison between calculated doses (by TPS) and measured doses (by TLD dosimetry) can be accurately predicted for tangential treatment of the chest wall after mastectomy. Copyright © 2012 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  12. Pelvic Normal Tissue Contouring Guidelines for Radiation Therapy: A Radiation Therapy Oncology Group Consensus Panel Atlas

    Energy Technology Data Exchange (ETDEWEB)

    Gay, Hiram A., E-mail: hgay@radonc.wustl.edu [Washington University School of Medicine, St Louis, MO (United States); Barthold, H. Joseph [Commonwealth Hematology and Oncology, Weymouth, MA (United States); Beth Israel Deaconess Medical Center, Boston, MA (Israel); O' Meara, Elizabeth [Radiation Therapy Oncology Group, Philadelphia, PA (United States); Bosch, Walter R. [Washington University School of Medicine, St Louis, MO (United States); El Naqa, Issam [Department of Radiation Oncology, McGill University Health Center, Montreal, Quebec (Canada); Al-Lozi, Rawan [Washington University School of Medicine, St Louis, MO (United States); Rosenthal, Seth A. [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); Lawton, Colleen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Lee, W. Robert [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Sandler, Howard [Cedars-Sinai Medical Center, Los Angeles, CA (United States); Zietman, Anthony [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Myerson, Robert [Washington University School of Medicine, St Louis, MO (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Willett, Christopher [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Kachnic, Lisa A. [Department of Radiation Oncology, Boston Medical Center, Boston University School of Medicine, Boston, MA (United States); Jhingran, Anuja [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Portelance, Lorraine [University of Miami, Miami, FL (United States); Ryu, Janice [Radiation Oncology Centers, Radiological Associates of Sacramento, Sacramento, CA (United States); and others

    2012-07-01

    Purpose: To define a male and female pelvic normal tissue contouring atlas for Radiation Therapy Oncology Group (RTOG) trials. Methods and Materials: One male pelvis computed tomography (CT) data set and one female pelvis CT data set were shared via the Image-Guided Therapy QA Center. A total of 16 radiation oncologists participated. The following organs at risk were contoured in both CT sets: anus, anorectum, rectum (gastrointestinal and genitourinary definitions), bowel NOS (not otherwise specified), small bowel, large bowel, and proximal femurs. The following were contoured in the male set only: bladder, prostate, seminal vesicles, and penile bulb. The following were contoured in the female set only: uterus, cervix, and ovaries. A computer program used the binomial distribution to generate 95% group consensus contours. These contours and definitions were then reviewed by the group and modified. Results: The panel achieved consensus definitions for pelvic normal tissue contouring in RTOG trials with these standardized names: Rectum, AnoRectum, SmallBowel, Colon, BowelBag, Bladder, UteroCervix, Adnexa{sub R}, Adnexa{sub L}, Prostate, SeminalVesc, PenileBulb, Femur{sub R}, and Femur{sub L}. Two additional normal structures whose purpose is to serve as targets in anal and rectal cancer were defined: AnoRectumSig and Mesorectum. Detailed target volume contouring guidelines and images are discussed. Conclusions: Consensus guidelines for pelvic normal tissue contouring were reached and are available as a CT image atlas on the RTOG Web site. This will allow uniformity in defining normal tissues for clinical trials delivering pelvic radiation and will facilitate future normal tissue complication research.

  13. Coronary artery calcium in breast cancer survivors after radiation therapy

    NARCIS (Netherlands)

    Takx, Richard A P; Vliegenthart, Rozemarijn; Schoepf, U Joseph; Pilz, Lothar R; Schoenberg, Stefan O; Morris, Pamela B; Henzler, Thomas; Apfaltrer, Paul

    The purpose of the current study is to investigate whether breast cancer survivors after radiation therapy have a higher burden of coronary artery calcium as a potential surrogate of radiation-induced accelerated coronary artery disease. 333 patients were included. 54 patients underwent chest CT ae

  14. Cranial Radiation Therapy and Damage to Hippocampal Neurogenesis

    Science.gov (United States)

    Monje, Michelle

    2008-01-01

    Cranial radiation therapy is associated with a progressive decline in cognitive function, prominently memory function. Impairment of hippocampal neurogenesis is thought to be an important mechanism underlying this cognitive decline. Recent work has elucidated the mechanisms of radiation-induced failure of neurogenesis. Potential therapeutic…

  15. Prototype demonstration of radiation therapy planning code system

    Energy Technology Data Exchange (ETDEWEB)

    Little, R.C.; Adams, K.J.; Estes, G.P.; Hughes, L.S. III; Waters, L.S. [and others

    1996-09-01

    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.

  16. Organ doses from radiation therapy in atomic bomb survivors.

    Science.gov (United States)

    Kato, K; Antoku, S; Kodama, K; Kawamura, S; Fujita, Y; Komatsu, K; Awa, A A

    2001-06-01

    Previous surveys of radiation therapy among the Life Span Study (LSS) population at the Radiation Effects Research Foundation (RERF) revealed that 1,670 (1.4%) of the LSS participants received radiation treatments before 1984. The data on therapeutic radiation doses are indispensable for studying the relationship between radiation treatments and subsequent cancer occurrences. In this study, the radiation treatments were reproduced experimentally to determine the scattered radiation doses. The experiments were conducted using a female human phantom and various radiation sources, including a medium-voltage X-ray machine and a (60)Co gamma-ray source. Doses were measured using thermoluminescence dosimetry and ionization chambers. Radiation doses were determined for the salivary glands, thyroid gland, breast, lung, stomach, colon, ovary and active bone marrow. The results have been used for documenting the organ doses received by patients in previous surveys. The contribution of therapeutic irradiation to the occurrence of chromosome aberrations was studied using data on doses to active bone marrow from both radiation treatments and atomic bomb exposures in 26 RERF Adult Health Study participants. The results suggest that radiation treatments contributed to a large part of their frequencies of stable-type chromosome aberrations. The therapeutic radiation doses determined in the present study are available for investigating the effects of therapeutic irradiation on the subsequent primary cancers among atomic bomb survivors who received radiation treatments.

  17. Once-Daily Radiation Therapy for Inflammatory Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Lindsay [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Harmsen, William [Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota (United States); Blanchard, Miran [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Goetz, Matthew [Division of Medical Oncology, Mayo Clinic, Rochester, Minnesota (United States); Jakub, James [Department of Surgery, Mayo Clinic, Rochester, Minnesota (United States); Mutter, Robert; Petersen, Ivy; Rooney, Jessica [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Stauder, Michael [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Yan, Elizabeth [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Laack, Nadia, E-mail: laack.nadia@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2014-08-01

    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

  18. 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.

  19. Radiation treatment for the right naris in a pediatric anesthesia patient using an adaptive oral airway technique

    Energy Technology Data Exchange (ETDEWEB)

    Sponseller, Patricia, E-mail: sponselp@uw.edu; Pelly, Nicole; Trister, Andrew; Ford, Eric; Ermoian, Ralph

    2015-10-01

    Radiation therapy for pediatric patients often includes the use of intravenous anesthesia with supplemental oxygen delivered via the nasal cannula. Here, we describe the use of an adaptive anesthesia technique for electron irradiation of the right naris in a preschool-aged patient treated under anesthesia. The need for an intranasal bolus plug precluded the use of standard oxygen supplementation. This novel technique required the multidisciplinary expertise of anesthesiologists, radiation therapists, medical dosimetrists, medical physicists, and radiation oncologists to ensure a safe and reproducible treatment course.

  20. [Ozone therapy for radiation reactions and skin lesions after neutron therapy in patients with malignant tumors].

    Science.gov (United States)

    Velikaya, V V; Gribova, O V; Musabaeva, L I; Startseva, Zh A; Simonov, K A; Aleinik, A N; Lisin, V A

    2015-01-01

    The article discusses the problem of radiation complications from normal tissues in patients after therapy with fast neutrons of 6.3 MeV. The methods of treatment using ozone technologies in patients with radiation reactions and skin lesions on the areas of irradiation after neutron and neutron-photon therapy have been worked out. Ozone therapy showed its harmlessness and increased efficiency of complex treatment of these patients.

  1. 21 CFR 892.5050 - Medical charged-particle radiation therapy system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Medical charged-particle radiation therapy system...-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy system...) intended for use in radiation therapy. This generic type of device may include signal analysis and display...

  2. [The application of total quality management (TQM) in quality management of radiation therapy].

    Science.gov (United States)

    Jiang, Rui-yao; Fu, Shen; Li, Bin

    2009-03-01

    The strategies and methods of the total quality management (TQM) need to applied in quality management of radiation therapy. We should improve the level of quality control and quality assurance in radiation therapy. By establishing quality control system in radiation therapy, standardization of radiation therapy workflow, strengthening quality control of devices and physical technique and paying attention to safety protection and staff training.

  3. Radiation-Induced Second Cancer Risk Estimates From Radionuclide Therapy

    Science.gov (United States)

    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.

  4. 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

  5. Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis

    Energy Technology Data Exchange (ETDEWEB)

    Miyazato, Tomonori; Yusa, Toshiko; Onaga, Tomohiro; Sugaya, Kimio; Koyama, Yuzo; Hatano, Tadashi; Ogawa, Yoshihide [Ryukyus Univ., Nishihara, Okinawa (Japan). Faculty of Medicine

    1998-05-01

    Radiation therapy has widely been used for cancers in the pelvis. Radiation cystitis, one of the late complications, presents often as hemorrhagic cystitis, which is refractory to the conventional therapy and may threaten the patient`s life. We used hyperbaric oxygen therapy on patients with radiation cystitis to test its potential benefit. Ten patients aged from 46 to 81 years with a mean of 62 years underwent one or more courses of hyperbaric oxygen therapy according to their symptoms, consisting of 20 sessions (3 to 5 sessions a week) at the Department of Hyperbaric Medicine, the University of the Ryukyus Hospital in the 9-year period from 1985 to 1994. They included 8 patients having a history of cervical cancer, one with external genital cancer and one with vaginal cancer. During the 75 min hyperbaric oxygen therapy patients received 100% oxygen at 2 absolute atmosphere pressure in the Multiplace Hyperbaric Chamber. Hematuria subsided and subjective symptoms including urinary frequency improved in seven patients. Cystoscopic findings including mucosal edema, redness, and capillary dilation were partially improved. The procedure subjectively and objectively palliated the 10 patients in a favorable manner. To date we have not armed any active procedure to control radiation-induced refractory hemorrhagic cystitis in terms of efficacy, invasiveness, and adverse effects. Therefore, in consideration of our clinical results, hyperbaric oxygen therapy appears to be useful for radiation cystitis. (author)

  6. Music therapy CD creation for initial pediatric radiation therapy: a mixed methods analysis.

    Science.gov (United States)

    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.

  7. 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.

  8. Deep reinforcement learning for automated radiation adaptation in lung cancer.

    Science.gov (United States)

    Tseng, Huan-Hsin; Luo, Yi; Cui, Sunan; Chien, Jen-Tzung; Ten Haken, Randall K; Naqa, Issam El

    2017-12-01

    To investigate deep reinforcement learning (DRL) based on historical treatment plans for developing automated radiation adaptation protocols for nonsmall cell lung cancer (NSCLC) patients that aim to maximize tumor local control at reduced rates of radiation pneumonitis grade 2 (RP2). In a retrospective population of 114 NSCLC patients who received radiotherapy, a three-component neural networks framework was developed for deep reinforcement learning (DRL) of dose fractionation adaptation. Large-scale patient characteristics included clinical, genetic, and imaging radiomics features in addition to tumor and lung dosimetric variables. First, a generative adversarial network (GAN) was employed to learn patient population characteristics necessary for DRL training from a relatively limited sample size. Second, a radiotherapy artificial environment (RAE) was reconstructed by a deep neural network (DNN) utilizing both original and synthetic data (by GAN) to estimate the transition probabilities for adaptation of personalized radiotherapy patients' treatment courses. Third, a deep Q-network (DQN) was applied to the RAE for choosing the optimal dose in a response-adapted treatment setting. This multicomponent reinforcement learning approach was benchmarked against real clinical decisions that were applied in an adaptive dose escalation clinical protocol. In which, 34 patients were treated based on avid PET signal in the tumor and constrained by a 17.2% normal tissue complication probability (NTCP) limit for RP2. The uncomplicated cure probability (P+) was used as a baseline reward function in the DRL. Taking our adaptive dose escalation protocol as a blueprint for the proposed DRL (GAN + RAE + DQN) architecture, we obtained an automated dose adaptation estimate for use at ∼2/3 of the way into the radiotherapy treatment course. By letting the DQN component freely control the estimated adaptive dose per fraction (ranging from 1-5 Gy), the DRL automatically favored dose

  9. Stereotactic body radiation therapy versus conventional radiation therapy in patients with early stage non-small cell lung cancer

    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....

  10. Optimization in Radiation Therapy: Applications in Brachytherapy and Intensity Modulated Radiation Therapy

    Science.gov (United States)

    McGeachy, Philip David

    Over 50% of cancer patients require radiation therapy (RT). RT is an optimization problem requiring maximization of the radiation damage to the tumor while minimizing the harm to the healthy tissues. This dissertation focuses on two main RT optimization problems: 1) brachytherapy and 2) intensity modulated radiation therapy (IMRT). The brachytherapy research involved solving a non-convex optimization problem by creating an open-source genetic algorithm optimizer to determine the optimal radioactive seed distribution for a given set of patient volumes and constraints, both dosimetric- and implant-based. The optimizer was tested for a set of 45 prostate brachytherapy patients. While all solutions met the clinical standards, they also benchmarked favorably with those generated by a standard commercial solver. Compared to its compatriot, the salient features of the generated solutions were: slightly reduced prostate coverage, lower dose to the urethra and rectum, and a smaller number of needles required for an implant. Historically, IMRT requires modulation of fluence while keeping the photon beam energy fixed. The IMRT-related investigation in this thesis aimed at broadening the solution space by varying photon energy. The problem therefore involved simultaneous optimization of photon beamlet energy and fluence, denoted by XMRT. Formulating the problem as convex, linear programming was applied to obtain solutions for optimal energy-dependent fluences, while achieving all clinical objectives and constraints imposed. Dosimetric advantages of XMRT over single-energy IMRT in the improved sparing of organs at risk (OARs) was demonstrated in simplified phantom studies. The XMRT algorithm was improved to include clinical dose-volume constraints and clinical studies for prostate and head and neck cancer patients were investigated. Compared to IMRT, XMRT provided improved dosimetric benefit in the prostate case, particularly within intermediate- to low-dose regions (≤ 40 Gy

  11. 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.)

  12. 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.

  13. Invasions, adaptive radiations, and the generation of biodiversity

    Directory of Open Access Journals (Sweden)

    John C. Briggs

    2014-03-01

    Full Text Available When the subject of global biodiversity and its loss through human action became a focal point of conservation biology, there developed an increasing argument about the effects of the invasions of exotic species into native ecosystems. In order to place the current contention in a historical context, evidence from the geologic record has been examined. The record clearly indicates that numerous species invasions, extending from the Paleozoic through the Cenozoic, have led to adaptive radiations significantly increasing global biodiversity. Three invasion induced categories are recognized: (1 global radiations, (2 local radiations, and (3 single species effects. Together, the three may account for much of the biodiversity gain that has accumulated in the intervals between mass extinctions. In contemporary time, it has become apparent that exotic species colonizing a native ecosystem rarely cause extinctions. Instead, the invaders are accommodated by the native species that occupy the appropriate niches or habitats. The accommodation process results in a gain in the species diversity of the invaded area. Over time, local diversity gains can result in global gains as speciation among the invaders takes place. The majority of successful invasions occur via migration of species from centers of high species diversity to places of lesser diversity. The result is a dynamic world characterized by constant movement whereby the high diversity centers increase the diversity of outlying regions.

  14. Deformable image registration in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Seung Jong; Kim, Si Yong [Dept. of Radiation Oncology, Virginia Commonwealth University, Richmond (United States)

    2017-06-15

    The number of imaging data sets has significantly increased during radiation treatment after introducing a diverse range of advanced techniques into the field of radiation oncology. As a consequence, there have been many studies proposing meaningful applications of imaging data set use. These applications commonly require a method to align the data sets at a reference. Deformable image registration (DIR) is a process which satisfies this requirement by locally registering image data sets into a reference image set. DIR identifies the spatial correspondence in order to minimize the differences between two or among multiple sets of images. This article describes clinical applications, validation, and algorithms of DIR techniques. Applications of DIR in radiation treatment include dose accumulation, mathematical modeling, automatic segmentation, and functional imaging. Validation methods discussed are based on anatomical landmarks, physical phantoms, digital phantoms, and per application purpose. DIR algorithms are also briefly reviewed with respect to two algorithmic components: similarity index and deformation models.

  15. Method and devices for performing stereotactic microbeam radiation therapy

    Science.gov (United States)

    Dilmanian, F. Avraham

    2010-01-05

    A radiation delivery system generally includes either a synchrotron source or a support frame and a plurality of microbeam delivery devices supported on the support frame, both to deliver a beam in a hemispherical arrangement. Each of the microbeam delivery devices or synchrotron irradiation ports is adapted to deliver at least one microbeam of radiation along a microbeam delivery axis, wherein the microbeam delivery axes of the plurality of microbeam delivery devices cross within a common target volume.

  16. Modern radiation therapy for extranodal lymphomas

    DEFF Research Database (Denmark)

    Yahalom, Joachim; Illidge, Tim; Specht, Lena

    2015-01-01

    adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other......, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far...

  17. [Personnel requirements of medical radiation physics in radiotherapy in comparison to the current guidelines "radiation protection in medicine" : Special consideration of intensity-modulated radiation therapy].

    Science.gov (United States)

    Leetz, H-K; Eipper, H H; Gfirtner, H; Schneider, P; Welker, K

    2014-08-01

    In 1994 and 1998 reports on staffing levels in medical radiation physics for radiation therapy were published by the "Deutsche Gesellschaft für Medizinische Physik" (DGMP, German Society for Medical Physics). Because of the technical and methodological progress, changes in recommended qualifications of staff and new governmental regulations, it was necessary to establish new staffing levels. The data were derived from a new survey in clinics. Some of the previously established results from the old reports were adapted to the new conditions by conversion.The staffing requirements were normalized to main components as in the earlier reports resulting in a simple method for calculation of staffing levels. The results were compared with the requirements in the "Richtlinie Strahlenschutz in der Medizin" (guidelines on radiation protection in medicine) and showed satisfactory agreement.

  18. Communication skills training for radiation therapists: preparing patients for radiation therapy.

    Science.gov (United States)

    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

  19. Optical tomography for measuring dose distribution in radiation therapy

    Directory of Open Access Journals (Sweden)

    Kauppinen Matti

    2014-01-01

    Full Text Available The dosimetry is used to verify the dose magnitude with artificial samples (phantoms before giving the planned radiation therapy to the patient. Typically, dose distribution is measured only in a single point or on a two-dimensional matrix plane. New techniques of radiation therapy ensure more detailed planning of radiation dose distribution which will lead to the need of measuring the radiation dose distribution three-dimensionally. The gel dosimetry is used to indicate and determine the ionizing radiation three-dimensionally. The radiation causes changes in chemical properties of the gel. The radiation dose distribution is defined by measuring the chemical changes. A conventional method is the magnetic resonance imaging and a new possibility is optical computed tomography (optical-CT. The optical-CT is much cheaper and more practical than magnetic resonance imaging. In this project, an optical-CT based method device was built by aiming at low material costs and a simple realization. The constructed device applies the charge coupled device camera and fluorescent lamp technologies. The test results show that the opacity level of the radiated gel can be measured accurately enough. The imaging accuracy is restricted by the optical distortion, e. g. vignetting, of the lenses, the distortion of a fluorescent lamp as the light source and a noisy measuring environment.

  20. Risk Factors for Pelvic Insufficiency Fractures in Locally Advanced Cervical Cancer Following Intensity Modulated Radiation Therapy

    DEFF Research Database (Denmark)

    Ramlov, Anne; Pedersen, Erik Morre; Røhl, Lisbeth

    2017-01-01

    and underwent external beam radiation therapy with 45 Gy in 25 fractions (node-negative patients) or 50 Gy in 25 fractions with a simultaneous integrated boost of 60 Gy in 30 fractions (node-positive patients). Pulsed dose rate magnetic resonance imaging guided adaptive brachytherapy was given in addition......PURPOSE: To investigate the incidence of and risk factors for pelvic insufficiency fracture (PIF) after definitive chemoradiation therapy for locally advanced cervical cancer (LACC). METHODS AND MATERIALS: We analyzed 101 patients with LACC treated from 2008-2014. Patients received weekly cisplatin...

  1. Two Effective Heuristics for Beam Angle Optimization in Radiation Therapy

    CERN Document Server

    Yarmand, Hamed

    2013-01-01

    In radiation therapy, mathematical methods have been used for optimizing treatment planning for delivery of sufficient dose to the cancerous cells while keeping the dose to critical surrounding structures minimal. This optimization problem can be modeled using mixed integer programming (MIP) whose solution gives the optimal beam orientation as well as optimal beam intensity. The challenge, however, is the computation time for this large scale MIP. We propose and investigate two novel heuristic approaches to reduce the computation time considerably while attaining high-quality solutions. We introduce a family of heuristic cuts based on the concept of 'adjacent beams' and a beam elimination scheme based on the contribution of each beam to deliver the dose to the tumor in the ideal plan in which all potential beams can be used simultaneously. We show the effectiveness of these heuristics for intensity modulated radiation therapy (IMRT) and stereotactic body radiation therapy (SBRT) on a clinical liver case.

  2. Determinants of job satisfaction among radiation therapy faculty.

    Science.gov (United States)

    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.

  3. Image-guided radiation therapy for treatment delivery and verification

    Science.gov (United States)

    Schubert, Leah Kayomi

    Target conformity and normal tissue sparing provided by modern radiation therapy techniques often result in steep dose gradients, which increase the need for more accurate patient setup and treatment delivery. Image guidance is starting to play a major role in determining the accuracy of treatment setup. A typical objective of image-guided radiation therapy (IGRT) is to minimize differences between planned and delivered treatment by imaging the patient prior to delivery. This step verifies and corrects for patient setup and is referred to as setup verification. This dissertation evaluates the efficacy of daily imaging for setup verification and investigates new uses of IGRT for potential improvements in treatment delivery. The necessity of daily imaging can first be determined by assessing differences in setup corrections between patient groups. Therefore, the first objective of this investigation was to evaluate the application of IGRT for setup verification by quantifying differences in patient positioning for several anatomical disease sites. Detailed analysis of setup corrections for brain, head and neck, lung, and prostate treatments is presented. In this analysis, large setup errors were observed for prostate treatments. Further assessment of prostate treatments was performed, and patient-specific causes of setup errors investigated. Setup corrections are applied via rigid shifts or rotations of the patient or machine, but anatomical deformations occur for which rigid shifts cannot correct. Fortunately, IGRT provides images on which anatomical changes occurring throughout the course of treatment can be detected. From those images, the efficacy of IGRT in ensuring accurate treatment delivery can be evaluated and improved by determining delivered doses and adapting the plan during treatment. The second objective of this dissertation was to explore new applications of IGRT to further improve treatment. By utilizing daily IGRT images, a retrospective analysis of

  4. Hypofractionated radiation therapy versus conventional radiation therapy in prostate cancer: A systematic review of its safety and efficacy.

    Science.gov (United States)

    Sánchez-Gómez, L M; Polo-deSantos, M; Rodríguez-Melcón, J I; Angulo, J C; Luengo-Matos, S

    2015-01-01

    New therapeutic alternatives can improve the safety and efficacy of prostate cancer treatment. To assess whether hypofractionated radiation therapy results in better safety and efficacy in the treatment of prostate cancer. Systematic review of the literature through searches on PubMed, Cochrane Library, CRD, ClinicalTrials and EuroScan, collecting indicators of safety and efficacy. We included 2 systematic reviews and a clinical trial. In terms of efficacy, there is considerable heterogeneity among the studies, and no conclusive results were found concerning the superiority of the hypofractionated option over the normal fractionated option. In terms of safety, there were no significant differences in the onset of acute genitourinary complications between the 2 treatments. However, one of the reviews found more acute gastrointestinal complications in patients treated with hypofractionated radiation therapy. There were no significant differences in long-term complications based on the type of radiation therapy used, although the studies did have limitations. To date, there are no conclusive results that show that hypofractionated radiation therapy is more effective or safer than normal fractionated radiation therapy in the treatment of localized prostate cancer. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Current status of radiation therapy. Evidence-based medicine (EBM) of radiation therapy. Non-small cell lung cancer (NSCLC)

    Energy Technology Data Exchange (ETDEWEB)

    Sumi, Minako [National Cancer Center, Tokyo (Japan). Hospital

    2002-04-01

    The goal of radiation therapy for non-small cell lung cancer (NSCLC) is to improve the survival rate of patients without increasing treatment-related toxicity and to improve patients' quality of life. Several prospective randomized trials have demonstrated a survival advantage in combined modality treatment over radiotherapy or chemotherapy alone when a cisplatin-based chemotherapy regimen is utilized in the treatment plan. Combined modality treatment of cisplatin-based chemotherapy and radiotherapy is standard treatment for selected patients such as those with better performance status with locally or regionally advanced lung cancer including T3-T4 or N2-N3. Determining the contribution of new agents in combined modality treatment will require carefully designed and conducted clinical trials. High-dose involved field radiation therapy using 3D-conformal radiation therapy potentially enables the use of higher doses than standard radiation therapy, because less normal tissue is irradiated, and may improve local control and survival. The combination of radiotherapy with chemotherapy and dose escalation using 3D-conformal radiation therapy is also a possibility in unresectable NSCLC. In surgery cases, the results of several Phase III trials of cisplatin-based preoperative chemotherapy have suggested survival improvement. But the concept needs to be tested in a larger Phase III trial. (author)

  6. The physical basis and future of radiation therapy

    Science.gov (United States)

    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

  7. The physical basis and future of radiation therapy.

    Science.gov (United States)

    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.

  8. Synchrotron Radiation Therapy from a Medical Physics point of view

    Science.gov (United States)

    Prezado, Y.; Adam, J. F.; Berkvens, P.; Martinez-Rovira, I.; Fois, G.; Thengumpallil, S.; Edouard, M.; Vautrin, M.; Deman, P.; Bräuer-Krisch, E.; Renier, M.; Elleaume, H.; Estève, F.; Bravin, A.

    2010-07-01

    Synchrotron radiation (SR) therapy is a promising alternative to treat brain tumors, whose management is limited due to the high morbidity of the surrounding healthy tissues. Several approaches are being explored by using SR at the European Synchrotron Radiation Facility (ESRF), where three techniques are under development Synchrotron Stereotactic Radiation Therapy (SSRT), Microbeam Radiation Therapy (MRT) and Minibeam Radiation Therapy (MBRT). The sucess of the preclinical studies on SSRT and MRT has paved the way to clinical trials currently in preparation at the ESRF. With this aim, different dosimetric aspects from both theoretical and experimental points of view have been assessed. In particular, the definition of safe irradiation protocols, the beam energy providing the best balance between tumor treatment and healthy tissue sparing in MRT and MBRT, the special dosimetric considerations for small field dosimetry, etc will be described. In addition, for the clinical trials, the definition of appropiate dosimetry protocols for patients according to the well established European Medical Physics recommendations will be discussed. Finally, the state of the art of the MBRT technical developments at the ESRF will be presented. In 2006 A. Dilmanian and collaborators proposed the use of thicker microbeams (0.36-0.68 mm). This new type of radiotherapy is the most recently implemented technique at the ESRF and it has been called MBRT. The main advantage of MBRT with respect to MRT is that it does not require high dose rates. Therefore it can be more easily applied and extended outside synchrotron sources in the future.

  9. Translation and adaptation procedures for music therapy outcome instruments

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner; McDermott, Orii; Orrell, Martin

    2017-01-01

    With increasing occurrence of international multicentre studies, there is a need for music therapy outcome measures to become more widely available across countries. For countries where English is not the first language, translation and cross-cultural adaptation of outcome measures may be necessary....... A literature review identified a knowledge gap regarding translation procedures of outcome measures used in music therapy research. However, a large body of translation guidelines is available in other health professions. We used the guidelines from these related fields to identify guidelines and outline...... procedural steps for the translation and adaptation of music therapy outcome instruments. OBS: 50 free online copies to share: http://www.tandfonline.com/eprint/d8TPZbkVMjzgKg7DjcmT/full...

  10. Current status of radiation therapy. Evidence-based medicine (EBM) of radiation therapy. Current management of patients with esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Nemoto, Kenji [Tohoku Univ., Sendai (Japan). School of Medicine

    2002-03-01

    The best management for small mucosal esophageal cancer is generally endoscopic mucosal resection. However, for submucosal cancer and extensive mucosal caner, either radical surgery or radiation seems to be an equally efficacious option. Radiation therapy concurrent with chemotherapy is more effective than radiation therapy alone for patients with unresectable esophageal cancer. The key drugs are cisplatin and 5-fluorouracil. However, for patients with poor performance status or for aged patients, radiation therapy alone is still a choice of treatment. Surgery has generally been indicated for patients with resectable esophageal cancer. However, outcomes of concurrent chemoradiation therapy may be comparable with those of surgery. Therefore, a prospective randomized study should be performed to determine the best management for patients with resectable esophageal cancer. The usefulness of intra-cavitary irradiation for esophageal cancer has not been clarified. A prospective randomized trial with a large number of patients is necessary to determine the effectiveness of intra-cavitary irradiation. The best management for patients with loco-regionally recurrent esophageal cancer after surgery has not been determined. Intensive therapy should be considered if the site of recurrence is limited and the time interval from surgery to recurrence is long. Chemotherapy is essential in the management of patients with small cell esophageal cancer. However, the best local therapy has not been determined. (author)

  11. Complications of head and neck radiation therapy and their management

    Energy Technology Data Exchange (ETDEWEB)

    Engelmeier, R.L.; King, G.E.

    1983-04-01

    Patients who receive radiation therapy to the head and neck suffer potential complications and undesirable side-effects of this therapy. The extent of undesirable responses is dependent on the source of irradiation, the fields of irradiation, and the dose. The radiotherapist determines these factors by the extent, location, and radiosensitivity of the tumor. The potential undesirable side-effects are xerostomia, mucositis, fibrosis, trismus, dermatitis, photosensitivity, radiation caries, soft tissue necrosis, and osteoradionecrosis. Each of these clinical entities and their proposed management have been discussed.

  12. Khan's lectures handbook of the physics of radiation therapy

    CERN Document Server

    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

  13. Novel Silicon Devices for Radiation Therapy Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bruzzi, Mara, E-mail: mara.bruzzi@unifi.it

    2016-02-11

    Modern radiotherapy techniques pose specific constraints in radiation-monitoring and dosimetry due to the occurrence of small radiation fields with high dose gradients, variation in space and time of the dose rate, variation in space and time of the beam energy spectrum. Novel devices coping with these strict conditions are needed. This paper reviews the most advanced technologies developed with silicon-based materials for clinical radiotherapy. Novel Si diodes as Pt-doped Si, epitaxial Si as well as thin devices have optimized performance, their response being independent of the accumulated dose, thus ensuring radiation tolerance and no need of recalibration. Monolithic devices based on segmented Si detectors can be easily tailored to optimize spatial resolution in the large active areas required in clinical radiotherapy. In particular, a monolithic device based on epitaxial p-type silicon, characterized by high spatial resolution and ability to directly measure temporal variations in dose modulation proved to be best viable solution for pre-treatment verifications in IMRT fields.

  14. 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

  15. Adaptive phenotypic plasticity in the Midas cichlid fish pharyngeal jaw and its relevance in adaptive radiation

    Directory of Open Access Journals (Sweden)

    Salzburger Walter

    2011-04-01

    Full Text Available Abstract Background Phenotypic evolution and its role in the diversification of organisms is a central topic in evolutionary biology. A neglected factor during the modern evolutionary synthesis, adaptive phenotypic plasticity, more recently attracted the attention of many evolutionary biologists and is now recognized as an important ingredient in both population persistence and diversification. The traits and directions in which an ancestral source population displays phenotypic plasticity might partly determine the trajectories in morphospace, which are accessible for an adaptive radiation, starting from the colonization of a novel environment. In the case of repeated colonizations of similar environments from the same source population this "flexible stem" hypothesis predicts similar phenotypes to arise in repeated subsequent radiations. The Midas Cichlid (Amphilophus spp. in Nicaragua has radiated in parallel in several crater-lakes seeded by populations originating from the Nicaraguan Great Lakes. Here, we tested phenotypic plasticity in the pharyngeal jaw of Midas Cichlids. The pharyngeal jaw apparatus of cichlids, a second set of jaws functionally decoupled from the oral ones, is known to mediate ecological specialization and often differs strongly between sister-species. Results We performed a common garden experiment raising three groups of Midas cichlids on food differing in hardness and calcium content. Analyzing the lower pharyngeal jaw-bones we find significant differences between diet groups qualitatively resembling the differences found between specialized species. Observed differences in pharyngeal jaw expression between groups were attributable to the diet's mechanical resistance, whereas surplus calcium in the diet was not found to be of importance. Conclusions The pharyngeal jaw apparatus of Midas Cichlids can be expressed plastically if stimulated mechanically during feeding. Since this trait is commonly differentiated - among

  16. Immunomodulatory effects of radiation: what is next for cancer therapy?

    Science.gov (United States)

    Kumari, Anita; Simon, Samantha S; Moody, Tomika D; Garnett-Benson, Charlie

    2016-01-01

    Despite its former reputation as being immunosuppressive, it has become evident that radiation therapy can enhance antitumor immune responses. This quality can be harnessed by utilizing radiation as an adjuvant to cancer immunotherapies. Most studies combine the standard radiation dose and regimens indicated for the given disease state, with novel cancer immunotherapies. It has become apparent that low-dose radiation, as well as doses within the hypofractionated range, can modulate tumor cells making them better targets for immune cell reactivity. Herein, we describe the range of phenotypic changes induced in tumor cells by radiation, and explore the diverse mechanisms of immunogenic modulation reported at these doses. We also review the impact of these doses on the immune cell function of cytotoxic cells in vivo and in vitro.

  17. Adaptive radiation of multituberculate mammals before the extinction of dinosaurs.

    Science.gov (United States)

    Wilson, Gregory P; Evans, Alistair R; Corfe, Ian J; Smits, Peter D; Fortelius, Mikael; Jernvall, Jukka

    2012-03-14

    The Cretaceous-Paleogene mass extinction approximately 66 million years ago is conventionally thought to have been a turning point in mammalian evolution. Prior to that event and for the first two-thirds of their evolutionary history, mammals were mostly confined to roles as generalized, small-bodied, nocturnal insectivores, presumably under selection pressures from dinosaurs. Release from these pressures, by extinction of non-avian dinosaurs at the Cretaceous-Paleogene boundary, triggered ecological diversification of mammals. Although recent individual fossil discoveries have shown that some mammalian lineages diversified ecologically during the Mesozoic era, comprehensive ecological analyses of mammalian groups crossing the Cretaceous-Paleogene boundary are lacking. Such analyses are needed because diversification analyses of living taxa allow only indirect inferences of past ecosystems. Here we show that in arguably the most evolutionarily successful clade of Mesozoic mammals, the Multituberculata, an adaptive radiation began at least 20 million years before the extinction of non-avian dinosaurs and continued across the Cretaceous-Paleogene boundary. Disparity in dental complexity, which relates to the range of diets, rose sharply in step with generic richness and disparity in body size. Moreover, maximum dental complexity and body size demonstrate an adaptive shift towards increased herbivory. This dietary expansion tracked the ecological rise of angiosperms and suggests that the resources that were available to multituberculates were relatively unaffected by the Cretaceous-Paleogene mass extinction. Taken together, our results indicate that mammals were able to take advantage of new ecological opportunities in the Mesozoic and that at least some of these opportunities persisted through the Cretaceous-Paleogene mass extinction. Similar broad-scale ecomorphological inventories of other radiations may help to constrain the possible causes of mass extinctions.

  18. Stereotactic radiation therapy and selective internal radiation therapy for hepatocellular carcinoma; Radiotherapie stereotaxique et radiotherapie interne selective du carcinome hepatocellulaire

    Energy Technology Data Exchange (ETDEWEB)

    Bujold, A.; Dawson, L.A. [Radiation Medicine Program, Princess Margaret Hospital, 610, University Avenue, Toronto M5G 2C1 (Canada)

    2011-02-15

    Recent technological advances allow precise and safe radiation delivery in hepatocellular carcinoma. Stereotactic body radiotherapy is a conformal external beam radiation technique that uses a small number of relatively large fractions to deliver potent doses of radiation therapy to extracranial sites. It requires stringent breathing motion control and image guidance. Selective internal radiotherapy or radio-embolization refers to the injection of radioisotopes, usually delivered to liver tumors via the hepatic artery. Clinical results for both treatments show that excellent local control is possible with acceptable toxicity. Most appropriate patient populations and when which type of radiation therapy should be best employed in the vast therapeutic armamentarium of hepatocellular carcinoma are still to be clarified. (authors)

  19. Postoperative radiation therapy for malignant glioma. Results of conventional radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Teshima, T.; Inoue, T.; Chatani, M.; Hata, K.; Taki, T.; Nii, Y.; Nakagawa, H.

    1987-02-01

    From December 1977 through September 1984, a total of 39 cases of malignant glioma were treated with radiation therapy (RT) postoperatively. Twenty-nine cases were classified into glioblastoma (GM) and 10 astrocytoma (AS) (low grade : 6 and anaplastic : 4) histologically. One third of cases received 50 Gy/25 FRX/5 WKS of whole brain RT. Another two thirds of cases underwent 60 Gy/30 FRX/6 WKS of whole brain or 50 Gy/25 FRX/5 WKS of whole brain + additional 20 Gy/10 FRX/2 WKS of localized field RT. Chemotherapy (BLM, MeCCNU and ACNU) was given for 34 cases. Survivals at 3 years for GM and AS were 12 % and 68 %, respectively. Prognostic factors for GM were age, neurologic function (RTOG), AJC-staging T-factor, pre-RT LDH level and volume of residual tumor. Corresponding factors for AS were histological subclassification and neurologic function (RTOG). However, RT dose and field did not impact on survival significantly. Acute adverse effects of RT were otitis media or externa (70 %) and conjunctivitis (8 %). Retinal bleeding was noted in three long-term survivors at 2 years after RT.

  20. Phenytoin Induced Erythema Multiforme after Cranial Radiation Therapy.

    Science.gov (United States)

    Kazanci, Atilla; Tekkök, İsmail Hakkı

    2015-08-01

    The prophylactic use of phenytoin during and after brain surgery and cranial irradiation is a common measure in brain tumor therapy. Phenytoin has been associated with variety of adverse skin reactions including urticaria, erythroderma, erythema multiforme (EM), Stevens-Johnson syndrome, and toxic epidermal necrolysis. EM associated with phenytoin and cranial radiation therapy (EMPACT) is a rare specific entity among patients with brain tumors receiving radiation therapy while on prophylactic anti-convulsive therapy. Herein we report a 41-year-old female patient with left temporal glial tumor who underwent surgery and then received whole brain radiation therapy and chemotherapy. After 24 days of continous prophylactic phenytoin therapy the patient developed minor skin reactions and 2 days later the patient returned with generalized erythamatous and itchy maculopapuler rash involving neck, chest, face, trunk, extremities. There was significant periorbital and perioral edema. Painful mucosal lesions consisting of oral and platal erosions also occurred and prevented oral intake significantly. Phenytoin was discontinued gradually. Systemic admistration of corticosteroids combined with topical usage of steroids for oral lesions resulted in complete resolution of eruptions in 3 weeks. All cutaneous lesions in patients with phenytoin usage with the radiotherapy must be evoluated with suspicion for EM.

  1. Long Term Results of Radiation Therapy in Early Glottic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Hee; Byun, Sang Jun [Dongsan Medical Center, Daegu (Korea, Republic of)

    2009-03-15

    This study was designed to evaluate long-term results in terms of failure, survival and voice preservation after radiation therapy for early glottic cancer. From February 1988 to December 2003, 70 patients with early glottic cancer were treated with radiation therapy at Keimyung University Dongsan Medical Center. Patient age distribution was from 39 to 79 years, with a median age of 62 years. All patients had squamous cell carcinoma. According to the TNM stage, 58 patients had stage I disease, 12 patients had stage II disease; 67 patients were male. The laryngeal area was irradiated with the use of bilateral opposing fields with/without a wedge filter with 6 MV photons at a total dose of 54{approx}70.2 Gy in 1.8{approx}2.2 Gy fractions over 6{approx}8 weeks. We delivered a median radiation dose of 60 Gy for stage I patients and a median radiation dose of 66 Gy for stage II patients. Salvage surgery was performed in patients with local recurrence. The voice preservation rate was analyzed after all treatments including salvage surgery. Follow-up periods were from 13 to 180 months, with a median follow-up period of 77.5 months. The survival rate was analyzed by the use of the Kaplan Meier method and log rank test. A comparison of two groups was performed with the use of the chi-squared test. The local control rate was 98.5% (69/70). The five-year-overall survival rate was 93.9%. The five-year disease free survival rate (5YDFS) was 84.1% and the 5YDFS after radiation and salvage surgery was 92.8%. According to stage, the 5YDFS was 93.1% and 91.7% for stage I and stage II respectively. Thirteen patients (18.5%) had local failure with 24 months of median time to local failure and nine patients received salvage surgery; however, four patients were lost to follow-up after a diagnosis of recurrence. Only two patients died due to a distant metastasis at 33 months and 71 months after radiation therapy, respectively. Nine patients died due to other diseases with a median time

  2. Salvage radiation therapy following radical prostatectomy

    DEFF Research Database (Denmark)

    Ervandian, Maria; Høyer, Morten; Petersen, Stine Elleberg

    2016-01-01

    .0%. Nearly half of the patients (44%) received androgen deprivation therapy (ADT) in combination with SRT. Positive surgical tumour margins (p = 0.025) and ADT (p = 0.001) were the only markers independently correlated with b-PFS. In patients who received SRT without ADT, both a pre-SRT PSA level ≤0.5 ng...

  3. Maxillary sinus carcinoma: result of radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Shibuya, H.; Horiuchi, J.; Suzuki, S.; Shioda, S.; Enomoto, S.

    1984-07-01

    This hundred and sixteen patients with carcinoma of the maxillary sinus received primary therapy consisting of external beam irradiation alone or in combination with surgery and/or chemotherapy at the Department of Radiology, Tokyo Medical and Dental University Hospital, between 1953 and 1982. In our institution, methods of treating cancer of the maxillary sinus have been changed from time to time and showed different control rates and clinical courses. An actuarial 10-year survival rate of 21% has been obtained by the megavoltage irradiation alone as well as 34% actuarial 10-year survival rate by megavoltage irradiation with surgery. After the introduction of conservative surgery followed by conventional trimodal combination therapy, the local control rate has been improved. The amount of functional, cosmetic, and brain damages have been remarkably decreased by this mode of therapy. The actuarial five year survival rate was 67%. In addition, along with the improvement of the local control rate, the control of nodal and distant organ metastases have been emerging as one of the important contributions to the prognosis of this disease.

  4. Complications after radiation therapy for cervical carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, M. (Iwate Medical Coll., Morioka (Japan). School of Medicine)

    1981-04-01

    From 1966 to 1973, 215 patients with cervical cancer were treated at the Department of Obstetrics and Gynecology, School of Medicine, Iwate Medical University. The patients were divided into two groups. In the first group, 123 patients were treated by external radiation with Tele-/sup 60/Co plus radium insertions (1966-1970). In the second group, 83 patients were treated with linear accelerator plus cesium insertions (1970-1973). The results on both of 5-year survival rate and appearance of radiation injuries were compared with in the two groups. There was no significant difference in the cure rate between those groups. The incidence of pigmentation, edema and diarrhea (early complications) was higher and the diarrhea continued significantly longer in the second group. The incidence of rectal ulcer and rectostenosis (later complications) was significantly higher than former group. A study was made to learn the reason for the significantly higher occurrence of rectal ulcer and rectostenosis. As a result, it was determined that later complication was more emphasized especially by dose rate of intracavitary irradiation. In addition, it is thought that the dose rate, the dose volume and natural history such as the patients' age are also related to the severity of the complications.

  5. BRCA1 Mutation: A Predictive Marker for Radiation Therapy?

    Energy Technology Data Exchange (ETDEWEB)

    Kan, Charlene; Zhang, Junran, E-mail: Junran.zhang@case.edu

    2015-10-01

    DNA repair, in particular, DNA double-strand break (DSB) repair, is essential for the survival of both normal and cancer cells. An elaborate repair mechanism has been developed in cells to efficiently repair the damaged DNA. The pathways predominately involved in DSB repair are homologous recombination and classic nonhomologous end-joining, although the alternative NHEJ pathway, a third DSB repair pathway, could also be important in certain contexts. The protein of BRCA1 encoded by the tumor suppressor gene BRCA1 regulates all DSB repair pathways. Given that DSBs represent the most biologically significant lesions induced by ionizing radiation and that impaired DSB repair leads to radiation sensitivity, it has been expected that cancer patients with BRCA1 mutations should benefit from radiation therapy. However, the clinical data have been conflicting and inconclusive. We provide an overview about the current status of the data regarding BRCA1 deficiency and radiation therapy sensitivity in both experimental models and clinical investigations. In addition, we discuss a strategy to potentiate the effects of radiation therapy by poly(ADP-ribose) polymerase inhibitors, the pharmacologic drugs being investigated as monotherapy for the treatment of patients with BRCA1/2 mutations.

  6. 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.

  7. The role of radiation therapy in epithelial ovarian cancer | Dreyer ...

    African Journals Online (AJOL)

    The role of radiation therapy in epithelial ovarian cancer. G Dreyer. Abstract. No Abstract. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL ...

  8. A maximum feasible subset algorithm with application to radiation therapy

    DEFF Research Database (Denmark)

    Sadegh, Payman

    1999-01-01

    . The algorithm relies on an iterative constraint removal procedure where constraints are eliminated from a set proposed by solutions to minmax linear programs. The method is illustrated by a simulated example of a linear system with double sided bounds and a case from the area of radiation therapy....

  9. Baroreflex failure following radiation therapy for nasopharyngeal carcinoma

    NARCIS (Netherlands)

    Timmers, H. J.; Karemaker, J. M.; Lenders, J. W.; Wieling, W.

    1999-01-01

    The authors present a 51-year-old man with right-sided nasopharyngeal carcinoma who was treated for regional lymph node involvement by bilateral radiation therapy of the neck. Six years later he presented with episodic complaints of headache, flushing, and palpitations accompanied by elevations of

  10. Gastrointestinal Toxicities With Combined Antiangiogenic and Stereotactic Body Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Pollom, Erqi L.; Deng, Lei [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Pai, Reetesh K. [Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Brown, J. Martin; Giaccia, Amato; Loo, Billy W.; Shultz, David B.; Le, Quynh Thu; Koong, Albert C. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Chang, Daniel T., E-mail: dtchang@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States)

    2015-07-01

    Combining the latest targeted biologic agents with the most advanced radiation technologies has been an exciting development in the treatment of cancer patients. Stereotactic body radiation therapy (SBRT) is an ablative radiation approach that has become established for the treatment of a variety of malignancies, and it has been increasingly used in combination with biologic agents, including those targeting angiogenesis-specific pathways. Multiple reports have emerged describing unanticipated toxicities arising from the combination of SBRT and angiogenesis-targeting agents, particularly of late luminal gastrointestinal toxicities. In this review, we summarize the literature describing these toxicities, explore the biological mechanism of action of toxicity with the combined use of antiangiogenic therapies, and discuss areas of future research, so that this combination of treatment modalities can continue to be used in broader clinical contexts.

  11. Intraoperative radiation therapy for noncuratively resected pancreatic carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Atsutake; Tsuruta, Kohji; Tabata, Ikuo; Isawa, Tomoaki; Kamisawa, Terumi; Tanaka, Yoshiaki (Tokyo Metropolitan Komagome Hospital (Japan))

    1992-08-01

    The effect of intraoperative radiation therapy (IORT) was studied in 20 patients with noncuratively resected pancreatic carcinoma. Seventeen out of the 20 patients also received external beam radiation therapy (EBRT) by conformation radiation. The IORT targets were the retroperitoneal tissues, such as lymph vessels, nerve plexuses around the SMA and the wall of the SMV where macroscopic or microscopic residual might remain. The one-, and 2 year survival rates were 52.6%, and 10.5%, respectively, with a median survival of 12.1 months, in 19 patients excluding one operative death. These survival rates were not significantly different from those in 30 patients with unresectable tumors treated by IORT in combination with EBRT, though their tumor conditions were more advanced. From these, the treatment with IORT plus EBRT should be useful for patients with advanced disease, avoiding aggressive tumor resection, if tumor resection becomes noncurative. At present, we approach to evaluate possible effects of IORT for curative tumor resection. (author).

  12. Radiation therapy-associated invasive bladder tumors

    Energy Technology Data Exchange (ETDEWEB)

    Sella, A.; Dexeus, F.H.; Chong, C.; Ro, J.Y.; Logothetis, C.J.

    1989-03-01

    Radiotherapy-associated bladder carcinoma was found in 3.7 percent of 244 cases of advanced urothelial carcinoma. Average age at diagnosis of the bladder tumor was 63.1 years, with a mean of 20.5 years between radiation treatment and diagnosis. All 9 patients presented with gross hematuria. Eight patients had transitional cell carcinoma, 7/8 (87.5%) also had vascular or lymphatic invasion, and 1 was adenocarcinoma. Mean survival was 15.4 months (range 1-40 mos.), with a 55.5 percent one-year disease-free survival after diagnosis. Four patients died of bladder tumor, 4 were alive with no evidence of disease, and 1 was alive with metastasis.

  13. Effects of dopaminergic therapy on locomotor adaptation and adaptive learning in persons with Parkinson's disease.

    Science.gov (United States)

    Roemmich, Ryan T; Hack, Nawaz; Akbar, Umer; Hass, Chris J

    2014-07-15

    Persons with Parkinson's disease (PD) are characterized by multifactorial gait deficits, though the factors which influence the abilities of persons with PD to adapt and store new gait patterns are unclear. The purpose of this study was to investigate the effects of dopaminergic therapy on the abilities of persons with PD to adapt and store gait parameters during split-belt treadmill (SBT) walking. Ten participants with idiopathic PD who were being treated with stable doses of orally-administered dopaminergic therapy participated. All participants performed two randomized testing sessions on separate days: once while optimally-medicated (ON meds) and once after 12-h withdrawal from dopaminergic medication (OFF meds). During each session, locomotor adaptation was investigated as the participants walked on a SBT for 10 min while the belts moved at a 2:1 speed ratio. We assessed locomotor adaptive learning by quantifying: (1) aftereffects during de-adaptation (once the belts returned to tied speeds immediately following SBT walking) and (2) savings during re-adaptation (as the participants repeated the same SBT walking task after washout of aftereffects following the initial SBT task). The withholding of dopaminergic medication diminished step length aftereffects significantly during de-adaptation. However, both locomotor adaptation and savings were unaffected by levodopa. These findings suggest that dopaminergic pathways influence aftereffect storage but do not influence locomotor adaptation or savings within a single session of SBT walking. It appears important that persons with PD should be optimally-medicated if walking on the SBT as gait rehabilitation. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Oxygenation of spontaneous canine tumors during fractionated radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Achermann, R.E.; Ohlerth, S.M.; Bley, C.R.; Inteeworn, N.; Schaerz, M.; Wergin, M.C.; Kaser-Hotz, B. [Section of Diagnostic Imaging and Radiation Oncology, Veterinary School, Univ. of Zurich (Switzerland); Gassmann, M. [Inst. for Veterinary Physiology, Univ. of Zurich (Switzerland); Roos, M. [Inst. for Social and Preventive Medicine, Univ. of Zurich (Switzerland)

    2004-05-01

    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{sub 2}) measurements were performed with the eppendorf-pO{sub 2}-Histograph. The measurements were done under general anesthesia, and probe tracks were guided with ultrasound. pO{sub 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{sub 2} {<=} 10 mmHg. The pO{sub 2} values appeared to be quite variable in individual tumors during fractionated radiation therapy. The pO{sub 2} of initially hypoxic tumors (pretreatment median pO{sub 2} {<=} 10 mmHg) remained unchanged during fractionated radiotherapy, whereas in initially normoxic tumors the pO{sub 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.)

  15. The Results of Postoperative Radiation Therapy in the Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Ja [Ewha Womans University College of Medicine, Seoul (Korea, Republic of)

    1994-02-15

    Purpose: Despite apparently complete resection of cancer of the rectum, local recurrence rate was high. Radiation therapy has been used either alone or in combination with chemotherapy as an adjunct to surgery to reduce the risk of recurrence. This study was designed to evaluate the prognostic factors, survival rate and local recurrence rate of the rectal cancer who had received postoperative radiation therapy by retrospective analysis. Method: From 1982 to 1990, 63 patients with cancer of the rectum surgically staged as B2 or C disease received postoperative adjuvant radiation therapy after curative resection of tumor for cure. Postoperative radiation therapy was given to the whole pelvis (mean dose: 5040 cGy in 5-6weeks) and perineum was included in irradiated field in case of abdominoperineal resection. Results: Three-year actuarial survival rate was 73.2% overall, 87.7% in stage B2+3 and 62.9% in stage C2+3. Three-year disease-free survival rate was 69.5% overall, 87.7% in stage B2+3 and 56.8% in stage C2+3. Three-year disease-free survival rate in anterior resection was 77.8% and 44.4% in abdominoperineal resection. The local recurrence rate was 15.9% and distant failure rate was 20.6%. Severe late complication was small bowel obstruction in 6 patients and surgery was required in 4 patients (6.3%). The prognostic factors were stage (p=0.0221) and method of surgery(p=0.0414) (anterior resection vs abdominoperineal resection). Conclusion: This study provides evidence supporting the use of postoperative radiation therapy for reducing the local recurrence rate in patients who have had curative resection of rectal cancer with involvement of perirectal fat or regional nodes or both (stage B2 and C)

  16. Modern Radiation Therapy and Cardiac Outcomes in Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Boero, Isabel J.; Paravati, Anthony J.; Triplett, Daniel P.; Hwang, Lindsay; Matsuno, Rayna K.; Gillespie, Erin F.; Yashar, Catheryn M.; Moiseenko, Vitali; Einck, John P.; Mell, Loren K. [Department of Radiation Medicine and Applied Sciences, Moores Cancer Center, University of California, San Diego, La Jolla, California (United States); Parikh, Sahil A. [University Hospitals Case Medical Center, Harrington Heart and Vascular Institute, and Case Western Reserve University School of Medicine, Cleveland, Ohio (United States); Murphy, James D., E-mail: j2murphy@ucsd.edu [Department of Radiation Medicine and Applied Sciences, Moores Cancer Center, University of California, San Diego, La Jolla, California (United States)

    2016-03-15

    Purpose: Adjuvant radiation therapy, which has proven benefit against breast cancer, has historically been associated with an increased incidence of ischemic heart disease. Modern techniques have reduced this risk, but a detailed evaluation has not recently been conducted. The present study evaluated the effect of current radiation practices on ischemia-related cardiac events and procedures in a population-based study of older women with nonmetastatic breast cancer. Methods and Materials: A total of 29,102 patients diagnosed from 2000 to 2009 were identified from the Surveillance, Epidemiology, and End Results–Medicare database. Medicare claims were used to identify the radiation therapy and cardiac outcomes. Competing risk models were used to assess the effect of radiation on these outcomes. Results: Patients with left-sided breast cancer had a small increase in their risk of percutaneous coronary intervention (PCI) after radiation therapy—the 10-year cumulative incidence for these patients was 5.5% (95% confidence interval [CI] 4.9%-6.2%) and 4.5% (95% CI 4.0%-5.0%) for right-sided patients. This risk was limited to women with previous cardiac disease. For patients who underwent PCI, those with left-sided breast cancer had a significantly increased risk of cardiac mortality with a subdistribution hazard ratio of 2.02 (95% CI 1.23-3.34). No other outcome, including cardiac mortality for the entire cohort, showed a significant relationship with tumor laterality. Conclusions: For women with a history of cardiac disease, those with left-sided breast cancer who underwent radiation therapy had increased rates of PCI and a survival decrement if treated with PCI. The results of the present study could help cardiologists and radiation oncologists better stratify patients who need more aggressive cardioprotective techniques.

  17. From dinosaurs to modern bird diversity: extending the time scale of adaptive radiation.

    Science.gov (United States)

    Moen, Daniel; Morlon, Hélène

    2014-05-01

    What explains why some groups of organisms, like birds, are so species rich? And what explains their extraordinary ecological diversity, ranging from large, flightless birds to small migratory species that fly thousand of kilometers every year? These and similar questions have spurred great interest in adaptive radiation, the diversification of ecological traits in a rapidly speciating group of organisms. Although the initial formulation of modern concepts of adaptive radiation arose from consideration of the fossil record, rigorous attempts to identify adaptive radiation in the fossil record are still uncommon. Moreover, most studies of adaptive radiation concern groups that are less than 50 million years old. Thus, it is unclear how important adaptive radiation is over temporal scales that span much larger portions of the history of life. In this issue, Benson et al. test the idea of a "deep-time" adaptive radiation in dinosaurs, compiling and using one of the most comprehensive phylogenetic and body-size datasets for fossils. Using recent phylogenetic statistical methods, they find that in most clades of dinosaurs there is a strong signal of an "early burst" in body-size evolution, a predicted pattern of adaptive radiation in which rapid trait evolution happens early in a group's history and then slows down. They also find that body-size evolution did not slow down in the lineage leading to birds, hinting at why birds survived to the present day and diversified. This paper represents one of the most convincing attempts at understanding deep-time adaptive radiations.

  18. A Conceptual and Statistical Framework for Adaptive Radiations with a Key Role for Diversity Dependence

    NARCIS (Netherlands)

    Etienne, Rampal S.; Haegeman, Bart

    2012-01-01

    In this article we propose a new framework for studying adaptive radiations in the context of diversity-dependent diversification. Diversity dependence causes diversification to decelerate at the end of an adaptive radiation but also plays a key role in the initial pulse of diversification. In

  19. Ecological and evolutionary determinants for the adaptive radiation of the Madagascan vangas

    NARCIS (Netherlands)

    Jonsson, Knud A.; Fabre, Pierre-Henri; Fritz, Susanne A.; Etienne, Rampal S.; Ricklefs, Robert E.; Jorgensen, Tobias B.; Fjeldsa, Jon; Rahbek, Carsten; Ericson, Per G. P.; Woog, Friederike; Pasquet, Eric; Irestedt, Martin

    2012-01-01

    Adaptive radiation is the rapid diversification of a single lineage into many species that inhabit a variety of environments or use a variety of resources and differ in traits required to exploit these. Why some lineages undergo adaptive radiation is notwell-understood, but filling unoccupied

  20. Occurrence of BOOP outside radiation field after tangential radiation therapy for breast carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Hamanishi, Tohru; Gohma, Iwao; Oida, Kazukiyo [Tenri Hospital, Nara (Japan)] (and others)

    2000-07-01

    We report three cases of bronchiolitis obliterans organizing pneumonia (BOOP) that occurred outside the radiation field after radiation therapy using tangential fields for breast carcinoma. All patients complained of a cough between 14 and 20 weeks after completion of radiation therapy. Fever also developed in two of the three. Chest radiography and computed tomography demonstrated peripheral alveolar opacities outside the radiation field on the same side as the radiation therapy. Laboratory data showed an increased level of C-reactive protein and an increased erythrocyte sedimentation rate. Bronchoalveolar lavage showed an elevated total cell count with a very high percentage of lymphocytes. Transbronchial lung biopsy revealed a histologic pattern consistent with BOOP. Treatment with corticosteroids resulted in rapid clinical improvement and complete resolution of the radiographic abnormalities. This pulmonary disorder appears to be induced by radiation, especially when a tangential field is employed for breast carcinoma, though the etiology has not been fully investigated. It is important to be aware of this type of pulmonary complication in patients given radiotherapy for breast carcinoma. (author)

  1. Intricacies of Feedback in Computer-based Prism Adaptation Therapy

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; Rytter, Hana Malá

    Prism Adaptation Therapy (PAT) is an intervention method for treatment of attentional disorders, such as neglect e.g. 1,2. The method involves repeated pointing at specified targets with or without prism glasses using a specifically designed wooden box. The aim of this study was to ascertain...... of visuospatial disorders.     1. Rossetti et al. Nature 1998, 395: 166-169 2. Frassinetti et al. Brain 2002, 125: 608-623...

  2. Hyperbaric oxygen therapy for delayed radiation injuries in gynecological cancers.

    Science.gov (United States)

    Fink, D; Chetty, N; Lehm, J P; Marsden, D E; Hacker, N F

    2006-01-01

    Delayed radiation-induced injuries are difficult to treat. The treatment of delayed radiation injuries with hyperbaric oxygen therapy (HBOT) is reported in small case series and case reports. This study reports the experience of a single institution with HBOT in delayed radiation injuries in patients with gynecological cancers. At least 20 sessions of 100% oxygen inhalation at 2.4 Atmospheric Absolutes (ATA) for 90 min in a hyperbaric chamber were carried out. Of the 14 patients included in the study, 10 patients have healed or showed improvement of more than 50%, resulting in a success rate of 71%. Mean follow-up was 31.6 months (range 6-70 months). The adverse events were acceptable. HBOT should be considered for patients with delayed radiation injuries, not responding to other treatments.

  3. Manifestation pattern of early-late vaginal morbidity after definitive radiation (chemo)therapy and image-guided adaptive brachytherapy for locally advanced cervical cancer: an analysis from the EMBRACE study

    NARCIS (Netherlands)

    Kirchheiner, Kathrin; Nout, Remi A.; Tanderup, Kari; Lindegaard, Jacob C.; Westerveld, Henrike; Haie-Meder, Christine; Petrič, Primož; Mahantshetty, Umesh; Dörr, Wolfgang; Pötter, Richard

    2014-01-01

    Brachytherapy in the treatment of locally advanced cervical cancer has changed substantially because of the introduction of combined intracavitary/interstitial applicators and an adaptive target concept, which is the focus of the prospective, multi-institutional EMBRACE study (www.embracestudy.dk)

  4. Treatment of thoracic wounds with adapted vacuum therapy

    Directory of Open Access Journals (Sweden)

    Igor Renato L.B. de Abreu

    2014-01-01

    Full Text Available This is a report of seven cases of infected thoracic wounds treated with an adapted low-cost vacuum therapy in the Thoracic Surgery Unit of Santa Marcelina Hospital. The vacuum system used was designed and adapted to our hospital due to financial limitations on the acquisition of commercial kits. The vacuum-assisted closure kit used in this study consisted of chlorhexidine sponges (which are usually used for antisepsis of the surgical team, a 16F nasogastric tube, and two sterile adhesive films (OPSITE for surgical field reinforcement. The mean duration of vacuum therapy was 13.4 days (range, 10–20 days, with an average of three dressing changes (range, 1–5. After treatment with vacuum-assisted closure, three wounds (3/7 were closed with simple primary sutures, one of the lesions (1/7 was closed by muscle flap rotation, and three wounds (3/7 healed by second intention. This adapted vacuum therapy was safe and easy to apply in our institution, including its use in patients with thoracostomies.

  5. Molecular investigation of genetic assimilation during the rapid adaptive radiations of East African cichlid fishes.

    Science.gov (United States)

    Gunter, Helen M; Schneider, Ralf F; Karner, Immanuel; Sturmbauer, Christian; Meyer, Axel

    2017-12-01

    Adaptive radiations are characterized by adaptive diversification intertwined with rapid speciation within a lineage resulting in many ecologically specialized, phenotypically diverse species. It has been proposed that adaptive radiations can originate from ancestral lineages with pronounced phenotypic plasticity in adaptive traits, facilitating ecologically driven phenotypic diversification that is ultimately fixed through genetic assimilation of gene regulatory regions. This study aimed to investigate how phenotypic plasticity is reflected in gene expression patterns in the trophic apparatus of several lineages of East African cichlid fishes, and whether the observed patterns support genetic assimilation. This investigation used a split brood experimental design to compare adaptive plasticity in species from within and outside of adaptive radiations. The plastic response was induced in the crushing pharyngeal jaws through feeding individuals either a hard or soft diet. We find that nonradiating, basal lineages show higher levels of adaptive morphological plasticity than the derived, radiated lineages, suggesting that these differences have become partially genetically fixed during the formation of the adaptive radiations. Two candidate genes that may have undergone genetic assimilation, gif and alas1, were identified, in addition to alterations in the wiring of LPJ patterning networks. Taken together, our results suggest that genetic assimilation may have dampened the inducibility of plasticity related genes during the adaptive radiations of East African cichlids, flattening the reaction norms and canalizing their feeding phenotypes, driving adaptation to progressively more narrow ecological niches. © 2017 John Wiley & Sons Ltd.

  6. What to Know about Brachytherapy (A Type of Internal Radiation Therapy)

    Science.gov (United States)

    N ational C ancer I nstitute Understanding Radiation Therapy What To Know About Brachytherapy (A Type of Internal Radiation Therapy) “I asked questions. My doctor took the time to help my family ...

  7. Scope of nanotechnology-based radiation therapy and thermotherapy methods in cancer treatment.

    Science.gov (United States)

    Bakht, Mohamadreza K; Sadeghi, Mahdi; Pourbaghi-Masouleh, Milad; Tenreiro, Claudio

    2012-10-01

    The main aim of nanomedicine is to revolutionize the health care system and find effective approaches to fighting fatal diseases. Therapeutic beams, which are employed in radiation therapy, do not discriminate between normal and cancerous cells and must rely on targeting the radiation beams to specific cells. Interestingly, the application of nanoscale particles in radiation therapy has aimed to improve outcomes in radiation therapy by increasing toxicity in tumors and reducing it in normal tissues. This review focuses on approaches to nanotechnology-based cancer radiation therapy methods such as radionuclide therapy, photodynamic therapy, and neutron capture therapy. Moreover, we have investigated nanotechnology-based thermotherapy methods, including hyperthermia and thermoablation, as non-ionizing modalities of treatment using thermal radiation. The results strongly demonstrate that nanotechnology-based cancer radiation therapy and thermotherapy methods hold substantial potential to improve the efficacy of anticancer radiation and thermotherapy modalities.

  8. The ecology of a continental evolutionary radiation: Is the radiation of sigmodontine rodents adaptive?

    Science.gov (United States)

    Maestri, Renan; Monteiro, Leandro Rabello; Fornel, Rodrigo; Upham, Nathan S; Patterson, Bruce D; de Freitas, Thales Renato Ochotorena

    2017-03-01

    Evolutionary radiations on continents are less well-understood and appreciated than those occurring on islands. The extent of ecological influence on species divergence can be evaluated to determine whether a radiation was ultimately the outcome of divergent natural selection or else arose mainly by nonecological divergence. Here, we used phylogenetic comparative methods to test distinct hypotheses corresponding to adaptive and nonadaptive evolutionary scenarios for the morphological evolution of sigmodontine rodents. Results showed that ecological variables (diet and life-mode) explain little of the shape and size variation of sigmodontine skulls and mandibles. A Brownian model with varying rates for insectivory versus all other diets was the most likely evolutionary model. The insectivorous sigmodontines have a faster rate of morphological evolution than mice feeding on other diets, possibly due to stronger selection for features that aid insectivory. We also demonstrate that rapid early-lineage diversification is not accompanied by high morphological divergence among subclades, contrasting with island results. The geographic size of continents permits spatial segregation to a greater extent than on islands, allowing for allopatric distributions and escape from interspecific competition. We suggest that continental radiations of rodents are likely to produce a pattern of high species diversification coupled with a low degree of phenotypic specialization. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  9. Anaemia and radiation therapy; Anemie et radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Denis, F. [Clinique d' Oncologie et de Radiotherapie, INSERM U619, 37 - Tours (France); Lartigau, E. [Centre de Lutte Contre le Cancer Oscar-Lambret, Dept. de Radiotherapie, 59 - Lille (France)

    2004-11-01

    Anaemia is frequent in cancer and may increase tumour hypoxia that stimulates angiogenesis. However, erythropoietin is a hypoxia-inducible stimulator of erythropoiesis which seems to improve quality of life in cancer patients. Two recent phase III randomized studies showed negative results using erythropoietin in head and neck cancer patients and in metastatic breast cancer patients with impaired specific survival. In vitro and in vivo experiments have provided erythropoietin-receptor expression in endothelial cancer cells including malignant tumours of the breast, prostate, cervix, lung, head and neck, ovary, melanoma, stomach, gut, kidney etc. Biologic effect of erythropoietin and its receptor linkage induces proliferation of human breast cancer and angiogenesis and may limit anti-tumour effect of cancer treatment, in part, by tumour vascularization improvement. In addition, the use of exogenous erythropoietin could be able to favour tumour progression by improving tumour oxygenation and nutriment supply. If erythropoietin receptor were functional in human cancer. the assessment of erythropoietin receptor expression on tumour cell may help to select patients benefiting from exogenous erythropoietin. However. the relationship between erythropoietin receptor expression, tumour growth and exogenous erythropoietin. requires more studies. The results of recent clinical trials suggest that using erythropoietin should be avoided in non-anemic patients and discussed in patients receiving curative therapy. (authors)

  10. Three dimensional conformal radiation therapy may improve the therapeutic ratio of radiation therapy after pneumonectomy for lung cancer

    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.

  11. 42 CFR Appendix F to Part 75 - Standards for Licensing Radiographers, Nuclear Medicine Technologists, and Radiation Therapy...

    Science.gov (United States)

    2010-10-01

    ... Medicine Technologists, and Radiation Therapy Technologists F Appendix F to Part 75 Public Health PUBLIC..., and Radiation Therapy Technologists The following section describes basic elements to be incorporated... licensed as Radiographers, Nuclear Medicine Technologists, or Radiation Therapy Technologists. 2. Licenses...

  12. 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.

  13. Radiation therapy in the treatment of metastatic renal cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Onufrey, V.; Mohiuddin, M.

    1985-11-01

    Adenocarcinoma of the kidney is an unusual tumor, both in its biological behavior and in its response to radiation treatment. Historically, these tumors have been considered to be radioresistant, and the role of radiation therapy remains questionable in the primary management of this disease. However, radiation treatment is routinely used in the palliation of metastatic lesions for relief of symptoms. Therefore, we have undertaken a review of our experience in the treatment of this disease to determine the effectiveness of radiation in its palliation. From 1956 to 1981, 125 patients with metastatic lesions from hypernephroma have been treated in the Department of Radiation Therapy at Thomas Jefferson University Hospital. Most patients were referred for relief of bone pain (86), brain metastasis (12), spinal cord compression (9), and soft tissue masses (18). Total doses varied from 2000 rad to a maximum of 6000 rad. Response to treatment was evaluated on the basis of relief of symptoms, either complete, partial or no change. Our results indicate a significantly higher response rate of 65% for total doses equal to or greater than a TDF of 70, as compared to 25% for doses lower than a TDF of 70. No difference in response was observed either for bone or soft tissue metastasis or visceral disease. This leads us to believe that metastatic lesions from adenocarcinomas of the kidney should be treated to higher doses to obtain maximum response rates. Analysis of these results are presented in detail.

  14. Hybrid Adaptive Ray-Moment Method (HARM2): A highly parallel method for radiation hydrodynamics on adaptive grids

    Science.gov (United States)

    Rosen, A. L.; Krumholz, M. R.; Oishi, J. S.; Lee, A. T.; Klein, R. I.

    2017-02-01

    We present a highly-parallel multi-frequency hybrid radiation hydrodynamics algorithm that combines a spatially-adaptive long characteristics method for the radiation field from point sources with a moment method that handles the diffuse radiation field produced by a volume-filling fluid. Our Hybrid Adaptive Ray-Moment Method (HARM2) operates on patch-based adaptive grids, is compatible with asynchronous time stepping, and works with any moment method. In comparison to previous long characteristics methods, we have greatly improved the parallel performance of the adaptive long-characteristics method by developing a new completely asynchronous and non-blocking communication algorithm. As a result of this improvement, our implementation achieves near-perfect scaling up to O (103) processors on distributed memory machines. We present a series of tests to demonstrate the accuracy and performance of the method.

  15. Immunotherapy and radiation therapy for malignant pleural mesothelioma

    Science.gov (United States)

    Katz, Sharyn I.; Cengel, Keith A.; Simone, Charles B.

    2017-01-01

    Malignant pleural mesothelioma (MPM) is a particularly aggressive thoracic malignancy with limited survival following combination chemotherapy. As a result, there has been increased interested in immunotherapy for mesothelioma, both in the first-line and salvage settings. Early investigations of interleukin-2 (IL-2) and interferon alfa-2a/b have been limited by modest response rates and toxicity, whereas cytokine gene therapy is currently being investigated and shows early promise. The most prominent class of immunotherapies to be trialed with mesothelioma in the past half-decade has been immune checkpoint inhibitors (CPI). Early results are encouraging, particularly for agents targeting the PD-1/PD-L1 pathways. With the increasing recognition of the immune potential of mesothelioma, interest in the immunomodulatory properties of radiation therapy has emerged. The combination of immunotherapy and radiation therapy may allow for complimentary immunologic effects that can enhance antitumor response. This article reviews the existing literature on the efficacy of immunotherapy for MPM, describes the rationale for combining immunotherapy with radiation therapy, and discusses early literature on this treatment combination. PMID:28529903

  16. Gold Nanoparticles and Their Alternatives for Radiation Therapy Enhancement

    Directory of Open Access Journals (Sweden)

    Daniel R. Cooper

    2014-10-01

    Full Text Available Radiation therapy is one of the most commonly used treatments for cancer. The dose of delivered ionizing radiation can be amplified by the presence of high-Z materials via an enhancement of the photoelectric effect; the most widely studied material is gold (atomic number 79. However, a large amount is needed to obtain a significant dose enhancement, presenting a challenge for delivery. In order to make this technique of broader applicability, the gold must be targeted, or alternative formulations developed that do not rely solely on the photoelectric effect. One possible approach is to excite scintillating nanoparticles with ionizing radiation, and then exploit energy transfer between these particles and attached dyes in a manner analogous to photodynamic therapy. Doped rare-earth halides and semiconductor quantum dots have been investigated for this purpose. However, although the spectrum of emitted light after radiation excitation is usually similar to that seen with light excitation, the yield is not. Measurement of scintillation yields is challenging, and in many cases has been done only for bulk materials, with little understanding of how the principles translate to the nanoscale. Another alternative is to use local heating using gold or iron, followed by application of ionizing radiation. Hyperthermia pre-sensitizes the tumors, leading to an improved response. Another approach is to use chemotherapeutic drugs that can radiosensitize tumors. Drugs may be attached to high-Z nanoparticles or encapsulated. This article discusses each of these techniques, giving an overview of the current state of nanoparticle-assisted radiation therapy and future directions.

  17. Cranial shape evolution in adaptive radiations of birds: comparative morphometrics of Darwin's finches and Hawaiian honeycreepers

    OpenAIRE

    Tokita, Masayoshi; Yano, Wataru; James, Helen F.; Abzhanov, Arhat

    2017-01-01

    Adaptive radiation is the rapid evolution of morphologically and ecologically diverse species from a single ancestor. The two classic examples of adaptive radiation are Darwin's finches and the Hawaiian honeycreepers, which evolved remarkable levels of adaptive cranial morphological variation. To gain new insights into the nature of their diversification, we performed comparative three-dimensional geometric morphometric analyses based on X-ray microcomputed tomography (µCT) scanning of dried ...

  18. Cryptic adaptive radiation in tropical forest trees in New Caledonia.

    Science.gov (United States)

    Pillon, Yohan; Hopkins, Helen C F; Rigault, Frédéric; Jaffré, Tanguy; Stacy, Elizabeth A

    2014-04-01

    The causes of the species richness of tropical trees are poorly understood, in particular the roles of ecological factors such as soil composition. The nickel(Ni)-hyperaccumulating tree genus Geissois (Cunoniaceae) from the South-west Pacific was chosen as a model of diversification on different substrates. Here, we investigated the leaf element compositions, spatial distributions and phylogeny of all species of Geissois occurring on New Caledonia. We found that New Caledonian Geissois descended from a single colonist and diversified relatively quickly into 13 species. Species on ultramafic and nonultramafic substrates showed contrasting patterns of leaf element composition and range overlap. Those on nonultramafic substrates were largely sympatric but had distinct leaf element compositions. By contrast, species on ultramafic substrates showed similar leaf element composition, but occurred in many cases exclusively in allopatry. Further, earlier work showed that at least three out of these seven species use different molecules to bind Ni. Geissois qualifies as a cryptic adaptive radiation, and may be the first such example in a lineage of tropical forest trees. Variation in biochemical strategies for coping with both typical and adverse soil conditions may help to explain the diversification and coexistence of tropical forest trees on similar soil types. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  19. Adaptive introgression from distant Caribbean islands contributed to the diversification of a microendemic adaptive radiation of trophic specialist pupfishes.

    Directory of Open Access Journals (Sweden)

    Emilie J Richards

    2017-08-01

    Full Text Available Rapid diversification often involves complex histories of gene flow that leave variable and conflicting signatures of evolutionary relatedness across the genome. Identifying the extent and source of variation in these evolutionary relationships can provide insight into the evolutionary mechanisms involved in rapid radiations. Here we compare the discordant evolutionary relationships associated with species phenotypes across 42 whole genomes from a sympatric adaptive radiation of Cyprinodon pupfishes endemic to San Salvador Island, Bahamas and several outgroup pupfish species in order to understand the rarity of these trophic specialists within the larger radiation of Cyprinodon. 82% of the genome depicts close evolutionary relationships among the San Salvador Island species reflecting their geographic proximity, but the vast majority of variants fixed between specialist species lie in regions with discordant topologies. Top candidate adaptive introgression regions include signatures of selective sweeps and adaptive introgression of genetic variation from a single population in the northwestern Bahamas into each of the specialist species. Hard selective sweeps of genetic variation on San Salvador Island contributed 5 times more to speciation of trophic specialists than adaptive introgression of Caribbean genetic variation; however, four of the 11 introgressed regions came from a single distant island and were associated with the primary axis of oral jaw divergence within the radiation. For example, standing variation in a proto-oncogene (ski known to have effects on jaw size introgressed into one San Salvador Island specialist from an island 300 km away approximately 10 kya. The complex emerging picture of the origins of adaptive radiation on San Salvador Island indicates that multiple sources of genetic variation contributed to the adaptive phenotypes of novel trophic specialists on the island. Our findings suggest that a suite of factors

  20. 21 CFR 892.5900 - X-ray radiation therapy system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false X-ray radiation therapy system. 892.5900 Section... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5900 X-ray radiation therapy system. (a) Identification. An x-ray radiation therapy system is a device intended to produce and control x...

  1. 21 CFR 892.5710 - Radiation therapy beam-shaping block.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiation therapy beam-shaping block. 892.5710... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5710 Radiation therapy beam-shaping block. (a) Identification. A radiation therapy beam-shaping block is a device made of a highly...

  2. 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.

  3. Accreditation and quality assurance for Radiation Therapy Oncology Group: Multicenter clinical trials using Stereotactic Body Radiation Therapy in lung cancer.

    Science.gov (United States)

    Timmerman, Robert; Galvin, James; Michalski, Jeff; Straube, William; Ibbott, Geoffrey; Martin, Elizabeth; Abdulrahman, Ramzi; Swann, Suzanne; Fowler, Jack; Choy, Hak

    2006-01-01

    Starting in 2002, the Radiation Therapy Oncology Group in North America began the process of developing multicenter prospective trials in lung cancer using Stereotactic Body Radiation Therapy (SBRT). Much of the work was based on the prospective single institution trials from Indiana University that had been presented and published. In late 2004, RTOG 0236 using SBRT for medically inoperable patients with clinical stage I non-small cell lung cancer (NSCLC) was activated for accrual. Prior to activation, representatives from the Lung, Image-Guided Therapy, Physics, and Radiobiology Committees met on regular occasions to design the multicenter study and quality assurance measures. SBRT is not a black box, and the essence of the therapy had to be distilled via guidelines. Issues related to patient selection, method of dosimetry construction, equipment requirements, motion assessments and control, site accreditation, data exchange, and follow-up policies were worked out by compromise and consensus. RTOG 0236 has nearly completed its accrual. The Lung Committee has initiated the development of several other trials, each building on the last, to investigate the therapy in central tumors, in combinations with systemic therapy, in operable patients, and in lung metastases patients. The guidelines developed for RTOG 0236 will be refined to take advantage of more modern innovations including heterogeneity corrections and intensity modulation when appropriate. The development of RTOG 0618 using SBRT in operable patients with early stage NSCLC is a testament to both the enthusiasm from already published works and prospective multicenter clinical testing using SBRT techniques.

  4. Adjuvant and Salvage Radiation Therapy After Prostatectomy: American Society for Radiation Oncology/American Urological Association Guidelines

    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.

  5. The consequence of day-to-day stochastic dose deviation from the planned dose in fractionated radiation therapy.

    Science.gov (United States)

    Paul, Subhadip; Roy, Prasun Kumar

    2016-02-01

    Radiation therapy is one of the important treatment procedures of cancer. The day-to-day delivered dose to the tissue in radiation therapy often deviates from the planned fixed dose per fraction. This day-to-day variation of radiation dose is stochastic. Here, we have developed the mathematical formulation to represent the day-to-day stochastic dose variation effect in radiation therapy. Our analysis shows that that the fixed dose delivery approximation under-estimates the biological effective dose, even if the average delivered dose per fraction is equal to the planned dose per fraction. The magnitude of the under-estimation effect relies upon the day-to-day stochastic dose variation level, the dose fraction size and the values of the radiobiological parameters of the tissue. We have further explored the application of our mathematical formulation for adaptive dose calculation. Our analysis implies that, compared to the premise of the Linear Quadratic Linear (LQL) framework, the Linear Quadratic framework based analytical formulation under-estimates the required dose per fraction necessary to produce the same biological effective dose as originally planned. Our study provides analytical formulation to calculate iso-effect in adaptive radiation therapy considering day-to-day stochastic dose deviation from planned dose and also indicates the potential utility of LQL framework in this context.

  6. Accounting for radiation quality in heavy ion therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kellerer, A.M. [LMU, Muenchen (Germany). Radiobiological Inst.]|[Gesellschaft fuer Strahlen- und Umweltforschung, Muenchen (Germany). Inst. fuer Nuklearbiologie

    1997-09-01

    This introductory contribution outlines the need for models and their use in radiotherapy dose planning. The linear-quadratic dose relation is now predominantly used in therapy dose planning. In Section I it is linked to the earlier quantitative scheme for conventional radiotherapy. In Section II two major approaches are presented in a form that makes them comparable; the section can be read by itself, if this comparison alone is of interest. Models for therapy planning are tools, largely of empirical character; they do not need to elucidate unknown mechanisms of radiation action. The emphasis is, therefore, on the computational scheme, not on its interpretation. (orig.)

  7. Ultrasound motion tracking for radiation therapy; Ultraschallbewegungstracking fuer die Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Jenne, J. [Fraunhofer-Institut fuer Bildgestuetzte Medizin MEVIS, Bremen (Germany); Mediri GmbH, Heidelberg (Germany); Schwaab, J. [Mediri GmbH, Heidelberg (Germany)

    2015-11-15

    In modern radiotherapy the radiation dose can be applied with an accuracy in the range of 1-2 mm provided that the exact position of the target is known. If, however, the target (the tumor) is located in the lungs or the abdomen, respiration or peristalsis can cause substantial movement of the target. Various methods for intrafractional motion detection and compensation are currently under consideration or are already applied in clinical practice. Sonography is one promising option, which is now on the brink of clinical implementation. Ultrasound is particularly suited for this purpose due to the high soft tissue contrast, real-time capability, the absence of ionizing radiation and low acquisition costs. Ultrasound motion tracking is an image-based approach, i.e. the target volume or an adjacent structure is directly monitored and the motion is tracked automatically on the ultrasound image. Diverse algorithms are presently available that provide the real-time target coordinates from 2D as well as 3D images. Definition of a suitable sonographic window is not, however, trivial and a gold standard for positioning and mounting of the transducer has not yet been developed. Furthermore, processing of the coordinate information in the therapy unit and the dynamic adaptation of the radiation field are challenging tasks. It is not clear whether ultrasound motion tracking will become established in the clinical routine although all technical prerequisites can be considered as fulfilled, such that exciting progress in this field of research is still to be expected. (orig.) [German] In der modernen Strahlentherapie kann die Dosis mit einer Genauigkeit von 1-2 mm appliziert werden, sofern die Position der Zielstruktur genau bekannt ist. Liegt diese Zielstruktur (der Tumor) jedoch in der Lunge oder im Abdomen, koennen u. a. die Atmung oder die Peristaltik zu einer substanziellen Bewegung des Zielvolumens fuehren. Verschiedene Methoden zur intrafraktionellen Bewegungsdetektion

  8. Carcinoma of the anal canal: Intensity modulated radiation therapy (IMRT) versus three-dimensional conformal radiation therapy (3DCRT)

    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.

  9. Stereotactic body radiation therapy for metastasis to the adrenal glands.

    Science.gov (United States)

    Shiue, Kevin; Song, Andrew; Teh, Bin S; Ellis, Rodney J; Yao, Min; Mayr, Nina A; Huang, Zhibin; Sohn, Jason; Machtay, Mitchell; Lo, Simon S

    2012-12-01

    Many primary cancers can metastasize to the adrenal glands. Adrenalectomy via an open or laparoscopic approach is the current definitive treatment, but not all patients are eligible or wish to undergo surgery. There are only limited studies on the use of conventional radiation therapy for palliation of symptoms from adrenal metastasis. However, the advent of stereotactic body radiation therapy (SBRT) - also named stereotactic ablative radiotherapy for primary lung cancer, metastases to the lung, and metastases to the liver - have prompted some investigators to consider the use of SBRT for metastases to the adrenal glands. This review focuses on the emerging data on SBRT of metastasis to the adrenal glands, while also providing a brief discussion of the overall management of adrenal metastasis.

  10. 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......, planning parameters, and estimated doses to the critical organs at risk (OARs). METHODS: Ten patients with stage I-II classic HL with masses of different sizes and locations were selected. On the basis of the clinical information, 5 ILROG centers were asked to create RT plans to a prescribed dose of 30...

  11. Palliative care and palliative radiation therapy education in radiation oncology: A survey of US radiation oncology program directors.

    Science.gov (United States)

    Wei, Randy L; Colbert, Lauren E; Jones, Joshua; Racsa, Margarita; Kane, Gabrielle; Lutz, Steve; Vapiwala, Neha; Dharmarajan, Kavita V

    The purpose of this study was to assess the state of palliative and supportive care (PSC) and palliative radiation therapy (RT) educational curricula in radiation oncology residency programs in the United States. We surveyed 87 program directors of radiation oncology residency programs in the United States between September 2015 and November 2015. An electronic survey on PSC and palliative RT education during residency was sent to all program directors. The survey consisted of questions on (1) perceived relevance of PSC and palliative RT to radiation oncology training, (2) formal didactic sessions on domains of PSC and palliative RT, (3) effective teaching formats for PSC and palliative RT education, and (4) perceived barriers for integrating PSC and palliative RT into the residency curriculum. A total of 57 responses (63%) was received. Most program directors agreed or strongly agreed that PSC (93%) and palliative radiation therapy (99%) are important competencies for radiation oncology residents and fellows; however, only 67% of residency programs had formal educational activities in principles and practice of PSC. Most programs had 1 or more hours of formal didactics on management of pain (67%), management of neuropathic pain (65%), and management of nausea and vomiting (63%); however, only 35%, 33%, and 30% had dedicated lectures on initial management of fatigue, assessing role of spirituality, and discussing advance care directives, respectively. Last, 85% of programs reported having a formal curriculum on palliative RT. Programs were most likely to have education on palliative radiation to brain, bone, and spine, but less likely on visceral, or skin, metastasis. Residency program directors believe that PSC and palliative RT are important competencies for their trainees and support increasing education in these 2 educational domains. Many residency programs have structured curricula on PSC and palliative radiation education, but room for improvement exists in

  12. Effects of radiation therapy on growing long bones

    Energy Technology Data Exchange (ETDEWEB)

    De Smet, A.A.; Kuhns, L.R.; Fayos, J.V.; Holt, J.F.

    1976-12-01

    Characteristic radiographic changes were seen in six of 14 children who received radiation therapy to the epiphyseal plate of a long bone. These changes, which include metaphyseal sclerosis, metaphyseal fraying, and epiphyseal plate widening, resemble rickets. In three patients, these changes were followed by development of a broad metaphyseal band of increased density. The absence of metaphyseal changes may indicate sterilization of cartilage cells and may be predictive of significant limb shortening.

  13. Implications of the Bystander and Abscopal Effects of Radiation Therapy.

    Science.gov (United States)

    Verma, Vivek; Lin, Steven H

    2016-10-01

    Siva and colleagues have demonstrated that localized thoracic radiation resulted in DNA damage at out-of-field sites. Although these interesting findings require validation, we discuss the important clinical implications of these data, especially in the era of immune therapies. Clin Cancer Res; 22(19); 4763-5. ©2016 AACRSee related article by Siva et al., p. 4817. ©2016 American Association for Cancer Research.

  14. Sick sinus syndrome as a complication of mediastinal radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Pohjola-Sintonen, S.; Toetterman, K.J.K.; Kupari, M. (Helsinki Univ. Central Hospital (Finland))

    1990-06-01

    A 33-year-old man who had received mediastinal radiation therapy for Hodgkin's disease 12 years earlier developed a symptomatic sick sinus syndrome requiring the implantation of a permanent pacemaker. The sick sinus syndrome and a finding of an occult constrictive pericarditis were considered to be due to the previous mediastinal irradiation. A ventricular pacemaker was chosen because mediastinal radiotherapy also increases the risk of developing atrioventricular conduction defects.

  15. Definitive radiation therapy for infiltrative thyroid carcinoma in dogs.

    Science.gov (United States)

    Pack, L; Roberts, R E; Dawson, S D; Dookwah, H D

    2001-01-01

    The medical records of eight dogs with histopathologically confirmed infiltrative thyroid carcinoma treated with external beam radiation were reviewed and a retrospective analysis of survival and local tumor control were performed. The dogs received a definitive radiotherapy protocol of 46.8-48 Gray. All dogs had a reduction in tumor size to a clinically undetectable level on follow up examinations. Kaplan-Meier analysis indicated a median survival time of 24.5 months. Pulmonary metastasis was detected in three dogs and one of these dogs had concurrent bone metastasis. One dog had bone metastasis alone. Two dogs were alive at the censor. This study suggests that fractionated, definitive radiation therapy using multiple, moderate doses of radiation is an effective treatment for local control of invasive thyroid carcinoma in dogs.

  16. Sparing of tissue by using micro-slit-beam radiation therapy reduces neurotoxicity compared with broad-beam radiation therapy.

    Science.gov (United States)

    Mukumoto, Naritoshi; Nakayama, Masao; Akasaka, Hiroaki; Shimizu, Yasuyuki; Osuga, Saki; Miyawaki, Daisuke; Yoshida, Kenji; Ejima, Yasuo; Miura, Yasushi; Umetani, Keiji; Kondoh, Takeshi; Sasaki, Ryohei

    2017-01-01

    Micro-slit-beam radiation therapy (MRT) using synchrotron-generated X-ray beams allows for extremely high-dose irradiation. However, the toxicity of MRT in central nervous system (CNS) use is still unknown. To gather baseline toxicological data, we evaluated mortality in normal mice following CNS-targeted MRT. Male C57BL/6 J mice were head-fixed in a stereotaxic frame. Synchrotron X-ray-beam radiation was provided by the SPring-8 BL28B2 beam-line. For MRT, radiation was delivered to groups of mice in a 10 × 12 mm unidirectional array consisting of 25-μm-wide beams spaced 100, 200 or 300 μm apart; another group of mice received the equivalent broad-beam radiation therapy (BRT) for comparison. Peak and valley dose rates of the MRT were 120 and 0.7 Gy/s, respectively. Delivered doses were 96-960 Gy for MRT, and 24-120 Gy for BRT. Mortality was monitored for 90 days post-irradiation. Brain tissue was stained using hematoxylin and eosin to evaluate neural structure. Demyelination was evaluated by Klüver-Barrera staining. The LD50 and LD100 when using MRT were 600 Gy and 720 Gy, respectively, and when using BRT they were 80 Gy and 96 Gy, respectively. In MRT, mortality decreased as the center-to-center beam spacing increased from 100 μm to 300 μm. Cortical architecture was well preserved in MRT, whereas BRT induced various degrees of cerebral hemorrhage and demyelination. MRT was able to deliver extremely high doses of radiation, while still minimizing neuronal death. The valley doses, influenced by beam spacing and irradiated dose, could represent important survival factors for MRT. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  17. Hyperbaric oxygen therapy for refractory radiation-induced hemorrhagic cystitis.

    Science.gov (United States)

    Ribeiro de Oliveira, Tiago M; Carmelo Romão, António J; Gamito Guerreiro, Francisco M; Matos Lopes, Tomé M

    2015-10-01

    To analyze the efficacy of hyperbaric oxygen for the treatment of radiation-induced hemorrhagic cystitis and to identify factors associated with successful treatment. Clinical records from 176 patients with refractory radiation-induced hemorrhagic cystitis treated at the Portuguese Navy Center for Underwater and Hyperbaric Medicine, during a 15-year period, were retrospectively analyzed. Evolution of macroscopic hematuria was used to analyze treatment efficacy and correlated with other external variables. From a total of 176 treated patients, 23.9% evidenced other radiation-induced soft tissue lesions. After an average on 37 sessions, 89.8% of patients showed resolution of hematuria, with only 1.7% of adverse events. In our sample, hematuria resolution after treatment with hyperbaric oxygen was statistically associated to the need for transfusion therapy (P = 0.026) and the number of sessions of hyperbaric oxygen (P = 0.042). No relationship was found with the remaining variables. Refractory radiation-induced hemorrhagic cystitis can be successfully and safely treated with hyperbaric oxygen. Treatment effectiveness seems to be correlated with the need for transfusion therapy and the number of sessions performed. © 2015 The Japanese Urological Association.

  18. Brachytherapy with an improved MammoSite Radiation Therapy System

    Science.gov (United States)

    Karthik, Nanda; Keppel, Cynthia; Nazaryan, Vahagn

    2007-03-01

    Accelerated partial breast irradiation treatment utilizing the MammoSite Radiation Therapy System (MRTS) is becoming increasingly popular. Clinical studies show excellent results for disease control and localization, as well as for cosmesis. Several Phase I, II, and III clinical trials have found significant association between skin spacing and cosmetic results after treatment with MRTS. As a result, patients with skin spacing less then 7 mm are not recommended to undergo this treatment. We have developed a practical innovation to the MammoSite brachytherapy methodology that is directed to overcome the skin spacing problem. The idea is to partially shield the radiation dose to the skin where the skin spacing is less then 7 mm, thereby protecting the skin from radiation damage. Our innovation to the MRTS will allow better cosmetic outcome in breast conserving therapy (BCT), and will furthermore allow more women to take advantage of BCT. Reduction in skin radiation exposure is particularly important for patients also undergoing adjuvant chemotherapy. We will present the method and preliminary laboratory and Monte Carlo simulation results.

  19. The Role of Postoperative Pelvic Radiation Therapy in Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Yong Chan; Kim, Jae Sung; Yun, Hyong Geun; Ha, Sung Whan; Park, Charn Il [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1991-06-15

    To evaluate the role of postoperative pelvic radiation therapy in rectal cancer, a retrospective analysis was done on 189 patients with modified Astler-Coller stages B2+3, C1, and C2+3 who were treated from February 1979 to June 1986. Forty-seven patients were staged as B2+3, 17 as C1, and 125 as C2+3. As a curative resection, 41 received low anterior resection, 143 received abdomino-perineal resection, and five received pelvic exenteration. The survival and disease-free survival rates of the total patients at five year were 45.3% and 44.1%, respectively. The stage was an important prognostic factor for survival and disease-free survival: the survival rates at five year were 55.7% in B2+3, 65.7% in C1, and 36.4% in C2+3, respectively (p<0.01). The liver was the most frequently involved organ of recurrence followed by the lung and the perineum. The patients who received low anterior resection achieved better disease-free survival but were more prone to late radiation bowel morbidities than those who received abdominoperineal resection. Postoperative pelvic radiation therapy proved to be effective in locoregional disease control but did not prevent the appearance of distant metastasis, which was of major concern in advanced stages. Patterns of treatment failure, and factors relating to radiation morbidity are discussed, and therapeutic options for better results are proposed.

  20. Prone Breast Intensity Modulated Radiation Therapy: 5-Year Results

    Energy Technology Data Exchange (ETDEWEB)

    Osa, Etin-Osa O.; DeWyngaert, Keith [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States); Roses, Daniel [Department of Surgery, New York University School of Medicine, New York, New York (United States); Speyer, James [Department of Medical Oncology, New York University School of Medicine, New York, New York (United States); Guth, Amber; Axelrod, Deborah [Department of Surgery, New York University School of Medicine, New York, New York (United States); Fenton Kerimian, Maria [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States); Goldberg, Judith D. [Department of Population Health, New York University School of Medicine, New York, New York (United States); Formenti, Silvia C., E-mail: Silvia.formenti@nyumc.org [Department of Radiation Oncology, New York University School of Medicine, New York, New York (United States)

    2014-07-15

    Purpose: To report the 5-year results of a technique of prone breast radiation therapy delivered by a regimen of accelerated intensity modulated radiation therapy with a concurrent boost to the tumor bed. Methods and Materials: Between 2003 and 2006, 404 patients with stage I-II breast cancer were prospectively enrolled into 2 consecutive protocols, institutional trials 03-30 and 05-181, that used the same regimen of 40.5 Gy/15 fractions delivered to the index breast over 3 weeks, with a concomitant daily boost to the tumor bed of 0.5 Gy (total dose 48 Gy). All patients were treated after segmental mastectomy and had negative margins and nodal assessment. Patients were set up prone: only if lung or heart volumes were in the field was a supine setup attempted and chosen if found to better spare these organs. Results: Ninety-two percent of patients were treated prone, 8% supine. Seventy-two percent had stage I, 28% stage II invasive breast cancer. In-field lung volume ranged from 0 to 228.27 cm{sup 3}, mean 19.65 cm{sup 3}. In-field heart volume for left breast cancer patients ranged from 0 to 21.24 cm{sup 3}, mean 1.59 cm{sup 3}. There was no heart in the field for right breast cancer patients. At a median follow-up of 5 years, the 5-year cumulative incidence of isolated ipsilateral breast tumor recurrence was 0.82% (95% confidence interval [CI] 0.65%-1.04%). The 5-year cumulative incidence of regional recurrence was 0.53% (95% CI 0.41%-0.69%), and the 5-year overall cumulative death rate was 1.28% (95% CI 0.48%-3.38%). Eighty-two percent (95% CI 77%-85%) of patients judged their final cosmetic result as excellent/good. Conclusions: Prone accelerated intensity modulated radiation therapy with a concomitant boost results in excellent local control and optimal sparing of heart and lung, with good cosmesis. Radiation Therapy Oncology Group protocol 1005, a phase 3, multi-institutional, randomized trial is ongoing and is evaluating the equivalence of a similar dose and

  1. Breast Cancer Biology: Clinical Implications for Breast Radiation Therapy.

    Science.gov (United States)

    Horton, Janet K; Jagsi, Reshma; Woodward, Wendy A; Ho, Alice

    2018-01-01

    Historically, prognosis and treatment decision making for breast cancer patients have been dictated by the anatomic extent of tumor spread. However, in recent years, "breast cancer" has proven to be a collection of unique phenotypes with distinct prognoses, patterns of failure, and treatment responses. Recent advances in biologically based assays and targeted therapies designed to exploit these unique phenotypes have profoundly altered systemic therapy practice patterns and treatment outcomes. Data associating locoregional outcomes with tumor biology are emerging. However, the likelihood of obtaining level I evidence for fundamental radiation therapy questions within each of the specific subtypes in the immediate future is low. As such, this review aims to summarize the existing data and provide practical context for the incorporation of breast tumor biology into clinical practice. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Imaging Changes in Pediatric Intracranial Ependymoma Patients Treated With Proton Beam Radiation Therapy Compared to Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Gunther, Jillian R. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Sato, Mariko; Chintagumpala, Murali [Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Texas Children' s Cancer Center, Houston, Texas (United States); Ketonen, Leena [Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Jones, Jeremy Y. [Department of Pediatric Radiology, Texas Children' s Hospital, Houston, Texas (United States); Allen, Pamela K. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Paulino, Arnold C. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Texas Children' s Cancer Center, Houston, Texas (United States); Okcu, M. Fatih; Su, Jack M. [Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Texas Children' s Cancer Center, Houston, Texas (United States); Weinberg, Jeffrey [Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Boehling, Nicholas S. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Khatua, Soumen [Department of Pediatrics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Adesina, Adekunle [Department of Pathology, Baylor College of Medicine, Texas Children' s Hospital, Houston, Texas (United States); Dauser, Robert; Whitehead, William E. [Department of Neurosurgery, Texas Children' s Hospital, Houston, Texas (United States); Mahajan, Anita, E-mail: amahajan@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2015-09-01

    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.

  3. Analysis of radiation pneumonitis outside the radiation field in breast conserving therapy for early breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ogo, Etsuyo; Fujimoto, Kiminori; Hayabuchi, Naofumi [Kurume Univ., Fukuoka (Japan). School of Medicine] (and others)

    2002-02-01

    In a retrospective study of radiation-induced pulmonary changes for patients with breast conserving therapy for early breast cancer, we sent questionnaires to the main hospitals in Japan. In this study, we analyzed pulmonary changes after tangential whole-breast irradiation. The purpose of this study was to determine the incidence and risk factors for radiation pneumonitis outside the radiation field. The questionnaires included patients data, therapy data, and lung injury information between August 1999 and May 2000. On the first questionnaires, answer letters were received from 107 institutions out of 158 (67.7%). On the second questionnaires, response rate (hospitals which had radiation pneumonitis outside the radiation field) was 21.7% (23/106). We could find no risk factors of this type of pneumonitis. We suggested that lung irradiation might trigger this type of pneumonitis which is clinically similar to BOOP (bronchiolitis obliterans organizing pneumonia). It developed in 1.5-2.1% among the patients with breast conserving surgery and tangential whole-breast irradiation. And it is likely appeared within 6 months after radiotherapy. (author)

  4. Evaluation of patients' engagement in radiation therapy safety.

    Science.gov (United States)

    Pernet, A; Mollo, V; Bibault, J-E; Giraud, P

    2016-12-01

    Treatment safety has become a priority in health policies after several incidents occurred around the world in radiation oncology departments. The aim of this study was to analyse the patients' contribution in that field and to understand which actions empower the patient in that regard. Several methods were used in a general hospital and in a comprehensive cancer centre to analyse the activities of the radiation therapists and the patients and the interactions between them: treatment session observations, semidirective interviews with radiation therapists and patients, self and alloconfrontation with radiation therapists and explanatory interviews with patients. Cooperation of the patients in treatment safety acts as an additional step that contributes to safer treatments. Radiation therapy sessions are a creative opportunity for the patient to observe, learn and analyse what is happening. Changes between treatment sessions are a source of anxiety for the patients. This study highlights the factors that favour the patients' participation. A trusting relationship and support from the health professionals can be leveraged in that manner. There is a common will shared between the patients and the health professionals towards better treatment safety. The cooperation is still not well-known and underused. This empowerment of the patient cannot be mandatory but should be promoted and developed. Copyright © 2016. Published by Elsevier SAS.

  5. Current status of radiation therapy. Evidence-based medicine (EBM) of radiation therapy. Non-Hodgkin's lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Oguchi, Masahiko; Gomi, Koutaro [Japanese Foundation for Cancer Research, Tokyo (Japan). Hospital; Shikama, Naoto [Shinshu Univ., Matsumoto, Nagano (Japan). Hospital

    2002-04-01

    Non-Hodgkin's lymphomas (NHLs) are a heterogeneous group of lympho-proliferative disorders, mainly originating in lymphoid tissues and other extranodal organs, with different patterns of behavior. Prognosis depends on the histo-pathologic type, prognostic factors, and treatment. According to the WHO classification (2001), the NHLs are divided into two prognostic groups: the indolent lymphomas (follicular lymphoma, marginal zone B-cell lymphoma, etc.) and the aggressive lymphomas (diffuse large B-cell lymphoma, peripheral T-cell lymphoma, etc.). Indolent NHLs have a good prognosis, with median survival as long as 10 years, and early stage (I and II) indolent NHLs can be treated with radiation therapy alone, with 70% to 90% 5-year overall survival rates. The aggressive NHLs have shorter natural histories, but the number of patients cured with intensive chemotherapy currently is increasing. In general, overall survival at 5 years is approximately 50% to 60%. Patients with stage I and contiguous stage II aggressive NHLs enjoy excellent survival rates when treated with a combined modality including chemotherapy (CHOP) and radiation therapy. The radiation dose for NHLs varies from 25 to 50 Gy and is dependent on pathologic type and the organs at risk. Radiation fields are basically limited to involved regions or extended to immediately adjacent sites. Localized presentations of extranodal NHLs can be treated with involved-field techniques with significant success. However, the long-term adverse reactions must be considered carefully. (author)

  6. Radiation-induced myocardial perfusion abnormalities in breast cancer patients following external beam radiation therapy

    Directory of Open Access Journals (Sweden)

    Mohammad Eftekhari

    2015-01-01

    Full Text Available Objective(s: 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. Methods: 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. Results: 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. Conclusion: The risk of radiation induced myocardial

  7. Anonymization of DICOM electronic medical records for radiation therapy.

    Science.gov (United States)

    Newhauser, Wayne; Jones, Timothy; Swerdloff, Stuart; Newhauser, Warren; Cilia, Mark; Carver, Robert; Halloran, Andy; Zhang, Rui

    2014-10-01

    Electronic medical records (EMR) and treatment plans are used in research on patient outcomes and radiation effects. In many situations researchers must remove protected health information (PHI) from EMRs. The literature contains several studies describing the anonymization of generic Digital Imaging and Communication in Medicine (DICOM) files and DICOM image sets but no publications were found that discuss the anonymization of DICOM radiation therapy plans, a key component of an EMR in a cancer clinic. In addition to this we were unable to find a commercial software tool that met the minimum requirements for anonymization and preservation of data integrity for radiation therapy research. The purpose of this study was to develop a prototype software code to meet the requirements for the anonymization of radiation therapy treatment plans and to develop a way to validate that code and demonstrate that it properly anonymized treatment plans and preserved data integrity. We extended an open-source code to process all relevant PHI and to allow for the automatic anonymization of multiple EMRs. The prototype code successfully anonymized multiple treatment plans in less than 1min/patient. We also tested commercial optical character recognition (OCR) algorithms for the detection of burned-in text on the images, but they were unable to reliably recognize text. In addition, we developed and tested an image filtering algorithm that allowed us to isolate and redact alpha-numeric text from a test radiograph. Validation tests verified that PHI was anonymized and data integrity, such as the relationship between DICOM unique identifiers (UID) was preserved. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. A point kernel algorithm for microbeam radiation therapy

    Science.gov (United States)

    Debus, Charlotte; Oelfke, Uwe; Bartzsch, Stefan

    2017-11-01

    Microbeam radiation therapy (MRT) is a treatment approach in radiation therapy where the treatment field is spatially fractionated into arrays of a few tens of micrometre wide planar beams of unusually high peak doses separated by low dose regions of several hundred micrometre width. In preclinical studies, this treatment approach has proven to spare normal tissue more effectively than conventional radiation therapy, while being equally efficient in tumour control. So far dose calculations in MRT, a prerequisite for future clinical applications are based on Monte Carlo simulations. However, they are computationally expensive, since scoring volumes have to be small. In this article a kernel based dose calculation algorithm is presented that splits the calculation into photon and electron mediated energy transport, and performs the calculation of peak and valley doses in typical MRT treatment fields within a few minutes. Kernels are analytically calculated depending on the energy spectrum and material composition. In various homogeneous materials peak, valley doses and microbeam profiles are calculated and compared to Monte Carlo simulations. For a microbeam exposure of an anthropomorphic head phantom calculated dose values are compared to measurements and Monte Carlo calculations. Except for regions close to material interfaces calculated peak dose values match Monte Carlo results within 4% and valley dose values within 8% deviation. No significant differences are observed between profiles calculated by the kernel algorithm and Monte Carlo simulations. Measurements in the head phantom agree within 4% in the peak and within 10% in the valley region. The presented algorithm is attached to the treatment planning platform VIRTUOS. It was and is used for dose calculations in preclinical and pet-clinical trials at the biomedical beamline ID17 of the European synchrotron radiation facility in Grenoble, France.

  9. Survival times for canine intranasal sarcomas treated with radiation therapy: 86 cases (1996-2011).

    Science.gov (United States)

    Sones, Evan; Smith, Annette; Schleis, Stephanie; Brawner, William; Almond, Gregory; Taylor, Kathryn; Haney, Siobhan; Wypij, Jackie; Keyerleber, Michele; Arthur, Jennifer; Hamilton, Terrance; Lawrence, Jessica; Gieger, Tracy; Sellon, Rance; Wright, Zack

    2013-01-01

    Sarcomas comprise approximately one-third of canine intranasal tumors, however few veterinary studies have described survival times of dogs with histologic subtypes of sarcomas separately from other intranasal tumors. One objective of this study was to describe median survival times for dogs treated with radiation therapy for intranasal sarcomas. A second objective was to compare survival times for dogs treated with three radiation therapy protocols: daily-fractionated radiation therapy; Monday, Wednesday, and Friday fractionated radiation therapy; and palliative radiation therapy. Medical records were retrospectively reviewed for dogs that had been treated with radiation therapy for confirmed intranasal sarcoma. A total of 86 dogs met inclusion criteria. Overall median survival time for included dogs was 444 days. Median survival time for dogs with chondrosarcoma (n = 42) was 463 days, fibrosarcoma (n = 12) 379 days, osteosarcoma (n = 6) 624 days, and undifferentiated sarcoma (n = 22) 344 days. Dogs treated with daily-fractionated radiation therapy protocols; Monday, Wednesday and Friday fractionated radiation therapy protocols; and palliative radiation therapy protocols had median survival times of 641, 347, and 305 days, respectively. A significant difference in survival time was found for dogs receiving curative intent radiation therapy vs. palliative radiation therapy (P = 0.032). A significant difference in survival time was also found for dogs receiving daily-fractionated radiation therapy vs. Monday, Wednesday and Friday fractionated radiation therapy (P = 0.0134). Findings from this study support the use of curative intent radiation therapy for dogs with intranasal sarcoma. Future prospective, randomized trials are needed for confirmation of treatment benefits. © 2012 Veterinary Radiology & Ultrasound.

  10. Accuracy of marketing claims by providers of stereotactic radiation therapy.

    Science.gov (United States)

    Narang, Amol K; Lam, Edwin; Makary, Martin A; Deweese, Theodore L; Pawlik, Timothy M; Pronovost, Peter J; Herman, Joseph M

    2013-01-01

    Direct-to-consumer advertising by industry has been criticized for encouraging overuse of unproven therapies, but advertising by health care providers has not been as carefully scrutinized. Stereotactic radiation therapy is an emerging technology that has sparked controversy regarding the marketing campaigns of some manufacturers. Given that this technology is also being heavily advertised on the Web sites of health care providers, the accuracy of providers' marketing claims should be rigorously evaluated. We reviewed the Web sites of all U.S. hospitals and private practices that provide stereotactic radiation using two leading brands of stereotactic radiosurgery technology. Centers were identified by using data from the manufacturers. Centers without Web sites were excluded. The final study population consisted of 212 centers with online advertisements for stereotactic radiation. Web sites were evaluated for advertisements that were inconsistent with advertising guidelines provided by the American Medical Association. Most centers (76%) had individual pages dedicated to the marketing of their brand of stereotactic technology that frequently contained manufacturer-authored images (50%) or text (55%). Advertising for the treatment of tumors that have not been endorsed by professional societies was present on 66% of Web sites. Centers commonly claimed improved survival (22%), disease control (20%), quality of life (17%), and toxicity (43%) with stereotactic radiation. Although 40% of Web sites championed the center's regional expertise in delivering stereotactic treatments, only 15% of Web sites provided data to support their claims. Provider advertisements for stereotactic radiation were prominent and aggressive. Further investigation of provider advertising, its effects on quality of care, and potential oversight mechanisms is needed.

  11. Accuracy of Marketing Claims by Providers of Stereotactic Radiation Therapy

    Science.gov (United States)

    Narang, Amol K.; Lam, Edwin; Makary, Martin A.; DeWeese, Theodore L.; Pawlik, Timothy M.; Pronovost, Peter J.; Herman, Joseph M.

    2013-01-01

    Purpose: Direct-to-consumer advertising by industry has been criticized for encouraging overuse of unproven therapies, but advertising by health care providers has not been as carefully scrutinized. Stereotactic radiation therapy is an emerging technology that has sparked controversy regarding the marketing campaigns of some manufacturers. Given that this technology is also being heavily advertised on the Web sites of health care providers, the accuracy of providers' marketing claims should be rigorously evaluated. Methods: We reviewed the Web sites of all US hospitals and private practices that provide stereotactic radiation using two leading brands of stereotactic radiosurgery technology. Centers were identified by using data from the manufacturers. Centers without Web sites were excluded. The final study population consisted of 212 centers with online advertisements for stereotactic radiation. Web sites were evaluated for advertisements that were inconsistent with advertising guidelines provided by the American Medical Association. Results: Most centers (76%) had individual pages dedicated to the marketing of their brand of stereotactic technology that frequently contained manufacturer-authored images (50%) or text (55%). Advertising for the treatment of tumors that have not been endorsed by professional societies was present on 66% of Web sites. Centers commonly claimed improved survival (22%), disease control (20%), quality of life (17%), and toxicity (43%) with stereotactic radiation. Although 40% of Web sites championed the center's regional expertise in delivering stereotactic treatments, only 15% of Web sites provided data to support their claims. Conclusion: Provider advertisements for stereotactic radiation were prominent and aggressive. Further investigation of provider advertising, its effects on quality of care, and potential oversight mechanisms is needed. PMID:23633973

  12. Implementation of MRI gel dosimetry in radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Baeck, S.Aa.J

    1998-12-01

    Gel dosimetry was used together with magnetic resonance imaging (MRI) to measure three-dimensional absorbed dose distributions in radiation therapy. Two different dosimeters were studied: ferrous- and monomer gel, based on the principles of radiation-induced oxidation and polymerisation, respectively. Single clinical electron and photon beams were evaluated and gel dose distributions were mainly within 2% of conventional detector results. The ferrous-gel was also used for clinical proton beams. A decrease in signal per absorbed dose was found close to the end of the range of the protons (15-20%). This effect was explained as a linear energy transfer dependence, further supported with Monte Carlo simulations. A method for analysing and comparing data from treatment planning system (TPS) and gel measurements was developed. The method enables a new pixel by pixel evaluation, isodose comparison and dose volume histogram verification. Two standard clinical radiation therapy procedures were examined using the developed TPS verification method. The treatment regimes included several beams of different radiation qualities. The TPS calculated data were in very good agreement with the dose distribution measured by the ferrous-gel. However, in a beam abutment region, larger dose difference was found. Beam adjustment errors and a minor TPS underestimation of the lateral scatter contribution outside the primary electron beam may explain the discrepancy. The overall uncertainty in the ferrous-gel dose determination was considerably reduced using an optimised MRI acquisition protocol and a new MRI scanner. The relative dose uncertainty was found to be better than 3.3% for all dose levels (95% confidence level). Using the method developed for comparing measured gel data with calculated treatment plans, the gel dosimetry method was proven to be a useful tool for radiation treatment planning verification 103 refs, 20 figs, 6 tabs

  13. Towards magnetic resonance imaging guided radiation therapy (MRIgRT)

    Science.gov (United States)

    Stanescu, Teodor Marius

    The goal of this work is to address key aspects of the magnetic resonance imaging guided radiation therapy (MRIgRT) process of cancer sites. MRIgRT is implemented by using a system comprised of a magnetic resonance imaging (MRI) scanner coupled with a radiation source, in our case a radiotherapy accelerator (Linac). The potential benefits of MRIgRT are the real-time tracking of the tumor and neighbouring healthy anatomy during treatment irradiation leading to on-line treatment plan optimization. Ultimately, this results in an increased accuracy and efficiency of the overall treatment process. A large research effort is conducted at Cross Cancer Institute to develop a hybrid MRI-Linac system consisting of a bi-planar 0.2 T permanent magnet coupled with a 6 MV Linac. The present work is part of this project and aims to address the following key components: (a) magnetic shielding and dosimetric effects of the MRI-Linac system, (b) measure and correction of scanner-related MR image distortions, and (c) MRI-based treatment planning procedure for intracranial lesions. The first two components are essential for the optimal construction and operation of the MRI-Linac system while the third one represents a direct application of the system. The linac passive shielding was achieved by (a) adding two 10 cm thick steel (1020) plates placed at a distance of 10 cm from the structure on opposite sides of the magnet; and (b) a box lined with a 1 mm MuMetal(TM) wall surrounding the Linac. For our proposed MRI-Linac configuration (i.e. 0.2 T field and rotating bi-planar geometry) the maximum dose difference from zero magnetic field case was found to be within 6% and 12% in a water and water-lung-water phantom, respectively. We developed an image system distortion correction method for MRI that relies on adaptive thresholding and an iterative algorithm to determine the 3D distortion field. Applying this technique the residual image distortions were reduced to within the voxel

  14. Online adaptive assistance control in robot-based neurorehabilitation therapy.

    Science.gov (United States)

    Stroppa, Fabio; Marcheschi, Simone; Mastronicola, Nicola; Loconsole, Claudio; Frisoli, Antonio

    2017-07-01

    Repetitive and task specific robot-based rehabilitation has been proved to be effective for motor recovery over time. During a therapy, the task should improve subject's impaired movements, but also enhance their efforts for a more effective recovery. This requires an accurate tuning of the task difficulty, which should be tailored directly to the patient. In this work, we propose a system for real-time assistance adaptation based on online performance evaluation for post-stroke subjects. In particular, the aim of the system is to implement the "assist-as-needed" paradigm based on actual patients' motor skills during a therapy session with an active upper-limb robotic exoskeleton. The strength of the work is to propose a real-time algorithm for the assistance tuning based on an "assistance-performance" relationship. Such a relationship is based on experimental measurements, and allows the algorithm to compute a straightforward calculation of the assistance required. Finally, an assessment phase will show how the system provides assistance based on the difficulties experienced from the subjects, also facilitating their adaptation during the task.

  15. The Adaptive Radiation of Cichlid Fish in Lake Tanganyika: A Morphological Perspective

    Directory of Open Access Journals (Sweden)

    Tetsumi Takahashi

    2011-01-01

    Full Text Available Lake Tanganyika is the oldest of the Great Ancient Lakes in the East Africa. This lake harbours about 250 species of cichlid fish, which are highly diverse in terms of morphology, behaviour, and ecology. Lake Tanganyika's cichlid diversity has evolved through explosive speciation and is treated as a textbook example of adaptive radiation, the rapid differentiation of a single ancestor into an array of species that differ in traits used to exploit their environments and resources. To elucidate the processes and mechanisms underlying the rapid speciation and adaptive radiation of Lake Tanganyika's cichlid species assemblage it is important to integrate evidence from several lines of research. Great efforts have been, are, and certainly will be taken to solve the mystery of how so many cichlid species evolved in so little time. In the present review, we summarize morphological studies that relate to the adaptive radiation of Lake Tanganyika's cichlids and highlight their importance for understanding the process of adaptive radiation.

  16. Adjuvant postoperative radiation therapy for carcinoma of the uterine cervix

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Ja; Moon, Hye Seong; Kim, Seung Cheol; Kim, Chong Il; Ahn, Jung Ja [College of Medicine, Ewha Womans Univ., Seoul (Korea, Republic of)

    2003-09-01

    This study was undertaken to evaluate the efficacy of postoperative radiotherapy, and to investigate the prognostic factors for FIGO stages IB-IIB cervical cancer patients who were treated with simple hysterectomy, or who had high-risk factors following radical hysterectomy and pelvic lymph node dissection. Between March 1986 and December 1998, 58 patients, with FIGO stages IB-IIB cervical cancer were included in this study, The indications for postoperative radiation therapy were based on the pathological findings, including lymph node metastasis, positive surgical margin, parametrial extension, Iymphovascular invasion, invasion of more than half the cervical stroma, uterine extension and the incidental finding of cervix cancer following simple hysterectomy. All patients received external pelvic radiotherapy, and 5 patients, received an additional intracavitary radiation therapy. The radiation dose from the external beam to the whole pelvis was 45 - 50 Gy. Vagina cuff irradiation was performed, after completion of the external beam irradiation, al a low-dose rate of CS-137, with the total dose of 4488-4932 chy (median: 4500 chy) at 5 mm depth from the vagina surface. The median follow-up period was 44 months (15-108 months), The 5-yr actuarial local control rate, distant free survival and disease-free survival rate were 98%, 95% and 94%, respectively. A univariate analysis of the clinical and pathological parameters revealed that the clinical stage (p=0.0145), status of vaginal resection margin (p=0.0002) and parametrial extension (p=0.0001) affected the disease-free survival. From a multivariate analysis, only a parametrial extension independently influenced the disease-free survival. Five patients (9%) experienced Grade 2 late treatment-related complications, such as radiation proctitis (1 patient), cystitis (3 patients) and lymphedema of the leg (1 patient). No patient had grade 3 or 4 complications. Our results indicate that postoperative radiation therapy can

  17. Failure of odontogenesis after chemo-radiation therapy for rhabdomyosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sun Young; Hong, Sung Woo; Koh, Kwang Joon [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Chonbuk National University, Chonju (Korea, Republic of)

    1998-02-15

    This report details a case of 8-year-old girl showing failure of odontogenesis after chemo-radiation therapy for rhabdomysarcoma at the age of 4. The observed results were as follows: 1. Past history revealed that she had received for a total radiation dose od 4430 cGy, 29 fractions in 6 weeks and chemotherapy with vincristine, actinomycin D and cytoxan, followed as maintenance phase for 2 years. 2. The patient was symptom-free and appointed for the treatment of multiple dental caries. 3. Oral examination showed hypoplastic enamel on whole erupted permanent teeth and showed retarded eruption. 4. Conventional radiograms showed failure of root development including abrupt cessation of root formation and root agenesis, and microdobtia, missing teeth, irregular enamel, dislocation of the impacted teeth. Additional finding showed good healing bone pattern on the left mandibular ramus and angle area. 5. Cehalometric analysis revealed failure of bite raising due to incomplete eruption of all the first molars and made it possible to suspect entrapped mandibular growth and then Class II tendency growth. 6. There was correlation between the time of chemo-radiation therapy and the damage of the teeth.

  18. Combined preoperative therapy for oral cancer with nedaplatin and radiation

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Masatoshi; Shibata, Akihiko; Hayashi, Munehiro [Nippon Dental Univ., Tokyo (Japan). Hospital] (and others)

    2002-03-01

    We performed preoperative combined therapy using nedaplatin (CDGP) and radiation in 12 patients with squamous cell carcinoma originating from the oral cavity and maxillary sinus, and examined for any adverse events that may have occurred during this therapeutic regimen. Regarding the irradiation, external irradiation utilizing a 6 MV linac (linear accelerator) at a dose of 2.0 Gy/day was performed 5 times a week, with the target total radiation dose set at 40 Gy. In addition, CDGP was intravenously administered 30 minutes before irradiation at a dose of 5 mg/m{sup 2}/day. Mucositis was observed in all 12 subjects, however, the severity was observed to be grade 1-2 with no major differences in comparison to the patients given standard radiation monotherapy. Two subjects developed grade 3 leucopenia and were thus given granulocyte colony stimulating factor (G-CSF). In addition, grade 2 and grade 3 thrombocytopenia were both observed in one subject each. The subject with grade 3 thrombocytopenia required a platelet transfusion during surgery. No marked changes in serum creatinine levels were noted. These findings are therefore considered to provide evidence supporting the safety of this combination therapy. (author)

  19. Radiation Physics and Chemistry in Heavy-ion Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Kimura, M.

    2007-12-01

    Full Text Available Heavy ions, such as carbon and oxygen ions, are classified as high-LET radiations, and produce a characteristic dose-depth distribution different from that of low-LET radiations such as γ-rays, xrays and electrons. Heavy ions lose less energy at the entrance to an irradiated biological system up to some depth than the low-LET radiations, while they deposit a large amount of dose within a very narrow range at a certain depth, producing the characteristic sharp peak called the Bragg peak. Therefore, by controlling the Bragg peak, it becomes possible to irradiate only the tumor region in a pin-point manner, while avoiding irradiation of the normal tissue, thus making heavyion therapy ideal for deep-seated tumor treatment. Clinical results on more than 2400 patients are very encouraging. However, very little is known about what is going on in terms of physics and chemistry inside the Bragg peak. In this paper the current status of our understanding of heavy-ion interactions and remaining problems of physics and chemistry for the heavy-ion treatment are explored, particularly in the Bragg peak region. Specially, the survey of the basic physical quantity, the mean energy required to form an ion pair (Wvalue for heavy ions of interest for radiotherapy is presented. Finally, the current clinical status of heavy-ion therapy is presented.

  20. The role of medical physics in prostate cancer radiation therapy.

    Science.gov (United States)

    Fiorino, Claudio; Seuntjens, Jan

    2016-03-01

    Medical physics, both as a scientific discipline and clinical service, hugely contributed and still contributes to the advances in the radiotherapy of prostate cancer. The traditional translational role in developing and safely implementing new technology and methods for better optimizing, delivering and monitoring the treatment is rapidly expanding to include new fields such as quantitative morphological and functional imaging and the possibility of individually predicting outcome and toxicity. The pivotal position of medical physicists in treatment personalization probably represents the main challenge of current and next years and needs a gradual change of vision and training, without losing the traditional and fundamental role of physicists to guarantee a high quality of the treatment. The current focus issue is intended to cover traditional and new fields of investigation in prostate cancer radiation therapy with the aim to provide up-to-date reference material to medical physicists daily working to cure prostate cancer patients. The papers presented in this focus issue touch upon present and upcoming challenges that need to be met in order to further advance prostate cancer radiation therapy. We suggest that there is a smart future for medical physicists willing to perform research and innovate, while they continue to provide high-quality clinical service. However, physicists are increasingly expected to actively integrate their implicitly translational, flexible and high-level skills within multi-disciplinary teams including many clinical figures (first of all radiation oncologists) as well as scientists from other disciplines. Copyright © 2016. Published by Elsevier Ltd.

  1. Phantom dosimetry at 15 MV conformal radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Larissa; Campos, Tarcisio P.R., E-mail: larissathompson@hotmail.com, E-mail: tprcampos@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Dias, Humberto G., E-mail: fisicamedica.hl@mariopenna.org.br [Luxemburgo Hospital, Mario Penna Institute, Belo Horizonte, MG (Brazil)

    2015-07-01

    The main goal of this work was to evaluate the spatial dose distribution into a tumor simulator inside a head phantom exposed to a 15MV 3D conformal radiation therapy in order to validate internal doses. A head and neck phantom developed by the Ionizing Radiation Research Group (NRI) was used on the experiments. Therapy Radiation planning (TPS) was performed based on those CT images, satisfying a 200 cGy prescribed dose split in three irradiation fields. The TPS assumed 97% of prescribed dose cover the prescribed treatment volume (PTV). Radiochromic films in a solid water phantom provided dose response as a function of optical density. Spatial dosimetric distribution was generated by radiochromic film samples inserted into tumor simulator and brain. The spatial dose profiles held 70 to 120% of the prescribed dose. In spite of the stratified profile, as opposed to the smooth dose profile from TPS, the tumor internal doses were within a 5% deviation from 214.4 cGy evaluated by TPS. 83.2% of the points with a gamma value of less than 1 (3%/3mm) for TPS and experimental values, respectively. At the tumor, a few dark spots in the film caused the appearance of outlier points in 13-15% of dose deviation percentage. As final conclusion, such dosimeter choice and the physical anthropomorphic and anthropometric phantom provided an efficient method for validating radiotherapy protocols. (author)

  2. Phantom dosimetry at 15 MV conformal radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Larissa; Campos, Tarcisio P.R., E-mail: larissathompson@hotmail.com, E-mail: tprcampos@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Minas Gerais, MG (Brazil). Dept. de Engenharia Nuclear; Dias, Humberto G., E-mail: fisicamedica.hl@mariopenna.org.br [Instituto Mario Penna, Minas Gerais, MG (Brazil). Hospital Luxemburgo

    2013-07-01

    The main goal of this work was to evaluate the spatial dose distribution into a tumor simulator inside a head phantom exposed to a 15MV 3D conformal radiation therapy in order to validate internal doses. A head and neck phantom developed by the Ionizing Radiation Research Group (NRI) was used on the experiments. Therapy Radiation planning (TPS) was performed based on those CT images, satisfying a 200 cGy prescribed dose split in three irradiation fields. The TPS assumed 97% of prescribed dose cover the prescribed treatment volume (PTV). Radiochromic films in a solid water phantom provided dose response as a function of optical density. Spatial dosimetric distribution was generated by radiochromic film samples inserted into tumor simulator and brain. The spatial dose profiles held 70 to 120% of the prescribed dose. In spite of the stratified profile, as opposed to the smooth dose profile from TPS, the tumor internal doses were within a 5% deviation from 214.4 cGy evaluated by TPS. 83.2% of the points with a gamma value of less than 1 (3%/3mm) for TPS and experimental values, respectively. At the tumor, a few dark spots in the film caused the appearance of outlier points in 13-15% of dose deviation percentage. As final conclusion, such dosimeter choice and the physical anthropomorphic and anthropometric phantom provided an efficient method for validating radiotherapy protocols. (author)

  3. Stereotactic Body Radiation Therapy for Oligometastatic Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Muldermans, Jonathan L. [F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland (United States); Romak, Lindsay B. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Kwon, Eugene D. [Department of Urology, Mayo Clinic, Rochester, Minnesota (United States); Department of Immunology, Mayo Clinic, Rochester, Minnesota (United States); Park, Sean S. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Olivier, Kenneth R., E-mail: olivier.kenneth@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2016-06-01

    Purpose: To review outcomes of patients with oligometastatic prostate cancer (PCa) treated with stereotactic body radiation therapy (SBRT) and to identify variables associated with local failure. Methods and Materials: We retrospectively reviewed records of patients treated with SBRT for oligometastatic PCa. Metastasis control (ie, control of the treated lesion, MC), biochemical progression-free survival, distant progression-free survival, and overall survival were estimated with the Kaplan-Meier method. Results: Sixty-six men with 81 metastatic PCa lesions, 50 of which were castrate-resistant, were included in the analysis. Lesions were in bone (n=74), lymph nodes (n=6), or liver (n=1). Stereotactic body radiation therapy was delivered in 1 fraction to 71 lesions (88%), at a median dose of 16 Gy (range, 16-24 Gy). The remaining lesions received 30 Gy in 3 fractions (n=6) or 50 Gy in 5 fractions (n=4). Median follow-up was 16 months (range, 3-49 months). Estimated MC at 2 years was 82%. Biochemical progression-free survival, distant progression-free survival, and overall survival were 54%, 45%, and 83%, respectively. On multivariate analysis, only the dose of SBRT was significantly associated with MC; lesions treated with 16 Gy had 58% MC, and those treated with ≥18 Gy had 95% MC at 2 years (P≤.001). At 2 years, MC for lesions treated with 18 Gy (n=21) was 88%. No patient treated with ≥18 Gy in a single fraction or with any multifraction regimen had local failure. Six patients (9%) had grade 1 pain flare, and 2 (3%) had grade 2 pain flare. No grade 2 or greater late toxicities were reported. Conclusions: Stereotactic body radiation therapy for patients with oligometastatic prostate cancer provided optimal metastasis control and acceptable toxicity with doses ≥18 Gy. Biochemical progression-free survival was 54% at 16 months with the inclusion of SBRT in the treatment regimen. Stereotactic body radiation therapy should be considered in

  4. Common-garden studies on adaptive radiation of photosynthetic physiology among Hawaiian lobeliads

    OpenAIRE

    Givnish, Thomas J.; Montgomery, Rebecca A.

    2014-01-01

    Species in an adaptive radiation often occupy different habitats so that individuals of each species develop under different conditions. Showing that a radiation is adaptive thus requires evidence that taxa have diverged genetically and that each has an ecological advantage in using particular habitats or resources, taking into account both phenotypic plasticity and phylogenetic relationships among species. Here, we use a common-garden experiment to show that representative species of Hawaiia...

  5. From dinosaurs to modern bird diversity: extending the time scale of adaptive radiation.

    Directory of Open Access Journals (Sweden)

    Daniel Moen

    2014-05-01

    Full Text Available What explains why some groups of organisms, like birds, are so species rich? And what explains their extraordinary ecological diversity, ranging from large, flightless birds to small migratory species that fly thousand of kilometers every year? These and similar questions have spurred great interest in adaptive radiation, the diversification of ecological traits in a rapidly speciating group of organisms. Although the initial formulation of modern concepts of adaptive radiation arose from consideration of the fossil record, rigorous attempts to identify adaptive radiation in the fossil record are still uncommon. Moreover, most studies of adaptive radiation concern groups that are less than 50 million years old. Thus, it is unclear how important adaptive radiation is over temporal scales that span much larger portions of the history of life. In this issue, Benson et al. test the idea of a "deep-time" adaptive radiation in dinosaurs, compiling and using one of the most comprehensive phylogenetic and body-size datasets for fossils. Using recent phylogenetic statistical methods, they find that in most clades of dinosaurs there is a strong signal of an "early burst" in body-size evolution, a predicted pattern of adaptive radiation in which rapid trait evolution happens early in a group's history and then slows down. They also find that body-size evolution did not slow down in the lineage leading to birds, hinting at why birds survived to the present day and diversified. This paper represents one of the most convincing attempts at understanding deep-time adaptive radiations.

  6. Endoscopic diode laser therapy for chronic radiation proctitis.

    Science.gov (United States)

    Polese, Lino; Marini, Lucia; Rizzato, Roberto; Picardi, Edgardo; Merigliano, Stefano

    2018-01-01

    The purpose of this study is to determine the effectiveness of endoscopic diode laser therapy in patients presenting rectal bleeding due to chronic radiation proctitis (CRP). A retrospective analysis of CRP patients who underwent diode laser therapy in a single institution between 2010 and 2016 was carried out. The patients were treated by non-contact fibers without sedation in an outpatient setting. Fourteen patients (median age 77, range 73-87 years) diagnosed with CRP who had undergone high-dose radiotherapy for prostatic cancer and who presented with rectal bleeding were included. Six required blood transfusions. Antiplatelet (three patients) and anticoagulant (two patients) therapy was not suspended during the treatments. The patients underwent a median of two sessions; overall, a mean of 1684 J of laser energy per session was used. Bleeding was resolved in 10/14 (71%) patients, and other two patients showed improvement (93%). Only one patient, who did not complete the treatment, required blood transfusions after laser therapy; no complications were noted during or after the procedures. Study findings demonstrated that endoscopic non-contact diode laser treatment is safe and effective in CRP patients, even in those receiving antiplatelet and/or anticoagulant therapy.

  7. 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.

  8. Implementation of Remote 3-Dimensional Image Guided Radiation Therapy Quality Assurance for Radiation Therapy Oncology Group Clinical Trials

    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

  9. Intraoperative radiation therapy for breast cancer patients: current perspectives

    Directory of Open Access Journals (Sweden)

    Dutta SW

    2017-04-01

    Full Text Available Sunil W Dutta,1 Shayna L Showalter,2 Timothy N Showalter,1 Bruce Libby,1 Daniel M Trifiletti1 1Department of Radiation Oncology, 2Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA, USA Abstract: Accelerated partial breast irradiation (APBI provides an attractive alternative to whole breast irradiation (WBI through normal tissue radiation exposure and reduced treatment duration. Intraoperative radiation therapy (IORT is a form of APBI with the shortest time interval, as it delivers the entirety of a planned radiation course at the time of breast surgery. However, faster is not always better, and IORT has been met with healthy skepticism. Patients treated with IORT have an increased compliance and overall satisfaction when compared to patients treated with WBI. However, early randomized trial results demonstrated an increased rate of recurrence after IORT, slowing its widespread adoption. Despite these controversies, IORT utilization is increasing nationally and several novel developments are aimed at continuing to minimize the risk of recurrence and treatment-related toxicity while maximizing the patient experience. Keywords: IORT, lumpectomy, breast conservation, electron, photon, evidence

  10. Some strategies of activation therapy using radiations of microwave ranges in experiments on tumorbearing animals

    Directory of Open Access Journals (Sweden)

    Galina V. Zhukova

    2015-11-01

    Full Text Available The paper offers an analysis of activation therapy approaches to an increase in efficacy of antitumor treatment with the use of electromagnetic-nature factors as developed by L.Kh. Garkavi and E.B.Kvakina. Basic principles of optimization of the effects of exposures to electromagnetic radiation in various frequency bands, considering the patterns of development of general unspecific adaptation reactions of the organism as well as conceptual presentation of the organism as a complex nonlinear dissipative system, are described herein. Analyzed are effects of exposure to low-intensity radiationin the millimeter and decimeter wave bands, undertaken according to the above principles, detected in oculated tumor bearing rats. A weak infra-low magnetic field was applied in the study as an additional factor. The experimental study shows a possibility to obtain marked antitumor effects without use of conventional antitumor therapy means.

  11. Has the use of computers in radiation therapy improved the accuracy in radiation dose delivery?

    Science.gov (United States)

    Van Dyk, J.; Battista, J.

    2014-03-01

    Purpose: It is well recognized that computer technology has had a major impact on the practice of radiation oncology. This paper addresses the question as to how these computer advances have specifically impacted the accuracy of radiation dose delivery to the patient. Methods: A review was undertaken of all the key steps in the radiation treatment process ranging from machine calibration to patient treatment verification and irradiation. Using a semi-quantitative scale, each stage in the process was analysed from the point of view of gains in treatment accuracy. Results: Our critical review indicated that computerization related to digital medical imaging (ranging from target volume localization, to treatment planning, to image-guided treatment) has had the most significant impact on the accuracy of radiation treatment. Conversely, the premature adoption of intensity-modulated radiation therapy has actually degraded the accuracy of dose delivery compared to 3-D conformal radiation therapy. While computational power has improved dose calibration accuracy through Monte Carlo simulations of dosimeter response parameters, the overall impact in terms of percent improvement is relatively small compared to the improvements accrued from 3-D/4-D imaging. Conclusions: As a result of computer applications, we are better able to see and track the internal anatomy of the patient before, during and after treatment. This has yielded the most significant enhancement to the knowledge of "in vivo" dose distributions in the patient. Furthermore, a much richer set of 3-D/4-D co-registered dose-image data is thus becoming available for retrospective analysis of radiobiological and clinical responses.

  12. Adaptive plasma for cancer therapy: physics, mechanism and applications

    Science.gov (United States)

    Keidar, Michael

    2017-10-01

    One of the most promising applications of cold atmospheric plasma (CAP) is the cancer therapy. The uniqueness of plasma is in its ability to change composition in situ. Plasma self-organization could lead to formation of coherent plasma structures. These coherent structures tend to modulate plasma chemistry and composition, including reactive species, the electric field and charged particles. Formation of coherent plasma structures allows the plasma to adapt to external boundary conditions, such as different cells types and their contextual tissues. In this talk we will explore possibilities and opportunities that the adaptive plasma therapeutic system might offer. We shall define such an adaptive system as a plasma device that is able to adjust the plasma composition to obtain optimal desirable outcomes through its interaction with cells and tissues. The efficacy of cold plasma in a pre-clinical model of various cancer types such as lung, bladder, breast, head, neck, brain and skin has been demonstrated. Both in-vitro and in-vivo studies revealed that cold plasmas selectively kill cancer cells. Recently mechanism of plasma selectivity based on aquaporin hypothesis has been proposed. Aquaporins (AQPs) are the confirmed membrane channels of H2O2 and other large molecules. We have demonstrated that the anti-cancer capacity of plasma could be inhibited by silencing the expression of AQPs. Additional possible cell feedback mechanism was recently discovered. It is associated with production of reactive species during direct CAP treatment by cancer cells. Selective production of hydrogen peroxide by different cells can lead to adaptation of chemistry at the plasma-cell interface based on the cellular input. In particular we have found that the discharge voltage is an important factor affecting the ratio of reactive oxygen species to reactive nitrogen species in the gas phase and this correlates well with effect of hydrogen peroxide production by cells. This work was

  13. Arc binary intensity modulated radiation therapy (AB IMRT)

    Science.gov (United States)

    Yang, Jun

    The state of the art Intensity Modulate Radiation Therapy (IMRT) has been one of the most significant breakthroughs in the cancer treatment in the past 30 years. There are two types of IMRT systems. The first system is the binary-based tomotherapy, represented by the Peacock (Nomos Corp) and Tomo unit (TomoTherapy Inc.), adopting specific binary collimator leafs to deliver intensity modulated radiation fields in a serial or helical fashion. The other uses the conventional dynamic multileaf collimator (MLC) to deliver intensity modulated fields through a number of gantry positions. The proposed Arc Binary IMRT attempts to deliver Tomo-like IMRT with conventional dynamic MLC and combines the advantages of the two types of IMRT techniques: (1) maximizing the number of pencil beams for better dose optimization, (2) enabling conventional linear accelerator with dynamic MLC to deliver Tomo-like IMRT. In order to deliver IMRT with conventional dynamic MLC in a binary fashion, the slice-by-slice treatment with limited slice thickness has been proposed in the thesis to accommodate the limited MLC traveling speed. Instead of moving the patient to subsequent treatment slices, the proposed method offsets MLC to carry out the whole treatment, slice by slice sequentially, thus avoid patient position error. By denoting one arc pencil beam set as a gene, genetic algorithm (GA) is used as the searching engine for the dose optimization process. The selection of GA parameters is a crucial step and has been studied in depth so that the optimization process will converge with reasonable speed. Several hypothetical and clinical cases have been tested with the proposed IMRT method. The comparison of the dose distribution with other commercially available IMRT systems demonstrates the clear advantage of the new method. The proposed Arc Binary Intensity Modulated Radiation Therapy is not only theoretically sound but practically feasible. The implementation of this method would expand the

  14. Delineation of Supraclavicular Target Volumes in Breast Cancer Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Lindsay C. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Diehn, Felix E. [Department of Radiology, Mayo Clinic, Rochester, Minnesota (United States); Boughey, Judy C. [Department of Surgery, Mayo Clinic, Rochester, Minnesota (United States); Childs, Stephanie K.; Park, Sean S.; Yan, Elizabeth S.; Petersen, Ivy A. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States); Mutter, Robert W., E-mail: mutter.robert@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota (United States)

    2015-07-01

    Purpose: To map the location of gross supraclavicular metastases in patients with breast cancer, in order to determine areas at highest risk of harboring subclinical disease. Methods and Materials: Patients with axial imaging of gross supraclavicular disease were identified from an institutional breast cancer registry. Locations of the metastatic lymph nodes were transferred onto representative axial computed tomography images of the supraclavicular region and compared with the Radiation Therapy Oncology Group (RTOG) breast cancer atlas for radiation therapy planning. Results: Sixty-two patients with 161 supraclavicular nodal metastases were eligible for study inclusion. At the time of diagnosis, 117 nodal metastases were present in 44 patients. Forty-four nodal metastases in 18 patients were detected at disease recurrence, 4 of whom had received prior radiation to the supraclavicular fossa. Of the 161 nodal metastases, 95 (59%) were within the RTOG consensus volume, 4 nodal metastases (2%) in 3 patients were marginally within the volume, and 62 nodal metastases (39%) in 30 patients were outside the volume. Supraclavicular disease outside the RTOG consensus volume was located in 3 regions: at the level of the cricoid and thyroid cartilage (superior to the RTOG volume), in the posterolateral supraclavicular fossa (posterolateral to the RTOG volume), and in the lateral low supraclavicular fossa (lateral to the RTOG volume). Only women with multiple supraclavicular metastases had nodal disease that extended superiorly to the level of the thyroid cartilage. Conclusions: For women with risk of harboring subclinical supraclavicular disease warranting the addition of supraclavicular radiation, coverage of the posterior triangle and the lateral low supraclavicular region should be considered. For women with known supraclavicular disease, extension of neck coverage superior to the cricoid cartilage may be warranted.

  15. Treatment of retinoblastoma by precision megavoltage radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Schipper, J.; Peperzeel, H.A. van (Rijksuniversiteit Utrecht (Netherlands). Academisch Ziekenhuis); Tan, K.E.W.P. (Royal Dutch Eye Hospital, Utrecht, Netherlands)

    1985-02-01

    The principal treatment concept in the Utrecht Retinoblastoma Centre is megavoltage irradiation, followed by light coagulation and/or cryotherapy if there is any doubt as to whether the residual tumour is still active. Radiation therapy is administered by means of a simple but highly accurate temporal beam technique. A standardized dose of 45 Gy is given in 15 fractions of 3 Gy at 3 fractions per week. From 1971 to 1982, 39 children with retinoblastoma have been irradiated in at least one eye. Of the 73 affected eyes, 18 were primarily enucleated, one received light coagulation only, and 54 received radiation therapy. Of the 54 irradiated eyes, 32 were additionally treated by light coagulation and/or cryotherapy for suspicious residual tumour (in 29 eyes), recurrent tumour (in 1 eye), and/or new tumour (in 3 eyes) and 10 were ultimately enucleated. Two eyes also received hyperthermia. The percentages of cure of the irradiated eyes with a minimum follow-up of 2 years were 100% (14/14), 100% (9/9), 83% (10/12), 79% (11/14) and 0% (0/5) in the Reese-Ellsworth groups I to V-A, respectively. Of the saved eyes 95% achieved useful vision. Eighteen eyes developed a clinically detectable radiation cataract; in five of these the lens was aspirated. Cataracts developed exclusively in those lenses of which a posterior portion of more than 1 mm had to be included in the treatment field. The likelihood and the degree of cataract formation was found to be directly related to the dose of radiation to the germinative zone of the lens epithelium. The minimum cataractogenic dose found in this series was 8 Gy.

  16. Solitary plasmacytomas: outcome and prognostic factors after definitive radiation therapy.

    Science.gov (United States)

    Reed, Valerie; Shah, Jatin; Medeiros, L Jeffery; Ha, Chul S; Mazloom, Ali; Weber, Donna M; Arzu, Isidora Y; Orlowski, Robert Z; Thomas, Sheeba K; Shihadeh, Ferial; Alexanian, Raymond; Dabaja, Bouthaina S

    2011-10-01

    The objective of this study was to review the outcome of patients with solitary plasmacytoma (SP) after definitive radiation therapy. The authors retrospectively reviewed 84 patients with SP who were diagnosed and treated at The University of Texas MD Anderson Cancer Center during 1988 to 2008. The impact of tumor anatomic site, tumor size, and the presence of serum and urinary paraprotein at diagnosis was assessed on local control, survival, and the risk of developing multiple myeloma (MM). Fifty-nine patients (70%) had bone SP, and 25 patients (30%) had extramedullary SP. Serum paraprotein was present in 39 patients (46%). The median radiation dose was 45 grays (Gy) (range, 36-53.4 Gy). Local control was achieved in 77 patients (92%). Neither radiation dose nor tumor size predicted local control. The 5-year rate of progression to MM was 47% and was higher for patients with bone SP (56% vs 30% for extramedullary SP; P = .021), and patients who had serum paraprotein detected at diagnosis (60% vs 39%; P = .016). On univariate analysis, patients aged location and serum protein at diagnosis were associated statistically with progression to MM. The 5-year overall survival rate for the entire patient cohort was 78%, and no difference was observed between patients who had bone SP versus extramedullary SP (76% vs 85%, respectively; P = .274). The current results indicated that definitive radiation therapy for SP can provide excellent local control. Progression to MM remains the main problem and is more common among patients with bone SP and those who have serum paraprotein detected at diagnosis. Copyright © 2011 American Cancer Society.

  17. Hyperfractionation radiation therapy in advanced head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Hee; Ye, Ji Won [College of Medicine, Keimyung Univ., Daegu (Korea, Republic of)

    2003-03-01

    The effects of hyperfractionation radiation therapy, such as the failure pattern and survival, on the treatment results in advanced stage head and neck cancer were studied. Between September 1990 and October 1998, 24 patients with advanced stage (III, IV) head and neck cancers, were treated using hyperfractionation radiation therapy in the Department at Radiation Oncology at the Keimyung University Dongsan Medical Center. The male to female ratio was 7 ; 1, and the age range from 38 to 71 years with the median of 56 years. With regard to the TNM stage, 11 patients were stage III and 13 were stage IV. The sites of primary cancer were the nasopharynx in six, the hypopharynx in 6, the larynx in five, the oropharynx in three, the maxillary sinus in three, and the oral cavity in one patient. The radiotherapy was delivered by 6 MV X-ray, with a fraction size of 1.2 Gy at two fractions a day, with at least 6 hours inter-fractional interval. The mean total radiation doses was 72 Gy, (ranging from 64.4 to 76.8 Gy). Fallow-up periods ranged between 3 and 136 months, with the median of 52 months. The overall survival rates at 3 and 5 years in all patients were 66.7% and 52.4%. The disease-free survival rates at 3 and 5 years (3YDFS, 5YDFS) in all patients Were 66.7% and 47.6%. The 3YDFS and 5YDFS in stage III patients were 81.8% and 63.6%, and those in stage IV patients were 53.8% and 32.3%. Ten patients were alive with no local nor distant failures at the time of analyses. Six patients (25%) died due to distant metastasis and 12.5% died due to local failure. Distant metastasis was the major cause of failure, but 2 patients died due to unknown failures and 3 of other diseases. The distant metastasis sites were the lung (3 patients), the bone (1 patient), and the liver (2 patients). One patient died of second esophageal cancer. There were no severe late complications, with the exception of 1 osteoradionecrosis of the mandible 58 months after treatment. Although this study was

  18. Extrapleural pneumonectomy, photodynamic therapy and intensity modulated radiation therapy for the treatment of malignant pleural mesothelioma.

    Science.gov (United States)

    Du, Kevin L; Both, Stefan; Friedberg, Joseph S; Rengan, Ramesh; Hahn, Stephen M; Cengel, Keith A

    2010-09-01

    Intensity modulated radiation therapy (IMRT) has recently been proposed for the treatment of malignant pleural mesothelioma (MPM). Here, we describe our experience with a multimodality approach for the treatment of mesothelioma, incorporating extrapleural pneumonectomy, intraoperative photodynamic therapy and postoperative hemithoracic IMRT. From 2004-2007, we treated 11 MPM patients with hemithoracic IMRT, 7 of whom had undergone porfimer sodium-mediated PDT as an intraoperative adjuvant to surgical debulking. The median radiation dose to the planning treatment volume (PTV) ranged from 45.4-54.5 Gy. For the contralateral lung, V20 ranged from 1.4-28.5%, V5 from 42-100% and MLD from 6.8-16.5 Gy. In our series, 1 patient experienced respiratory failure secondary to radiation pneumonitis that did not require mechanical ventilation. Multimodality therapy combining surgery with increased doses of radiation using IMRT, and newer treatment modalities such as PDT , appears safe. Future prospective analysis will be needed to demonstrate efficacy of this approach in the treatment of malignant mesothelioma. Efforts to reduce lung toxicity and improve dose delivery are needed and provide the promise of improved local control and quality of life in a carefully chosen multidisciplinary approach.

  19. Linear algebraic methods applied to intensity modulated radiation therapy.

    Science.gov (United States)

    Crooks, S M; Xing, L

    2001-10-01

    Methods of linear algebra are applied to the choice of beam weights for intensity modulated radiation therapy (IMRT). It is shown that the physical interpretation of the beam weights, target homogeneity and ratios of deposited energy can be given in terms of matrix equations and quadratic forms. The methodology of fitting using linear algebra as applied to IMRT is examined. Results are compared with IMRT plans that had been prepared using a commercially available IMRT treatment planning system and previously delivered to cancer patients.

  20. 3D measurement of absolute radiation dose in grid therapy

    Science.gov (United States)

    Trapp, J. V.; Warrington, A. P.; Partridge, M.; Philps, A.; Leach, M. O.; Webb, S.

    2004-01-01

    Spatially fractionated radiotherapy through a grid is a concept which has a long history and was routinely used in orthovoltage radiation therapy in the middle of last century to minimize damage to the skin and subcutaneous tissue. With the advent of megavoltage radiotherapy and its skin sparing effects the use of grids in radiotherapy declined in the 1970s. However there has recently been a revival of the technique for use in palliative treatments with a single fraction of 10 to 20 Gy. In this work the absolute 3D dose distribution in a grid irradiation is measured for photons using a combination of film and gel dosimetry.

  1. Image-guided radiation therapy. Paradigm change in radiation therapy; Bildgestuetzte Strahlentherapie. Paradigmenwechsel in der Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Wenz, F. [Universitaetsmedizin Mannheim der Universitaet Heidelberg, Klinik fuer Strahlentherapie und Radioonkologie, Mannheim (Germany); Belka, C. [Klinikum der Ludwig-Maximilians-Universitaet, Klinik fuer Strahlentherapie und Radioonkologie, Muenchen (Germany); Reiser, M. [Klinikum der Ludwig-Maximilians-Universitaet, Institut fuer Klinische Radiologie, Muenchen (Germany); Schoenberg, S.O. [Universitaetsmedizin Mannheim der Universitaet Heidelberg, Institut fuer Klinische Radiologie und Nuklearmedizin, Mannheim (Germany)

    2012-03-15

    The introduction of image-guided radiotherapy (IGRT) has changed the workflow in radiation oncology more dramatically than any other innovation in the last decades. Imaging for treatment planning before the initiation of the radiotherapy series does not take alterations in patient anatomy and organ movement into account. The principle of IGRT is the temporal and spatial connection of imaging in the treatment position immediately before radiation treatment. The actual position and the target position are compared using cone-beam computed tomography (CT) or stereotactic ultrasound. The IGRT procedure allows a reduction of the safety margins and dose to normal tissue without an increase in risk of local recurrence. In the future the linear treatment chain in radiation oncology will be developed based on the closed-loop feedback principle. The IGRT procedure is increasingly being used especially for high precision radiotherapy, e.g. for prostate or brain tumors. (orig.) [German] Die Einfuehrung der bildgestuetzten Radiotherapie (IGRT - ''image-guided radiotherapy'') hat wie kaum eine andere Innovation die Behandlungsablaeufe in der Radioonkologie veraendert. Eine einmalige Bildgebung zur Bestrahlungsplanung vor der Behandlungsserie beruecksichtigt nicht die Aenderung der Patientengeometrie und die Organbeweglichkeit. Das Prinzip der IGRT besteht in der raeumlichen und zeitlichen Zusammenfuehrung von Bildgebung in der Bestrahlungsposition unmittelbar vor der eigentlichen Bestrahlung. Mittels Cone-beam-CT oder stereotaktischem Ultraschall wird die Ist- mit der Sollposition verglichen. Die IGRT erlaubt die Reduktion der Sicherheitssaeume und damit die Schonung des Normalgewebes, ohne das Rezidivrisiko zu erhoehen. Zukuenftig wird die lineare Behandlungskette in der Radioonkologie durch eine geschlossene, multipel rueckgekoppelte Therapieschleife ersetzt werden. Speziell bei Praezisionsbestrahlungen wie z. B. Prostata- oder Hirntumoren kommt die IGRT

  2. 21 CFR 892.5770 - Powered radiation therapy patient support assembly.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Powered radiation therapy patient support assembly. 892.5770 Section 892.5770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... therapy patient support assembly. (a) Identification. A powered radiation therapy patient support assembly...

  3. Therapy of patients with osteoarthritis with low energy laser radiation

    Directory of Open Access Journals (Sweden)

    L. V. Vasiljeva

    2008-01-01

    Full Text Available Objective. To assess influence oflow energy laser radiation (LELR on glycosaminoglycan (GAG and vitamin С level in pts with osteoarthritis (OA. Material and methods. 82 pts with primary OA and 25 healthy volunteers signed informed consent were included in an open randomized prospective 12-month study. Inclusion criteria: unsatisfactory effect of previous drug therapy (DT, stable NSAID dose 3-5 days before and during LELR course, absence of comorbid hepatic and kidney diseases in stage of functional decompensation, malignant diseases, exclusion therapy influencing microcirculation, exercise therapy, physical therapy. Intra-articular injections were not done during 3 months before the study. Pts were divided into 2 groups. Group 1 received complex DT and LELR, group 2 - DT. clinical and laboratory parameters were used as efficacy measures. Statistical analysis was performed on personal computer IBM PC (OS — Windows EP Home Edition with Microsoft office and STATISTICA 6.0 programs. Results. Analysis of the results showed significant improvement of most measures in comparison with traditional DT. LELR administration allowed to decrease chondroprotector and NSAID doses. Vitamin С decrease in serum of OA pts may be a risk factor of development and progression of this disease.

  4. Bioluminescence Tomography–Guided Radiation Therapy for Preclinical Research

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bin [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland (United States); Wang, Ken Kang-Hsin, E-mail: kwang27@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland (United States); Yu, Jingjing [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland (United States); School of Physics and Information Technology, Shaanxi Normal University, Shaanxi (China); Eslami, Sohrab; Iordachita, Iulian [Laboratory for Computational Sensing and Robotics, Johns Hopkins University, Baltimore, Maryland (United States); Reyes, Juvenal; Malek, Reem [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland (United States); Tran, Phuoc T. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland (United States); Department of Oncology and Urology, Brady Urological Institute, Johns Hopkins University, Baltimore, Maryland (United States); Patterson, Michael S. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario (Canada); Wong, John W. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins School of Medicine, Baltimore, Maryland (United States)

    2016-04-01

    Purpose: In preclinical radiation research, it is challenging to localize soft tissue targets based on cone beam computed tomography (CBCT) guidance. As a more effective method to localize soft tissue targets, we developed an online bioluminescence tomography (BLT) system for small-animal radiation research platform (SARRP). We demonstrated BLT-guided radiation therapy and validated targeting accuracy based on a newly developed reconstruction algorithm. Methods and Materials: The BLT system was designed to dock with the SARRP for image acquisition and to be detached before radiation delivery. A 3-mirror system was devised to reflect the bioluminescence emitted from the subject to a stationary charge-coupled device (CCD) camera. Multispectral BLT and the incomplete variables truncated conjugate gradient method with a permissible region shrinking strategy were used as the optimization scheme to reconstruct bioluminescent source distributions. To validate BLT targeting accuracy, a small cylindrical light source with high CBCT contrast was placed in a phantom and also in the abdomen of a mouse carcass. The center of mass (CoM) of the source was recovered from BLT and used to guide radiation delivery. The accuracy of the BLT-guided targeting was validated with films and compared with the CBCT-guided delivery. In vivo experiments were conducted to demonstrate BLT localization capability for various source geometries. Results: Online BLT was able to recover the CoM of the embedded light source with an average accuracy of 1 mm compared to that with CBCT localization. Differences between BLT- and CBCT-guided irradiation shown on the films were consistent with the source localization revealed in the BLT and CBCT images. In vivo results demonstrated that our BLT system could potentially be applied for multiple targets and tumors. Conclusions: The online BLT/CBCT/SARRP system provides an effective solution for soft tissue targeting, particularly for small, nonpalpable, or

  5. Sequential estrogen and radiation therapy for stage C prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tachibana, Yuichi; Kawai, Tsuneo; Kobayashi, Tsuyoshi; Yamauchi, Tamio; Aizawa, Taku (Japanese Foundation for Cancer Research, Tokyo (Japan). Hospital)

    1993-03-01

    Twenty of 34 stage C cases have been treated by sequential estrogen and radiation in our hospital between 1980 and 1989 and half of them had actually been done staging operation. An average age was 69.3. Tumor differentiations were distributed well in 5 cases, moderately in 5 and poorly in 9. The other unknown differentiation case was diagnosed by fine needle aspiration cytology. Previously administered estrogens were diethylstilbestrol diphosphate in 15 cases and others in 5. Total doses of 70 Gy in 35 fractions were sequentially delivered to the prostate, involving if necessary the seminal vesicles over a seven-week period by bilateral 120deg pendel using linear accelerator. Radiation field was sized from 6 x 6 to 8 x 8 cm. Estrogens have been continuously administered following radiation in 11 cases. Therapeutic effects upon the prostate were evaluated by digital rectal palpation. Improvement rate and atrophy rate of the primary lesion were 94.4% and 50% respectively. Recurrences were observed in 4 cases and 3 of them recurred within 3 years after initiation of the treatment. Recurred sites were in primary lesion in 2 cases and in bone in two. Five year non-recurrence rate was 81% by Kaplan Meier's method. One of 3 who discontinued hormone administration during or immediately after radiotherapy had local recurrence after 65 months and the other 2 cases died of gastric cancer and unknown cause. Causes of 6 dead cases were one prostate cancer, one gastric cancer, one heart failure, one pneumonia and 2 unknown. The cancer death rate was 25% (1/4 cases). Five year cumulative survival rate by Kaplan-Meier's method was 59.0%. Our results support the view that the sequential estrogen and radiation therapy for the pathological stage C patients of the prostate cancer may be as preferable as radiation alone for the treatment of stage B prostate cancer. (J.P.N.).

  6. Radionuclides in radiation-induced bystander effect; may it share in radionuclide therapy?

    Science.gov (United States)

    Widel, M

    2017-01-01

    For many years in radiobiology and radiotherapy predominated the conviction that cellular DNA is the main target for ionizing radiation, however, the view has changed in the past 20 years. Nowadays, it is assumed that not only directed (targeted) radiation effect, but also an indirect (non-targeted) effect may contribute to the result of radiation treatment. Non-targeted effect is relatively well recognized after external beam irradiation in vitro and in vivo, and comprises such phenomena like radiation-induced bystander effect (RIBE), genomic instability, adaptive response and abscopal (out of field) effect. These stress-induced and molecular signaling mediated phenomena appear in non-targeted cells as variety responses resembling that observed in directly hit cells. Bystander effects can be both detrimental and beneficial in dependence on dose, dose-rate, cell type, genetic status and experimental condition. Less is known about radionuclide-induced non-targeted effects in radionuclide therapy, although, based on characteristics of the radionuclide radiation, on experiments in vitro utilizing classical and 3-D cell cultures, and preclinical study on animals it seems obvious that exposure to radionuclide is accompanied by various bystander effects, mostly damaging, less often protective. This review summarizes existing data on radionuclide induced bystander effects comprising radionuclides emitting beta- and alpha-particles and Auger electrons used in tumor radiotherapy and diagnostics. So far, separation of the direct effect of radionuclide decay from crossfire and bystander effects in clinical targeted radionuclide therapy is impossible because of the lack of methods to assess whether, and to what extent bystander effect is involved in human organism. Considerations on this topic are also included.

  7. [Functional insulin therapy courses adapted to the patient's reality].

    Science.gov (United States)

    Ruiz, J; Morel, D; Andrey, M; Masciotra, D

    2011-06-08

    Therapeutic education was initially developed in the field of diabetology. In this chronic disease, it is the patient who is the major decision-maker. R. K. Bernstein is probably the first patient to have practised self glucose monitoring. He developed the basal-bolus technique for himself, which prompted the creation of functional insulin therapy courses by European physicians. This experiential approach has been adapted and simplified for patients in order to facilitate their management of uncertainty. The ASKAR method offers a frame of reference for the development of teaching-learning sequences. The acronym ASKAR refers to the five components of a person's experience: Action, Situation, Knowledge, Attitude and Resource. Working on these five components is a way for patients to improve their management of uncertainty.

  8. Learning to speciate: The biased learning of mate preferences promotes adaptive radiation.

    Science.gov (United States)

    Gilman, R Tucker; Kozak, Genevieve M

    2015-11-01

    Bursts of rapid repeated speciation called adaptive radiations have generated much of Earth's biodiversity and fascinated biologists since Darwin, but we still do not know why some lineages radiate and others do not. Understanding what causes assortative mating to evolve rapidly and repeatedly in the same lineage is key to understanding adaptive radiation. Many species that have undergone adaptive radiations exhibit mate preference learning, where individuals acquire mate preferences by observing the phenotypes of other members of their populations. Mate preference learning can be biased if individuals also learn phenotypes to avoid in mates, and shift their preferences away from these avoided phenotypes. We used individual-based computational simulations to study whether biased and unbiased mate preference learning promotes ecological speciation and adaptive radiation. We found that ecological speciation can be rapid and repeated when mate preferences are biased, but is inhibited when mate preferences are learned without bias. Our results suggest that biased mate preference learning may play an important role in generating animal biodiversity through adaptive radiation. © 2015 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  9. A goal-based angular adaptivity method for thermal radiation modelling in non grey media

    Science.gov (United States)

    Soucasse, Laurent; Dargaville, Steven; Buchan, Andrew G.; Pain, Christopher C.

    2017-10-01

    This paper investigates for the first time a goal-based angular adaptivity method for thermal radiation transport, suitable for non grey media when the radiation field is coupled with an unsteady flow field through an energy balance. Anisotropic angular adaptivity is achieved by using a Haar wavelet finite element expansion that forms a hierarchical angular basis with compact support and does not require any angular interpolation in space. The novelty of this work lies in (1) the definition of a target functional to compute the goal-based error measure equal to the radiative source term of the energy balance, which is the quantity of interest in the context of coupled flow-radiation calculations; (2) the use of different optimal angular resolutions for each absorption coefficient class, built from a global model of the radiative properties of the medium. The accuracy and efficiency of the goal-based angular adaptivity method is assessed in a coupled flow-radiation problem relevant for air pollution modelling in street canyons. Compared to a uniform Haar wavelet expansion, the adapted resolution uses 5 times fewer angular basis functions and is 6.5 times quicker, given the same accuracy in the radiative source term.

  10. Current status of radiation therapy. Evidence-based medicine (EBM) of radiation therapy. Radiotherapy for pharyngeal and laryngeal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chatani, Masashi [Osaka Rosai Hospital, Sakai (Japan)

    2002-03-01

    Radiation therapy is the first choice of treatment for early pharyngeal and laryngeal cancers, especially those of the glotic larynx and nasopharynx. For advanced lesions without distant metastasis, more intensive treatments, i.e., chemoradiotherapy, multiple fractions per day, and conformal radiotherapy are introduced to improve local control and survival. However, the level of evidence-based medicine is different for each treatment modality. In this review, recent reports of radiotherapy for pharyngeal and laryngeal cancer are introduced from the point of view of the evidence level. (author)

  11. Adjuvant radiation therapy in metastatic lymph nodes from melanoma

    Directory of Open Access Journals (Sweden)

    Penel Nicolas

    2011-02-01

    Full Text Available Abstract Purpose To analyze the outcome after adjuvant radiation therapy with standard fractionation regimen in metastatic lymph nodes (LN from cutaneous melanoma. Patients and methods 86 successive patients (57 men were treated for locally advanced melanoma in our institution. 60 patients (69% underwent LN dissection followed by radiation therapy (RT, while 26 patients (31% had no radiotherapy. Results The median number of resected LN was 12 (1 to 36 with 2 metastases (1 to 28. Median survival after the first relapse was 31.8 months. Extracapsular extension was a significant prognostic factor for regional control (p = 0.019. Median total dose was 50 Gy (30 to 70 Gy. A standard fractionation regimen was used (2 Gy/fraction. Median number of fractions was 25 (10 to 44 fractions. Patients were treated with five fractions/week. Patients with extracapsular extension treated with surgery followed by RT (total dose ≥50 Gy had a better regional control than patients treated by surgery followed by RT with a total dose Conclusion Adjuvant radiotherapy was able to increase regional control in targeted sub-population (LN with extracapsular extension.

  12. Subacute brain atrophy after radiation therapy for malignant brain tumor

    Energy Technology Data Exchange (ETDEWEB)

    Asai, A.; Matsutani, M.; Kohno, T.; Nakamura, O.; Tanaka, H.; Fujimaki, T.; Funada, N.; Matsuda, T.; Nagata, K.; Takakura, K.

    1989-05-15

    Brain atrophy with mental and neurologic deterioration developing a few months after radiation therapy in patients without residual or recurrent brain tumors has been recognized. Two illustrative case reports of this pathologic entity are presented. Six autopsy cases with this entity including the two cases were reviewed neurologically, radiographically, and histopathologically. All patients presented progressive disturbances of mental status and consciousness, akinesia, and tremor-like involuntary movement. Computerized tomography (CT) demonstrated marked enlargement of the ventricles, moderate widening of the cortical sulci, and a moderately attenuated CT number for the white matter in all six patients. Four of the six patients had CSF drainage (ventriculoperitoneal shunt or continuous lumbar drainage), however, none of them improved. Histologic examination demonstrated swelling and loss of the myelin sheath in the white matter in all patients, and reactive astrocytosis in three of the six patients. Neither prominent neuronal loss in the cerebral cortex or basal ganglia, nor axonal loss in the white matter was generally identified. The blood vessels of the cerebral cortex and white matter were normal. Ependymal layer and the surrounding brain tissue were normal in all patients. These findings suggested that this pathologic condition results from demyelination secondary to direct neurotoxic effect of irradiation. The authors' previous report was reviewed and the differential diagnoses, the risk factors for this pathologic entity, and the indication for radiation therapy in aged patients with a malignant brain tumor are discussed.

  13. Sexual function after surgical and radiation therapy for cervical carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Seibel, M. (Beth Israel Hospital, Boston, MA); Freeman, M.G.; Graves, W.L.

    1982-10-01

    One hundred women treated for carcinoma of the cervix were interviewed more than one year later to establish the effects of radiation or surgical therapy on sexual function. Forty-three had received irradiation, 44 nonradical surgery, six combined surgery and irradiation, and seven radical surgery. The irradiation and nonradical surgery groups were each further subdivided into subgroups of patients aged 30 to 49 for age-controlled comparison. Patients in the irradiation group had statistically significant decreases in sexual enjoyment, ability to attain orgasm, coital opportunity, frequency of intercourse, and coital desire. The group who had nonradical surgical procedures had no significant change in sexual function after treatment. Similar results were found in both age-controlled subgroups, eliminating age as a major etiologic factor. Marked vaginal alterations were recorded in the majority of irradiated patients, but were not present among the groups treated with nonradical surgery. The vaginal changes alone could not be held accountable for the significant decrease in sexual function among women who received pelvic irradiation. The origin of decreased sexual desire after radiation therapy is complex, and not yet completely understood. We propose therapeutic programs to help women deal with the emotional and physical consequences of pelvic irradiation.

  14. Late Effects of Radiation Therapy in Pediatric Cancer Survivors.

    Science.gov (United States)

    Arain, Abeer; Herman, Terence; Matthiesen, Chance

    2015-04-01

    The overall survival rates of many pediatric cancers continue to improve with each decade due to new advances in therapy. As this trend continues, the focus and importance of minimizing acute and long-term toxicity associated with treatment is paramount. While significant research regarding many of the late responses of normal tissues associated with radiation exposure has been established, future endeavors must be directed toward the identification of therapy related factors including radiation total dose, dose rate, exposure, and target treatment volumes. Awareness of short and long-term health risks of these patients is important and careful follow-up of long-term survivors is essential. In this report, we review some selected late adverse effects including the development of secondary malignancies, cardiotoxicity, physiological changes to glandular tissue, hormonal and reproductive changes to germ cells, and neurocognitive changes. Furthermore, we compared the differences regarding late effects of normal tissues associated with the use of proton versus photon radiotherapy, a topic that has received a great deal of attention in pediatric cancer and is increasing in utilization in the United States and world-wide.

  15. Ion chambers compliance results of Brazilian radiation therapy facilities.

    Science.gov (United States)

    Joana, Georgia Santos; Salata, Camila; Leal, Paulo; Oliveira, Renato; Couto, Nozimar do; Teixeira, Flavia Cristina; Soares, Abner Duarte; Santini, Eduardo Sergio; Gonçalves, Marcello Gomes

    2017-12-07

    Brazilian Nuclear Energy Commission (cnen) has been making a constant effort to keep updated with international standards and national needs to strengthen the status of radiological protection of the country. The guidelines related to radiation therapy facilities have been revised in the last five years in order to take in consideration the most relevant aspects of the growing technology as well as to mitigate the accidents or incidents observed in practice. Hence, clinical dosimeters have gained special importance in this matter. In the present work we discuss the effectiveness of regulation and inspections to the enforcement of instrument calibration accuracy for improvement of patient dosimetry and quality control. As a result, we observed that the number of calibrated instruments, mainly well-chambers, is increasing each year. The same behavior is observed for instruments employed in technologically advanced radiation treatments such as intensity modulated radiotherapy (imrt), volumetric therapy and stereotatic radiosurgery (srs). We ascribe this behavior to the new regulation. © 2017 IOP Publishing Ltd.

  16. Surgical procedures for digestive fistulae caused by radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Satoshi; Honda, Ichiro; Watanabe, Kazuo; Nagata, Matsuo; Yamamoto, Hiroshi; Soda, Hiroaki; Tasaki, Kentaro [Chiba Cancer Center Hospital (Japan)

    2002-09-01

    We evaluated the effectiveness of surgery to treat ileal fistulations associated with radiation exposure. An ileal fistula developed in eight patients, 13-102 months after 60 Gy of irradiation to the pelvic cavity, given as initial treatment or supportive therapy following resection of the primary tumor. The underlying diseases were cervical cancer in seven women and bladder cancer in one man. Two patients had an ileorectal fistula, two had an ileosigmoidal fistula, three had an ileovesical fistula, and one had an ileourethral fistula. We performed a partial enterectomy in one patient, a simple bypass operation without exclusion in one, and bypass operations with exclusion in the other six. Intestinal expansion in the exclusion site occurred in one patient, but there were no other complications related directly to surgery, such as sutural insufficiency. The patient who underwent a simple bypass operation died of emaciation 2 months after the surgery, but all of the other patients were discharged capable of oral ingestion. Our findings showed that surgery was beneficial for alleviating the various conditions related to digestive fistulation following radiation therapy. (author)

  17. Enhanced Radiation Therapy of Gold Nanoparticles in Liver Cancer

    Directory of Open Access Journals (Sweden)

    Meili Guo

    2017-03-01

    Full Text Available Gold nanoparticles (GNPs were widely used in X-ray imaging and radiation therapy due to strong photoelectric effects and secondary electrons under high energy irradiation. As liver cancer is one of the most common forms of cancer, the use of GNPs could enhance liver cancer radiotherapy. We synthesized polyethylene glycol (PEG-coated GNPs of two different sizes by chemical reduction reaction. Blood stability, cellular uptake, cytotoxicity and radiation therapy were investigated. A 3–5 nm red shift of SPR caused by interactions between PEG-coated GNPs and plasma indicated their good stability. Cellular uptake assay showed that PEG-coated GNPs would enhance an appreciable uptake. GNPs preferred to combine with blood proteins, and thus induced the formation of 30–50 nm Au-protein corona. GNPs were endocytosed by cytoplasmic vesicles, localized in intracellular region, and presented concentration dependent cell viability. Clonogenic assay illustrated that the PEG-coated GNPs could sensitize two liver cancer cell lines to irradiation.

  18. Automatic Organ Localization for Adaptive Radiation Therapy for Prostate Cancer

    Science.gov (United States)

    2005-05-01

    13 716-724 Zou K H, Warfield S K, Baharatha A, Tempany C, Kaus M R, Haker S J, Wells W M, Jolesz F A and Kikinis R 2004 Statistical validation of image segmentation quality based on a spatial overlap index Academic Radiology 11 178-189

  19. Diversity and disparity through time in the adaptive radiation of Antarctic notothenioid fishes.

    Science.gov (United States)

    Colombo, M; Damerau, M; Hanel, R; Salzburger, W; Matschiner, M

    2015-02-01

    According to theory, adaptive radiation is triggered by ecological opportunity that can arise through the colonization of new habitats, the extinction of antagonists or the origin of key innovations. In the course of an adaptive radiation, diversification and morphological evolution are expected to slow down after an initial phase of rapid adaptation to vacant ecological niches, followed by speciation. Such 'early bursts' of diversification are thought to occur because niche space becomes increasingly filled over time. The diversification of Antarctic notothenioid fishes into over 120 species has become one of the prime examples of adaptive radiation in the marine realm and has likely been triggered by an evolutionary key innovation in the form of the emergence of antifreeze glycoproteins. Here, we test, using a novel time-calibrated phylogeny of 49 species and five traits that characterize notothenioid body size and shape as well as buoyancy adaptations and habitat preferences, whether the notothenioid adaptive radiation is compatible with an early burst scenario. Extensive Bayesian model comparison shows that phylogenetic age estimates are highly dependent on model choice and that models with unlinked gene trees are generally better supported and result in younger age estimates. We find strong evidence for elevated diversification rates in Antarctic notothenioids compared to outgroups, yet no sign of rate heterogeneity in the course of the radiation, except that the notothenioid family Artedidraconidae appears to show secondarily elevated diversification rates. We further observe an early burst in trophic morphology, suggesting that the notothenioid radiation proceeds in stages similar to other prominent examples of adaptive radiation. © 2014 The Authors. Journal of Evolutionary Biology published by John Wiley & Sons Ltd on behalf of European Society for Evolutionary Biology.

  20. Usefulness of radiation treatment planning allpied respiration factor for streotatic body radiation therapy in the lung cancer

    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.

  1. [New strategies to interfere with radiation response: "biomodulation" of radiation therapy].

    Science.gov (United States)

    Deutsch, E; Kaliski, A; Maggiorella, L; Bourhis, J

    2005-03-01

    The development of several new anti cancer agents has been made possible because of recent significant achievements in our global understanding of cancer biology. These new "targeted" agents selectively inhibit targets necessary for tumor cell growth and viability with little toxicity to normal cells compared to conventional cytotoxic agents. So far, the efficacy of many of these new promising agents when used alone treatment remains limited, it is likely that the optimal use of these agents could be obtained in combination with conventional agents such as radiation therapy. The potential benefit of these targeted therapies combined with irradiation seems important. They might offer the advantage of increasing the tumor response to radiation with no or little increase in normal tissue damage. Therefore, these new types of chemo-radiation approaches might respect the normal tissue versus tumor cell "therapeutic ratio". These approaches can be sub divided in three sub groups: 1) Therapeutics targeting selectively one tumor related biochemical activity such as EGFR inhibitors. These approaches are efficient but one mutation of the target might render them inefficient. 2) Therapeutics directed against a widely expressed target. This is the case for anti Insulin Growth Factor-1 (IGF1R) interventions: IGF1R inhibition seems to specifically alter tumor cell viability with a minimal effect on normal cells viability. 3) Strategies which are not targeted against the tumor but the microenvironment, especially angiogenesis. This type of approaches seems to be applicable independently of tumor intrinsic biologic related factors.

  2. Ultrasound Thermometry for Therapy-level Radiation Dosimetry

    Science.gov (United States)

    Taylor, Courtney

    2010-03-01

    Radiation oncology is the process of administering a specified dose of radiation to a patient currently receiving treatment for a form of cancer. In this process, it is vital to know the delivered dose for a given radiation beam to correctly treat a patient. The primary reference standard for absorbed dose is established using water calorimetry. The absorbed dose, typically of order 1 Gy (J/kg) at therapy levels, is realized by measuring sub-millikelvin temperature changes using a thermistor in a sensitive Wheatstone bridge. Ultrasound technology has been investigated as an alternative to thermistor measurements since the speed of sound propagation in water varies with temperature. With ultrasonic time-of-flight and highly sensitive phase detection techniques, temperature sensitivity comparable to that of the thermistor bridge has been achieved without introducing non-water materials into the test area. A single ultrasound transducer transmitting and receiving at 5.0 MHz throughout the length of the water phantom, and the phase change of the sound wave was used to determine temperature increase from an irradiative source at specified depths of the phantom. In this experiment, the exposure period was varied from 15s to 160s cyclically by modulating a heat lamp, and a profile of the measured temperature response as a function of the period was obtained using Fourier analysis. Due to the large temperature gradient in the water phantom, measurements are prone to convection which was indeed observed and will be discussed.

  3. Therapeutic Implications for Overcoming Radiation Resistance in Cancer Therapy

    Science.gov (United States)

    Kim, Byeong Mo; Hong, Yunkyung; Lee, Seunghoon; Liu, Pengda; Lim, Ji Hong; Lee, Yong Heon; Lee, Tae Ho; Chang, Kyu Tae; Hong, Yonggeun

    2015-01-01

    Ionizing radiation (IR), such as X-rays and gamma (γ)-rays, mediates various forms of cancer cell death such as apoptosis, necrosis, autophagy, mitotic catastrophe, and senescence. Among them, apoptosis and mitotic catastrophe are the main mechanisms of IR action. DNA damage and genomic instability contribute to IR-induced cancer cell death. Although IR therapy may be curative in a number of cancer types, the resistance of cancer cells to radiation remains a major therapeutic problem. In this review, we describe the morphological and molecular aspects of various IR-induced types of cell death. We also discuss cytogenetic variations representative of IR-induced DNA damage and genomic instability. Most importantly, we focus on several pathways and their associated marker proteins responsible for cancer resistance and its therapeutic implications in terms of cancer cell death of various types and characteristics. Finally, we propose radiation-sensitization strategies, such as the modification of fractionation, inflammation, and hypoxia and the combined treatment, that can counteract the resistance of tumors to IR. PMID:26569225

  4. Therapeutic Implications for Overcoming Radiation Resistance in Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Byeong Mo Kim

    2015-11-01

    Full Text Available Ionizing radiation (IR, such as X-rays and gamma (γ-rays, mediates various forms of cancer cell death such as apoptosis, necrosis, autophagy, mitotic catastrophe, and senescence. Among them, apoptosis and mitotic catastrophe are the main mechanisms of IR action. DNA damage and genomic instability contribute to IR-induced cancer cell death. Although IR therapy may be curative in a number of cancer types, the resistance of cancer cells to radiation remains a major therapeutic problem. In this review, we describe the morphological and molecular aspects of various IR-induced types of cell death. We also discuss cytogenetic variations representative of IR-induced DNA damage and genomic instability. Most importantly, we focus on several pathways and their associated marker proteins responsible for cancer resistance and its therapeutic implications in terms of cancer cell death of various types and characteristics. Finally, we propose radiation-sensitization strategies, such as the modification of fractionation, inflammation, and hypoxia and the combined treatment, that can counteract the resistance of tumors to IR.

  5. Predictors of overall satisfaction of cancer patients undergoing radiation therapy

    Directory of Open Access Journals (Sweden)

    Becker-Schiebe M

    2015-09-01

    Full Text Available Martina Becker-Schiebe,1,2 Uwe Pinkert,1 Tahera Ahmad,1 Christof Schäfer,3 Wolfgang Hoffmann,1 Heiko Franz4 1Department of Radiotherapy and Radio-Oncology, Städtisches Klinikum Braunschweig gGmbH, Braunschweig, 2Radiation Oncology, Hannover Medical School, Hannover, 3Radiation Oncology Straubing, University of Regensburg, Regensburg, 4Department of Gynecology and Obstetrics, Städtisches Klinikum Braunschweig gGmbH, Braunschweig, Germany Background: Reporting the experiences and satisfaction of patients, as well as their quality of care scores is an emerging recommendation in health care systems. Many aspects of patients’ experience determine their overall satisfaction. The aim of this evaluation was to define the main factors contributing to the satisfaction of patients undergoing radiotherapy in an outpatient setting. Patients and methods: A total of 1,710 patients with a histologically proven cancer, who were treated in our department between 2012 and 2014, were recruited for this prospective evaluation. At the end of therapy, each patient was asked to grade the skills and the care provided by radiation therapists, physicians, and physician’s assistants, as well as the overall satisfaction during therapy. Statistical analysis was performed to determine which parameters had the greatest influence on overall satisfaction. Results: Overall satisfaction with the provided care was high with a mean satisfaction score of 1.4. Significant correlations were found between overall satisfaction and each of the following survey items: courtesy, protection of privacy, professional skills and care provided by the radiation therapists and physicians, accuracy of provided information, and cleanliness. Linear regression analysis demonstrated that courteous behavior and the protection of privacy were the strongest predictors for overall satisfaction (P<0.001, followed by care and skills of physicians and radiation therapists. Patients suffering from head

  6. Hyperbaric Oxygen Therapy for Radiation-Induced Cystitis and Proctitis

    Energy Technology Data Exchange (ETDEWEB)

    Oliai, Caspian; Fisher, Brandon; Jani, Ashish; Wong, Michael; Poli, Jaganmohan; Brady, Luther W. [Department of Radiation Oncology, Drexel University College of Medicine, Philadelphia, Pennsylvania (United States); Komarnicky, Lydia T., E-mail: lydia.komarnicky-kocher@drexelmed.edu [Department of Radiation Oncology, Drexel University College of Medicine, Philadelphia, Pennsylvania (United States)

    2012-11-01

    Purpose: To provide a retrospective analysis of the efficacy of hyperbaric oxygen therapy (HBOT) for treating hemorrhagic cystitis (HC) and proctitis secondary to pelvic- and prostate-only radiotherapy. Methods and Materials: Nineteen patients were treated with HBOT for radiation-induced HC and proctitis. The median age at treatment was 66 years (range, 15-84 years). The range of external-beam radiation delivered was 50.0-75.6 Gy. Bleeding must have been refractory to other therapies. Patients received 100% oxygen at 2.0 atmospheres absolute pressure for 90-120 min per treatment in a monoplace chamber. Symptoms were retrospectively scored according to the Late Effects of Normal Tissues-Subjective, Objective, Management, Analytic (LENT-SOMA) scale to evaluate short-term efficacy. Recurrence of hematuria/hematochezia was used to assess long-term efficacy. Results: Four of the 19 patients were lost to follow-up. Fifteen patients were evaluated and received a mean of 29.8 dives: 11 developed HC and 4 proctitis. All patients experienced a reduction in their LENT-SOMA score. After completion of HBOT, the mean LENT-SOMA score was reduced from 0.78 to 0.20 in patients with HC and from 0.66 to 0.26 in patients with proctitis. Median follow-up was 39 months (range, 7-70 months). No cases of hematuria were refractory to HBOT. Complete resolution of hematuria was seen in 81% (n = 9) and partial response in 18% (n = 2). Recurrence of hematuria occurred in 36% (n = 4) after a median of 10 months. Complete resolution of hematochezia was seen in 50% (n = 2), partial response in 25% (n = 1), and refractory bleeding in 25% (n = 1). Conclusions: Hyperbaric oxygen therapy is appropriate for radiation-induced HC once less time-consuming therapies have failed to resolve the bleeding. In these conditions, HBOT is efficacious in the short and long term, with minimal side effects.

  7. 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....

  8. Investigation of Radiation Protection Methodologies for Radiation Therapy Shielding Using Monte Carlo Simulation and Measurement

    Science.gov (United States)

    Tanny, Sean

    The advent of high-energy linear accelerators for dedicated medical use in the 1950's by Henry Kaplan and the Stanford University physics department began a revolution in radiation oncology. Today, linear accelerators are the standard of care for modern radiation therapy and can generate high-energy beams that can produce tens of Gy per minute at isocenter. This creates a need for a large amount of shielding material to properly protect members of the public and hospital staff. Standardized vault designs and guidance on shielding properties of various materials are provided by the National Council on Radiation Protection (NCRP) Report 151. However, physicists are seeking ways to minimize the footprint and volume of shielding material needed which leads to the use of non-standard vault configurations and less-studied materials, such as high-density concrete. The University of Toledo Dana Cancer Center has utilized both of these methods to minimize the cost and spatial footprint of the requisite radiation shielding. To ensure a safe work environment, computer simulations were performed to verify the attenuation properties and shielding workloads produced by a variety of situations where standard recommendations and guidance documents were insufficient. This project studies two areas of concern that are not addressed by NCRP 151, the radiation shielding workload for the vault door with a non-standard design, and the attenuation properties of high-density concrete for both photon and neutron radiation. Simulations have been performed using a Monte-Carlo code produced by the Los Alamos National Lab (LANL), Monte Carlo Neutrons, Photons 5 (MCNP5). Measurements have been performed using a shielding test port designed into the maze of the Varian Edge treatment vault.

  9. Results of conservative surgery and radiation therapy for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Osteen, R.T.; Smith, B.L. (Harvard Medical School, Boston, MA (USA))

    1990-10-01

    For stage I or II breast cancer, conservative surgery and radiation therapy are as effective as modified radical or radical mastectomy. In most cases, cosmetic considerations and the availability of therapy are the primary concerns. The extent of a surgical resection less than a mastectomy has not been a subject of a randomized trial and is controversial. It appears that removal of a quadrant of the breast for small lesions is safe but excessive. It may be possible to limit the breast resection to gross tumor removal for most patients while using wider resections for patients with an extensive intraductal component or for invasive lobular carcinoma. It also appears that excluding patients from breast conservation on the basis of positive margins on the first attempt at tumor excision may be unnecessarily restrictive. Although patients with an extensive intraductal component or invasive lobular carcinoma should have negative margins, it appears that a patient with predominantly invasive ductal carcinoma can be treated without re-excision if all gross tumor has been resected and there is no reason to suspect extensive microscopic disease. Patients with indeterminate margins should have a re-excision. Axillary dissection provides prognostic information and prevents progression of the disease within the axilla. Axillary dissections limited to level I will accurately identify a substantial number of patients who have pathologically positive but clinically negative nodes. When combined with radiation therapy to the axilla, a level I dissection results in a limited number of patients with progressive axillary disease. Patients with pathologically positive axillas and patients at particularly high risk for systemic disease because of the extent of axillary node involvement can be identified by dissections of levels I and II. 60 references.

  10. Estimating the excess lifetime risk of radiation induced secondary malignancy (SMN) in pediatric patients treated with craniospinal irradiation (CSI): Conventional radiation therapy versus helical intensity modulated radiation therapy.

    Science.gov (United States)

    Holmes, Jordan A; Chera, Bhishamjit S; Brenner, David J; Shuryak, Igor; Wilson, Adam K; Lehman-Davis, Misty; Fried, David V; Somasundaram, Vivek; Lian, Jun; Cullip, Tim; Marks, Lawrence B

    To quantify the risk of radiation-induced second malignancies (SMN) in pediatric patients receiving craniospinal irradiation (CSI) either with 3-dimensional conformal radiation therapy (Conv CSI) or tomotherapy helical intensity modulated radiation therapy (Tomo CSI). A novel predictive model that accounts for short- and long-term carcinogenesis was incorporated into our institutional treatment planning system to quantify the lifetime risk of SMN in incidentally irradiated organs. Five pediatric patients previously treated with CSI were studied. For each case, Conv CSI and Tomo CSI plans were computed. The excess absolute number of SMN was computed for each plan for each patient. For female patients, age was varied to assess its impact. Tomo CSI has a much higher risk than Conv CSI for breast cancer. Tomo has a slightly increased risk for the lung, and conventional has a slightly higher risk for the thyroid. Both techniques have intermediate risks to the pancreas and stomach, and lesser risks to the bladder and rectum. For the breast, the magnitude of the absolute risks varied with age: 14.2% versus 7.4% (Tomo vs Conv) age 5; 16.9% versus 7.6% age 10, and 18.6% versus 8.0% age 15. Tomo has a higher risk for inducing breast and lung second cancers, and when using Tomo-based intensity modulated radiation therapy, care should be taken to avoid incidental radiation to the breast. When planning CSI, one needs to balance these cancer risks against other normal tissue effects. Copyright © 2016. Published by Elsevier Inc.

  11. Radiation recall dermatitis triggered by sorafenib after radiation therapy for hepatocellular carcinoma

    Science.gov (United States)

    Kim, Gwi Eon; Song, Hee-Sung; Ahn, Ki Jung; Kim, Young Suk

    2017-01-01

    Sorafenib is widely used for unresectable and metastatic hepatocellular carcinomas. Radiation recall dermatitis (RRD) is an acute inflammatory reaction confined to previously irradiated skin that occurs after the administration of certain drugs. RRD after sorafenib treatment is rare; five cases have been reported thus far. We describe a 44-year-old man irradiated for chest wall bone metastasis from hepatocellular carcinoma. Eight days after radiotherapy completion, systemic therapy for metastatic hepatocellular carcinoma was initiated with sorafenib treatment. Eleven days after starting sorafenib, the patient complained of erythematous rash with pruritus in the chest wall, in a location consistent with the previous radiation field. Sorafenib was continued at the same dose, despite the RRD. The skin reaction subsided over the next 2 weeks without any medical intervention. PMID:29037022

  12. Radiation recall dermatitis triggered by sorafenib after radiation therapy for hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gwi Eon; Song, Hee Sung; Kim, Young Suk [Jeju National University Hospital, Jeju National University School of Medicine, Jeju (Korea, Republic of); Ahn, Ki Jung [Dept. of Radiation Oncology, Inje University Busan Paik Hospital, Inje University of Medicine, Busan (Korea, Republic of)

    2017-09-15

    Sorafenib is widely used for unresectable and metastatic hepatocellular carcinomas. Radiation recall dermatitis (RRD) is an acute inflammatory reaction confined to previously irradiated skin that occurs after the administration of certain drugs. RRD after sorafenib treatment is rare; five cases have been reported thus far. We describe a 44-year-old man irradiated for chest wall bone metastasis from hepatocellular carcinoma. Eight days after radiotherapy completion, systemic therapy for metastatic hepatocellular carcinoma was initiated with sorafenib treatment. Eleven days after starting sorafenib, the patient complained of erythematous rash with pruritus in the chest wall, in a location consistent with the previous radiation field. Sorafenib was continued at the same dose, despite the RRD. The skin reaction subsided over the next 2 weeks without any medical intervention.

  13. A case of post-radiation constrictive pericarditis developing 12 years after radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sakuraba, Motoki; Tanaka, Jun-ichi; Ikeda, Shingo; Kigawa, Ikutaro; Fukuda, Sachito; Wanibuchi, Yasuhiko [Mitsui Memorial Hospital, Tokyo (Japan)

    1997-11-01

    A 70-year-old woman underwent radical mastectomy for carcinoma of the left breast in 1982. Postoperative radiation therapy was given in a total dose of 50 Gy for parasternal and left subclavian nodes. Symptoms of heart failure such as exertional dyspnea, facial edema, and hepatomegaly manifested in 1992. Cardiac catheterization revealed marked elevation of mean right atrial pressure and right ventricular end-diastolic pressure. The pressure wave form of the right ventricle showed the so called ``dip and plateau`` feature. Pericardiectomy without using extracorporeal circulation was performed in 1994. Operative findings and pathological study results were compatible with radiation-induced constrictive pericarditis. She rapidly recovered from heart failure after this operation, and has done very well to date. (author)

  14. [Benchmark experiment to verify radiation transport calculations for dosimetry in radiation therapy].

    Science.gov (United States)

    Renner, Franziska

    2016-09-01

    Monte Carlo simulations are regarded as the most accurate method of solving complex problems in the field of dosimetry and radiation transport. In (external) radiation therapy they are increasingly used for the calculation of dose distributions during treatment planning. In comparison to other algorithms for the calculation of dose distributions, Monte Carlo methods have the capability of improving the accuracy of dose calculations - especially under complex circumstances (e.g. consideration of inhomogeneities). However, there is a lack of knowledge of how accurate the results of Monte Carlo calculations are on an absolute basis. A practical verification of the calculations can be performed by direct comparison with the results of a benchmark experiment. This work presents such a benchmark experiment and compares its results (with detailed consideration of measurement uncertainty) with the results of Monte Carlo calculations using the well-established Monte Carlo code EGSnrc. The experiment was designed to have parallels to external beam radiation therapy with respect to the type and energy of the radiation, the materials used and the kind of dose measurement. Because the properties of the beam have to be well known in order to compare the results of the experiment and the simulation on an absolute basis, the benchmark experiment was performed using the research electron accelerator of the Physikalisch-Technische Bundesanstalt (PTB), whose beam was accurately characterized in advance. The benchmark experiment and the corresponding Monte Carlo simulations were carried out for two different types of ionization chambers and the results were compared. Considering the uncertainty, which is about 0.7 % for the experimental values and about 1.0 % for the Monte Carlo simulation, the results of the simulation and the experiment coincide. Copyright © 2015. Published by Elsevier GmbH.

  15. An analysis of the incidence and related factors for radiation dermatitis in breast cancer patients who receive radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sun Young; Kwon, Hyoung Cheol; Kim, Jung Soo [Dept. of Radiation Oncology, Chonbuk National University Hospital, Jeonju (Korea, Republic of); Lee, Heui Kwan [Prebyterian Medical Center, Jeonju (Korea, Republic of)

    2010-11-15

    We analyzed the incidence and related factors of radiation dermatitis; at first, to recognize whether a decrease in radiation dermatitis is possible or not in breast cancer patients who received radiation therapy. Of 338 patients, 284 with invasive breast cancer who received breast conservation surgery with radiotherapy at Chonbuk National University Hospital from January 2007 to June 2009 were evaluated. Patients who also underwent bolus, previous contralateral breast irradiation and irradiation on both breasts were excluded. For patients who appeared to have greater than moderate radiation dermatitis, the incidence and relating factors for radiation dermatitis were analyzed retrospectively. A total of 207 and 77 patients appeared to have RTOG grade 0/1 or above RTOG grade 2 radiation dermatitis, respectively. The factors found to be statistically significant for the 77 patients who appeared to have greater than moderate radiation dermatitis include the presence of lymphocele due to the stasis of lymph and lymph edema which affect the healing disturbance of radiation dermatitis (p=0.003, p=0.001). Moreover, an allergic reaction to plaster due to the immune cells of skin and the activation of cytokine and concomitant hormonal therapy were also statistically significant factors (p=0.001, p=0.025). Most of the breast cancer patients who received radiation therapy appeared to have a greater than mild case of radiation dermatitis. Lymphocele, lymphedema, an allergy to plaster and concomitant hormonal therapy which affect radiation dermatitis were found to be significant factors. Consequently, we should eliminate lymphocele prior to radiation treatment for patients who appear to have an allergic reaction to plaster. We should also instruct patients of methods to maintain skin moisture if they appear to have a greater than moderate case of radiation dermatitis.

  16. Radiation Hardness of dSiPM Sensors in a Proton Therapy Radiation Environment

    Science.gov (United States)

    Diblen, Faruk; Buitenhuis, Tom; Solf, Torsten; Rodrigues, Pedro; van der Graaf, Emiel; van Goethem, Marc-Jan; Brandenburg, Sytze; Dendooven, Peter

    2017-07-01

    In vivo verification of dose delivery in proton therapy by means of positron emission tomography (PET) or prompt gamma imaging is mostly based on fast scintillation detectors. The digital silicon photomultiplier (dSiPM) allows excellent scintillation detector timing properties and is thus being considered for such verification methods. We present here the results of the first investigation of radiation damage to dSiPM sensors in a proton therapy radiation environment. Radiation hardness experiments were performed at the AGOR cyclotron facility at the KVI-Center for Advanced Radiation Technology, University of Groningen. A 150-MeV proton beam was fully stopped in a water target. In the first experiment, bare dSiPM sensors were placed at 25 cm from the Bragg peak, perpendicular to the beam direction, a geometry typical for an in situ implementation of a PET or prompt gamma imaging device. In the second experiment, dSiPM-based PET detectors containing lutetium yttrium orthosilicate scintillator crystal arrays were placed at 2 and 4 m from the Bragg peak, perpendicular to the beam direction; resembling an in-room PET implementation. Furthermore, the experimental setup was simulated with a Geant4-based Monte Carlo code in order to determine the angular and energy distributions of the neutrons and to determine the 1-MeV equivalent neutron fluences delivered to the dSiPM sensors. A noticeable increase in dark count rate (DCR) after an irradiation with about 108 1-MeV equivalent neutrons/cm2 agrees with observations by others for analog SiPMs, indicating that the radiation damage occurs in the single photon avalanche diodes and not in the electronics integrated on the sensor chip. It was found that in the in situ location, the DCR becomes too large for successful operation after the equivalent of a few weeks of use in a proton therapy treatment room (about 5 × 1013 protons). For PET detectors in an in-room setup, detector performance was unchanged even after an

  17. Modern Radiation Therapy for Primary Cutaneous Lymphomas: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group

    Energy Technology Data Exchange (ETDEWEB)

    Specht, Lena, E-mail: lena.specht@regionh.dk [Departments of Oncology and Hematology, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Dabaja, Bouthaina [Division of Radiation Oncology, Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Illidge, Tim [Institute of Cancer Sciences, University of Manchester, Manchester Academic Health Sciences Centre, The Christie National Health Service Foundation Trust, Manchester (United Kingdom); Wilson, Lynn D. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Hoppe, Richard T. [Department of Radiation Oncology, Stanford University, Stanford, California (United States)

    2015-05-01

    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.

  18. 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....

  19. Tangential intensity modulated radiation therapy (IMRT) to the intact breast.

    Science.gov (United States)

    Dean, Jenna; Hansen, Carmen J; Westhuyzen, Justin; Waller, Brett; Turnbull, Kirsty; Wood, Maree; Last, Andrew

    2016-12-01

    Inverse-planned intensity modulated radiation therapy (IP-IMRT) has potential benefits over other techniques for tangential intact breast radiotherapy. Possible benefits include increased homogeneity, faster planning time, less inter-planner variability and lower doses to organs at risk (OAR). We therefore conducted a pilot study of previously treated intact breast patients to compare the current forward-planned 'field-in-field' technique (FP-IMRT) with an IP-IMRT alternative. The IP-IMRT plans of 20 patients were generated from a template created for the planning system. All patients were prescribed adjuvant whole breast radiotherapy using a hypofractionated regimen of 40.05 Gy in 15 fractions over 3 weeks. Plans were assessed based on visual inspection of coverage as well as statistical analysis and compared to the clinically acceptable FP-IMRT plans. Patients were planned retrospectively in Monaco 3.2(®) using a laterality-specific, tangential planning template. Minor adjustments were made as necessary to meet the planning criteria in the protocol. Dose coverage, maximums, homogeneity indices and doses to OAR were recorded. The IP-IMRT plans provided more consistent coverage (38.18 Gy vs. 36.08 Gy of D95; P = 0.005), a comparable though higher average maximum (D2 = 42.52 Gy vs. 42.08 Gy; P = 0.0001), more homogeneous plans (homogeneity index = 0.908 vs. 0.861; P = 0.01) and somewhat lower V20 heart and lung doses (0.11% vs. 0.89% for heart; 5.4% vs. 7.52% for lung) than FP-IMRT (P > 0.05). Clinically acceptable plans have been generated using the IP-IMRT templates in Monaco. Improvements in consistency and quality were seen when compared to the FP-IMRT plans. The template-based process is an efficient method to inversely plan IMRT for breast patients. © 2016 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of

  20. 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.

  1. Comparative study of adaptive radiations with an example using parasitic flatworms (Platyhelminthes): Cercomeria

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, D.R.; McLennan, D.A. (Univ. of Toronto, Ontario (Canada))

    1993-11-01

    Studies of adaptive radiations require robust phylogenies, estimates of species numbers for monophyletic groups within clades, assessments of the adaptive value of putative key innovations, and estimates of the frequency of speciation modes. Four criteria are necessary to identify an adaptive radiation within the parasitic platyhelminths: (1) a group contains significantly more species than its sister group, (2) species richness is apomorphic, (3) apomorphic traits enhance the potential for adaptively driven modes of speciation (sympatric speciation and speciation by peripheral isolation via host switching), and (4) the frequency of adaptively driven speciation modes is high within the group when compared with data from free-living groups. Only the species-rich Monogenea fulfill all four criteria. The Digenea and Eucestoda also are more species rich than their sister groups, their species richness is derived, and they possess unique characters that increase the potential for host switching to occur. However, because there is not enough information to determine whether the frequency of adaptive modes of speciation is high for those groups, we cannot yet assert that their radiations have been adaptive. 102 refs., 3 figs., 1 tab.

  2. Stereotactic Body Radiation Therapy (SBRT) for Unresectable Pancreatic Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Stauder, Michael C.; Miller, Robert C., E-mail: miller.robert@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

    2010-08-09

    Survival in patients with unresectable pancreatic carcinoma is poor. Studies by Mayo Clinic and the Gastrointestinal Tumor Study Group (GITSG) have established combined modality treatment with chemotherapy and radiation as the standard of care. Use of gemcitabine-based chemotherapy alone has also been shown to provide a benefit, but 5‑year overall survival still remains less than 5%. Conventional radiotherapy is traditionally delivered over a six week period and high toxicity is seen with the concomitant use of chemotherapy. In contrast, SBRT can be delivered in 3–5 days and, when used as a component of combined modality therapy with gemcitabine, disruption to the timely delivery of chemotherapy is minimal. Early single-institution reports of SBRT for unresectable pancreatic carcinoma demonstrate excellent local control with acceptable toxicity. Use of SBRT in unresectable pancreatic carcinoma warrants further investigation in order to improve the survival of patients with historically poor outcomes.

  3. Effects of Radiation Therapy on Established Neurogenic Heterotopic Ossification.

    Science.gov (United States)

    Lee, Chan Ho; Shim, Su Jung; Kim, Hyun Jung; Yang, Hyuna; Kang, Youn Joo

    2016-12-01

    Heterotopic ossification (HO) is frequently seen on rehabilitation units after spinal cord injuries, fractures, brain injuries, and limb amputations. Currently, there is no effective treatment for HO other than prophylaxis with anti-inflammatory medications, irradiation, and bisphosphonate administration. These prophylactic treatments are not effective for managing ectopic bone once it has formed. Here we describe three cases of established neurogenic HO treated with radiation therapy (RT). All patients had decreased serum alkaline phosphatase (ALP) and bone-specific ALP levels with decreased pain but increased range of motion immediately after RT. Post-treatment X-rays revealed no further growth of the HO. All patients maintained clinical and laboratory improvements 4 or 6 months after the RT. Our results suggest that RT is safe and effective in decreasing pain and activity of neurogenic HO.

  4. Clinical observation of taste disturbance induced by radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Yuzuru; Sera, Koshi; Nagasawa, Hiroshi; Fukushima, Noriyuki; Yajin, Koji; Harada, Yasuo (Hiroshima Univ. (Japan). School of Medicine)

    1984-02-01

    Qualitative gustometry (filter paper disc method) was performed in six patients who underwent radiation therapy. Following results were obtained. 1) Subjective taste disturbance appeared when irradiation dosage amounted to 1000-2000 rad. Whereas, it disappeared in 1 to 3 months after the termination of irradiation. 2) The longer the period of irradiation, the more slowly taste disturbance recovered. 3) Disgeusia was noticed in 44.3% of S, 66.7% of N, 70% of T and 36.2% of Q tests. 4) Taste thresholds in the apical tongue region improved almost parallel to subjective recovery of the taste. Occasionally taste disturbance was prolonged over a month. This is possibly due to delayed regeneration of the gustatory buds. Furthermore, conditions of the oral cavity, such as infection, or mechanical stimulation, may well influence degree of taste disturbance and the process of regeneration.

  5. Nanoparticles for Radiation Therapy Enhancement: the Key Parameters.

    Science.gov (United States)

    Retif, Paul; Pinel, Sophie; Toussaint, Magali; Frochot, Céline; Chouikrat, Rima; Bastogne, Thierry; Barberi-Heyob, Muriel

    2015-01-01

    This review focuses on the radiosensitization strategies that use high-Z nanoparticles. It does not establish an exhaustive list of the works in this field but rather propose constructive criticisms pointing out critical factors that could improve the nano-radiation therapy. Whereas most reviews show the chemists and/or biologists points of view, the present analysis is also seen through the prism of the medical physicist. In particular, we described and evaluated the influence of X-rays energy spectra using a numerical analysis. We observed a lack of standardization in preclinical studies that could partially explain the low number of translation to clinical applications for this innovative therapeutic strategy. Pointing out the critical parameters of high-Z nanoparticles radiosensitization, this review is expected to contribute to a larger preclinical and clinical development.

  6. Radiation Therapy for Hepatocellular Carcinoma with Portal Vein Tumor Thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seung Gyu; Kim, Jin Hee; Byun, Sang Jun; Kim, Ok Bae; Hwang, Jae Seok; Oh, Young Kee; Choi, Tae Jin [Dongsan Medical Center, Keimyung University School of Medicine, Daegu (Korea, Republic of)

    2011-03-15

    To evaluate the effectiveness of radiation therapy (RT) for hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) and to analyze the prognostic factors. From December 2004 to April 2009, 70 patients who had HCC with PVTT were treated with RT at Keimyung University Dongsan Medical Center. Nineteen patients whose total dose was below 30 Gy and one patient who underwent liver transplantation were excluded. The remaining 50 patients (45 males, 5 females; median age 55 years) were analyzed. According to the LCSGJ TNM stage, there were 27 patients (54.0%) with stage III and 23 (46.0%) with stage IV. Total dose of 30-54 Gy was administered (median 45). Thirty patients (60.0%) were treated with concurrent chemoradiation therapy (CCRT). The median follow-up duration was from 13.5 months (range, 3 to 70 months). The median survival time from the start of RT was 9 months. One-year and 2-year overall survival rates were 24.9% and 11.2%, respectively. At the follow-up time, three patients (6.0%) displayed no evidence of disease. Seven patients (14.0%) were alive with disease, and 40 (80.0%) patients had expired due to disease progression. CCRT was associated with worse survival than RT alone (p=0.034). Response to RT (p=0.037), CLIP stage (p=0.017), and TNM stage (p=0.041) were statistically significant prognostic factors. There was no radiation-induced liver disease. RT is an effective and safe modality for HCC with PVTT. Further studies such as prospective randomized trials are needed to confirm the role of RT for HCC with PVTT.

  7. Proton-minibeam radiation therapy: A proof of concept

    Energy Technology Data Exchange (ETDEWEB)

    Prezado, Y. [IMNC-UMR 8165, CNRS, Paris 7 and Paris 11 Universities, 15 rue Georges Clemenceau, 91406 Orsay Cedex (France); Fois, G. R. [Dipartimento di Fisica, Universita degli Studi di Cagliari, Strada provinciale Monserrato Sestu km 0.700, Monserrato, Cagliari 09042 (Italy)

    2013-03-15

    Purpose: This Monte Carlo simulation work aims at studying a new radiotherapy approach called proton-minibeam radiation therapy (pMBRT). The main objective of this proof of concept was the evaluation of the possible gain in tissue sparing, thanks to the spatial fractionation of the dose, which could be used to deposit higher and potentially curative doses in clinical cases where tissue tolerances are a limit for conventional methods. Methods: Monte Carlo simulations (GATE v.6) have been used as a method to calculate the ratio of the peak-to-valley doses (PVDR) for arrays of proton minibeams of 0.7 mm width and several center-to-center distances, at different depths in a water phantom. The beam penumbras were also evaluated as an important parameter for tissue sparing, for example, in the treatment of non-cancer diseases like epilepsy. Two proton energies were considered in this study: a clinically relevant energy (105 MeV) and a very high energy (1 GeV), to benefit from a reduced lateral scattering. For the latter case, an interlaced geometry was also evaluated. Results: Higher or similar PVDR than the ones obtained in x-rays minibeam radiation therapy were achieved in several pMBRT configurations. In addition, for the two energies studied, the beam penumbras are smaller than in the case of Gamma Knife radiosurgery. Conclusions: The high PVDR obtained for some configurations and the small penumbras in comparison with existing radiosurgery techniques, suggest a potential gain in healthy tissue sparing in this new technique. Biological studies are warranted to assess the effects of pMBRT on both normal and tumoral tissues.

  8. DICOM and imaging informatics-based radiation therapy (RT) server

    Science.gov (United States)

    Law, Maria Y. Y.; Huang, H. K.; Zhang, Xiaoyan; Zhang, Jianguo

    2002-05-01

    Radiation therapy (RT) is an image intensive treatment. It requires images from projection X-rays, CT, MR, PET for tumor localization, treatment planning and verification of treatment plans. It also needs patient information, images and their processing for tumor localization and dose computation to ensure the delivery of uniform high dose to the target but avoidance of sensitive structures. In these processes, PACS and imaging informatics technologies are used extensively. However, they are not integrated with these technologies as a complete radiation treatment system. Currently RT treatment still relies mostly on tedious manual image and data transfer methods because the community as a whole has not championed the concept of system integration heavily. System integration of RT treatment has many benefits including lower equipment and operation costs, streamline treatment procedures, and better healthcare delivery to the patient. In this paper, we discuss the concept of a DICOM and imaging informatics-based RT server as an attempt to integrate diverse healthcare information systems, imaging modalities and RT equipment into one seamless treatment system.

  9. Stroke-like Migraine Attacks after Radiation Therapy Syndrome

    Directory of Open Access Journals (Sweden)

    Qian Zheng

    2015-01-01

    Full Text Available Objective: To summarize the clinical presentation, pathogenesis, neuroimaging, treatment, and outcome of stroke-like migraine attacks after radiation therapy (SMART syndrome, and to propose diagnostic criteria for this disorder. Data Sources: We searched the PubMed database for articles in English published from 1995 to 2015 using the terms of "stroke-like AND migraine AND radiation." Reference lists of the identified articles and reviews were used to retrieve additional articles. Study Selection: Data and articles related to late-onset effects of cerebral radiation were selected and reviewed. Results: SMART is a rare condition that involves complex migraines with focal neurologic deficits following cranial irradiation for central nervous system malignancies. The recovery, which ranges from hours to days to weeks, can be partial or complete. We propose the following diagnostic criteria for SMART: (1 Remote history of therapeutic external beam cranial irradiation for malignancy; (2 prolonged, reversible clinical manifestations mostly years after irradiation, which may include migraine, seizures, hemiparesis, hemisensory deficits, visuospatial defect, aphasia, confusion and so on; (3 reversible, transient, unilateral cortical gadolinium enhancement correlative abnormal T2 and fluid-attenuated inversion recovery signal of the affected cerebral region; (4 eventual complete or partial recovery, the length of duration of recovery ranging from hours to days to weeks; (5 no evidence of residual or recurrent tumor; (6 not attributable to another disease. To date, no specific treatment has been identified for this syndrome. Conclusions: SMART is an extremely rare delayed complication of brain irradiation. However, improvements in cancer survival rates have resulted in a rise in its frequency. Hence, awareness and recognition of the syndrome is important to make a rapid diagnosis and avoid aggressive interventions such as brain biopsy and cerebral

  10. RT-13OPTIMIZING RADIATION THERAPY FOR GLIOBLASTOMA PATIENTS: A COMPARATIVE STUDY OF USING DIFFERENT MRI MODALITIES TO MINIMIZE RADIATION INJURY

    Science.gov (United States)

    Kim, Arin; Lee, Albert Weilin; Lee, Anna; Yanagihara, Theodore; Jani, Ashish; Isaacson, Steven R.; Cheng, Simon K.; Bruce, Jeffrey N.; Sisti, Michael B.; McKhann, Guy M.; Iwamoto, Fabio; Lassman, Andrew; Wang, Tony J.C.

    2014-01-01

    Glioblastoma multiforme is the most common and lethal primary malignant brain tumor and radiation therapy is considered the standard of care in the adjuvant setting. Current radiation treatment planning guidelines recommend FLAIR MRI sequence with a 2 cm margin to encompass the subclinical tumor spread. However, the FLAIR modality extensively visualizes the surrounding edema, possibly leading to unnecessary radiation toxicity to healthy brain tissue. We hypothesize that we can optimize radiation therapy by using alternative MRI modalities or by decreasing clinical tumor volume margins to minimize toxicity without compromising accurate tumor targeting. We retrospectively collected data for 21 patients with pathology confirmed recurrence and created radiation treatment plans using ADC, ADC without FLAIR shine-through (ADCst), DWI, T1, and FLAIR. For the FLAIR both a 1 cm and 2 cm margin was used (FLAIR1 and FLAIR2). Boolean operators were used to calculate the accuracy of targeting tumor recurrence and excessive radiation volume compared to the standard FLAIR2 treatment plan. All MRI modalities had complete coverage of the recurrent tumor and the mean differences in accuracy between the different MRI modalities and FLAIR2 was not significant. However, there was a significant reduction in the excessive radiation volume compared to FLAIR2. ADCst had a 51.3% reduction, DWI 42.3%, T1 42.6%, and FLAIR1 44.6% reduction of excessive radiation volume compared to FLAIR2 (p < 0.05). ADC did not have a significant reduction of excessive radiation volume compared to FLAIR2. Our data support the hypothesis that using MRI modalities other than the standard FLAIR or decreasing the margin by 1cm may optimize radiation therapy for GBM patients by reducing unnecessary radiation dose to healthy brain tissue without compromising accuracy. By using new MRI modalities in radiation treatment planning or modifying clinical tumor volume margins we can decrease radiation toxicity to patients

  11. ESTRO consensus guideline on target volume delineation for elective radiation therapy of early stage breast cancer.

    Science.gov (United States)

    Offersen, Birgitte V; Boersma, Liesbeth J; Kirkove, Carine; Hol, Sandra; Aznar, Marianne C; Biete Sola, Albert; Kirova, Youlia M; Pignol, Jean-Philippe; Remouchamps, Vincent; Verhoeven, Karolien; Weltens, Caroline; Arenas, Meritxell; Gabrys, Dorota; Kopek, Neil; Krause, Mechthild; Lundstedt, Dan; Marinko, Tanja; Montero, Angel; Yarnold, John; Poortmans, Philip

    2015-01-01

    Delineation of clinical target volumes (CTVs) is a weak link in radiation therapy (RT), and large inter-observer variation is seen in breast cancer patients. Several guidelines have been proposed, but most result in larger CTVs than based on conventional simulator-based RT. The aim was to develop a delineation guideline obtained by consensus between a broad European group of radiation oncologists. During ESTRO teaching courses on breast cancer, teachers sought consensus on delineation of CTV through dialogue based on cases. One teacher delineated CTV on CT scans of 2 patients, followed by discussion and adaptation of the delineation. The consensus established between teachers was sent to other teams working in the same field, both locally and on a national level, for their input. This was followed by developing a broad consensus based on discussions. Borders of the CTV encompassing a 5mm margin around the large veins, running through the regional lymph node levels were agreed, and for the breast/thoracic wall other vessels were pointed out to guide delineation, with comments on margins for patients with advanced breast cancer. The ESTRO consensus on CTV for elective RT of breast cancer, endorsed by a broad base of the radiation oncology community, is presented to improve consistency. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. Dynamics of competing species in a model of adaptive radiation and macroevolution

    Science.gov (United States)

    de Blasio, Birgitte Freiesleben; de Blasio, Fabio Vittorio

    2005-09-01

    We present a simple model of adaptive radiation in evolution based on species competition. Competition is found to promote species divergence and branching, and to dampen the net species production. In the model simulations, high taxonomic diversification and branching take place during the beginning of the radiation. The results show striking similarities with empirical data and highlight the mechanism of competition as an important driving factor for accelerated evolutionary transformation.

  13. Prevention of normal tissue complications in radiation therapy of head and neck cancer : the role of 3D conformal radiation therapy (3DCRT)

    NARCIS (Netherlands)

    O.B. Wijers (Oda)

    2002-01-01

    textabstractIn The Netherlands. head and neck cancer (3.9%) ranks the eighth most frequemly diagnoscd malignant tumor. Radiation therapy (IIT) plays an important role in the treatmem of patients with head and neck cancer, as they constitute approximately 6% of those treated in a routine radiation

  14. 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.

  15. Cranial shape evolution in adaptive radiations of birds: comparative morphometrics of Darwin's finches and Hawaiian honeycreepers.

    Science.gov (United States)

    Tokita, Masayoshi; Yano, Wataru; James, Helen F; Abzhanov, Arhat

    2017-02-05

    Adaptive radiation is the rapid evolution of morphologically and ecologically diverse species from a single ancestor. The two classic examples of adaptive radiation are Darwin's finches and the Hawaiian honeycreepers, which evolved remarkable levels of adaptive cranial morphological variation. To gain new insights into the nature of their diversification, we performed comparative three-dimensional geometric morphometric analyses based on X-ray microcomputed tomography (µCT) scanning of dried cranial skeletons. We show that cranial shapes in both Hawaiian honeycreepers and Coerebinae (Darwin's finches and their close relatives) are much more diverse than in their respective outgroups, but Hawaiian honeycreepers as a group display the highest diversity and disparity of all other bird groups studied. We also report a significant contribution of allometry to skull shape variation, and distinct patterns of evolutionary change in skull morphology in the two lineages of songbirds that underwent adaptive radiation on oceanic islands. These findings help to better understand the nature of adaptive radiations in general and provide a foundation for future investigations on the developmental and molecular mechanisms underlying diversification of these morphologically distinguished groups of birds.This article is part of the themed issue 'Evo-devo in the genomics era, and the origins of morphological diversity'. © 2016 The Authors.

  16. Reducing rectal injury in men receiving prostate cancer radiation therapy: current perspectives

    Directory of Open Access Journals (Sweden)

    Serrano NA

    2017-07-01

    Full Text Available Nicholas A Serrano,1 Noah S Kalman,1 Mitchell S Anscher2 1Department of Radiation Oncology, Virginia Commonwealth University – Massey Cancer Center, Richmond, VA, 2Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX, USA Abstract: Dose escalation is now the standard of care for the treatment of prostate cancer with radiation therapy. However, the rectum tends to be the dose-limiting structure when treating prostate cancer, given its close proximity. Early and late toxicities can occur when the rectum receives large doses of radiation therapy. New technologies allow for prevention of these toxicities. In this review, we examine the evidence that supports various dose constraints employed to prevent these rectal injuries from occurring. We also examine the use of intensity-modulated radiation therapy and how this compares to older radiation therapy techniques that allow for further sparing of the rectum during a radiation therapy course. We then review the literature on endorectal balloons and the effects of their daily use throughout a radiation therapy course. Tissue spacers are now being investigated in greater detail; these devices are injected into the rectoprostatic fascia to physically increase the distance between the prostate and the anterior rectal wall. Last, we review the use of systemic drugs, specifically statin medications and antihypertensives, as well as their impact on rectal toxicity. Keywords: rectal toxicity, radiation therapy, prostate, prevention 

  17. Molecular targeted treatment and radiation therapy for rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Marquardt, Friederike; Roedel, Franz; Capalbo, Gianni; Weiss, Christian; Roedel, Claus [Dept. of Radiation Therapy, Univ. of Frankfurt/Main (Germany)

    2009-06-15

    Background: EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols. Material and methods: cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings. Results: the combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low rates of pathologic complete remission have been noted in several phase II studies. The K-ras mutation status and the gene copy number of EGFR may predict tumor response. The toxicity pattern (radiation-induced enteritis, perforations) and surgical complications (wound healing, fistula, bleeding) observed in at least some of the clinical studies with bevacizumab and CRT warrant further investigations. Conclusion: longer follow-up (and, finally, randomized trials) is needed to draw any firm conclusions with respect to local and distant failure rates, and toxicity associated with these novel treatment approaches. (orig.)

  18. Intraoperative radiation therapy (IORT) for adenocarcinoma of the pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Yasue, Mitsunori

    1988-04-01

    Between April 1980 and August 1987, a total of 54 patients with pancreatic adenocarcinoma were treated with intraoperative radiation therapy (IORT). Thirty-five patients underwent IORT with palliative intent (Group I), and the remaining 19 underwent it as an adjuvant therapy for pancreatectomy (Group II). The dosage of electron beams ranged from 12 to 30 Gy in Group I and from 20 to 30 Gy in Group II. Intractable back pain that was observed in 25 patients was relieved in 20 patients (80 %) within one week after IORT. The median survival was 5.3 months in Group I and 9.4 months in Group II. The longest survival (6 years and 10 months) was attained in a patient undergoing absolute non-curative distal pancreatectomy, followed by 20 Gy of IORT. In comparing patients treated before and after the introduction of IORT, both survival rate and staying-home survival rate were significantly better in the era of IORT during which background factors were rather worse. (Namekawa, K.).

  19. Cancer stem cells, cancer cell plasticity and radiation therapy.

    Science.gov (United States)

    Vlashi, Erina; Pajonk, Frank

    2015-04-01

    Since the first prospective identification of cancer stem cells in solid cancers the cancer stem cell hypothesis has reemerged as a research topic of increasing interest. It postulates that solid cancers are organized hierarchically with a small number of cancer stem cells driving tumor growth, repopulation after injury and metastasis. They give rise to differentiated progeny, which lack these features. The model predicts that for any therapy to provide cure, all cancer stem cells have to be eliminated while the survival of differentiated progeny is less critical. In this review we discuss recent reports challenging the idea of a unidirectional differentiation of cancer cells. These reports provide evidence supporting the idea that non-stem cancer cells exhibit a remarkable degree of plasticity that allows them to re-acquire cancer stem cell traits, especially in the context of radiation therapy. We summarize conditions under which differentiation is reversed and discuss the current knowledge of the underlying mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. The Role of Hypofractionated Radiation Therapy with Photons, Protons and Heavy Ions for Treating Extracranial Lesions

    Directory of Open Access Journals (Sweden)

    Aaron Michael Laine

    2016-01-01

    Full Text Available Traditionally, the ability to deliver large doses of ionizing radiation to a tumor has been limited by radiation induced toxicity to normal surrounding tissues. This was the initial impetus for the development of conventionally fractionated radiation therapy, where large volumes of healthy tissue received radiation and were allowed the time to repair the radiation damage. However, advances in radiation delivery techniques and image guidance have allowed for more ablative doses of radiation to be delivered in a very accurate, conformal and safe manner with shortened fractionation schemes. Hypofractionated regimens with photons have already transformed how certain tumor types are treated with radiation therapy. Additionally, hypofractionation is able to deliver a complete course of ablative radiation therapy over a shorter period of time compared to conventional fractionation regimens making treatment more convenient to the patient and potentially more cost-effective. Recently there has been an increased interest in proton therapy because of the potential further improvement in dose distributions achievable due to their unique physical characteristics. Furthermore, with heavier ions the dose conformality is increased and in addition there is potentially a higher biological effectiveness compared to protons and photons. Due to the properties mentioned above, charged particle therapy has already become an attractive modality to further investigate the role of hypofractionation in the treatment of various tumors. This review will discuss the rationale and evolution of hypofractionated radiation therapy, the reported clinical success with initially photon and then charged particle modalities, and further potential implementation into treatment regimens going forward.

  1. Dysuria Following Stereotactic Body Radiation Therapy for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Einsley-Marie eJanowski

    2015-07-01

    Full Text Available Background: Dysuria following prostate radiation therapy is a common toxicity that adversely affects patients’ quality of life and may be difficult to manage. Methods: 204 patients treated with stereotactic body radiation therapy (SBRT from 2007 to 2010 for localized prostate carcinoma with a minimum follow up of three years were included in this retrospective review of prospectively collected data. All patients were treated to 35-36.25Gy in 5 fractions delivered with robotic SBRT with real time fiducial tracking. Dysuria and other lower urinary tract symptoms were assessed via Question 4b (Pain or burning on urination of the Expanded Prostate Index Composite (EPIC-26 and the American Urological Association (AUA Symptom Score at baseline and at routine follow up. Results: 204 patients (82 low-, 105 intermediate-, and 17 high risk according to the D’Amico classification at a median age of 69 years (range 48-91 received SBRT for their localized prostate cancer with a median follow up of 47 months. Bother associated with dysuria significantly increased from a baseline of 12% to a maximum of 43% at one month (p<0.0001. There were two distinct peaks of moderate to severe dysuria bother at 1 month and at 6-12 months, with 9% of patients experiencing a late transient dysuria flare. While a low level of dysuria was seen through the first two years of follow-up, it returned to below baseline by two years (p=0.91. The median baseline AUA score of 7.5 significantly increased to 11 at 1 month (p<0.0001 and returned to 7 at 3 months (p= 0.54. Patients with dysuria had a statistically higher AUA score at baseline and at all follow-ups up to 30 months. Dysuria significantly correlated with dose and AUA score on multivariate analysis. Frequency and strain significantly correlated with dysuria on stepwise multivariate analysis.Conclusions: The rate and severity of dysuria following SBRT is comparable to patients treated with other radiation modalities.

  2. First reported treatment of aggressive hemangioma with intraoperative radiation therapy and kyphoplasty (Kypho-IORT

    Directory of Open Access Journals (Sweden)

    B. Pinar Sedeño

    2017-02-01

    Full Text Available Aggressive hemangiomas invade the spinal canal and/or paravertebral space and may cause cord compression and neurological symptoms. Radiation therapy was recognized as an effective strategy for the treatment of aggressive hemangiomas. Here, it is reported the first case of aggressive vertebral hemangioma treated by a combination of intraoperative radiation therapy and kyphoplasty (Kypho-IORT.

  3. 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 ...

  4. Hierarchical Adaptive Solution of Radiation Transport Problems on Unstructured Grids

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Cassiano R. E de Oliveira

    2008-06-30

    Computational radiation transport has steadily gained acceptance in the last decade as a viable modeling tool due to the rapid advancements in computer software and hardware technologies. It can be applied for the analysis of a wide range of problems which arise in nuclear reactor physics, medical physics, atmospheric physics, astrophysics and other areas of engineering physics. However, radiation transport is an extremely chanllenging computational problem since the governing equation is seven-deimensional (3 in space, 2 in direction, 1 in energy, and 1 in time) with a high degree of coupleing betwen these variables. If not careful, this relatively large number of independent variables when discretized can potentially lead to sets of linear equations of intractable size. Though parallel computing has allowed the solution of very large problems, avaliable computational resources will always be finite due to the fact that every more sophisticated multiphysics models are being demanded by industry. There is thus the pressing requirement to optimize the discretizations so as to minimize the effort and maximize the accuracy.

  5. SU-C-16A-06: Optimum Radiation Source for Radiation Therapy of Skin Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Safigholi, Habib [Science and Research Branch, Islamic Azad University, Fars, Persepolis (Iran, Islamic Republic of); Meigooni, A S. [Comprehensive cancer center of Nevada, Las Vegas, NV (United States); University of Nevada Las Vegas (UNLV), Las Vegas, NV (United States)

    2014-06-15

    Purpose: Recently, different applicators are designed for treatment of the skin cancer such as scalp and legs, using Ir-192 HDR Brachytherapy Sources (IR-HDRS), Miniature Electronic Brachytherapy Sources (MEBXS), and External Electron Beam Radiation Therapy (EEBRT). Although, all of these methodologies may deliver the desired radiation dose to the skin, the dose to the underlying bone may become the limiting factor for selection of the optimum treatment technique. In this project the radiation dose delivered to the underlying bone has been evaluated as a function of the radiation source and thickness of the underlying bone. Methods: MC simulations were performed using MCNP5 code. In these simulations, the mono-energetic and non-divergent photon beams of 30 keV, 50 keV, and 70 keV for MEBXS, 380 keV photons for IR-HDRS, and 6 MeV mono-energetic electron beam for EEBRT were modeled. A 0.5 cm thick soft tissue (0.3 cm skin and 0.2 cm adipose) with underlying 0.5 cm cortical bone followed by 14 cm soft tissue are utilized for simulations. Results: Dose values to bone tissue as a function of beam energy and beam type, for a delivery of 5000 cGy dose to skin, were compared. These results indicate that for delivery of 5000 cGy dose to the skin surface with 30 keV, 50 keV, 70 keV of MEBXS, IR-HDRS, and EEBRT techniques, bone will receive 31750 cGy, 27450 cGy, 18550 cGy, 4875 cGy, and 10450 cGy, respectively. Conclusion: The results of these investigations indicate that, for delivery of the same skin dose, average doses received by the underlying bone are 5.2 and 2.2 times larger with a 50 keV MEBXS and EEBRT techniques than IR-HDRS, respectively.

  6. Quality of Intensity Modulated Radiation Therapy Treatment Plans Using a {sup 60}Co Magnetic Resonance Image Guidance Radiation Therapy System

    Energy Technology Data Exchange (ETDEWEB)

    Wooten, H. Omar, E-mail: hwooten@radonc.wustl.edu; 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

    Purpose: This work describes a commercial treatment planning system, its technical features, and its capabilities for creating {sup 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 {sup 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 {sup 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 {sup 60}Co IMRT plans achieved PTV coverage and OAR sparing that were similar to linac plans. PTV conformity for {sup 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 {sup 60}Co plan OARs were within clinical tolerances. Conclusions: A commercial {sup 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.

  7. Mometasone Furoate Cream Reduces Acute Radiation Dermatitis in Patients Receiving Breast Radiation Therapy: Results of a Randomized Trial

    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.

  8. Applications of Cherenkov Light Emission for Dosimetry in Radiation Therapy

    Science.gov (United States)

    Glaser, Adam Kenneth

    Since its discovery in the 1930's, the Cherenkov effect has been paramount in the development of high-energy physics research. It results in light emission from charged particles traveling faster than the local speed of light in a dielectric medium. The ability of this emitted light to describe a charged particle's trajectory, energy, velocity, and mass has allowed scientists to study subatomic particles, detect neutrinos, and explore the properties of interstellar matter. However, only recently has the phenomenon been considered in the practical context of medical physics and radiation therapy dosimetry, where Cherenkov light is induced by clinical x-ray photon, electron, and proton beams. To investigate the relationship between this phenomenon and dose deposition, a Monte Carlo plug-in was developed within the Geant4 architecture for medically-oriented simulations (GAMOS) to simulate radiation-induced optical emission in biological media. Using this simulation framework, it was determined that Cherenkov light emission may be well suited for radiation dosimetry of clinically used x-ray photon beams. To advance this application, several novel techniques were implemented to realize the maximum potential of the signal, such as time-gating for maximizing the signal to noise ratio (SNR) and Cherenkov-excited fluorescence for generating isotropic light release in water. Proof of concept experiments were conducted in water tanks to demonstrate the feasibility of the proposed method for two-dimensional (2D) projection imaging, three-dimensional (3D) parallel beam tomography, large field of view 3D cone beam tomography, and video-rate dynamic imaging of treatment plans for a number of common radiotherapy applications. The proposed dosimetry method was found to have a number of unique advantages, including but not limited to its non-invasive nature, water-equivalence, speed, high-resolution, ability to provide full 3D data, and potential to yield data in-vivo. Based on

  9. A case of spontaneous pneumothorax following radiation therapy for non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Himanshu Bhardwaj

    2013-01-01

    Full Text Available Spontaneous pneumothorax (SPTX is a potentially devastating rare complication of the thoracic radiation therapy. Most of the cases in the medical literature, have been described in lymphoma patients receiving radiation therapy. The pathogenesis of this adverse event remains undefined although different mechanisms have been proposed. We present a case of post-radiation therapy SPTX in a non-small cell lung cancer (NSCLC, following intensity modulated radiation therapy (IMRT, which to our knowledge is the first such reported case related to this newer mode of radiation therapy. This report highlights the importance of keeping a close eye for this complication as timely treatment with chest tube insertion and drainage of the pneumothorax can be a lifesaving in these patients.

  10. Improving the quality, efficiency and robustness of radiation therapy planning and delivery through mathematical optimization

    NARCIS (Netherlands)

    Balvert, Marleen

    2017-01-01

    Radiation therapy is an established cancer treatment which exploits ionizing radiation to harm tumourous cells. As radiation can pass through healthy tissue to reach the tumour, this treatment is particularly useful in the case of deep-seated tumours. However, it inevitably yields exposure of the

  11. Role of radiation therapy in the treatment of benign ocular diseases

    Directory of Open Access Journals (Sweden)

    Racheline

    1991-01-01

    Full Text Available Radiation therapy, although a prime treatment modality for malignant disease, has few definitive indications for some benign ocular diseases too. Orbital pseudotumour, Graves ophthalmopathy and pterygium are the conditions where the radiation oncologist has got an important role to play. This article reviews the current status of the role of radiation and its effectiveness in the management of these diseases.

  12. 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.

  13. Comparison of acute and subacute genitourinary and gastrointestinal adverse events of radiotherapy for prostate cancer using intensity-modulated radiation therapy, three-dimensional conformal radiation therapy, permanent implant brachytherapy and high-dose-rate brachytherapy

    NARCIS (Netherlands)

    Morimoto, Masahiro; Yoshioka, Yasuo; Konishi, Koji; Isohashi, Fumiaki; Takahashi, Yutaka; Ogata, Toshiyuki; Koizumi, Masahiko; Teshima, Teruki; Bijl, Henk P; van der Schaaf, Arjen; Langendijk, Johannes A; Ogawa, Kazuhiko

    2014-01-01

    AIMS AND BACKGROUND: To examine acute and subacute urinary and rectal toxicity in patients with localized prostate cancer monotherapeutically treated with the following four radiotherapeutic techniques: intensity-modulated radiation therapy, three-dimensional conformal radiation therapy,

  14. CRASH: A Block-Adaptive-Mesh Code for Radiative Shock Hydrodynamics

    Science.gov (United States)

    van der Holst, B.; Toth, G.; Sokolov, I. V.; Powell, K. G.; Holloway, J. P.; Myra, E. S.; Stout, Q.; Adams, M. L.; Morel, J. E.; Drake, R. P.

    2011-01-01

    We describe the CRASH (Center for Radiative Shock Hydrodynamics) code, a block adaptive mesh code for multi-material radiation hydrodynamics. The implementation solves the radiation diffusion model with the gray or multigroup method and uses a flux limited diffusion approximation to recover the free-streaming limit. The electrons and ions are allowed to have different temperatures and we include a flux limited electron heat conduction. The radiation hydrodynamic equations are solved in the Eulerian frame by means of a conservative finite volume discretization in either one, two, or three-dimensional slab geometry or in two-dimensional cylindrical symmetry. An operator split method is used to solve these equations in three substeps: (1) solve the hydrodynamic equations with shock-capturing schemes, (2) a linear advection of the radiation in frequency-logarithm space, and (3) an implicit solve of the stiff radiation diffusion, heat conduction, and energy exchange. We present a suite of verification test problems to demonstrate the accuracy and performance of the algorithms. The CRASH code is an extension of the Block-Adaptive Tree Solarwind Roe Upwind Scheme (BATS-R-US) code with this new radiation transfer and heat conduction library and equation-of-state and multigroup opacity solvers. Both CRASH and BATS-R-US are part of the publicly available Space Weather Modeling Framework (SWMF).

  15. CRASH: A Block-adaptive-mesh Code for Radiative Shock Hydrodynamics—Implementation and Verification

    Science.gov (United States)

    van der Holst, B.; Tóth, G.; Sokolov, I. V.; Powell, K. G.; Holloway, J. P.; Myra, E. S.; Stout, Q.; Adams, M. L.; Morel, J. E.; Karni, S.; Fryxell, B.; Drake, R. P.

    2011-06-01

    We describe the Center for Radiative Shock Hydrodynamics (CRASH) code, a block-adaptive-mesh code for multi-material radiation hydrodynamics. The implementation solves the radiation diffusion model with a gray or multi-group method and uses a flux-limited diffusion approximation to recover the free-streaming limit. Electrons and ions are allowed to have different temperatures and we include flux-limited electron heat conduction. The radiation hydrodynamic equations are solved in the Eulerian frame by means of a conservative finite-volume discretization in either one-, two-, or three-dimensional slab geometry or in two-dimensional cylindrical symmetry. An operator-split method is used to solve these equations in three substeps: (1) an explicit step of a shock-capturing hydrodynamic solver; (2) a linear advection of the radiation in frequency-logarithm space; and (3) an implicit solution of the stiff radiation diffusion, heat conduction, and energy exchange. We present a suite of verification test problems to demonstrate the accuracy and performance of the algorithms. The applications are for astrophysics and laboratory astrophysics. The CRASH code is an extension of the Block-Adaptive Tree Solarwind Roe Upwind Scheme (BATS-R-US) code with a new radiation transfer and heat conduction library and equation-of-state and multi-group opacity solvers. Both CRASH and BATS-R-US are part of the publicly available Space Weather Modeling Framework.

  16. Temporal lobe changes following radiation therapy: imaging and proton MR spectroscopic findings

    Energy Technology Data Exchange (ETDEWEB)

    Chong, V.F.H.; Rumpel, H.; Fan, Y.F. [Dept. of Diagnostic Radiology, Singapore General Hospital (Singapore); Mukherji, S.K. [North Carolina Univ., Chapel Hill (United States). Dept. of Radiology

    2001-02-01

    Radiation therapy for nasopharyngeal carcinoma affects the temporal lobes. This paper characterizes proton MR spectroscopic findings of the temporal lobes and correlates them with imaging changes. Single-voxel proton MR spectroscopic examinations were acquired from 13 healthy adult volunteers (25 spectra) and 18 patients (28 spectra). All patients had biopsy-confirmed nasopharyngeal carcinoma and were previously treated with radiation therapy. Six patients (33 %) had a single treatment and12 (67 %) patients had two treatments. Point resolved spectroscopy (PRESS) method was used (TR = 3000 ms, TE = 135 ms) and data processed automatically using the LCModel software package for metabolite quantification. Voxel size and geometry were adapted to the lesion to reduce skull-base lipid contamination. The metabolites were quantitated relative to water signal. For each location, an additional non-water-suppressed reference scan in fully relaxed conditions was performed. The imaging findings were divided into four categories: I, normal; II, edema only; III, contrast-enhancing lesions; and IV, cystic encephalomalacia. The N-acetyl-aspartate levels were reduced in 27 (96 %) spectra. Choline was increased in 3 (11 %), normal in 4 (14 %), and reduced in 21 (75 %) spectra. The creatine level was normal in 8 (29 %) spectra and reduced in 20 (71 %) spectra. Imaging showed 4 (14 %) spectra with category-I imaging findings; 5 (18 %) spectra with category-II findings; 15 (54 %) spectra with category-III findings; and 4 (14 %) spectra with category-IV findings. Magnetic resonance spectroscopy showed reduced N-acetyl-aspartate in radiation-induced temporal lobe changes. Creatine levels were relatively more stable. Choline levels may be increased, normal, or reduced. Imaging findings ranged from normal to contrast-enhancing lesions and cystic encephalomalacia. (orig.)

  17. Predictors of urinary and rectal toxicity after external conformed radiation therapy in prostate cancer: Correlation between clinical, tumour and dosimetric parameters and radical and postoperative radiation therapy.

    Science.gov (United States)

    Martínez-Arribas, C M; González-San Segundo, C; Cuesta-Álvaro, P; Calvo-Manuel, F A

    2017-06-15

    To determine rectal and urinary toxicity after external beam radiation therapy (EBRT), assessing the results of patients who undergo radical or postoperative therapy for prostate cancer (pancreatic cancer) and their correlation with potential risk factors. A total of 333 patients were treated with EBRT. Of these, 285 underwent radical therapy and 48 underwent postoperative therapy (39 cases of rescue and 9 of adjuvant therapy). We collected clinical, tumour and dosimetric variable to correlate with toxicity parameters. We developed decision trees based on the degree of statistical significance. The rate of severe acute toxicity, both urinary and rectal, was 5.4% and 1.5%, respectively. The rate of chronic toxicity was 4.5% and 2.7%, respectively. Twenty-seven patients presented haematuria, and 9 presented haemorrhagic rectitis. Twenty-five patients (7.5%) presented permanent limiting sequela. The patients with lower urinary tract symptoms prior to the radiation therapy presented poorer tolerance, with greater acute bladder toxicity (P=0.041). In terms of acute rectal toxicity, 63% of the patients with mean rectal doses >45Gy and anticoagulant/antiplatelet therapy developed mild toxicity compared with 37% of the patients with mean rectal doses <45 Gy and without anticoagulant therapy. We were unable to establish predictors of chronic toxicity in the multivariate analysis. The long-term sequelae were greater in the patients who underwent urological operations prior to the radiation therapy and who were undergoing anticoagulant therapy. The tolerance to EBRT was good, and severe toxicity was uncommon. Baseline urinary symptoms constitute the predictor that most influenced the acute urinary toxicity. Rectal toxicity is related to the mean rectal dose and with anticoagulant/antiplatelet therapy. There were no significant differences in severe toxicity between radical versus postoperative radiation therapy. Copyright © 2017 AEU. Publicado por Elsevier España, S

  18. Theoretical dosimetric evaluation of carbon and oxygen minibeam radiation therapy.

    Science.gov (United States)

    González, Wilfredo; Peucelle, Cécile; Prezado, Yolanda

    2017-05-01

    Charged particles have several advantages over x-ray radiations, both in terms of physics and radiobiology. The combination of these advantages with those of minibeam radiation therapy (MBRT) could help enhancing the therapeutic index for some cancers with poor prognosis. Among the different ions explored for therapy, carbon ions are considered to provide the optimum physical and biological characteristics. Oxygen could be advantageous due to a reduced oxygen enhancement ratio along with a still moderate biological entrance dose. The aforementioned reasons justified an in-depth evaluation of the dosimetric features of carbon and oxygen minibeam radiation therapy to establish the interest of further explorations of this avenue. The GATE/Geant4 6.2 Monte Carlo simulation platform was employed to simulate arrays of rectangular carbon and oxygen minibeams (600 μm × 2 cm) at a water phantom entrance. They were assumed to be generated by means of a magnetic focusing. The irradiations were performed with a 2-cm-long spread-out Bragg peak (SOBP) centered at 7-cm-depth. Several center-to-center (c-t-c) distances were considered. Peak and valley doses, as well as peak-to-valley dose ratio (PVDR) and the relative contribution of nuclear fragments and electromagnetic processes were assessed. In addition, the type and proportion of the secondary nuclear fragments were evaluated in both peak and valley regions. Carbon and oxygen MBRT lead to very similar dose distributions. No significant advantage of oxygen over carbon ions was observed from physical point of view. Favorable dosimetric features were observed for both ions. Thanks to the reduced lateral scattering, the standard shape of the depth dose curves (in the peaks) is maintained even for submillimetric beam sizes. When a narrow c-t-c is considered (910-980 μm), a (quasi) homogenization of the dose can be obtained at the target, while a spatial fractionation of the dose is maintained in the proximal normal tissues with

  19. Imaging Biomarker Dynamics in an Intracranial Murine Glioma Study of Radiation and Antiangiogenic Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Caroline, E-mail: caroline.chung@rmp.uhn.on.ca [Department of Radiation Oncology, University Health Network-Princess Margaret Hospital, Toronto, Ontario (Canada); Jalali, Shahrzad [Brain Tumor Research Centre, SickKids Hospital, Toronto, Ontario (Canada); Foltz, Warren [Department of Radiation Oncology, University Health Network-Princess Margaret Hospital, Ontario (Canada); Burrell, Kelly [Brain Tumor Research Centre, SickKids Hospital, Toronto, Ontario (Canada); Wildgoose, Petra; Lindsay, Patricia [Department of Radiation Oncology, University Health Network-Princess Margaret Hospital, Ontario (Canada); Graves, Christian; Camphausen, Kevin [Department of Radiation Oncology, National Cancer Institute, Bethesda, Maryland (United States); Milosevic, Michael; Jaffray, David [Department of Radiation Oncology, University Health Network-Princess Margaret Hospital, Toronto, Ontario (Canada); Zadeh, Gelareh [Neurosurgery, University Health Network-Toronto Western Hospital, Toronto, Ontario (Canada); Ménard, Cynthia [Department of Radiation Oncology, University Health Network-Princess Margaret Hospital, Toronto, Ontario (Canada)

    2013-03-01

    Purpose: There is a growing need for noninvasive biomarkers to guide individualized spatiotemporal delivery of radiation therapy (RT) and antiangiogenic (AA) therapy for brain tumors. This study explored early biomarkers of response to RT and the AA agent sunitinib (SU), in a murine intracranial glioma model, using serial magnetic resonance imaging (MRI). Methods and Materials: Mice with MRI-visible tumors were stratified by tumor size into 4 therapy arms: control, RT, SU, and SU plus RT (SURT). Single-fraction conformal RT was delivered using MRI and on-line cone beam computed tomography (CT) guidance. Serial MR images (T2-weighted, diffusion, dynamic contrast-enhanced and gadolinium-enhanced T1-weighted scans) were acquired biweekly to evaluate tumor volume, apparent diffusion coefficient (ADC), and tumor perfusion and permeability responses (K{sub trans}, K{sub ep}). Results: Mice in all treatment arms survived longer than those in control, with a median survival of 35 days for SURT (P<.0001) and 30 days for RT (P=.009) and SU (P=.01) mice vs 26 days for control mice. At Day 3, ADC rise was greater with RT than without (P=.002). Sunitinib treatment reduced tumor perfusion/permeability values with mean K{sub trans} reduction of 27.6% for SU (P=.04) and 26.3% for SURT (P=.04) mice and mean K{sub ep} reduction of 38.1% for SU (P=.01) and 27.3% for SURT (P=.02) mice. The magnitude of individual mouse ADC responses at Days 3 and 7 correlated with subsequent tumor growth rate R values of −0.878 (P=.002) and −0.80 (P=.01), respectively. Conclusions: Early quantitative changes in diffusion and perfusion MRI measures reflect treatment responses soon after starting therapy and thereby raise the potential for these imaging biomarkers to guide adaptive and potentially individualized therapy approaches in the future.

  20. Adaptive response and split-dose effect of radiation on the survival ...

    Indian Academy of Sciences (India)

    Although the importance of radiation-induced adaptive response has been recognized in human health, risk assessment and clinical application, the phenomenon has not been understood well in terms of survival of animals. To examine this aspect Swiss albino mice were irradiated with different doses (2–10 Gy) at 0.015 ...

  1. Managing Radiation Therapy Side Effects: What to Do about Feeling Sick to Your Stomach and Throwing Up (Nausea and ...

    Science.gov (United States)

    ... Radiation Therapy Side Effects What To Do About Feeling Sick to Your Stomach and Throwing Up (Nausea ... you eat it. Managing Radiation Therapy Side Effects: Feeling Sick to Your Stomach and Throwing Up (Nausea ...

  2. [Prognostic factors of hyperbaric oxygen therapy in hemorrhagic radiation cystitis].

    Science.gov (United States)

    Bouaziz, M; Genestal, M; Perez, G; Bou-Nasr, E; Latorzeff, I; Thoulouzan, M; Game, X; Soulie, M; Beauval, J-B; Huyghe, E

    2017-01-01

    To emphasize prognostic factors of hyperbaric oxygen therapy (HBOT) on hematuria at 3 and 12 months in the context of a radiation cystitis. A cohort of 134 patients was treated from 2008 to 2013 in the hyperbaric medicine center of Toulouse University Hospital, France for radiation cystitis. Hematuria was ranked using the SOMA score. HBOT has been applied according to a standardized protocol of 20 renewable sessions, with pure oxygen to 2.5 ATA. The median number of sessions at 12 months was 50. HBOT had an efficacy of 83% at 3 months and 81% at 12 months. Twenty percent of patients had minor side effects. Compared to the pre-HBOT period, the number of hospitalizations decreased by 75% following treatment. The efficacy at 3 months was predictive of efficacy at 12 months (P<0.0001). There was an inverse correlation between the initial grade and efficacy at 3 months (P=0.026) and 12 months (P=0.001). A high WHO status diminished HBOT efficacy at 3 and 12 months (P=0.0014 and P<0.0001, respectively). An anticoagulant intake decreased the HBOT response at 12 months (P=0.002). Other parameters had no effects on efficacy. The efficacy at 3 months seems to be predictive of efficacy at 12 months. The initial hematuria grade is inversely correlated with efficacy at 3 and 12 months. It appears necessary to achieve at least 32 HBOT sessions. Moreover, a high WHO status and an anticoagulant intake seem to have a negative prognostic value. 4. Copyright © 2016. Published by Elsevier Masson SAS.

  3. Proton Radiation Therapy for the Treatment of Retinoblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Mouw, Kent W. [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Sethi, Roshan V.; Yeap, Beow Y.; MacDonald, Shannon M.; Chen, Yen-Lin E.; Tarbell, Nancy J.; Yock, Torunn I.; Munzenrider, John E.; Adams, Judith [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Grabowski, Eric [Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts (United States); Mukai, Shizuo [Retina Service, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts (United States); Shih, Helen A., E-mail: hshih@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2014-11-15

    Purpose: To investigate long-term disease and toxicity outcomes for pediatric retinoblastoma patients treated with proton radiation therapy (PRT). Methods and Materials: This is a retrospective analysis of 49 retinoblastoma patients (60 eyes) treated with PRT between 1986 and 2012. Results: The majority (84%) of patients had bilateral disease, and nearly half (45%) had received prior chemotherapy. At a median follow-up of 8 years (range, 1-24 years), no patients died of retinoblastoma or developed metastatic disease. The post-PRT enucleation rate was low (18%), especially in patients with early-stage disease (11% for patients with International Classification for Intraocular Retinoblastoma [ICIR] stage A-B disease vs 23% for patients with ICIR stage C-D disease). Post-PRT ophthalmologic follow-up was available for 61% of the preserved eyes (30 of 49): 14 of 30 eyes (47%) had 20/40 visual acuity or better, 7 of 30 (23%) had moderate visual acuity (20/40-20/600), and 9 of 30 (30%) had little or no useful vision (worse than 20/600). Twelve of 60 treated eyes (20%) experienced a post-PRT event requiring intervention, with cataracts the most common (4 eyes). No patients developed an in-field second malignancy. Conclusions: Long-term follow-up of retinoblastoma patients treated with PRT demonstrates that PRT can achieve high local control rates, even in advanced cases, and many patients retain useful vision in the treated eye. Treatment-related ocular side effects were uncommon, and no radiation-associated malignancies were observed.

  4. Niche divergence facilitated by fine-scale ecological partitioning in a recent cichlid fish adaptive radiation.

    Science.gov (United States)

    Ford, Antonia G P; Rüber, Lukas; Newton, Jason; Dasmahapatra, Kanchon K; Balarin, John D; Bruun, Kristoffer; Day, Julia J

    2016-12-01

    Ecomorphological differentiation is a key feature of adaptive radiations, with a general trend for specialization and niche expansion following divergence. Ecological opportunity afforded by invasion of a new habitat is thought to act as an ecological release, facilitating divergence, and speciation. Here, we investigate trophic adaptive morphology and ecology of an endemic clade of oreochromine cichlid fishes (Alcolapia) that radiated along a herbivorous trophic axis following colonization of an isolated lacustrine environment, and demonstrate phenotype-environment correlation. Ecological and morphological divergence of the Alcolapia species flock are examined in a phylogenomic context, to infer ecological niche occupation within the radiation. Species divergence is observed in both ecology and morphology, supporting the importance of ecological speciation within the radiation. Comparison with an outgroup taxon reveals large-scale ecomorphological divergence but shallow genomic differentiation within the Alcolapia adaptive radiation. Ancestral morphological reconstruction suggests lake colonization by a generalist oreochromine phenotype that diverged in Lake Natron to varied herbivorous morphologies akin to specialist herbivores in Lakes Tanganyika and Malawi. © 2016 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

  5. Niche divergence facilitated by fine‐scale ecological partitioning in a recent cichlid fish adaptive radiation

    Science.gov (United States)

    Ford, Antonia G. P.; Rüber, Lukas; Newton, Jason; Dasmahapatra, Kanchon K.; Balarin, John D.; Bruun, Kristoffer; Day, Julia J.

    2016-01-01

    Ecomorphological differentiation is a key feature of adaptive radiations, with a general trend for specialization and niche expansion following divergence. Ecological opportunity afforded by invasion of a new habitat is thought to act as an ecological release, facilitating divergence, and speciation. Here, we investigate trophic adaptive morphology and ecology of an endemic clade of oreochromine cichlid fishes (Alcolapia) that radiated along a herbivorous trophic axis following colonization of an isolated lacustrine environment, and demonstrate phenotype‐environment correlation. Ecological and morphological divergence of the Alcolapia species flock are examined in a phylogenomic context, to infer ecological niche occupation within the radiation. Species divergence is observed in both ecology and morphology, supporting the importance of ecological speciation within the radiation. Comparison with an outgroup taxon reveals large‐scale ecomorphological divergence but shallow genomic differentiation within the Alcolapia adaptive radiation. Ancestral morphological reconstruction suggests lake colonization by a generalist oreochromine phenotype that diverged in Lake Natron to varied herbivorous morphologies akin to specialist herbivores in Lakes Tanganyika and Malawi. PMID:27659769

  6. Genomic variation at the tips of the adaptive radiation of Darwin's finches.

    Science.gov (United States)

    Chaves, Jaime A; Cooper, Elizabeth A; Hendry, Andrew P; Podos, Jeffrey; De León, Luis F; Raeymaekers, Joost A M; MacMillan, W Owen; Uy, J Albert C

    2016-11-01

    Adaptive radiation unfolds as selection acts on the genetic variation underlying functional traits. The nature of this variation can be revealed by studying the tips of an ongoing adaptive radiation. We studied genomic variation at the tips of the Darwin's finch radiation; specifically focusing on polymorphism within, and variation among, three sympatric species of the genus Geospiza. Using restriction site-associated DNA (RAD-seq), we characterized 32 569 single-nucleotide polymorphisms (SNPs), from which 11 outlier SNPs for beak and body size were uncovered by a genomewide association study (GWAS). Principal component analysis revealed that these 11 SNPs formed four statistically linked groups. Stepwise regression then revealed that the first PC score, which included 6 of the 11 top SNPs, explained over 80% of the variation in beak size, suggesting that selection on these traits influences multiple correlated loci. The two SNPs most strongly associated with beak size were near genes associated with beak morphology across deeper branches of the radiation: delta-like 1 homologue (DLK1) and high-mobility group AT-hook 2 (HMGA2). Our results suggest that (i) key adaptive traits are associated with a small fraction of the genome (11 of 32 569 SNPs), (ii) SNPs linked to the candidate genes are dispersed throughout the genome (on several chromosomes), and (iii) micro- and macro-evolutionary variation (roots and tips of the radiation) involve some shared and some unique genomic regions. © 2016 John Wiley & Sons Ltd.

  7. A Study of Pseudoprogression After Spine Stereotactic Body Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bahig, Houda; Simard, Dany [Department of Radiation Oncology, Centre Hospitalier de l' Université de Montréal, Montreal, Quebec (Canada); Létourneau, Laurent [Department of Radiology, Centre Hospitalier de l' Université de Montréal, Montreal, Quebec (Canada); Wong, Philip; Roberge, David; Filion, Edith; Donath, David [Department of Radiation Oncology, Centre Hospitalier de l' Université de Montréal, Montreal, Quebec (Canada); Sahgal, Arjun [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Masucci, Laura, E-mail: g.laura.masucci.chum@ssss.gouv.qc.ca [Department of Radiation Oncology, Centre Hospitalier de l' Université de Montréal, Montreal, Quebec (Canada)

    2016-11-15

    Purpose: To determine the incidence of pseudoprogression (PP) after spine stereotactic body radiation therapy based on a detailed and quantitative assessment of magnetic resonance imaging (MRI) morphologic tumor alterations, and to identify predictive factors distinguishing PP from local recurrence (LR). Methods and Materials: A retrospective analysis of 35 patients with 49 spinal segments treated with spine stereotactic body radiation therapy, from 2009 to 2014, was conducted. The median number of follow-up MRI studies was 4 (range, 2-7). The gross tumor volumes (GTVs) within each of the 49 spinal segments were contoured on the pretreatment and each subsequent follow-up T1- and T2-weighted MRI sagittal sequence. T2 signal intensity was reported as the mean intensity of voxels constituting each volume. LR was defined as persistent GTV enlargement on ≥2 serial MRI studies for ≥6 months or on pathologic confirmation. PP was defined as a GTV enlargement followed by stability or regression on subsequent imaging within 6 months. Kaplan-Meier analysis was used for estimation of actuarial local control, disease-free survival, and overall survival. Results: The median follow-up was 23 months (range, 1-39 months). PP was identified in 18% of treated segments (9 of 49) and LR in 29% (14 of 49). Earlier volume enlargement (5 months for PP vs 15 months for LR, P=.005), greater GTV to reference nonirradiated vertebral body T2 intensity ratio (+30% for PP vs −10% for LR, P=.005), and growth confined to 80% of the prescription isodose line (80% IDL) (8 of 9 PP cases vs 1 of 14 LR cases, P=.002) were associated with PP on univariate analysis. Multivariate analysis confirmed an earlier time to volume enlargement and growth within the 80% IDL as significant predictors of PP. LR involved the epidural space in all but 1 lesion, whereas PP was confined to the vertebral body in 7 of 9 cases. Conclusions: PP was observed in 18% of treated spinal segments. Tumor growth

  8. [Relapse prevention group therapy for paedophiles: French adaptation].

    Science.gov (United States)

    Smith, J; Petibon, C

    2005-01-01

    Psychotherapy for sex offenders has only very recently started to develop in France. The French law on compulsory treatment for sex offenders was voted in 1998, and many mental health practitioners are not trained to treat such patients yet. In our ambulatory forensic consultation, sex offenders have been treated since 1992 and group psychotherapy has been offered to them since 1994. Our first therapeutic models were the North-American behavioural-cognitive therapy and Pithers' relapse prevention model. Behavioural-cognitive theory describes paedophilia as an acquired sexual preference maintained by positive reinforcement. Pithers (1990) considered that relapse only occurs in high-risk situations, and that high-risk situations always come after offence precursors. In North America, relapse prevention consists in helping paedophiles spot their high-risk situations and offence precursors, and enhance their skills to cope with such situations or to prevent them. Therapy programs were developed according to these models, aiming to help offenders develop such skills, ie empathy, social skills, cognitive restructuring, self-esteem, etc. Trying to apply these therapy programs in France, our team quickly realised that we would have to adapt them to French culture. On the one hand, behavioural-cognitive theory did not seem satisfactory enough in explaining paedophilic behaviour and paedophilic preference. On the other hand, behavioural-cognitive therapy made patients into children too much and increased resistance. Therapy based on programs seemed too rigid for French patients and therapists, and we often felt we were working on an issue that would have been much more accurate to work on a few sessions earlier, when this issue was spontaneously brought up by a patient. We believe change occurs all the more as issues are worked on at the right moment for the patient. Moreover, on a cultural point of view, we also realised the use of programs in psychotherapy was difficult to

  9. Radiation therapy in the multimodal treatment approach of pituitary adenoma

    Energy Technology Data Exchange (ETDEWEB)

    Becker, G. [Klinik am Eichert, Goeppingen (Germany). Dept. of Radiooncology and Radiation Therapy; Radiooncologic Univ. Clinic, Tuebingen (Germany); Kocher, M.; Mueller, R.P. [Koeln Univ. (Germany). Clinic of Radiation Therapy; Kortmann, R.D.; Paulsen, F.; Jeremic, B.; Bamberg, M. [Radiooncologic Univ. Clinic, Tuebingen (Germany)

    2002-04-01

    In this paper, literature will be reviewed to assess the role of modern radiotherapy and radiosurgery in the management of pituitary adenomas. Material and Methods: Nowadays, magnetic resonance imaging for the definition of the target volume and a real three-dimensional (3-D) treatment planning with field conformation and the possibility for non-coplanar irradiation has to be recommended. Most groups irradiate these benign tumors with single doses of 1.8-2.0 Gy up to a total dose of 45 Gy or 50.4 Gy in extensive parasellar adenomas. Adenomas are mostly small, well circumscribed lesions, and have, therefore, attracted the use of stereotactically guided high-precision irradiation techniques which allow extreme focussing and provide steep dose gradients with selective treatment of the target and optimal protection of the surrounding brain tissue. Results: Radiation therapy controls tumor growth in 80-98% of patients with non-secreting adenomas and 67-89% for endocrine active tumors. Reviewing the recent literature including endocrine active and non-secreting adenomas, irradiated postoperatively or in case of recurrence the 5-, 10- and 15-year local control rates amount 92%, 89% and 79%. In cases of microprolactinoma primary therapy consists of dopamine agonists. Irradiation should be preferred in patients with macroprolactinomas, when drug therapy and/or surgery failed or for patients medically unsuitable for surgery. Reduction and control of prolactin secretion can be achieved in 44-70% of patients. After radiotherapy in acromegaly patients somatomedin-C and growth hormone concentrations decrease to normal levels in 70-90%, with a decrease rate of 10-30% per year. Hypercortisolism is controlled in 50-83% of adults and 80% of children with Cushing's disease, generally in less than 9 months. Hypopituitarism is the most common side effect of pituitary irradiation with an incidence of 13-56%. Long-term overall risk for brain necrosis in a total of 1,388 analyzed

  10. Adaptive radiation of island plants: Evidence from Aeonium (Crassulaceae) of the Canary Islands

    DEFF Research Database (Denmark)

    Jorgensen, T.H.; Olesen, J.M.

    2001-01-01

    The presence of diverse and species-rich plant lineages on oceanic islands is most often associated with adaptive radiation. Here we discuss the possible adaptive significance of some of the most prominent traits in island plants, including woodiness, monocarpy and sexual dimorphisms. Indirect...... discussion of the mechanisms governing radiations on islands. Most examples are from the Hawaiian and Canarian floras, and in particular from studies on the morphological, ecological and molecular diversification of the genus Aeonium, the largest plant radiation of the Canarian Islands....... evidence that such traits have been acquired through convergent evolution on islands comes from molecular phylogenies; however, direct evidence of their selective value rarely is obtained. The importance of hybridization in the evolution of island plants is also considered as part of a more general...

  11. Adaptive response in frogs chronically exposed to low doses of ionizing radiation in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Audette-Stuart, M., E-mail: stuartm@aecl.ca [Environmental Technologies Branch, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario, K0J 1P0 (Canada); Kim, S.B.; McMullin, D.; Festarini, A.; Yankovich, T.L.; Carr, J.; Mulpuru, S. [Environmental Technologies Branch, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario, K0J 1P0 (Canada)

    2011-06-15

    Using the micronucleus assay, decreased levels of DNA damage were found after high dose ionizing radiation exposure of liver cells taken from frogs inhabiting a natural environment with above-background levels of ionizing radiation, compared to cells taken from frogs inhabiting background areas. The data obtained from a small number of animals suggest that stress present in the above-background environment could induce an adaptive response to ionizing radiation. This study did not reveal harmful effects of exposure to low levels of radioactivity. On the contrary, stress present in the above-background area may serve to enhance cellular defense mechanisms. - Highlights: > Frogs were collected from background and higher tritium level habitats. > The micronucleus assay was conducted on liver cells obtained from the frogs. > No detrimental effects were noted in frogs exposed to elevated tritium. > Adaptive responses were observed in frogs exposed to elevated tritium.

  12. Adaptation is mandatory for intensity modulated proton therapy of advanced lung cancer to ensure target coverage

    DEFF Research Database (Denmark)

    Hoffmann, Lone; Alber, Markus; Jensen, Maria Fuglsang

    2017-01-01

    BACKGROUND AND PURPOSE: Large anatomical changes during radiotherapy are seen for a large proportion of lung cancer patients. We investigate the applicability of a decision support protocol for photon therapy in a proton therapy setting. MATERIAL AND METHODS: Twenty-three consecutive NSCLC patien...... in the positioning of the bones. CONCLUSIONS: Proton therapy for loco-regional lung cancer demands daily imaging and therapy adaptation for a high proportion of patients....

  13. Projections onto the Pareto surface in multicriteria radiation therapy optimization.

    Science.gov (United States)

    Bokrantz, Rasmus; Miettinen, Kaisa

    2015-10-01

    To eliminate or reduce the error to Pareto optimality that arises in Pareto surface navigation when the Pareto surface is approximated by a small number of plans. The authors propose to project the navigated plan onto the Pareto surface as a postprocessing step to the navigation. The projection attempts to find a Pareto optimal plan that is at least as good as or better than the initial navigated plan with respect to all objective functions. An augmented form of projection is also suggested where dose-volume histogram constraints are used to prevent that the projection causes a violation of some clinical goal. The projections were evaluated with respect to planning for intensity modulated radiation therapy delivered by step-and-shoot and sliding window and spot-scanned intensity modulated proton therapy. Retrospective plans were generated for a prostate and a head and neck case. The projections led to improved dose conformity and better sparing of organs at risk (OARs) for all three delivery techniques and both patient cases. The mean dose to OARs decreased by 3.1 Gy on average for the unconstrained form of the projection and by 2.0 Gy on average when dose-volume histogram constraints were used. No consistent improvements in target homogeneity were observed. There are situations when Pareto navigation leaves room for improvement in OAR sparing and dose conformity, for example, if the approximation of the Pareto surface is coarse or the problem formulation has too permissive constraints. A projection onto the Pareto surface can identify an inaccurate Pareto surface representation and, if necessary, improve the quality of the navigated plan.

  14. Regulation Of Nf=kb And Mnsod In Low Dose Radiation Induced Adaptive Protection Of Mouse And Human Skin Cells

    Energy Technology Data Exchange (ETDEWEB)

    Jian Li

    2012-11-07

    A sampling of publications resulting from this grant is provided. One is on the subject of NF-κB-Mediated HER2 Overexpression in Radiation-Adaptive Resistance. Another is on NF-κB-mediated adaptive resistance to ionizing radiation.

  15. Testing the stages model in the adaptive radiation of cichlid fishes in East African Lake Tanganyika

    Science.gov (United States)

    Muschick, Moritz; Nosil, Patrik; Roesti, Marius; Dittmann, Marie Theres; Harmon, Luke; Salzburger, Walter

    2014-01-01

    Adaptive radiation (AR) is a key process in the origin of organismal diversity. However, the evolution of trait disparity in connection with ecological specialization is still poorly understood. Available models for vertebrate ARs predict that diversification occurs in the form of temporal stages driven by different selective forces. Here, we investigate the AR of cichlid fishes in East African Lake Tanganyika and use macroevolutionary model fitting to evaluate whether diversification happened in temporal stages. Six trait complexes, for which we also provide evidence of their adaptiveness, are analysed with comparative methods: body shape, pharyngeal jaw shape, gill raker traits, gut length, brain weight and body coloration. Overall, we do not find strong evidence for the ‘stages model’ of AR. However, our results suggest that trophic traits diversify earlier than traits implicated in macrohabitat adaptation and that sexual communication traits (i.e. coloration) diversify late in the radiation. PMID:25274371

  16. Radiobiological mechanisms of stereotactic body radiation therapy and stereotactic radiation surgery

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Sook; Kim, Won Woo; Park, In Hwan; Kim, Hee Jong; Lee, Eun Jin; Jung, Jae Hoon [Research Center for Radiotherapy, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Cho, Lawrence Chin Soo; Song, Chang W. [Dept. of Radiation Oncology, University of Minnesota Medical School, Minneapolis (United States)

    2015-12-15

    Despite the increasing use of stereotactic body radiation therapy (SBRT) and stereotactic radiation surgery (SRS) in recent years, the biological base of these high-dose hypo-fractionated radiotherapy modalities has been elusive. Given that most human tumors contain radioresistant hypoxic tumor cells, the radiobiological principles for the conventional multiple-fractionated radiotherapy cannot account for the high efficacy of SBRT and SRS. Recent emerging evidence strongly indicates that SBRT and SRS not only directly kill tumor cells, but also destroy the tumor vascular beds, thereby deteriorating intratumor microenvironment leading to indirect tumor cell death. Furthermore, indications are that the massive release of tumor antigens from the tumor cells directly and indirectly killed by SBRT and SRS stimulate anti-tumor immunity, thereby suppressing recurrence and metastatic tumor growth. The reoxygenation, repair, repopulation, and redistribution, which are important components in the response of tumors to conventional fractionated radiotherapy, play relatively little role in SBRT and SRS. The linear-quadratic model, which accounts for only direct cell death has been suggested to overestimate the cell death by high dose per fraction irradiation. However, the model may in some clinical cases incidentally do not overestimate total cell death because high-dose irradiation causes additional cell death through indirect mechanisms. For the improvement of the efficacy of SBRT and SRS, further investigation is warranted to gain detailed insights into the mechanisms underlying the SBRT and SRS.

  17. A comprehensive dosimetric study of pancreatic cancer treatment using three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), volumetric-modulated radiation therapy (VMAT), and passive-scattering and modulated-scanning proton therapy (PT)

    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

  18. Radiation hydrodynamics using characteristics on adaptive decomposed domains for massively parallel star formation simulations

    Science.gov (United States)

    Buntemeyer, Lars; Banerjee, Robi; Peters, Thomas; Klassen, Mikhail; Pudritz, Ralph E.

    2016-02-01

    We present an algorithm for solving the radiative transfer problem on massively parallel computers using adaptive mesh refinement and domain decomposition. The solver is based on the method of characteristics which requires an adaptive raytracer that integrates the equation of radiative transfer. The radiation field is split into local and global components which are handled separately to overcome the non-locality problem. The solver is implemented in the framework of the magneto-hydrodynamics code FLASH and is coupled by an operator splitting step. The goal is the study of radiation in the context of star formation simulations with a focus on early disc formation and evolution. This requires a proper treatment of radiation physics that covers both the optically thin as well as the optically thick regimes and the transition region in particular. We successfully show the accuracy and feasibility of our method in a series of standard radiative transfer problems and two 3D collapse simulations resembling the early stages of protostar and disc formation.

  19. WE-A-BRF-01: Dual-Energy CT Imaging in Diagnostic Imaging and Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Molloi, S [University of California, Irvine, CA (United States); Li, B [Boston University Medical Center, Boston, MA (United States); Yin, F [Duke University Medical Center, Durham, NC (United States); Chen, H [New York Presbyterian Hospital, New York, NY (United States)

    2014-06-15

    classification based on calcium scores shows excellent agreement with classification on the basis of conventional coronary artery calcium scoring. These studies demonstrate dual-energy cardiovascular CT can potentially be a noninvasive and sensitive modality in high risk patients. On-board KV/MV Imaging. To enhance soft tissue contrast and reduce metal artifacts, we have developed a dual-energy CBCT technique and a novel on-board kV/MV imaging technique based on hardware available on modern linear accelerators. We have also evaluated the feasibility of these two techniques in various phantom studies. Optimal techniques (energy, beam filtration, # of overlapping projections, etc) have been investigated with unique calibration procedures, which leads to successful decomposition of imaged material into acrylic-aluminum basis material pair. This enables the synthesis of virtual monochromatic (VM) CBCT images that demonstrate much less beam hardening, significantly reduced metal artifacts, and/or higher soft tissue CNR compared to single-energy CBCT. Adaptive Radiation Therapy. DECT could actually contribute to the area of Dose-Guided Radiation Therapy (or Adaptive Therapy). The application of DECT imaging using 80kV and 140 kV combinations could potentially increase the image quality by reducing the bone or high density material artifacts and also increase the soft tissue contrast by a light contrast agent. The result of this higher contrast / quality images is beneficial for deformable image registration / segmentation algorithm to improve its accuracy hence to make adaptive therapy less time consuming in its recontouring process. The real time re-planning prior to per treatment fraction could become more realistic with this improvement especially in hypofractional SBRT cases. Learning Objectives: Learn recent developments of dual-energy imaging in diagnosis and radiation therapy; Understand the unique clinical problem and required quantification accuracy in each application

  20. Radiation Dose-Response Model for Locally Advanced Rectal Cancer After Preoperative Chemoradiation Therapy

    DEFF Research Database (Denmark)

    Appelt, A. L.; Ploen, J.; Vogelius, I. R.

    2013-01-01

    Purpose: Preoperative chemoradiation therapy (CRT) is part of the standard treatment of locally advanced rectal cancers. Tumor regression at the time of operation is desirable, but not much is known about the relationship between radiation dose and tumor regression. In the present study we...... estimated radiation dose-response curves for various grades of tumor regression after preoperative CRT. Methods and Materials: A total of 222 patients, treated with consistent chemotherapy and radiation therapy techniques, were considered for the analysis. Radiation therapy consisted of a combination...... of external-beam radiation therapy and brachytherapy. Response at the time of operation was evaluated from the histopathologic specimen and graded on a 5-point scale (TRG1-5). The probability of achieving complete, major, and partial response was analyzed by ordinal logistic regression, and the effect...

  1. Radiation immunomodulatory gene tumor therapy of rats with intracerebral glioma tumors

    DEFF Research Database (Denmark)

    Persson, Bertil R R; Koch, Catrin Bauréus; Grafström, Gustav

    2010-01-01

    Single-fraction radiation therapy with 5 or 15 Gy (60)Co gamma radiation was combined with intraperitoneal injections of syngeneic interferon gamma (IFN-gamma)-transfected cells in rats with intracerebral N29 or N32 glioma tumors at days 7, 21 and 35 after inoculation. For intracerebral N29 tumors......, single-fraction radiation therapy with 5 or 15 Gy had no significant effect on the survival time. Immunization with IFN-gamma-transfected N29 cells significantly increased the survival time by 61%. Single-fraction radiation therapy with 5 Gy combined with immunization increased the survival time...... significantly by 87% and complete remissions by 75% while with 15 Gy the survival time increased 45% with 38% complete remissions. For intracerebral N32 tumors, single-fraction radiation therapy with 15 Gy increased the survival time significantly by 20%. Immunization by itself had no significant effect...

  2. The Role of Alternative Splicing and Differential Gene Expression in Cichlid Adaptive Radiation.

    Science.gov (United States)

    Singh, Pooja; Börger, Christine; More, Heather; Sturmbauer, Christian

    2017-10-01

    Species diverge eco-morphologically through the continuous action of natural selection on functionally important structures, producing alternative adaptive morphologies. In cichlid fishes, the oral and pharyngeal jaws are such key structures. Adaptive variation in jaw morphology contributes to trophic specialization, which is hypothesized to fuel their rapid speciation in the East African Great Lakes. Much is known about the genes involved in cichlid jaw and craniofacial development. However, it is still unclear what salient sources of variation gave rise to trophic-niche specialization, facilitating adaptive radiation. Here, we explore two sources of transcriptional variation that may underlie species-specific disparities in jaw morphology. Using whole transcriptome RNA-sequencing, we analyze differences in gene expression and alternative splicing, at the end of postlarval development, in fully functional jaws of six species of cichlids from the Lake Tanganyika tribe Tropheini. Our data reveal a surprisingly high degree of alternative splicing events compared with gene expression differences among species and trophic types. This suggests that differential trophic adaptation of the jaw apparatus may have been shaped by transcriptional rewiring of splicing as well as gene expression variation during the rapid radiation of the Tropheini. Specifically, genes undergoing splicing across most species were found to be enriched for pharyngeal jaw gene ontology terms. Overall, jaw transcriptional patterns at postlarval developmental stage were highly dynamic and species-specific. In conclusion, this work indicates that shifts in alternative splicing could have played a more important role in cichlid adaptive radiation, and possibly adaptive radiation in general, than currently recognized. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  3. An adaptive radiation model for the origin of new genefunctions

    Energy Technology Data Exchange (ETDEWEB)

    Francino, M. Pilar

    2004-10-18

    The evolution of new gene functions is one of the keys to evolutionary innovation. Most novel functions result from gene duplication followed by divergence. However, the models hitherto proposed to account for this process are not fully satisfactory. The classic model of neofunctionalization holds that the two paralogous gene copies resulting from a duplication are functionally redundant, such that one of them can evolve under no functional constraints and occasionally acquire a new function. This model lacks a convincing mechanism for the new gene copies to increase in frequency in the population and survive the mutational load expected to accumulate under neutrality, before the acquisition of the rare beneficial mutations that would confer new functionality. The subfunctionalization model has been proposed as an alternative way to generate genes with altered functions. This model also assumes that new paralogous gene copies are functionally redundant and therefore neutral, but it predicts that relaxed selection will affect both gene copies such that some of the capabilities of the parent gene will disappear in one of the copies and be retained in the other. Thus, the functions originally present in a single gene will be partitioned between the two descendant copies. However, although this model can explain increases in gene number, it does not really address the main evolutionary question, which is the development of new biochemical capabilities. Recently, a new concept has been introduced into the gene evolution literature which is most likely to help solve this dilemma. The key point is to allow for a period of natural selection for the duplication per se, before new function evolves, rather than considering gene duplication to be neutral as in the previous models. Here, I suggest a new model that draws on the advantage of postulating selection for gene duplication, and proposes that bursts of adaptive gene amplification in response to specific selection

  4. Head and neck soft tissue sarcomas treated with radiation therapy

    Directory of Open Access Journals (Sweden)

    Lucas K. Vitzthum

    2016-06-01

    Full Text Available Head and neck soft tissue sarcomas (HNSTSs are rare and heterogeneous cancers in which radiation therapy (RT has an important role in local tumor control (LC. The purpose of this study was to evaluate outcomes and patterns of treatment failure in patients with HNSTS treated with RT. A retrospective review was performed of adult patients with HNSTS treated with RT from January 1, 1998, to December 31, 2012. LC, locoregional control (LRC, disease-free survival (DFS, overall survival (OS, and predictors thereof were assessed. Forty-eight patients with HNSTS were evaluated. Five-year Kaplan-Meier estimates of LC, LRC, DFS, and OS were 87, 73, 63, and 83%, respectively. Angiosarcomas were found to be associated with worse LC, LRC, DFS, and OS. Patients over the age of 60 had lower rates of DFS. HNSTSs comprise a diverse group of tumors that can be managed with various treatment regimens involving RT. Angiosarcomas have higher recurrence and mortality rates.

  5. Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System

    Energy Technology Data Exchange (ETDEWEB)

    Eigler, N.; Whiting, J.; Chernomorsky, A.; Jackson, J.; Knapp, F.F., Jr.; Litvack, F.

    1998-01-16

    RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Champion{trademark} over-the-wire, and TNT{trademark} rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors.

  6. [Big data and their perspectives in radiation therapy].

    Science.gov (United States)

    Guihard, Sébastien; Thariat, Juliette; Clavier, Jean-Baptiste

    2017-02-01

    The concept of big data indicates a change of scale in the use of data and data aggregation into large databases through improved computer technology. One of the current challenges in the creation of big data in the context of radiation therapy is the transformation of routine care items into dark data, i.e. data not yet collected, and the fusion of databases collecting different types of information (dose-volume histograms and toxicity data for example). Processes and infrastructures devoted to big data collection should not impact negatively on the doctor-patient relationship, the general process of care or the quality of the data collected. The use of big data requires a collective effort of physicians, physicists, software manufacturers and health authorities to create, organize and exploit big data in radiotherapy and, beyond, oncology. Big data involve a new culture to build an appropriate infrastructure legally and ethically. Processes and issues are discussed in this article. Copyright © 2016 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  7. Radiation therapy for symptomatic hepatomegaly in myelofibrosis with myeloid metaplasia

    Energy Technology Data Exchange (ETDEWEB)

    Tefferi, A.; Jimenez, T.; Gray, L.A.; Mesa, R.A. [Division of Hematology and Internal Medicine, Rochester, MN (United States); Chen, M.G. [Division of Radiation Oncology, Mayo Clinic and Mayo Foundation, MN (United States)

    2001-07-01

    Objective: To describe the experience with liver irradiation in advanced cases of myelofibrosis with myeloid metaplasia (MMM). Methods: Over a 20-yr period, 14 patients with MMM were treated with a total of 25 courses of liver, abdominal, or abdominal and pelvic irradiation for symptomatic hepatomegaly with (5 patients) or without (9 patients) ascites. All 14 patients had advanced disease and 11 (79%) had previous splenectomy. The median radiation therapy (RT) dose per course was 150 cGy (range 50-1000) administered at a median of six fractions. Four patients received two to six courses. Results. Twelve of the 14 patients (86%) had a transient (median 3 months) subjective response from RT. However, in only 35% of these was there a transient (median 3 months) decrease in palpable liver size. Four of the five patients with ascites experienced a short-term response from RT. Eight of the 13 patients suitable for evaluation (62%) had treatment-associated cytopenia, often in the form of anemia and/or thrombocytopenia. At last follow-up, 10 patients (71%) had died after a median of 7 months (range 0.1-23) and 4 were alive at 3, 20, 33, and 57 months after RT. Conclusions: Low-dose abdominal RT for symptomatic hepatomegaly or ascites associated with advanced-stage MMM is myelosuppressive and provides only temporary and mainly subjective and short-lived relief. (au)

  8. Immobilization for the radiation therapy treatment of the pelvic region

    Energy Technology Data Exchange (ETDEWEB)

    Van den Heuvel, F.; De Beukeleer, M.; Nys, F.; Bijdekerke, P.; Robberechts, M.; Van Cauwenbergh, R. [Brussels Univ. (Belgium). Dept. of Radiotherapy

    1995-12-01

    Previous experience with the treatment of the pelvic region has shown that geometric setup errors are considerable in extent and incidence. A proposal to alleviate this problem is the introduction of immobilization devices in analogy with head and neck treatment. The practicality and efficacy of such a technique is investigated and compared with an earlier proposed technique using interactive adjustment and Electronic Portal Imaging (EPI). A group of 13 patients treated in the pelvic region using external radiation therapy was immobilized using an Orfit-like cast. Every fraction for every patients was imaged using an EPID. Immediately after obtaining an image it was compared to a digitized simulation image using the in-house developed OPIDUM system. Patient position was adjusted when an error in one of the main directions (transversal or longitudinal) exceeded 5 mm. Time measurements were carried out in order to asses the impact of the immobilization procedure on the patient throughput. In 68% of the cases a corrective action was necessary. The fraction of total treatment time was 50% for 26% of the fields. The range of errors measured in the longitudinal direction was between 29 and -22 mm. In the transversal direction the range was from -7 to 60 mm. A full analysis 13 patients yielding statistics for more than 200 fields is presented. Special attention has been paid to the determination of the nature of the errors (random or systematic) and the impact on patient throughput.

  9. Conformal proton radiation therapy for pediatric low-grade astrocytomas

    Energy Technology Data Exchange (ETDEWEB)

    Hug, E.B. [Loma Linda Univ. Medical Center, Loma Linda, CA (United States). Dept. of Radiation Medicine; Loma Linda Univ. Medical Center, Loma Linda, CA (United States). Dept. of Pediatrics and Dept. of Pathology; Darthmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States). Section of Radiation Oncology; Muenter, M.W.; Archambeau, J.O.; DeVries, A.; Loredo, L.N.; Grove, R.I.; Slater, J.D. [Loma Linda Univ. Medical Center, Loma Linda, CA (United States). Dept. of Radiation Medicine; Liwnicz, B. [Loma Linda Univ. Medical Center, Loma Linda, CA (United States). Dept. of Pathology

    2002-01-01

    Background: To evaluate the safety and efficacy of proton radiation therapy (PRT) for intracranial low-grade astrocytomas, the authors analyzed the first 27 pediatric patients treated at Loma Linda University Medical Center (LLUMC). Patients and Method: Between September 1991 and August 1997, 27 patients (13 female, 14 male) underwent fractionated proton radiation therapy for progressive or recurrent low-grade astrocytoma. Age at time of treatment ranged from 2 to 18 years (mean: 8.7 years). Tumors were located centrally (diencephatic) in 15 patients, in the cerebral and cerebellar hemispheres in seven patients, and in the brainstem in five patients. 25/27 patients (92%) were treated for progressive, unresectable, or residual disease following subtotal resection. Tissue diagnosis was available in 23/27 patients (85%). Four patients with optic pathway tumors were treated without histologic confirmation. Target doses between 50.4 and 63.0 CGE (cobalt gray equivalent, mean: 55.2 CGE) were prescribed at 1.8 CGE per fraction, five treatments per week. Results: At a mean follow-up period of 3.3 years (0.6-6.8 years), 6/27 patients experienced local failure (all located within the irradiated field), and 4/27 patients had died. By anatomic site these data translated into rates of local control and survival of 87% (13/15 patients) and 93% (14/15 patients) for central tumors, 71% (5/7 patients) and 86% (6/7 patients) for hemispheric tumors, and 60% (3/5 patients) and 60% (3/5 patients) for tumors located in the brainstem. Proton radiation therapy was generally well tolerated. All children with local control maintained their performance status. One child with associated neurofibromatosis, Type 1, developed Moyamoya disease. All six patients with optic pathway tumors and useful vision maintained or improved their visual status. Conclusions: This report on pediatric low-grade astrocytomas confirms proton radiation therapy as a safe and efficacious 3-D conformal treatment

  10. Prostate Cancer Radiation Therapy and Risk of Thromboembolic Events

    Energy Technology Data Exchange (ETDEWEB)

    Bosco, Cecilia, E-mail: Cecilia.t.bosco@kcl.ac.uk [Translational Oncology & Urology Research (TOUR), Division of Cancer Studies, King' s College London, London (United Kingdom); Garmo, Hans [Translational Oncology & Urology Research (TOUR), Division of Cancer Studies, King' s College London, London (United Kingdom); Regional Cancer Centre, Uppsala, Akademiska Sjukhuset, Uppsala (Sweden); Adolfsson, Jan [CLINTEC Department, Karolinska Institutet, Stockholm (Sweden); Stattin, Pär [Department of Surgical Sciences, Uppsala University, Uppsala (Sweden); Department of Surgical and Perioperative Sciences, Urology and Andrology, Umeå University, Umeå (Sweden); Holmberg, Lars [Translational Oncology & Urology Research (TOUR), Division of Cancer Studies, King' s College London, London (United Kingdom); Regional Cancer Centre, Uppsala, Akademiska Sjukhuset, Uppsala (Sweden); Department of Surgical Sciences, Uppsala University, Uppsala (Sweden); Nilsson, Per; Gunnlaugsson, Adalsteinn [Department of Hematology, Oncology and Radiation Physics, Skane University Hospital, Lund University, Lund (Sweden); Widmark, Anders [Department of Radiation Sciences, Oncology, Umeå University, Umeå (Sweden); Van Hemelrijck, Mieke [Translational Oncology & Urology Research (TOUR), Division of Cancer Studies, King' s College London, London (United Kingdom); Institute of Environmental Medicine, Karolinska Institute, Stockholm (Sweden)

    2017-04-01

    Purpose: To investigate the risk of thromboembolic disease (TED) after radiation therapy (RT) with curative intent for prostate cancer (PCa). Patients and Methods: We identified all men who received RT as curative treatment (n=9410) and grouped according to external beam RT (EBRT) or brachytherapy (BT). By comparing with an age- and county-matched comparison cohort of PCa-free men (n=46,826), we investigated risk of TED after RT using Cox proportional hazard regression models. The model was adjusted for tumor characteristics, demographics, comorbidities, PCa treatments, and known risk factors of TED, such as recent surgery and disease progression. Results: Between 2006 and 2013, 6232 men with PCa received EBRT, and 3178 underwent BT. A statistically significant association was found between EBRT and BT and risk of pulmonary embolism in the crude analysis. However, upon adjusting for known TED risk factors these associations disappeared. No significant associations were found between BT or EBRT and deep venous thrombosis. Conclusion: Curative RT for prostate cancer using contemporary methodologies was not associated with an increased risk of TED.

  11. 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

  12. Age disparity in palliative radiation therapy among patients with advanced cancer.

    Science.gov (United States)

    Wong, Jonathan; Xu, Beibei; Yeung, Heidi N; Roeland, Eric J; Martinez, Maria Elena; Le, Quynh-Thu; Mell, Loren K; Murphy, James D

    2014-09-01

    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. 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. 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 Ppalliative 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 of life. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Medical physics aspects of the synchrotron radiation therapies: Microbeam radiation therapy (MRT) and synchrotron stereotactic radiotherapy (SSRT).

    Science.gov (United States)

    Bräuer-Krisch, Elke; Adam, Jean-Francois; Alagoz, Enver; Bartzsch, Stefan; Crosbie, Jeff; DeWagter, Carlos; Dipuglia, Andrew; Donzelli, Mattia; Doran, Simon; Fournier, Pauline; Kalef-Ezra, John; Kock, Angela; Lerch, Michael; McErlean, Ciara; Oelfke, Uwe; Olko, Pawel; Petasecca, Marco; Povoli, Marco; Rosenfeld, Anatoly; Siegbahn, Erik A; Sporea, Dan; Stugu, Bjarne

    2015-09-01

    Stereotactic Synchrotron Radiotherapy (SSRT) and Microbeam Radiation Therapy (MRT) are both novel approaches to treat brain tumor and potentially other tumors using synchrotron radiation. Although the techniques differ by their principles, SSRT and MRT share certain common aspects with the possibility of combining their advantages in the future. For MRT, the technique uses highly collimated, quasi-parallel arrays of X-ray microbeams between 50 and 600 keV. Important features of highly brilliant Synchrotron sources are a very small beam divergence and an extremely high dose rate. The minimal beam divergence allows the insertion of so called Multi Slit Collimators (MSC) to produce spatially fractionated beams of typically ∼25-75 micron-wide microplanar beams separated by wider (100-400 microns center-to-center(ctc)) spaces with a very sharp penumbra. Peak entrance doses of several hundreds of Gy are extremely well tolerated by normal tissues and at the same time provide a higher therapeutic index for various tumor models in rodents. The hypothesis of a selective radio-vulnerability of the tumor vasculature versus normal blood vessels by MRT was recently more solidified. SSRT (Synchrotron Stereotactic Radiotherapy) is based on a local drug uptake of high-Z elements in tumors followed by stereotactic irradiation with 80 keV photons to enhance the dose deposition only within the tumor. With SSRT already in its clinical trial stage at the ESRF, most medical physics problems are already solved and the implemented solutions are briefly described, while the medical physics aspects in MRT will be discussed in more detail in this paper. Copyright © 2015. Published by Elsevier Ltd.

  14. Modern Radiation Therapy for Hodgkin Lymphoma: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group (ILROG)

    Energy Technology Data Exchange (ETDEWEB)

    Specht, Lena, E-mail: lena.specht@regionh.dk [Department of Oncology and Hematology, Rigshospitalet, University of Copenhagen (Denmark); Yahalom, Joachim [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Illidge, Tim [Institute of Cancer Sciences, University of Manchester, Manchester Academic Health Sciences Centre, Christie Hospital NHS Trust, Manchester (United Kingdom); Berthelsen, Anne Kiil [Department of Radiation Oncology and PET Centre, Rigshospitalet, University of Copenhagen (Denmark); Constine, Louis S. [Department of Radiation Oncology and Pediatrics, James P. Wilmot Cancer Center, University of Rochester Medical Center, Rochester, New York (United States); Eich, Hans Theodor [Department of Radiation Oncology, University of Münster (Germany); Girinsky, Theodore [Department of Radiation Oncology, Institut Gustave-Roussy, Villejuif (France); Hoppe, Richard T. [Department of Radiation Oncology, Stanford University, Stanford, California (United States); Mauch, Peter [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Harvard University, Boston, Massachusetts (United States); Mikhaeel, N. George [Department of Clinical Oncology and Radiotherapy, Guy' s and St Thomas' NHS Foundation Trust, London (United Kingdom); Ng, Andrea [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Harvard University, Boston, Massachusetts (United States)

    2014-07-15

    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 volumes and doses is addressed, integrating modern imaging with 3-dimensional (3D) planning and advanced techniques of treatment delivery. The previously applied extended field (EF) and original involved field (IF) techniques, which treated larger volumes based on nodal stations, have now been replaced by the use of limited volumes, based solely on detectable nodal (and extranodal extension) involvement at presentation, using contrast-enhanced computed tomography, positron emission tomography/computed tomography, magnetic resonance imaging, or a combination of these techniques. The International Commission 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 optimal imaging is available, is explained. A new concept, involved site radiation therapy (ISRT), is introduced as the standard conformal therapy for the scenario, commonly encountered, wherein optimal imaging is not available. There is increasing evidence that RT doses used in the past are higher than necessary for disease control in this era of combined modality therapy. The use of INRT and of lower doses in early-stage HL is supported by available data. Although the

  15. Candidate genes and adaptive radiation: insights from transcriptional adaptation to the limnetic niche among coregonine fishes (Coregonus spp., Salmonidae).

    Science.gov (United States)

    Jeukens, Julie; Bittner, David; Knudsen, Rune; Bernatchez, Louis

    2009-01-01

    In the past 40 years, there has been increasing acceptance that variation in levels of gene expression represents a major source of evolutionary novelty. Gene expression divergence is therefore likely to be involved in the emergence of incipient species, namely, in a context of adaptive radiation. In the lake whitefish species complex (Coregonus clupeaformis), previous microarray experiments have led to the identification of candidate genes potentially implicated in the parallel evolution of the limnetic dwarf lake whitefish, which is highly distinct from the benthic normal lake whitefish in life history, morphology, metabolism, and behavior, and yet diverged from it only approximately 15,000 years before present. The aim of the present study was to address transcriptional divergence for six candidate genes among lake whitefish and European whitefish (Coregonus lavaretus) species pairs, as well as lake cisco (Coregonus artedi) and vendace (Coregonus albula). The main goal was to test the hypothesis that parallel phenotypic adaptation toward the use of the limnetic niche in coregonine fishes is accompanied by parallelism in candidate gene transcription as measured by quantitative real-time polymerase chain reaction. Results obtained for three candidate genes, whereby parallelism in expression was observed across all whitefish species pairs, provide strong support for the hypothesis that divergent natural selection plays an important role in the adaptive radiation of whitefish species. However, this parallelism in expression did not extend to cisco and vendace, thereby infirming transcriptional convergence between limnetic whitefish species and their limnetic congeners for these genes. As recently proposed (Lynch 2007a. The evolution of genetic networks by non-adaptive processes. Nat Rev Genet. 8:803-813), these results may suggest that convergent phenotypic evolution can result from nonadaptive shaping of genome architecture in independently evolved coregonine

  16. Cost-Effectiveness of Surgery, Stereotactic Body Radiation Therapy, and Systemic Therapy for Pulmonary Oligometastases

    Energy Technology Data Exchange (ETDEWEB)

    Lester-Coll, Nataniel H., E-mail: nataniel.lester-coll@yale.edu [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Rutter, Charles E.; Bledsoe, Trevor J. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Goldberg, Sarah B. [Department of Medicine (Medical Oncology), Yale University School of Medicine, New Haven, Connecticut (United States); Decker, Roy H.; Yu, James B. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States)

    2016-06-01

    Introduction: Pulmonary oligometastases have conventionally been managed with surgery and/or systemic therapy. However, given concerns about the high cost of systemic therapy and improvements in local treatment of metastatic cancer, the optimal cost-effective management of these patients is unclear. Therefore, we sought to assess the cost-effectiveness of initial management strategies for pulmonary oligometastases. Methods and Materials: A cost-effectiveness analysis using a Markov modeling approach was used to compare average cumulative costs, quality adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) among 3 initial disease management strategies: video-assisted thoracic surgery (VATS) wedge resection, stereotactic body radiation therapy (SBRT), and systemic therapy among 5 different cohorts of patient disease: (1) melanoma; (2) non-small cell lung cancer adenocarcinoma without an EGFR mutation (NSCLC AC); (3) NSCLC with an EGFR mutation (NSCLC EGFRm AC); (4) NSCLC squamous cell carcinoma (NSCLC SCC); and (5) colon cancer. One-way sensitivity analyses and probabilistic sensitivity analyses were performed to analyze uncertainty with regard to model parameters. Results: In the base case, SBRT was cost effective for melanoma, with costs/net QALYs of $467,787/0.85. In patients with NSCLC, the most cost-effective strategies were SBRT for AC ($156,725/0.80), paclitaxel/carboplatin for SCC ($123,799/0.48), and erlotinib for EGFRm AC ($147,091/1.90). Stereotactic body radiation therapy was marginally cost-effective for EGFRm AC compared to erlotinib with an incremental cost-effectiveness ratio of $126,303/QALY. For colon cancer, VATS wedge resection ($147,730/2.14) was the most cost-effective strategy. Variables with the greatest influence in the model were erlotinib-associated progression-free survival (EGFRm AC), toxicity (EGFRm AC), cost of SBRT (NSCLC SCC), and patient utilities (all histologies). Conclusions: Video-assisted thoracic

  17. 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.

  18. Complete adrenocorticotropin deficiency after radiation therapy for brain tumor with a normal growth hormone reserve

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Haruna; Yoshioka, Katsunobu; Yamagami, Keiko [Osaka City General Hospital (Japan)] (and others)

    2002-06-01

    A 34-year-old man with neurofibromatosis type 1, who had received radiation therapy after the excision of a brain tumor 5 years earlier, was admitted to our hospital with vomiting and weight loss. Cortisol and adrenocorticotropin (ACTH) were undetectable before and after administration of 100 {mu}g corticotropin releasing hormone. The level of growth hormone without stimulation was 24.7 ng/ml. We diagnosed him to have complete ACTH deficiency attributable to radiation therapy. This is the first known case of a patient with complete ACTH deficiency after radiation therapy and a growth hormone reserve that remained normal. (author)

  19. Jaw mobility changes in patients with upper aerodigestive tract cancer undergoing radiation therapy.

    Science.gov (United States)

    Bragante, Karoline; Wienandts, Patrícia; Mozzini, Carolina; Pinto, Rosélie; da Motta, Neiro; Jotz, Geraldo

    2015-11-01

    Radiation therapy is a therapeutic modality widely used for treatment of upper aerodigestive tract (UADT) neoplasms. However, its action is not restricted to tumor cells, and it may cause a variety of adverse reactions, including reduced jaw mobility. A prospective cohort study was conducted to assess changes in jaw mobility in patients with UADT cancer undergoing radiation therapy. Fifty-six patients completed the study. The results showed a significant reduction in mouth opening (pcancer experience reduced jaw mobility after radiation therapy, which is strongly correlated with mucositis and reduced functional ability.

  20. Imaging and characterization of primary and secondary radiation in ion beam therapy

    Energy Technology Data Exchange (ETDEWEB)

    Granja, Carlos, E-mail: carlos.granja@utef.cvut.cz; Opalka, Lukas [Institute of Experimental and Applied Physics, Czech Technical University in Prague (Czech Republic); Martisikova, Maria; Gwosch, Klaus [German Cancer Research Center, Heidelberg (Germany); Jakubek, Jan [Advacam, Prague (Czech Republic)

    2016-07-07

    Imaging in ion beam therapy is an essential and increasingly significant tool for treatment planning and radiation and dose deposition verification. Efforts aim at providing precise radiation field characterization and online monitoring of radiation dose distribution. A review is given of the research and methodology of quantum-imaging, composition, spectral and directional characterization of the mixed-radiation fields in proton and light ion beam therapy developed by the IEAP CTU Prague and HIT Heidelberg group. Results include non-invasive imaging of dose deposition and primary beam online monitoring.

  1. Computational Modeling of Medical Images of Brain Tumor Patients for Optimized Radiation Therapy Planning

    DEFF Research Database (Denmark)

    Agn, Mikael

    In brain tumor radiation therapy, the aim is to maximize the delivered radiation dose to the targeted tumor and at the same time minimize the dose to sensitive healthy structures – so-called organs-at-risk (OARs). When planning a radiation therapy session, the tumor and the OARs therefore need...... to be delineated on medical images of the patient’s head, to be able to optimize a radiation dose plan. In clinical practice, the delineation is performed manually with limited assistance from automatic procedures, which is both time-consuming and typically suffers from poor reproducibility. There is, therefore...

  2. "Intelligent Ensemble" Projections of Precipitation and Surface Radiation in Support of Agricultural Climate Change Adaptation

    Science.gov (United States)

    Taylor, Patrick C.; Baker, Noel C.

    2015-01-01

    Earth's climate is changing and will continue to change into the foreseeable future. Expected changes in the climatological distribution of precipitation, surface temperature, and surface solar radiation will significantly impact agriculture. Adaptation strategies are, therefore, required to reduce the agricultural impacts of climate change. Climate change projections of precipitation, surface temperature, and surface solar radiation distributions are necessary input for adaption planning studies. These projections are conventionally constructed from an ensemble of climate model simulations (e.g., the Coupled Model Intercomparison Project 5 (CMIP5)) as an equal weighted average, one model one vote. Each climate model, however, represents the array of climate-relevant physical processes with varying degrees of fidelity influencing the projection of individual climate variables differently. Presented here is a new approach, termed the "Intelligent Ensemble, that constructs climate variable projections by weighting each model according to its ability to represent key physical processes, e.g., precipitation probability distribution. This approach provides added value over the equal weighted average method. Physical process metrics applied in the "Intelligent Ensemble" method are created using a combination of NASA and NOAA satellite and surface-based cloud, radiation, temperature, and precipitation data sets. The "Intelligent Ensemble" method is applied to the RCP4.5 and RCP8.5 anthropogenic climate forcing simulations within the CMIP5 archive to develop a set of climate change scenarios for precipitation, temperature, and surface solar radiation in each USDA Farm Resource Region for use in climate change adaptation studies.

  3. Adaptive/Nonadaptive Proton Radiation Planning and Outcomes in a Phase II Trial for Locally Advanced Non-small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Koay, Eugene J.; Lege, David [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mohan, Radhe [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Komaki, Ritsuko; Cox, James D. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Chang, Joe Y., E-mail: jychang@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2012-12-01

    Purpose: To analyze dosimetric variables and outcomes after adaptive replanning of radiation therapy during concurrent high-dose protons and chemotherapy for locally advanced non-small cell lung cancer (NSCLC). Methods and Materials: Nine of 44 patients with stage III NSCLC in a prospective phase II trial of concurrent paclitaxel/carboplatin with proton radiation [74 Gy(RBE) in 37 fractions] had modifications to their original treatment plans after re-evaluation revealed changes that would compromise coverage of the target volume or violate dose constraints; plans for the other 35 patients were not changed. We compared patients with adaptive plans with those with nonadaptive plans in terms of dosimetry and outcomes. Results: At a median follow-up of 21.2 months (median overall survival, 29.6 months), no differences were found in local, regional, or distant failure or overall survival between groups. Adaptive planning was used more often for large tumors that shrank to a greater extent (median, 107.1 cm{sup 3} adaptive and 86.4 cm{sup 3} nonadaptive; median changes in volume, 25.3% adaptive and 1.2% nonadaptive; P<.01). The median number of fractions delivered using adaptive planning was 13 (range, 4-22). Adaptive planning generally improved sparing of the esophagus (median absolute decrease in V{sub 70}, 1.8%; range, 0%-22.9%) and spinal cord (median absolute change in maximum dose, 3.7 Gy; range, 0-13.8 Gy). Without adaptive replanning, target coverage would have been compromised in 2 cases (57% and 82% coverage without adaptation vs 100% for both with adaptation); neither patient experienced local failure. Radiation-related grade 3 toxicity rates were similar between groups. Conclusions: Adaptive planning can reduce normal tissue doses and prevent target misses, particularly for patients with large tumors that shrink substantially during therapy. Adaptive plans seem to have acceptable toxicity and achieve similar local, regional, and distant control and overall

  4. SU-F-J-57: Effectiveness of Daily CT-Based Three-Dimensional Image Guided and Adaptive Proton Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Moriya, S [University of Tsukuba, Tsukuba, Ibaraki (Japan); National Cancer Center, Kashiwa, Chiba (Japan); Tachibana, H; Hotta, K; Baba, H; Kohno, R; Akimoto, T [National Cancer Center, Kashiwa, Chiba (Japan); Nakamura, N [National Cancer Center Hospital East, Kashiwa, Chiba (Japan); Miyakawa, S; Kurosawa, T [Komazawa University, Setagaya, Tokyo (Japan)

    2016-06-15

    Purpose: Daily CT-based three-dimensional image-guided and adaptive (CTIGRT-ART) proton therapy system was designed and developed. We also evaluated the effectiveness of the CTIGRT-ART. Methods: Retrospective analysis was performed in three lung cancer patients: Proton treatment planning was performed using CT image datasets acquired by Toshiba Aquilion ONE. Planning target volume and surrounding organs were contoured by a well-trained radiation oncologist. Dose distribution was optimized using 180-deg. and 270-deg. two fields in passive scattering proton therapy. Well commissioned Simplified Monte Carlo algorithm was used as dose calculation engine. Daily consecutive CT image datasets was acquired by an in-room CT (Toshiba Aquilion LB). In our in-house program, two image registrations for bone and tumor were performed to shift the isocenter using treatment CT image dataset. Subsequently, dose recalculation was performed after the shift of the isocenter. When the dose distribution after the tumor registration exhibits change of dosimetric parameter of CTV D90% compared to the initial plan, an additional process of was performed that the range shifter thickness was optimized. Dose distribution with CTV D90% for the bone registration, the tumor registration only and adaptive plan with the tumor registration was compared to the initial plan. Results: In the bone registration, tumor dose coverage was decreased by 16% on average (Maximum: 56%). The tumor registration shows better coverage than the bone registration, however the coverage was also decreased by 9% (Maximum: 22%) The adaptive plan shows similar dose coverage of the tumor (Average: 2%, Maximum: 7%). Conclusion: There is a high possibility that only image registration for bone and tumor may reduce tumor coverage. Thus, our proposed methodology of image guidance and adaptive planning using the range adaptation after tumor registration would be effective for proton therapy. This research is partially supported

  5. Modern Radiation Therapy for Extranodal Lymphomas: Field and Dose Guidelines From the International Lymphoma Radiation Oncology Group

    Energy Technology Data Exchange (ETDEWEB)

    Yahalom, Joachim, E-mail: yahalomj@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Illidge, Tim [Institute of Cancer Sciences, University of Manchester, Manchester Academic Health Sciences Centre, The Christie National Health Service Foundation Trust, Manchester (United Kingdom); Specht, Lena [Department of Oncology and Hematology, Rigshospitalet, University of Copenhagen, Copenhagen (Denmark); Hoppe, Richard T. [Department of Radiation Oncology, Stanford University, Palo Alto, California (United States); Li, Ye-Xiong [Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Tsang, Richard [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Wirth, Andrew [Division of Radiation Oncology, Peter MacCallum Cancer Institute, St. Andrews Place, East Melbourne (Australia)

    2015-05-01

    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, involving any organ in the body and the spectrum of histological sub-types, poses a challenge both for routine clinical care and for the conduct of prospective and retrospective studies. This has led to uncertainty and lack of consistency in RT approaches between centers and clinicians. Thus far 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 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 adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other treatment modalities that may be have been used before RT.

  6. Intraluminal radiation therapy per endoprosthesis: A case study

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, L.A.

    Palliation of cholangeocarcinomas has been achieved by radiation delivered to the bile duct via endoprothesis. This case study supports and extends the works of others by describing the endoscopic techniques involved in the implantation of iridium seeds within a nasobiliary catheter. The case presented demonstrates endoscopic radiation treatment with no systemic radiation effects in a patient whose life extension was 19 months.

  7. A general hybrid