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Sample records for adaptive radiation therapy

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

    OpenAIRE

    Schoot, van der, A.

    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 reduce radiation-induced toxicities. First, the clinically implemented adaptive strategy was described and the dosimetric consequences of this adaptive strategy compared to conventional non-adaptive rad...

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

    NARCIS (Netherlands)

    A.J.A.J. van de Schoot

    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 reduc

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

    International Nuclear Information System (INIS)

    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. Auto-propagation of contours for adaptive prostate radiation therapy

    International Nuclear Information System (INIS)

    The purpose of this work is to develop an effective technique to automatically propagate contours from planning CT to cone beam CT (CBCT) to facilitate CBCT-guided prostate adaptive radiation therapy. Different from other disease sites, such as the lungs, the contour mapping here is complicated by two factors: (i) the physical one-to-one correspondence may not exist due to the insertion or removal of some image contents within the region of interest (ROI); and (ii) reduced contrast to noise ratio of the CBCT images due to increased scatter. To overcome these issues, we investigate a strategy of excluding the regions with variable contents by a careful design of a narrow shell signifying the contour of an ROI. For rectum, for example, a narrow shell with the delineated contours as its interior surface was constructed to avoid the adverse influence of the day-to-day content change inside the rectum on the contour mapping. The corresponding contours in the CBCT were found by warping the narrow shell through the use of BSpline deformable model. Both digital phantom experiments and clinical case testing were carried out to validate the proposed ROI mapping method. It was found that the approach was able to reliably warp the constructed narrow band with an accuracy better than 1.3 mm. For all five clinical cases enrolled in this study, the method yielded satisfactory results even when there were significant rectal content changes between the planning CT and CBCT scans. The overlapped area of the auto-mapped contours over 90% to the manually drawn contours is readily achievable. The proposed approach permits us to take advantage of the regional calculation algorithm yet avoiding the nuisance of rectum/bladder filling and provide a useful tool for adaptive radiotherapy of prostate in the future

  6. Adaptive Radiation Therapy for Postprostatectomy Patients Using Real-Time Electromagnetic Target Motion Tracking During External Beam Radiation Therapy

    International Nuclear Information System (INIS)

    Purpose: 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. Methods and Materials: 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. Results: 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. Conclusion: 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

  7. Adaptive Radiation Therapy for Postprostatectomy Patients Using Real-Time Electromagnetic Target Motion Tracking During External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Mingyao [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States); Bharat, Shyam [Philips Research North America, Briarcliff Manor, New York (United States); Michalski, Jeff M.; Gay, Hiram A. [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States); Hou, Wei-Hsien [St Louis University School of Medicine, St Louis, Missouri (United States); Parikh, Parag J., E-mail: pparikh@radonc.wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States)

    2013-03-15

    Purpose: 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. Methods and Materials: 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 (D{sub min}) with the planned D{sub min} to the CTV. Treatments were considered adequate if the delivered CTV D{sub min} is at least 95% of the planned CTV D{sub min}. Results: 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. Conclusion: 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.

  8. Androgen Induces Adaptation to Oxidative Stress in Prostate Cancer: Implications for Treatment with Radiation Therapy

    Directory of Open Access Journals (Sweden)

    Jehonathan H. Pinthus

    2007-01-01

    Full Text Available Radiation therapy is a standard treatment for prostate cancer (PC. The postulated mechanism of action for radiation therapy is the generation of reactive oxygen species (ROS. Adjuvant androgen deprivation (AD therapy has been shown to confer a survival advantage over radiation alone in high-risk localized PC. However, the mechanism of this interaction is unclear. We hypothesize that androgens modify the radioresponsiveness of PC through the regulation of cellular oxidative homeostasis. Using androgen receptor (AR+ 22rv1 and AR− PC3 human PC cell lines, we demonstrated that testosterone increased basal reactive oxygen species (bROS levels, resulting in dose-dependent activation of phospho-p38 and pAKT, increased expression of clusterin, catalase, manganese superoxide dismutase. Similar data were obtained in three human PC xenografts; WISH-PC14, WISH-PC23, CWR22, growing in testosterone-supplemented or castrated SCID mice. These effects were reversible through AD or through incubation with a reducing agent. Moreover, testosterone increased the activity of catalase, superoxide dismutases, glutathione reductase. Consequently, AD significantly facilitated the response of AR+ cells to oxidative stress challenge. Thus, testosterone induces a preset cellular adaptation to radiation through the generation of elevated bROS, which is modified by AD. These findings provide a rational for combined hormonal and radiation therapy for localized PC.

  9. Evaluation of Online/Offline Image Guidance/Adaptation Approaches for Prostate Cancer Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Qin, An [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan (United States); Sun, Ying [Department of Radiotherapy, Cancer Center, Sun Yat-sen University, Guangzhou (China); Liang, Jian [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan (United States); Yan, Di, E-mail: dyan@beaumont.edu [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan (United States)

    2015-04-01

    Purpose: To evaluate online/offline image-guided/adaptive treatment techniques for prostate cancer radiation therapy with daily cone-beam CT (CBCT) imaging. Methods and Materials: Three treatment techniques were evaluated retrospectively using daily pre- and posttreatment CBCT images on 22 prostate cancer patients. Prostate, seminal vesicles (SV), rectal wall, and bladder were delineated on all CBCT images. For each patient, a pretreatment intensity modulated radiation therapy plan with clinical target volume (CTV) = prostate + SV and planning target volume (PTV) = CTV + 3 mm was created. The 3 treatment techniques were as follows: (1) Daily Correction: The pretreatment intensity modulated radiation therapy plan was delivered after online CBCT imaging, and position correction; (2) Online Planning: Daily online inverse plans with 3-mm CTV-to-PTV margin were created using online CBCT images, and delivered; and (3) Hybrid Adaption: Daily Correction plus an offline adaptive inverse planning performed after the first week of treatment. The adaptive plan was delivered for all remaining 15 fractions. Treatment dose for each technique was constructed using the daily posttreatment CBCT images via deformable image registration. Evaluation was performed using treatment dose distribution in target and critical organs. Results: Treatment equivalent uniform dose (EUD) for the CTV was within [85.6%, 100.8%] of the pretreatment planned target EUD for Daily Correction; [98.7%, 103.0%] for Online Planning; and [99.2%, 103.4%] for Hybrid Adaptation. Eighteen percent of the 22 patients in Daily Correction had a target dose deficiency >5%. For rectal wall, the mean ± SD of the normalized EUD was 102.6% ± 2.7% for Daily Correction, 99.9% ± 2.5% for Online Planning, and 100.6% ± 2.1% for Hybrid Adaptation. The mean ± SD of the normalized bladder EUD was 108.7% ± 8.2% for Daily Correction, 92.7% ± 8.6% for Online Planning, and 89.4% ± 10.8% for Hybrid

  10. Radiation Therapy

    Science.gov (United States)

    ... therapy. At this time, you will have a physical exam , talk about your medical history , and maybe have imaging tests . Your doctor or nurse will discuss external beam radiation therapy, its benefits and side effects, and ways you can care ...

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

    International Nuclear Information System (INIS)

    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. 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

  13. 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...

  14. Replanning Criteria and Timing Definition for Parotid Protection-Based Adaptive Radiation Therapy in Nasopharyngeal Carcinoma

    Science.gov (United States)

    Yao, Wei-Rong; Xu, Shou-Ping; Liu, Bo; Cao, Xiu-Tang; Ren, Gang; Du, Lei; Zhou, Fu-Gen; Feng, Lin-Chun; Qu, Bao-Lin; Xie, Chuan-Bin; Ma, Lin

    2015-01-01

    The goal of this study was to evaluate real-time volumetric and dosimetric changes of the parotid gland so as to determine replanning criteria and timing for parotid protection-based adaptive radiation therapy in nasopharyngeal carcinoma. Fifty NPC patients were treated with helical tomotherapy; volumetric and dosimetric (Dmean, V1, and D50) changes of the parotid gland at the 1st, 6th, 11th, 16th, 21st, 26th, 31st, and 33rd fractions were evaluated. The clinical parameters affecting these changes were studied by analyses of variance methods for repeated measures. Factors influencing the actual parotid dose were analyzed by a multivariate logistic regression model. The cut-off values predicting parotid overdose were developed from receiver operating characteristic curves and judged by combining them with a diagnostic test consistency check. The median absolute value and percentage of parotid volume reduction were 19.51 cm3 and 35%, respectively. The interweekly parotid volume varied significantly (p < 0.05). The parotid Dmean, V1, and D50 increased by 22.13%, 39.42%, and 48.45%, respectively. The actual parotid dose increased by an average of 11.38% at the end of radiation therapy. Initial parotid volume, initial parotid Dmean, and weight loss rate are valuable indicators for parotid protection-based replanning. PMID:26793717

  15. Replanning Criteria and Timing Definition for Parotid Protection-Based Adaptive Radiation Therapy in Nasopharyngeal Carcinoma

    Directory of Open Access Journals (Sweden)

    Wei-Rong Yao

    2015-01-01

    Full Text Available The goal of this study was to evaluate real-time volumetric and dosimetric changes of the parotid gland so as to determine replanning criteria and timing for parotid protection-based adaptive radiation therapy in nasopharyngeal carcinoma. Fifty NPC patients were treated with helical tomotherapy; volumetric and dosimetric (Dmean, V1, and D50 changes of the parotid gland at the 1st, 6th, 11th, 16th, 21st, 26th, 31st, and 33rd fractions were evaluated. The clinical parameters affecting these changes were studied by analyses of variance methods for repeated measures. Factors influencing the actual parotid dose were analyzed by a multivariate logistic regression model. The cut-off values predicting parotid overdose were developed from receiver operating characteristic curves and judged by combining them with a diagnostic test consistency check. The median absolute value and percentage of parotid volume reduction were 19.51 cm3 and 35%, respectively. The interweekly parotid volume varied significantly (p<0.05. The parotid Dmean, V1, and D50 increased by 22.13%, 39.42%, and 48.45%, respectively. The actual parotid dose increased by an average of 11.38% at the end of radiation therapy. Initial parotid volume, initial parotid Dmean, and weight loss rate are valuable indicators for parotid protection-based replanning.

  16. On-line re-optimization of prostate IMRT plans for adaptive radiation therapy.

    Science.gov (United States)

    Wu, Q Jackie; Thongphiew, Danthai; Wang, Zhiheng; Mathayomchan, Boonyanit; Chankong, Vira; Yoo, Sua; Lee, W Robert; Yin, Fang-Fang

    2008-02-01

    For intermediate and high risk prostate cancer, both the prostate gland and seminal vesicles are included in the clinical target volume. Internal motion patterns of these two organs vary, presenting a challenge for adaptive treatment. Adaptive techniques such as isocenter repositioning and soft tissue alignment are effective when tumor volumes only exhibit translational shift, while direct re-optimization of the intensity-modulated radiation therapy (IMRT) plan maybe more desirable when extreme deformation or differential positioning changes of the organs occur. Currently, direct re-optimization of the IMRT plan using beamlet (or fluence map) has not been reported. In this study, we report a novel on-line re-optimization technique that can accomplish plan adjustment on-line. Deformable image registration is used to provide position variation information on each voxel along the three dimensions. The original planned dose distribution is used as the 'goal' dose distribution for adaptation and to ensure planning quality. Fluence maps are re-optimized via linear programming, and a plan solution can be achieved within 2 min. The feasibility of this technique is demonstrated with a clinical case with large deformation. Such on-line ART process can be highly valuable with hypo-fractionated prostate IMRT treatment.

  17. On-line re-optimization of prostate IMRT plans for adaptive radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Q Jackie [Department of Radiation Oncology, Duke University Medical Center Durham, NC (United States); Thongphiew, Danthai [Department of Radiation Oncology, Duke University Medical Center Durham, NC (United States); Wang, Zhiheng [Department of Radiation Oncology, Duke University Medical Center Durham, NC (United States); Mathayomchan, Boonyanit [Department of Electrical Engineering and Computer Science, Case Western Reserve University Cleveland, OH (United States); Chankong, Vira [Department of Electrical Engineering and Computer Science, Case Western Reserve University Cleveland, OH (United States); Yoo, Sua [Department of Radiation Oncology, Duke University Medical Center Durham, NC (United States); Lee, W Robert [Department of Radiation Oncology, Duke University Medical Center Durham, NC (United States); Yin, Fang-Fang [Department of Radiation Oncology, Duke University Medical Center Durham, NC (United States)

    2008-02-07

    For intermediate and high risk prostate cancer, both the prostate gland and seminal vesicles are included in the clinical target volume. Internal motion patterns of these two organs vary, presenting a challenge for adaptive treatment. Adaptive techniques such as isocenter repositioning and soft tissue alignment are effective when tumor volumes only exhibit translational shift, while direct re-optimization of the intensity-modulated radiation therapy (IMRT) plan maybe more desirable when extreme deformation or differential positioning changes of the organs occur. Currently, direct re-optimization of the IMRT plan using beamlet (or fluence map) has not been reported. In this study, we report a novel on-line re-optimization technique that can accomplish plan adjustment on-line. Deformable image registration is used to provide position variation information on each voxel along the three dimensions. The original planned dose distribution is used as the 'goal' dose distribution for adaptation and to ensure planning quality. Fluence maps are re-optimized via linear programming, and a plan solution can be achieved within 2 min. The feasibility of this technique is demonstrated with a clinical case with large deformation. Such on-line ART process can be highly valuable with hypo-fractionated prostate IMRT treatment.

  18. On-line re-optimization of prostate IMRT plans for adaptive radiation therapy

    Science.gov (United States)

    Wu, Q. Jackie; Thongphiew, Danthai; Wang, Zhiheng; Mathayomchan, Boonyanit; Chankong, Vira; Yoo, Sua; Lee, W. Robert; Yin, Fang-Fang

    2008-02-01

    For intermediate and high risk prostate cancer, both the prostate gland and seminal vesicles are included in the clinical target volume. Internal motion patterns of these two organs vary, presenting a challenge for adaptive treatment. Adaptive techniques such as isocenter repositioning and soft tissue alignment are effective when tumor volumes only exhibit translational shift, while direct re-optimization of the intensity-modulated radiation therapy (IMRT) plan maybe more desirable when extreme deformation or differential positioning changes of the organs occur. Currently, direct re-optimization of the IMRT plan using beamlet (or fluence map) has not been reported. In this study, we report a novel on-line re-optimization technique that can accomplish plan adjustment on-line. Deformable image registration is used to provide position variation information on each voxel along the three dimensions. The original planned dose distribution is used as the 'goal' dose distribution for adaptation and to ensure planning quality. Fluence maps are re-optimized via linear programming, and a plan solution can be achieved within 2 min. The feasibility of this technique is demonstrated with a clinical case with large deformation. Such on-line ART process can be highly valuable with hypo-fractionated prostate IMRT treatment. Abstract and preliminary data presented at 49th AAPM Annual Meeting, Minneapolis, MN, USA, July 2007.

  19. Automated registration of large deformations for adaptive radiation therapy of prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Godley, Andrew; Ahunbay, Ergun; Peng Cheng; Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, Wisconsin 53226 (United States)

    2009-04-15

    Available deformable registration methods are often inaccurate over large organ variation encountered, for example, in the rectum and bladder. The authors developed a novel approach to accurately and effectively register large deformations in the prostate region for adaptive radiation therapy. A software tool combining a fast symmetric demons algorithm and the use of masks was developed in C++ based on ITK libraries to register CT images acquired at planning and before treatment fractions. The deformation field determined was subsequently used to deform the delivered dose to match the anatomy of the planning CT. The large deformations involved required that the bladder and rectum volume be masked with uniform intensities of -1000 and 1000 HU, respectively, in both the planning and treatment CTs. The tool was tested for five prostate IGRT patients. The average rectum planning to treatment contour overlap improved from 67% to 93%, the lowest initial overlap is 43%. The average bladder overlap improved from 83% to 98%, with a lowest initial overlap of 60%. Registration regions were set to include a volume receiving 4% of the maximum dose. The average region was 320x210x63, taking approximately 9 min to register on a dual 2.8 GHz Linux system. The prostate and seminal vesicles were correctly placed even though they are not masked. The accumulated doses for multiple fractions with large deformation were computed and verified. The tool developed can effectively supply the previously delivered dose for adaptive planning to correct for interfractional changes.

  20. A framework for automated contour quality assurance in radiation therapy including adaptive techniques

    International Nuclear Information System (INIS)

    Contouring of targets and normal tissues is one of the largest sources of variability in radiation therapy treatment plans. Contours thus require a time intensive and error-prone quality assurance (QA) evaluation, limitations which also impair the facilitation of adaptive radiotherapy (ART). Here, an automated system for contour QA is developed using historical data (the ‘knowledge base’). A pilot study was performed with a knowledge base derived from 9 contours each from 29 head-and-neck treatment plans. Size, shape, relative position, and other clinically-relevant metrics and heuristically derived rules are determined. Metrics are extracted from input patient data and compared against rules determined from the knowledge base; a computer-learning component allows metrics to evolve with more input data, including patient specific data for ART. Nine additional plans containing 42 unique contouring errors were analyzed. 40/42 errors were detected as were 9 false positives. The results of this study imply knowledge-based contour QA could potentially enhance the safety and effectiveness of RT treatment plans as well as increase the efficiency of the treatment planning process, reducing labor and the cost of therapy for patients. (paper)

  1. Deformable image registration of CT and truncated cone-beam CT for adaptive radiation therapy

    Science.gov (United States)

    Zhen, Xin; Yan, Hao; Zhou, Linghong; Jia, Xun; Jiang, Steve B.

    2013-11-01

    Truncation of a cone-beam computed tomography (CBCT) image, mainly caused by the limited field of view (FOV) of CBCT imaging, poses challenges to the problem of deformable image registration (DIR) between computed tomography (CT) and CBCT images in adaptive radiation therapy (ART). The missing information outside the CBCT FOV usually causes incorrect deformations when a conventional DIR algorithm is utilized, which may introduce significant errors in subsequent operations such as dose calculation. In this paper, based on the observation that the missing information in the CBCT image domain does exist in the projection image domain, we propose to solve this problem by developing a hybrid deformation/reconstruction algorithm. As opposed to deforming the CT image to match the truncated CBCT image, the CT image is deformed such that its projections match all the corresponding projection images for the CBCT image. An iterative forward-backward projection algorithm is developed. Six head-and-neck cancer patient cases are used to evaluate our algorithm, five with simulated truncation and one with real truncation. It is found that our method can accurately register the CT image to the truncated CBCT image and is robust against image truncation when the portion of the truncated image is less than 40% of the total image. Part of this work was presented at the 54th AAPM Annual Meeting (Charlotte, NC, USA, 29 July-2 August 2012).

  2. Using patient-specific phantoms to evaluate deformable image registration algorithms for adaptive radiation therapy.

    Science.gov (United States)

    Stanley, Nick; Glide-Hurst, Carri; Kim, Jinkoo; Adams, Jeffrey; Li, Shunshan; Wen, Ning; Chetty, Indrin J; Zhong, Hualiang

    2013-11-04

    DIR algorithms need to be verified for each registration instance when implementing adaptive radiation therapy.

  3. Feasibility of breathing-adapted PET/CT imaging for radiation therapy of Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Aznar, M C; Andersen, Flemming; Berthelsen, A K;

    2011-01-01

    Aim: Respiration can induce artifacts in positron emission tomography (PET)/computed tomography (CT) images leading to uncertainties in tumour volume, location and uptake quantification. Respiratory gating for PET images is now established but is not directly translatable to a radiotherapy setup....... in PET/CT images. These results suggest that advanced therapies (such as SUV-based dose painting) will likely require breathing-adapted PET images and that the relevant SUV thresholds are yet to be investigated....

  4. Feasibility of breathing-adapted PET/CT imaging for radiation therapy of Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Aznar, M C; Andersen, Flemming; Berthelsen, A K;

    2011-01-01

    Aim: Respiration can induce artifacts in positron emission tomography (PET)/computed tomography (CT) images leading to uncertainties in tumour volume, location and uptake quantification. Respiratory gating for PET images is now established but is not directly translatable to a radiotherapy setup....... uptake in PET/CT images. These results suggest that advanced therapies (such as SUV-based dose painting) will likely require breathing-adapted PET images and that the relevant SUV thresholds are yet to be investigated....

  5. Radiation Therapy

    Science.gov (United States)

    ... goal of causing less harm to the surrounding healthy tissue. You don't have to worry that you'll glow in the dark after radiation treatment: People who receive external radiation are not radioactive. You' ...

  6. Automatic online adaptive radiation therapy techniques for targets with significant shape change: a feasibility study.

    Science.gov (United States)

    Court, Laurence E; Tishler, Roy B; Petit, Joshua; Cormack, Robert; Chin, Lee

    2006-05-21

    This work looks at the feasibility of an online adaptive radiation therapy concept that would detect the daily position and shape of the patient, and would then correct the daily treatment to account for any changes compared with planning position. In particular, it looks at the possibility of developing algorithms to correct for large complicated shape change. For co-planar beams, the dose in an axial plane is approximately associated with the positions of a single multi-leaf collimator (MLC) pair. We start with a primary plan, and automatically generate several secondary plans with gantry angles offset by regular increments. MLC sequences for each plan are calculated keeping monitor units (MUs) and number of segments constant for a given beam (fluences are different). Bulk registration (3D) of planning and daily CT images gives global shifts. Slice-by-slice (2D) registration gives local shifts and rotations about the longitudinal axis for each axial slice. The daily MLC sequence is then created for each axial slice/MLC leaf pair combination, by taking the MLC positions from the pre-calculated plan with the nearest rotation, and shifting using a beam's-eye-view calculation to account for local linear shifts. A planning study was carried out using two head and neck region MR images of a healthy volunteer which were contoured to simulate a base-of-tongue treatment: one with the head straight (used to simulate the planning image) and the other with the head tilted to the left (the daily image). Head and neck treatment was chosen to evaluate this technique because of its challenging nature, with varying internal and external contours, and multiple degrees of freedom. Shape change was significant: on a slice-by-slice basis, local rotations in the daily image varied from 2 to 31 degrees, and local shifts ranged from -0.2 to 0.5 cm and -0.4 to 0.0 cm in right-left and posterior-anterior directions, respectively. The adapted treatment gave reasonable target coverage (100

  7. 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.

  8. Adaptive Liver Stereotactic Body Radiation Therapy: Automated Daily Plan Reoptimization Prevents Dose Delivery Degradation Caused by Anatomy Deformations

    Energy Technology Data Exchange (ETDEWEB)

    Leinders, Suzanne M. [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Delft University of Technology, Delft (Netherlands); Breedveld, Sebastiaan; Méndez Romero, Alejandra [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Schaart, Dennis [Delft University of Technology, Delft (Netherlands); Seppenwoolde, Yvette, E-mail: y.seppenwoolde@erasmusmc.nl [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Heijmen, Ben J.M. [Erasmus Medical Center-Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2013-12-01

    Purpose: To investigate how dose distributions for liver stereotactic body radiation therapy (SBRT) can be improved by using automated, daily plan reoptimization to account for anatomy deformations, compared with setup corrections only. Methods and Materials: For 12 tumors, 3 strategies for dose delivery were simulated. In the first strategy, computed tomography scans made before each treatment fraction were used only for patient repositioning before dose delivery for correction of detected tumor setup errors. In adaptive second and third strategies, in addition to the isocenter shift, intensity modulated radiation therapy beam profiles were reoptimized or both intensity profiles and beam orientations were reoptimized, respectively. All optimizations were performed with a recently published algorithm for automated, multicriteria optimization of both beam profiles and beam angles. Results: In 6 of 12 cases, violations of organs at risk (ie, heart, stomach, kidney) constraints of 1 to 6 Gy in single fractions occurred in cases of tumor repositioning only. By using the adaptive strategies, these could be avoided (<1 Gy). For 1 case, this needed adaptation by slightly underdosing the planning target volume. For 2 cases with restricted tumor dose in the planning phase to avoid organ-at-risk constraint violations, fraction doses could be increased by 1 and 2 Gy because of more favorable anatomy. Daily reoptimization of both beam profiles and beam angles (third strategy) performed slightly better than reoptimization of profiles only, but the latter required only a few minutes of computation time, whereas full reoptimization took several hours. Conclusions: This simulation study demonstrated that replanning based on daily acquired computed tomography scans can improve liver stereotactic body radiation therapy dose delivery.

  9. Adaptive Radiation for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Daniel R. Gomez

    2011-01-01

    need to spare surrounding critical structures. Evolving radiotherapy technologies, such as four-dimensional (4D image-based motion management, daily on-board imaging and adaptive radiotherapy based on volumetric images over the course of radiotherapy, have enabled us to deliver higher dose to target while minimizing normal tissue toxicities. The image-guided radiotherapy adapted to changes of motion and anatomy has made the radiotherapy more precise and allowed ablative dose delivered to the target using novel treatment approaches such as intensity-modulated radiation therapy, stereotactic body radiation therapy, and proton therapy in lung cancer, techniques used to be considered very sensitive to motion change. Future clinical trials using real time tracking and biological adaptive radiotherapy based on functional images are proposed.

  10. Evaluation of a prototype 3D ultrasound system for multimodality imaging of cervical nodes for adaptive radiation therapy

    Science.gov (United States)

    Fraser, Danielle; Fava, Palma; Cury, Fabio; Vuong, Te; Falco, Tony; Verhaegen, Frank

    2007-03-01

    Sonography has good topographic accuracy for superficial lymph node assessment in patients with head and neck cancers. It is therefore an ideal non-invasive tool for precise inter-fraction volumetric analysis of enlarged cervical nodes. In addition, when registered with computed tomography (CT) images, ultrasound information may improve target volume delineation and facilitate image-guided adaptive radiation therapy. A feasibility study was developed to evaluate the use of a prototype ultrasound system capable of three dimensional visualization and multi-modality image fusion for cervical node geometry. A ceiling-mounted optical tracking camera recorded the position and orientation of a transducer in order to synchronize the transducer's position with respect to the room's coordinate system. Tracking systems were installed in both the CT-simulator and radiation therapy treatment rooms. Serial images were collected at the time of treatment planning and at subsequent treatment fractions. Volume reconstruction was performed by generating surfaces around contours. The quality of the spatial reconstruction and semi-automatic segmentation was highly dependent on the system's ability to track the transducer throughout each scan procedure. The ultrasound information provided enhanced soft tissue contrast and facilitated node delineation. Manual segmentation was the preferred method to contour structures due to their sonographic topography.

  11. 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.

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

    International Nuclear Information System (INIS)

    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

  13. SU-F-BRF-07: Impact of Different Patient Setup Strategies in Adaptive Radiation Therapy with Simultaneous Integrated Volume-Adapted Boost of NSCLC

    Energy Technology Data Exchange (ETDEWEB)

    Balik, S [Cleveland Clinic Foundation, Cleveland, OH (United States); Weiss, E; Sleeman, W; Wu, Y; Hugo, G [Virginia Commonwealth University, Richmond, VA (United States); Dogan, N [University of Miami, Miami, FL (United States); Fatyga, M [Mayo Clinic, AZ, Phoenix, AZ (United States)

    2014-06-15

    Purpose: To evaluate the potential impact of several setup error correction strategies on a proposed image-guided adaptive radiotherapy strategy for locally advanced lung cancer. Methods: Daily 4D cone-beam CT and weekly 4D fan-beam CT images were acquired from 9 lung cancer patients undergoing concurrent chemoradiation therapy. Initial planning CT was deformably registered to daily CBCT images to generate synthetic treatment courses. An adaptive radiation therapy course was simulated using the weekly CT images with replanning twice and a hypofractionated, simultaneous integrated boost to a total dose of 66 Gy to the original PTV and either a 66 Gy (no boost) or 82 Gy (boost) dose to the boost PTV (ITV + 3mm) in 33 fractions with IMRT or VMAT. Lymph nodes (LN) were not boosted (prescribed to 66 Gy in both plans). Synthetic images were rigidly, bony (BN) or tumor and carina (TC), registered to the corresponding plan CT, dose was computed on these from adaptive replans (PLAN) and deformably accumulated back to the original planning CT. Cumulative D98% of CTV of PT (ITV for 82Gy) and LN, and normal tissue dose changes were analyzed. Results: Two patients were removed from the study due to large registration errors. For the remaining 7 patients, D98% for CTV-PT (ITV-PT for 82 Gy) and CTV-LN was within 1 Gy of PLAN for both 66 Gy and 82 Gy plans with both setup techniques. Overall, TC based setup provided better results, especially for LN coverage (p = 0.1 for 66Gy plan and p = 0.2 for 82 Gy plan, comparison of BN and TC), though not significant. Normal tissue dose constraints violated for some patients if constraint was barely achieved in PLAN. Conclusion: The hypofractionated adaptive strategy appears to be deliverable with soft tissue alignment for the evaluated margins and planning parameters. Research was supported by NIH P01CA116602.

  14. External Radiation Therapy

    Medline Plus

    Full Text Available ... frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms of radiation for prostate ... typical treatment takes seven weeks. Gunnar Zagars, M.D.: A patient comes in every day, Monday to ...

  15. External Radiation Therapy

    Medline Plus

    Full Text Available ... the treatment that is frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms of radiation for prostate cancer. They really boil down to two different types. ...

  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. 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

  18. Radiation therapy physics

    CERN Document Server

    Hendee, William R; Hendee, Eric G

    2013-01-01

    The Third Edition of Radiation Therapy Physics addresses in concise fashion the fundamental diagnostic radiologic physics principles as well as their clinical implications. Along with coverage of the concepts and applications for the radiation treatment of cancer patients, the authors have included reviews of the most up-to-date instrumentation and critical historical links. The text includes coverage of imaging in therapy planning and surveillance, calibration protocols, and precision radiation therapy, as well as discussion of relevant regulation and compliance activities. It contains an upd

  19. Radiation Therapy (For Parents)

    Science.gov (United States)

    ... be some permanent changes to the color and elasticity of the skin. How can you help? Dress ... to Home and School Cancer Center Cancer Basics Types of Cancer Teens Get Radiation Therapy Chemotherapy Dealing ...

  20. 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.

  1. 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.

  2. Principles of radiation therapy

    International Nuclear Information System (INIS)

    This chapter reviews (a) the natural history of metastatic bone disease in general terms and as it impacts on the use of radiation as therapy; (b) the clinical and radiographic evaluations used to guide the application of irradiation; and (c) the methods, results, and toxicities of various techniques of irradiation

  3. External Radiation Therapy

    Medline Plus

    Full Text Available ... prostate or when the patient is older the treatment that is frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms ... different types. There's what we call external beam treatment, which is given from an x-ray machine, ...

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

    International Nuclear Information System (INIS)

    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. (paper)

  5. Microbeam radiation therapy

    Science.gov (United States)

    Laissue, Jean A.; Lyubimova, Nadia; Wagner, Hans-Peter; Archer, David W.; Slatkin, Daniel N.; Di Michiel, Marco; Nemoz, Christian; Renier, Michel; Brauer, Elke; Spanne, Per O.; Gebbers, Jan-Olef; Dixon, Keith; Blattmann, Hans

    1999-10-01

    The central nervous system of vertebrates, even when immature, displays extraordinary resistance to damage by microscopically narrow, multiple, parallel, planar beams of x rays. Imminently lethal gliosarcomas in the brains of mature rats can be inhibited and ablated by such microbeams with little or no harm to mature brain tissues and neurological function. Potentially palliative, conventional wide-beam radiotherapy of malignant brain tumors in human infants under three years of age is so fraught with the danger of disrupting the functional maturation of immature brain tissues around the targeted tumor that it is implemented infrequently. Other kinds of therapy for such tumors are often inadequate. We suggest that microbeam radiation therapy (MRT) might help to alleviate the situation. Wiggler-generated synchrotron x-rays were first used for experimental microplanar beam (microbeam) radiation therapy (MRT) at Brookhaven National Laboratory's National Synchrotron Light Source in the early 1990s. We now describe the progress achieved in MRT research to date using immature and adult rats irradiated at the European Synchrotron Radiation Facility in Grenoble, France, and investigated thereafter at the Institute of Pathology of the University of Bern.

  6. Principles of radiation therapy

    International Nuclear Information System (INIS)

    Radiation oncology now represents the integration of knowledge obtained over an 80-year period from the physics and biology laboratories and the medical clinic. Such integration is recent; until the supervoltage era following World War II, the chief developments in these three areas for the most part were realized independently. The physics and engineering laboratories have now developed a dependable family of sources of ionizing radiations that can be precisely directed at tumor volumes at various depths within the body. The biology laboratory has provided the basic scientific support underlying the intensive clinical experience and currently is suggesting ways of using ionizing radiations more effectively, such as modified fractionation schedules relating to cell cycle kinetics and the use of drugs and chemicals as modifiers of radiation response and normal tissue reaction. The radiation therapy clinic has provided the patient stratum on which the acute and chronic effects of irradiation have been assessed, and the patterns of treatment success and failure identified. The radiation therapist has shared with the surgeon and medical oncologist the responsibility for clarifying the natural history of a large number of human neoplasms, and through such clarifications, has developed more effective treatment strategies. Several examples of this include the improved results in the treatment of Hodgkin's disease, squamous cell carcinoma of the cervix, seminoma, and epithelial neoplasms of the upper aerodigestive tract

  7. 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...... in a cohort of 97 clinical stage I-II HL patients. METHODS AND MATERIALS: Patients were staged with positron emission tomography/computed tomography scans, treated with adriamycin, bleomycin, vinblastine, and dacarbazine chemotherapy, and given INRT (prechemotherapy involved nodes to 30 Gy, residual masses...

  8. Intracoronary radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Dae Hyuk; Oh, Seung Jun; Lee, Hee Kung; Park, Seong Wook; Hong, Myeong Ki [College of Medicine, Ulsan Univ., Seoul (Korea, Republic of); Bom, Hee Seung [College of Medicine, Chonnam National Univ., Kwangju (Korea, Republic of)

    2001-07-01

    Restenosis remains a major limitation of percutaneous coronary interventions. Numerous Studies including pharmacological approaches and new devices failed to reduce restenosis rate except coronary stenting. Since the results of BENESTENT and STRESS studies came out, coronary stenting has been the most popular interventional strategy in the various kinds of coronary stenotic lesions, although the efficacy of stending was shown only in the discrete lesion of the large coronary artery. The widespread use of coronary stending has improved the early and late outcomes after coronary intervention, but it has also led to a new and serious problem, e.g., in-stent restenosis. Intravascular radiation for prevention of restenosis is a new technology in the field of percutaneous coronary intervention. Recent animal experiments and human trials have demonstrated that local irradiation, in conjunction with coronary interventions, substantially diminished the rate of restenosis. This paper reviews basic radiation biology of intracoronary radiation and its role in the inhibition of restenosis. The current status of intracoronary radiation therapy using Re-188 liquid balloon is also discussed.

  9. Radiation Therapy for Skin Cancer

    Science.gov (United States)

    ... skin cells called melanocytes that produce skin color ( melanin ). Radiation therapy is used mostly for melanomas that ... in addition to surgery, chemotherapy or biologic therapy. Hair Epidermis Dermis Subcutaneous Hair Follicle Vein Artery © ASTRO ...

  10. Stereotactic body radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Simon S. [Univ. Hospitals Seidman Cancer Center, Cleveland, OH (United States). Dept. of Radiation Oncology; Case Western Reserve Univ., Cleveland, OH (United States). Case Comprehensive Cancer Center; Teh, Bin S. [The Methodist Hospital Cancer Center and Research Institute, Houston, TX (United States). Weill Cornell Medical College; Lu, Jiade J. [National Univ. of Singapore (Singapore). Dept. of Radiation Oncology; Schefter, Tracey E. (eds.) [Colorado Univ., Aurora, CO (United States). Dept. of Radiation Oncology

    2012-11-01

    Comprehensive an up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. Examines in detail retrospective studies and prospective clinical trials for various organ sites from around the world. Written by world-renowned experts in SBRT from North America, Asia and Europe. Stereotactic body radiation therapy (SBRT) has emerged as an innovative treatment for various primary and metastatic cancers, and the past five years have witnessed a quantum leap in its use. This book provides a comprehensive and up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. It will serve as a detailed resource for this rapidly developing treatment modality. The organ sites covered include lung, liver, spine, pancreas, prostate, adrenal, head and neck, and female reproductive tract. Retrospective studies and prospective clinical trials on SBRT for various organ sites from around the world are examined, and toxicities and normal tissue constraints are discussed. This book features unique insights from world-renowned experts in SBRT from North America, Asia, and Europe. It will be necessary reading for radiation oncologists, radiation oncology residents and fellows, medical physicists, medical physics residents, medical oncologists, surgical oncologists, and cancer scientists.

  11. 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.

  12. An Atlas-Based Electron Density Mapping Method for Magnetic Resonance Imaging (MRI)-Alone Treatment Planning and Adaptive MRI-Based Prostate Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dowling, Jason A., E-mail: jason.dowling@csiro.au [Australian e-Health Research Center, CSIRO ICT Commonwealth Scientific and Industrial Research Organisation Information and Communication Technologies Centre, Queensland (Australia); Lambert, Jonathan [Calvary Mater Newcastle Hospital, New South Wales (Australia); University of Newcastle, New South Wales (Australia); Parker, Joel [Calvary Mater Newcastle Hospital, New South Wales (Australia); Salvado, Olivier; Fripp, Jurgen [Australian e-Health Research Center, CSIRO ICT Commonwealth Scientific and Industrial Research Organisation Information and Communication Technologies Centre, Queensland (Australia); Capp, Anne; Wratten, Chris; Denham, James W.; Greer, Peter B. [Calvary Mater Newcastle Hospital, New South Wales (Australia); University of Newcastle, New South Wales (Australia)

    2012-05-01

    Purpose: Prostate radiation therapy dose planning directly on magnetic resonance imaging (MRI) scans would reduce costs and uncertainties due to multimodality image registration. Adaptive planning using a combined MRI-linear accelerator approach will also require dose calculations to be performed using MRI data. The aim of this work was to develop an atlas-based method to map realistic electron densities to MRI scans for dose calculations and digitally reconstructed radiograph (DRR) generation. Methods and Materials: Whole-pelvis MRI and CT scan data were collected from 39 prostate patients. Scans from 2 patients showed significantly different anatomy from that of the remaining patient population, and these patients were excluded. A whole-pelvis MRI atlas was generated based on the manually delineated MRI scans. In addition, a conjugate electron-density atlas was generated from the coregistered computed tomography (CT)-MRI scans. Pseudo-CT scans for each patient were automatically generated by global and nonrigid registration of the MRI atlas to the patient MRI scan, followed by application of the same transformations to the electron-density atlas. Comparisons were made between organ segmentations by using the Dice similarity coefficient (DSC) and point dose calculations for 26 patients on planning CT and pseudo-CT scans. Results: The agreement between pseudo-CT and planning CT was quantified by differences in the point dose at isocenter and distance to agreement in corresponding voxels. Dose differences were found to be less than 2%. Chi-squared values indicated that the planning CT and pseudo-CT dose distributions were equivalent. No significant differences (p > 0.9) were found between CT and pseudo-CT Hounsfield units for organs of interest. Mean {+-} standard deviation DSC scores for the atlas-based segmentation of the pelvic bones were 0.79 {+-} 0.12, 0.70 {+-} 0.14 for the prostate, 0.64 {+-} 0.16 for the bladder, and 0.63 {+-} 0.16 for the rectum

  13. An Atlas-Based Electron Density Mapping Method for Magnetic Resonance Imaging (MRI)-Alone Treatment Planning and Adaptive MRI-Based Prostate Radiation Therapy

    International Nuclear Information System (INIS)

    Purpose: Prostate radiation therapy dose planning directly on magnetic resonance imaging (MRI) scans would reduce costs and uncertainties due to multimodality image registration. Adaptive planning using a combined MRI-linear accelerator approach will also require dose calculations to be performed using MRI data. The aim of this work was to develop an atlas-based method to map realistic electron densities to MRI scans for dose calculations and digitally reconstructed radiograph (DRR) generation. Methods and Materials: Whole-pelvis MRI and CT scan data were collected from 39 prostate patients. Scans from 2 patients showed significantly different anatomy from that of the remaining patient population, and these patients were excluded. A whole-pelvis MRI atlas was generated based on the manually delineated MRI scans. In addition, a conjugate electron-density atlas was generated from the coregistered computed tomography (CT)-MRI scans. Pseudo-CT scans for each patient were automatically generated by global and nonrigid registration of the MRI atlas to the patient MRI scan, followed by application of the same transformations to the electron-density atlas. Comparisons were made between organ segmentations by using the Dice similarity coefficient (DSC) and point dose calculations for 26 patients on planning CT and pseudo-CT scans. Results: The agreement between pseudo-CT and planning CT was quantified by differences in the point dose at isocenter and distance to agreement in corresponding voxels. Dose differences were found to be less than 2%. Chi-squared values indicated that the planning CT and pseudo-CT dose distributions were equivalent. No significant differences (p > 0.9) were found between CT and pseudo-CT Hounsfield units for organs of interest. Mean ± standard deviation DSC scores for the atlas-based segmentation of the pelvic bones were 0.79 ± 0.12, 0.70 ± 0.14 for the prostate, 0.64 ± 0.16 for the bladder, and 0.63 ± 0.16 for the rectum. Conclusions: The

  14. The Impact of the Myeloid Response to Radiation Therapy

    Directory of Open Access Journals (Sweden)

    Michael J. Gough

    2013-01-01

    Full Text Available Radiation therapy is showing potential as a partner for immunotherapies in preclinical cancer models and early clinical studies. As has been discussed elsewhere, radiation provides debulking, antigen and adjuvant release, and inflammatory targeting of effector cells to the treatment site, thereby assisting multiple critical checkpoints in antitumor adaptive immunity. Adaptive immunity is terminated by inflammatory resolution, an active process which ensures that inflammatory damage is repaired and tissue function is restored. We discuss how radiation therapy similarly triggers inflammation followed by repair, the consequences to adaptive immune responses in the treatment site, and how the myeloid response to radiation may impact immunotherapies designed to improve control of residual cancer cells.

  15. 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.

    2013-06-01

    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

  16. 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

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

    International Nuclear Information System (INIS)

    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

  18. External Radiation Therapy

    Medline Plus

    Full Text Available ... D.: There are different forms of radiation for prostate cancer. They really boil down to two different types. There's what we call external beam treatment, which is given from an x-ray ... the prostate. [beeping] Narrator: The more common form of radiation ...

  19. External Radiation Therapy

    Medline Plus

    Full Text Available ... the cancer is not completely contained in the prostate or when the patient is older the treatment ... D.: There are different forms of radiation for prostate cancer. They really boil down to two different ...

  20. Deformable Image Registration for Adaptive Radiation Therapy of Head and Neck Cancer: Accuracy and Precision in the Presence of Tumor Changes

    Energy Technology Data Exchange (ETDEWEB)

    Mencarelli, Angelo, E-mail: a.mencarelli@nki.nl [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Kranen, Simon Robert van; Hamming-Vrieze, Olga; Beek, Suzanne van [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Nico Rasch, Coenraad Robert [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands); Department of Radiation Oncology, Amsterdam Medical Centre, Amsterdam (Netherlands); Herk, Marcel van; Sonke, Jan-Jakob [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam (Netherlands)

    2014-11-01

    Purpose: To compare deformable image registration (DIR) accuracy and precision for normal and tumor tissues in head and neck cancer patients during the course of radiation therapy (RT). Methods and Materials: Thirteen patients with oropharyngeal tumors, who underwent submucosal implantation of small gold markers (average 6, range 4-10) around the tumor and were treated with RT were retrospectively selected. Two observers identified 15 anatomical features (landmarks) representative of normal tissues in the planning computed tomography (pCT) scan and in weekly cone beam CTs (CBCTs). Gold markers were digitally removed after semiautomatic identification in pCTs and CBCTs. Subsequently, landmarks and gold markers on pCT were propagated to CBCTs, using a b-spline-based DIR and, for comparison, rigid registration (RR). To account for observer variability, the pair-wise difference analysis of variance method was applied. DIR accuracy (systematic error) and precision (random error) for landmarks and gold markers were quantified. Time trend of the precisions for RR and DIR over the weekly CBCTs were evaluated. Results: DIR accuracies were submillimeter and similar for normal and tumor tissue. DIR precision (1 SD) on the other hand was significantly different (P<.01), with 2.2 mm vector length in normal tissue versus 3.3 mm in tumor tissue. No significant time trend in DIR precision was found for normal tissue, whereas in tumor, DIR precision was significantly (P<.009) degraded during the course of treatment by 0.21 mm/week. Conclusions: DIR for tumor registration proved to be less precise than that for normal tissues due to limited contrast and complex non-elastic tumor response. Caution should therefore be exercised when applying DIR for tumor changes in adaptive procedures.

  1. Real-time fast inverse dose optimization for image guided adaptive radiation therapy-Enhancements to fast inverse dose optimization (FIDO)

    Science.gov (United States)

    Goldman, S. P.; Turnbull, D.; Johnson, C.; Chen, J. Z.; Battista, J. J.

    2009-05-01

    A fast, accurate and stable optimization algorithm is very important for inverse planning of intensity-modulated radiation therapy (IMRT), and for implementing dose-adaptive radiotherapy in the future. Conventional numerical search algorithms with positive beam weight constraints generally require numerous iterations and may produce suboptimal dose results due to trapping in local minima regions of the objective function landscape. A direct solution of the inverse problem using conventional quadratic objective functions without positive beam constraints is more efficient but it will result in unrealistic negative beam weights. We review here a direct solution of the inverse problem that is efficient and does not yield unphysical negative beam weights. In fast inverse dose optimization (FIDO) method the objective function for the optimization of a large number of beamlets is reformulated such that the optimization problem is reducible to a linear set of equations. The optimal set of intensities is then found through a matrix inversion, and negative beamlet intensities are avoided without the need for externally imposed ad hoc conditions. In its original version [S. P. Goldman, J. Z. Chen, and J. J. Battista, in Proceedings of the XIVth International Conference on the Use of Computers in Radiation Therapy, 2004, pp. 112-115; S. P. Goldman, J. Z. Chen, and J. J. Battista, Med. Phys. 32, 3007 (2005)], FIDO was tested on single two-dimensional computed tomography (CT) slices with sharp KERMA beams without scatter, in order to establish a proof of concept which demonstrated that FIDO could be a viable method for the optimization of cancer treatment plans. In this paper we introduce the latest advancements in FIDO that now include not only its application to three-dimensional volumes irradiated by beams with full scatter but include as well a complete implementation of clinical dose-volume constraints including maximum and minimum dose as well as equivalent uniform dose

  2. SU-E-J-179: Assessment of Tumor Volume Change and Movement During Stereotactic Body Radiotherapy (SBRT) for Lung Cancer: Is Adaptive Radiation Therapy (ART) Necessary?

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C; Lee, C [Asan Medical Center, Seoul (Korea, Republic of)

    2015-06-15

    Purpose: Delineation of gross tumor volumes (GTVs) is important for stereotactic body radiotherapy (SBRT). However, tumor volume changes during treatment response. Here, we have investigated tumor volume changes and movement during SBRT for lung cancer, as a means of examining the need for adaptive radiation therapy (ART). Methods: Fifteen tumors in 15 patients with lung cancer were treated with SBRT (total dose: 60 Gy in 4 fractions). GTVs were obtained from cone-beam computed tomography scans (CBCT1–4) taken before each of the 4 fractions was administered. GTVs were delineated and measured by radiation oncologists using a treatment planning system. Variance in the tumor position was assessed between the planning CT and the CBCT images. To investigate the dosimetric effects of tumor volume changes, planning CT and CBCT4 treatment plans were compared using the conformity index (CI), homogeneity index (HI), and Paddick’s index (PCI). Results: The GTV on CBCT1 was employed as a baseline for comparisons. GTV had decreased by a mean of 20.4% (range: 0.7% to 47.2%) on CBCT4. Most patients had smaller GTVs on CBCT4 than on CBCT1. The interfractional shifts of the tumor position between the planning CT and CBCT1–4 were as follows: right-left, −0.4 to 1.3 mm; anterior-posterior, −0.8 to 0.5 mm; and superiorinferior, −0.9 to 1.1 mm. Indices for plans from the planning CT and CBCT4 were as follows: CI = 0.94±0.02 and 1.11±0.03; HI= 1.1±0.02 and 1.10±0.03; and PCI = 1.35±0.16 and 1.11±0.02, respectively. Conclusion: CI, HI, and PCI did not differ between the planning CT and CBCTs. However, daily CBCT revealed a significant decrease in the GTV during lung SBRT. Furthermore, there was an obvious interfractional shift in tumor position. Using ART could potentially lead to a reduced GTV margin and improved regional tumor control for lung cancer patients with significantly decreased GTV.

  3. SU-E-J-179: Assessment of Tumor Volume Change and Movement During Stereotactic Body Radiotherapy (SBRT) for Lung Cancer: Is Adaptive Radiation Therapy (ART) Necessary?

    International Nuclear Information System (INIS)

    Purpose: Delineation of gross tumor volumes (GTVs) is important for stereotactic body radiotherapy (SBRT). However, tumor volume changes during treatment response. Here, we have investigated tumor volume changes and movement during SBRT for lung cancer, as a means of examining the need for adaptive radiation therapy (ART). Methods: Fifteen tumors in 15 patients with lung cancer were treated with SBRT (total dose: 60 Gy in 4 fractions). GTVs were obtained from cone-beam computed tomography scans (CBCT1–4) taken before each of the 4 fractions was administered. GTVs were delineated and measured by radiation oncologists using a treatment planning system. Variance in the tumor position was assessed between the planning CT and the CBCT images. To investigate the dosimetric effects of tumor volume changes, planning CT and CBCT4 treatment plans were compared using the conformity index (CI), homogeneity index (HI), and Paddick’s index (PCI). Results: The GTV on CBCT1 was employed as a baseline for comparisons. GTV had decreased by a mean of 20.4% (range: 0.7% to 47.2%) on CBCT4. Most patients had smaller GTVs on CBCT4 than on CBCT1. The interfractional shifts of the tumor position between the planning CT and CBCT1–4 were as follows: right-left, −0.4 to 1.3 mm; anterior-posterior, −0.8 to 0.5 mm; and superiorinferior, −0.9 to 1.1 mm. Indices for plans from the planning CT and CBCT4 were as follows: CI = 0.94±0.02 and 1.11±0.03; HI= 1.1±0.02 and 1.10±0.03; and PCI = 1.35±0.16 and 1.11±0.02, respectively. Conclusion: CI, HI, and PCI did not differ between the planning CT and CBCTs. However, daily CBCT revealed a significant decrease in the GTV during lung SBRT. Furthermore, there was an obvious interfractional shift in tumor position. Using ART could potentially lead to a reduced GTV margin and improved regional tumor control for lung cancer patients with significantly decreased GTV

  4. Radiation Therapy for Cancer

    Science.gov (United States)

    ... Cancers by Body Location Childhood Cancers Adolescent & Young Adult Cancers Metastatic Cancer Recurrent Cancer Research NCI’s Role in ... the affected area). Damage to the bowels, causing diarrhea and ... a second cancer caused by radiation exposure. Second cancers that develop ...

  5. External Radiation Therapy

    Medline Plus

    Full Text Available Narrator: When the cancer is not completely contained in the prostate or when the patient is older the treatment that is frequently used ... There are different forms of radiation for prostate cancer. They really boil down to two different types. ...

  6. 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.

  7. Khan's the physics of radiation therapy

    CERN Document Server

    Khan, Faiz M

    2014-01-01

    Expand your understanding of the physics and practical clinical applications of advanced radiation therapy technologies with Khan's The Physics of Radiation Therapy, 5th edition, the book that set the standard in the field. This classic full-color text helps the entire radiation therapy team-radiation oncologists, medical physicists, dosimetrists, and radiation therapists-develop a thorough understanding of 3D conformal radiotherapy (3D-CRT), stereotactic radiosurgery (SRS), high dose-rate remote afterloaders (HDR), intensity modulated radiation therapy (IMRT), image-guided radiation therapy (

  8. Radiation therapy for vestibular schwannomas.

    NARCIS (Netherlands)

    Mulder, J.J.S.; Kaanders, J.H.A.M.; Overbeeke, J.J. van; Cremers, C.W.R.J.

    2012-01-01

    PURPOSE OF REVIEW: Recently, new information on the natural course and on the results of radiation therapy of vestibular schwannomas has been published. The aim of this study is to summarize the most recent literature on the contemporary insights on the natural course and the results of the latest s

  9. Radiation therapy for endometrial carcinoma

    International Nuclear Information System (INIS)

    Although pelvic irradiation has traditionally been employed as an adjunct to surgery, the role of radiation therapy as a definitive therapeutic modality continues to be controversial. One-hundred and twenty-one patients were treated for endometrial carcinoma between 1978 and 1985 at the Medical College of Virginia Hospital. These patients were divided into three groups with respect to their treatment. Group 1 consisted of 16 patients who had preoperative radiation therapy, group 2 consisted of 77 patients who had postoperative radiation therapy, and group 3 consisted of 28 patients who had radiation therapy alone. Ninety-three percent of the patients in groups 1 and 2 and 68% of patients in group 3 had stages I and II disease. In group 3, 32% of the patients had stages III and IV disease. Two-thirds of the patients in groups 1 and 2 had moderately differentiated tumor. One-third of patients in group 3 had poorly differentiated tumor. Sixty percent of the study's population in group 2 had deep myometrial invasion. The treatment doses utilized and local failures will be presented. All of the patients have been followed for a minimum period of 2 years. The observed actuarial 5-year survival was 85%, 80%, and 53%, respectively, for groups 1, 2, and 3. The overall survival of the entire patient population was 77%. There was 1 fatality secondary to small bowel complication in group 2 and another serious complication of rectovaginal fistula in group 1 requiring colostomy. Other side effects were skin reaction, diarrhea, and cystitis, which were treated symptomatically. Analysis of the authors' institution experience with adenocarcinoma of the endometrium and its management with radiation therapy is presented. Survival is correlated with stage, grade, and depth of myometrial invasion

  10. NOTE: Cone beam computerized tomography: the effect of calibration of the Hounsfield unit number to electron density on dose calculation accuracy for adaptive radiation therapy

    Science.gov (United States)

    Hatton, Joan; McCurdy, Boyd; Greer, Peter B.

    2009-08-01

    The availability of cone beam computerized tomography (CBCT) images at the time of treatment has opened possibilities for dose calculations representing the delivered dose for adaptive radiation therapy. A significant component in the accuracy of dose calculation is the calibration of the Hounsfield unit (HU) number to electron density (ED). The aim of this work is to assess the impact of HU to ED calibration phantom insert composition and phantom volume on dose calculation accuracy for CBCT. CBCT HU to ED calibration curves for different commercial phantoms were measured and compared. The effect of the scattering volume of the phantom on the HU to ED calibration was examined as a function of phantom length and radial diameter. The resulting calibration curves were used at the treatment planning system to calculate doses for geometrically simple phantoms and a pelvic anatomical phantom to compare against measured doses. Three-dimensional dose distributions for the pelvis phantom were calculated using the HU to ED curves and compared using Chi comparisons. The HU to ED calibration curves for the commercial phantoms diverge at densities greater than that of water, depending on the elemental composition of the phantom insert. The effect of adding scatter material longitudinally, increasing the phantom length from 5 cm to 26 cm, was found to be up to 260 HU numbers for the high-density insert. The change in the HU value, by increasing the diameter of the phantom from 18 to 40 cm, was found to be up to 1200 HU for the high-density insert. The effect of phantom diameter on the HU to ED curve can lead to dose differences for 6 MV and 18 MV x-rays under bone inhomogeneities of up to 20% in extreme cases. These results show significant dosimetric differences when using a calibration phantom with materials which are not tissue equivalent. More importantly, the amount of scattering material used with the HU to ED calibration phantom has a significant effect on the dosimetric

  11. Radiation Therapy: Preventing and Managing Side Effects

    Science.gov (United States)

    ... yourself during radiation therapy Radiation therapy can damage healthy body tissues in or near the area being treated, which can cause side effects. Many people worry about this part of their cancer treatment. Before ...

  12. Radiation Therapy Alone in cT1-3N0 Non-small Cell Lung Cancer Patients Who Are Unfit for Surgical Resection or Stereotactic Radiation Therapy: Comparison of Risk-Adaptive Dose Schedules

    Science.gov (United States)

    Cho, Won Kyung; Noh, Jae Myoung; Ahn, Yong Chan; Oh, Dongryul; Pyo, Hongryull

    2016-01-01

    Purpose High dose definitive radiation therapy (RT) alone is recommended to patients with cT1-3N0 non-small cell lung cancer, who are unfit for surgery or stereotactic RT. This study was conducted to evaluate the clinical outcomes and cost-effectiveness following RT alone using two different modest hypofractionation dose schemes. Materials and Methods Between 2001 and 2014, 124 patients underwent RT alone. From 2001 till 2010, 60 Gy in 20 fractions was delivered to 79 patients (group 1). Since 2011, 60 Gy in 20 fractions (group 2, 20 patients), and 60 Gy in 15 fractions (group 3, 25 patients) were selectively chosen depending on estimated risk of esophagitis. Results At follow-up of 16.7 months, 2-year rates of local control, progression-free survival, and overall survival were 62.6%, 39.1%, and 59.1%, respectively. Overall survival was significantly better in group 3 (p=0.002). In multivariate analyses, cT3 was the most powerful adverse factor affecting clinical outcomes. Incidence and severity of radiation pneumonitis were not different among groups, while no patients developed grade 2 esophagitis in group 3 (p=0.003). Under current Korean Health Insurance Policy, RT cost per person was 22.5% less in group 3 compared with others. Conclusion The current study demonstrated that 60 Gy in 15 fractions instead of 60 Gy in 20 fractions resulted in comparable clinical outcomes with excellent safety, direct cost saving, and improved convenience to the patients with tumors located at ≥ 1.5 cm from the esophagus. PMID:26987393

  13. Personalized Radiation Therapy (PRT) for Lung Cancer.

    Science.gov (United States)

    Jin, Jian-Yue; Kong, Feng-Ming Spring

    2016-01-01

    This chapter reviews and discusses approaches and strategies of personalized radiation therapy (PRT) for lung cancers at four different levels: (1) clinically established PRT based on a patient's histology, stage, tumor volume and tumor locations; (2) personalized adaptive radiation therapy (RT) based on image response during treatment; (3) PRT based on biomarkers; (4) personalized fractionation schedule. The current RT practice for lung cancer is partially individualized according to tumor histology, stage, size/location, and combination with use of systemic therapy. During-RT PET-CT image guided adaptive treatment is being tested in a multicenter trial. Treatment response detected by the during-RT images may also provide a strategy to further personalize the remaining treatment. Research on biomarker-guided PRT is ongoing. The biomarkers include genomics, proteomics, microRNA, cytokines, metabolomics from tumor and blood samples, and radiomics from PET, CT, SPECT images. Finally, RT fractionation schedule may also be personalized to each individual patient to maximize therapeutic gain. Future PRT should be based on comprehensive considerations of knowledge acquired from all these levels, as well as consideration of the societal value such as cost and effectiveness.

  14. Radiation therapy of acromegaly.

    Science.gov (United States)

    Eastman, R C; Gorden, P; Glatstein, E; Roth, J

    1992-09-01

    Conventional megavoltage irradiation of GH-secreting tumors has predictable effects on tumor mass, GH, and pituitary function. 1. Further growth of the tumor is prevented in more than 99% of patients, with only a fraction of a percent of patients requiring subsequent surgery for tumor mass effects. 2. GH falls predictably with time. By 2 years GH falls by about 50% from the baseline level, and by 5 years by about 75% from the baseline level. The initial GH elevation and the size and erosive features of the sella turcica do not affect the percent decrease in GH from the baseline elevation. 3. With prolonged follow-up, further decrease in GH is seen at 10 and 15 years, with the fraction of surviving patients achieving GH levels less than 5 ng/mL approaching 90% after 15 years in our experience. Gender, previous surgery, and hyperprolactinemia do not seem to affect the response to treatment. Patients with initial GH greater than 100 ng/mL are significantly less likely to achieve GH values less than 5 ng/mL during long-term follow-up. 4. Hypopituitarism is a predictable outcome of treatment, is delayed, and may be more likely in patients who have had surgery prior to irradiation. There is no evidence that this complication is more common in patients with acromegaly than in patients with other pituitary adenomas receiving similar treatment. 5. Vision loss due to megavoltage irradiation--using modern techniques and limiting the total dose to 4680 rad given in 25 fractions over 35 days, with individual fractions not exceeding 180 rad--is extremely rare. The reported cases have occurred almost entirely in patients who have received larger doses or higher fractional doses. The theory that patients with acromegaly are prone to radiation-induced injury to the CNS and optic nerves and chiasm because of small vessel disease is not supported by a review of the reported cases. 6. Brain necrosis and secondary neoplasms induced by irradiation are extremely rare. 7. Although

  15. Oray surgery and radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Carl, W.

    1975-07-01

    Clinical evidence seems to indicate that careful oral surgery after radiation therapy contributes little, if anything at all, to the onset of osteoradionecrosis. In many cases the process of bone dissolution has already well progressed before teeth have to be extracted. The bone changes can be demonstrated radiographically and clinically. The teeth in the immediate area become very mobile and cause severe pain during mastication. Whether this condition could have been prevented by extractions before radiation therapy is difficult to establish. Osteoradionecrosis may be encountered in edentulous jaws. It manifests itself clinically by bone segments which break loose and penetrate through the mucosa leaving a defect which does not heal over. More research and more comparative studies are needed in this area in order to make reasonably accurate predictions.

  16. Fractionated radiation therapy after Strandqvist

    International Nuclear Information System (INIS)

    Models for predicting the total dose required to produce tolerable normal-tissue damage in radiation therapy are becoming less empirical, more realistic, and more specific for different tissue reactions. The progression is described from the 'cube root law', through STRANDQVIST'S well known graph to NSD, TDF and CRE and more recently to biologically based time factors and linear-quadratic dose-response curves. New applications of the recent approach are reviewed together with their implications for non-standard fractionation in radiation therapy. It is concluded that accelerated fractionation is an important method to be investigated, as well as hyperfractionation; and that more data are required about the proliferation rates of clonogenic cells in human tumours. (orig.)

  17. [Radiation therapy of pancreatic cancer].

    Science.gov (United States)

    Huguet, F; Mornex, F; Orthuon, A

    2016-09-01

    Currently, the use of radiation therapy for patients with pancreatic cancer is subject to discussion. In adjuvant setting, the standard treatment is 6 months of chemotherapy with gemcitabine and capecitabine. Chemoradiation (CRT) may improve the survival of patients with incompletely resected tumors (R1). This should be confirmed by a prospective trial. Neoadjuvant CRT is a promising treatment especially for patients with borderline resectable tumors. For patients with locally advanced tumors, there is no a standard. An induction chemotherapy followed by CRT for non-progressive patients reduces the rate of local relapse. Whereas in the first trials of CRT large fields were used, the treated volumes have been reduced to improve tolerance. Tumor movements induced by breathing should be taken in account. Intensity modulated radiation therapy allows a reduction of doses to the organs at risk. Whereas widely used, this technique is not recommended. PMID:27523418

  18. Radiation therapy for pleural mesothelioma

    International Nuclear Information System (INIS)

    There is clear evidence that both pleural and peritoneal malignant mesothelioma are increasing in incidence in the United States. There is a recognized long period of latency from asbestos exposure to the emergence and diagnosis of tumor. Considering the levels of asbestos utilization in the mid-20th century, we must expect that the number of cases will continue to increase until the end of this century. Evaluation of treatment options is thus a critical issue in determining treatment approaches for this disease. Recognized only recently, mesothelioma has no effective treatment, and patients are reported only anecdotally as cured. Pleural mesothelioma is the more common presentation, but even here the reports are from small, uncontrolled series. Only one study is available in which a concomitant comparison of treatment methods was carried out. Randomized clinical studies regarding treatment of pleural mesothelioma have only recently been initiated by the clinical cooperative groups. There is thus a paucity of information on treatment in general and radiation therapy specifically for malignant mesothelioma. This chapter reviews the reported experience using radiation therapy alone and combined with other modalities for the treatment of malignant pleural mesothelioma and considers the potential for improvement of the results of current methods of radiation therapy

  19. 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.

  20. Late complications of radiation therapy

    International Nuclear Information System (INIS)

    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)

  1. Practical risk management in radiation therapy

    International Nuclear Information System (INIS)

    Technology advances in radiation therapy is very remarkable. In the technological progress of radiation therapy, development of computer control technology has helped. However, there is no significant progress in the ability of human beings who is operating. In many hospitals, by the incorrect parameter setting and wrong operations at radiation treatment planning system, many incidents have been reported recently. In order to safely use invisible radiation beam for treatment, what we should be careful? In state-of-the-art radiation therapy and many technological progress, risk management should be correspond continue. I report practical risk management in radiation therapy about the technical skills, non-technical skills and the quality control. (author)

  2. Development and evaluation of a training program for therapeutic radiographers as a basis for online adaptive radiation therapy for bladder carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Foroudi, Farshad [Division of Radiation Oncology, Peter MacCallum Cancer Institute, St Andrews Place, East Melbourne, Victoria 3002 (Australia)], E-mail: farshad.foroudi@petermac.org; Wong, Jacky [Radiation Therapy Services, Peter MacCallum Cancer Center, St Andrews Place, East Melbourne, Victoria 3002 (Australia); Kron, Tomas; Roxby, Paul; Haworth, Annette [Physical Sciences, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Victoria 3002 (Australia); Bailey, Alistair [Southern Interior Cancer Centre, 399 Royal Avenue, Kelowna, British Columbia (Canada); Rolfo, Aldo; Paneghel, Andrea; Styles, Colin; Laferlita, Marcus [Radiation Therapy Services, Peter MacCallum Cancer Center, St Andrews Place, East Melbourne, Victoria 3002 (Australia); Tai, Keen Hun; Williams, Scott; Duchesne, Gillian [Division of Radiation Oncology, Peter MacCallum Cancer Institute, St Andrews Place, East Melbourne, Victoria 3002 (Australia)

    2010-02-15

    Aims: Online adaptive radiotherapy requires a new level of soft tissue anatomy recognition and decision making by therapeutic radiographers at the linear accelerator. We have developed a therapeutic radiographer training workshop encompassing soft tissue matching for an online adaptive protocol for muscle invasive bladder cancer. Our aim is to present the training program, and its evaluation which compares pre and post training staff soft tissue matching and bladder contouring using Cone Beam Computer Tomography (CBCT). Materials and Methods: Prior to commencement of an online adaptive bladder protocol, a staff training program for 33 therapeutic radiographers, with a separate ethics approved evaluation component was developed. A multidisciplinary training program over two days was carried out with a total of 11 h of training, covering imaging technology, pelvic anatomy and protocol specific decision making in both practical and theoretical sessions. The evaluation included both pre training and post training testing of staff. Results: Pre training and post training, the standard deviations in the contoured bladder between participants in left-right direction were 0.64 vs 0.59 cm, superior-inferior 0.89 vs 0.77 cm and anterior-posterior direction was 0.88 vs 0.52 cm respectively. Similarly the standard deviation in the volume contoured decreased from 40.7 cc pre training to 24.5 cc post training. Time taken in contouring was reduced by the training program (19.8 vs 17.2 min) as was the discrepancy in choice of adaptive radiotherapy plans. The greatest reduction in variations in contouring was seen in staff whose pre training had the largest deviations from the reference radiation oncologist contours. Conclusion: A formalized staff training program is feasible, well received by staff and reduces variation in organ matching and contouring. The improvement was particularly noticed in staff who pre training had larger deviations from the reference standard.

  3. Development and evaluation of a training program for therapeutic radiographers as a basis for online adaptive radiation therapy for bladder carcinoma

    International Nuclear Information System (INIS)

    Aims: Online adaptive radiotherapy requires a new level of soft tissue anatomy recognition and decision making by therapeutic radiographers at the linear accelerator. We have developed a therapeutic radiographer training workshop encompassing soft tissue matching for an online adaptive protocol for muscle invasive bladder cancer. Our aim is to present the training program, and its evaluation which compares pre and post training staff soft tissue matching and bladder contouring using Cone Beam Computer Tomography (CBCT). Materials and Methods: Prior to commencement of an online adaptive bladder protocol, a staff training program for 33 therapeutic radiographers, with a separate ethics approved evaluation component was developed. A multidisciplinary training program over two days was carried out with a total of 11 h of training, covering imaging technology, pelvic anatomy and protocol specific decision making in both practical and theoretical sessions. The evaluation included both pre training and post training testing of staff. Results: Pre training and post training, the standard deviations in the contoured bladder between participants in left-right direction were 0.64 vs 0.59 cm, superior-inferior 0.89 vs 0.77 cm and anterior-posterior direction was 0.88 vs 0.52 cm respectively. Similarly the standard deviation in the volume contoured decreased from 40.7 cc pre training to 24.5 cc post training. Time taken in contouring was reduced by the training program (19.8 vs 17.2 min) as was the discrepancy in choice of adaptive radiotherapy plans. The greatest reduction in variations in contouring was seen in staff whose pre training had the largest deviations from the reference radiation oncologist contours. Conclusion: A formalized staff training program is feasible, well received by staff and reduces variation in organ matching and contouring. The improvement was particularly noticed in staff who pre training had larger deviations from the reference standard.

  4. Radiation therapy in bronchogenic carcinoma

    International Nuclear Information System (INIS)

    Response of intrathoracic symptoms to thoracic irradiation was evaluated in 330 patients. Superior vena caval syndrome and hemoptysis showed the best response, with rates of 86% and 83%, respectively, compared to 73% for pain in the shoulder and arm and 60% for dyspnea and chest pain. Atelectasis showed re-expansion in only 23% of cases, but this figure increased to 57% for patients with oat-cell carcinoma. Vocal cord paralysis improved in only 6% of cases. Radiation therapy has a definite positive role in providing symptomatic relief for patients with carcinoma of the lung

  5. Melioidosis: reactivation during radiation therapy

    International Nuclear Information System (INIS)

    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

  6. 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.

  7. Cancer Treatment with Gene Therapy and Radiation Therapy

    OpenAIRE

    Kaliberov, Sergey A.; Buchsbaum, Donald J.

    2012-01-01

    Radiation therapy methods have evolved remarkably in recent years which have resulted in more effective local tumor control with negligible toxicity of surrounding normal tissues. However, local recurrence and distant metastasis often occur following radiation therapy mostly due to the development of radioresistance through the deregulation of the cell cycle, apoptosis, and inhibition of DNA damage repair mechanisms. Over the last decade, extensive progress in radiotherapy and gene therapy co...

  8. Radiation therapy facilities in the United States

    International Nuclear Information System (INIS)

    Purpose: About half of all cancer patients in the United States receive radiation therapy as a part of their cancer treatment. Little is known, however, about the facilities that currently deliver external beam radiation. Our goal was to construct a comprehensive database of all radiation therapy facilities in the United States that can be used for future health services research in radiation oncology. Methods and Materials: From each state's health department we obtained a list of all facilities that have a linear accelerator or provide radiation therapy. We merged these state lists with information from the American Hospital Association (AHA), as well as 2 organizations that audit the accuracy of radiation machines: the Radiologic Physics Center (RPC) and Radiation Dosimetry Services (RDS). The comprehensive database included all unique facilities listed in 1 or more of the 4 sources. Results: We identified 2,246 radiation therapy facilities operating in the United States as of 2004-2005. Of these, 448 (20%) facilities were identified through state health department records alone and were not listed in any other data source. Conclusions: Determining the location of the 2,246 radiation facilities in the United States is a first step in providing important information to radiation oncologists and policymakers concerned with access to radiation therapy services, the distribution of health care resources, and the quality of cancer care

  9. Megavoltage cone-beam CT:clinical applications for adaptive radiation therapy%兆伏级锥形束CT在自适应性放疗中的应用

    Institute of Scientific and Technical Information of China (English)

    O. Morin; H. Chen; L. Simpson; J. Pouliot; 王艳阳; M. Aubin; J. Chen; H. Chen; J-F. Aubry; A.Gillis; K. Bucci; M. Geffen; K. Kelly

    2006-01-01

    随着兆伏级锥形束CT(Megavoltage Cone-Beam CT,MV CBCT)技术的诞生,目前利用电子验证影像设备(electronic portal imaging devices,EPID)与治疗用X线束在治疗体位状态下对患者进行三维成像,并根据所获影像进行电子密度校准,已逐渐在临床上获得应用.本文首先介绍MV CBCT的一般特性,并对其在适应性放疗(Adaptive Radiation Therapy,ART)中的临床应用及发展方向进行探讨.

  10. Spinal cord biological safety of image-guided radiation therapy versus conventional radiation therapy

    Institute of Scientific and Technical Information of China (English)

    Wanlong Xu; Xilinbaoleri; Hao Liu; Ruozheng Wang; Jingping Bai

    2012-01-01

    Tumor models were simulated in purebred Beagles at the T9-10 levels of the spinal cord and treated with spinal image-guided radiation therapy or conventional radiation therapy with 50 or 70 Gy total radiation. Three months after radiation, neuronal injury at the T9-10 levels was observed, including reversible injury induced by spinal image-guided radiation therapy and apoptosis induced by conventional radiation therapy. The number of apoptotic cells and expression of the proapoptotic protein Fas were significantly reduced, but expression of the anti-apoptotic protein heat shock protein 70 was significantly increased after image-guided radiation therapy compared with the conventional method of the same radiation dose. Moreover, the spinal cord cell apoptotic index positively correlated with the ratio of Fas/heat shock protein 70. These findings indicate that 3 months of radiation therapy can induce a late response in the spinal cord to radiation therapy; image-guided radiation therapy is safer and results in less neuronal injury compared with conventional radiation therapy.

  11. 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.

  12. Study on external beam radiation therapy

    International Nuclear Information System (INIS)

    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

  13. 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.’

  14. Radiation Sensitization in Cancer Therapy.

    Science.gov (United States)

    Greenstock, Clive L.

    1981-01-01

    Discusses various aspects of radiation damage to biological material, including free radical mechanisms, radiation sensitization and protection, tumor hypoxia, mechanism of hypoxic cell radiosensitization, redox model for radiation modification, sensitizer probes of cellular radiation targets, pulse radiolysis studies of free radical kinetics,…

  15. Extramammary Paget's disease: role of radiation therapy

    International Nuclear Information System (INIS)

    Extra mammary Paget's disease (EMPD) is an uncommon premalignant skin condition that has been traditionally managed with surgery. A report of long-standing Paget's disease with transformation to invasive adenocarcinoma definitively managed with radiation therapy is presented. A review of cases of extramammary Paget's disease treated with radiation therapy is discussed. The use of radiation therapy should be considered in selected cases, as these studies demonstrate acceptable rates of local control when used as an adjunct to surgery, or as a definitive treatment modality. Copyright (2002) Blackwell Science Pty Ltd

  16. Managing the adverse effects of radiation therapy.

    Science.gov (United States)

    Berkey, Franklin J

    2010-08-15

    Nearly two thirds of patients with cancer will undergo radiation therapy as part of their treatment plan. Given the increased use of radiation therapy and the growing number of cancer survivors, family physicians will increasingly care for patients experiencing adverse effects of radiation. Selective serotonin reuptake inhibitors have been shown to significantly improve symptoms of depression in patients undergoing chemotherapy, although they have little effect on cancer-related fatigue. Radiation dermatitis is treated with topical steroids and emollient creams. Skin washing with a mild, unscented soap is acceptable. Cardiovascular disease is a well-established adverse effect in patients receiving radiation therapy, although there are no consensus recommendations for cardiovascular screening in this population. Radiation pneumonitis is treated with oral prednisone and pentoxifylline. Radiation esophagitis is treated with dietary modification, proton pump inhibitors, promotility agents, and viscous lidocaine. Radiation-induced emesis is ameliorated with 5-hydroxytryptamine3 receptor antagonists and steroids. Symptomatic treatments for chronic radiation cystitis include anticholinergic agents and phenazopyridine. Sexual dysfunction from radiation therapy includes erectile dysfunction and vaginal stenosis, which are treated with phosphodiesterase type 5 inhibitors and vaginal dilators, respectively. PMID:20704169

  17. Detoxication and antiproteolytic therapy of radiation complications

    Energy Technology Data Exchange (ETDEWEB)

    Yakhontov, N.E.; Klimov, I.A.; Lavrikova, L.P.; Martynov, A.D.; Provorova, T.P.; Serdyukov, A.S.; Shestakov, A.F. (Gor' kovskij Meditsinskij Inst. (USSR))

    1984-11-01

    49 patients with uterine cervix and ovarian carcinomas were treated with detoxication and antiproteolytic therapy of radiation-induced side-effects. The therapy permits to complete without interruption the remote gamma-therapy course and to reduce patients in-hospital periods by 10+- 1 days. The prescription of hemoder intravenous injection in a dose of 450 ml and contrical intramuscular injection (10000 AtrE) in cases of pronounced manifestations of radiation-induced side-effects (asthenia, leukopenia, enterocolitis) for 3 days should be considered an efficient therapy.

  18. 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...... 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...... 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...

  19. Comparing Postoperative Radiation Therapies for Brain Metastases

    Science.gov (United States)

    In this clinical trial, patients with one to four brain metastases who have had at least one of the metastatic tumors removed surgically will be randomly assigned to undergo whole-brain radiation therapy or stereotactic radiosurgery.

  20. 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...

  1. Nursing care update: Internal radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lowdermilk, D.L.

    1990-01-01

    Internal radiation therapy has been used in treating gynecological cancers for over 100 years. A variety of radioactive sources are currently used alone and in combination with other cancer treatments. Nurses need to be able to provide safe, comprehensive care to patients receiving internal radiation therapy while using precautions to keep the risks of exposure to a minimum. This article discusses current trends and issues related to such treatment for gynecological cancers.20 references.

  2. Nursing care update: Internal radiation therapy

    International Nuclear Information System (INIS)

    Internal radiation therapy has been used in treating gynecological cancers for over 100 years. A variety of radioactive sources are currently used alone and in combination with other cancer treatments. Nurses need to be able to provide safe, comprehensive care to patients receiving internal radiation therapy while using precautions to keep the risks of exposure to a minimum. This article discusses current trends and issues related to such treatment for gynecological cancers.20 references

  3. 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....

  4. 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.

  5. THERMOPLASTIC MATERIALS APPLICATIONS IN RADIATION THERAPY.

    Science.gov (United States)

    Munteanu, Anca; Moldoveanu, Sinziana; Manea, Elena

    2016-01-01

    This is an example of the use of thermoplastic materials in a high-tech medicine field, oncology radiation therapy, in order to produce the rigid masks for positioning and immobilization of the patient during simulation of the treatment procedure, the imaging verification of position and administration of the indicated radiation dose. Implementation of modern techniques of radiation therapy is possible only if provided with performant equipment (CT simulators, linear accelerators of high energy particles provided with multilamellar collimators and imaging verification systems) and accessories that increase the precision of the treatment (special supports for head-neck, thorax, pelvis, head-neck and thorax immobilization masks, compensating materials like bolus type material). The paper illustrates the main steps in modern radiation therapy service and argues the role of thermoplastics in reducing daily patient positioning errors during treatment. As part of quality assurance of irradiation procedure, using a rigid mask is mandatory when applying 3D conformal radiation therapy techniques, radiation therapy with intensity modulated radiation or rotational techninques.

  6. THERMOPLASTIC MATERIALS APPLICATIONS IN RADIATION THERAPY.

    Science.gov (United States)

    Munteanu, Anca; Moldoveanu, Sinziana; Manea, Elena

    2016-01-01

    This is an example of the use of thermoplastic materials in a high-tech medicine field, oncology radiation therapy, in order to produce the rigid masks for positioning and immobilization of the patient during simulation of the treatment procedure, the imaging verification of position and administration of the indicated radiation dose. Implementation of modern techniques of radiation therapy is possible only if provided with performant equipment (CT simulators, linear accelerators of high energy particles provided with multilamellar collimators and imaging verification systems) and accessories that increase the precision of the treatment (special supports for head-neck, thorax, pelvis, head-neck and thorax immobilization masks, compensating materials like bolus type material). The paper illustrates the main steps in modern radiation therapy service and argues the role of thermoplastics in reducing daily patient positioning errors during treatment. As part of quality assurance of irradiation procedure, using a rigid mask is mandatory when applying 3D conformal radiation therapy techniques, radiation therapy with intensity modulated radiation or rotational techninques. PMID:27125096

  7. Care of the patient receiving radiation therapy

    International Nuclear Information System (INIS)

    External radiation therapy, or teletherapy, is the use of ionizing radiation to destroy cancer cells. Clinical use of ionizing radiation as treatment for cancer began with the discovery of x-rays in 1895, the identification of natural radioactivity (radium) in 1896, and the first reported cure of cancer, a basal cell epithelioma, induced by radiation in 1899. Initially, radiation was administered as a single large dose and produced severe, life-threatening side effects. The basis for the use of ionizing radiation in daily increments for a period of weeks was provided by Regaud in 1922; ten years later, Coutard clinically developed the method of dose fractionation, which remains in use today. Although the use of ionizing radiation as a treatment is over eighty years old, only in recent years have advancements in its clinical application been based on research related to the biologic effect of radiation on human cells. To effectively care for the patient prior to, during, and at the completion of external radiation therapy, the nurse must know the physical and biologic basis of external radiation therapy and its clinical application

  8. Wound healing following radiation therapy: a review

    International Nuclear Information System (INIS)

    Radiation therapy may interrupt normal wound healing mechanisms. Changes in vasculature, effects on fibroblasts, and varying levels of regulatory growth factors result in the potential for altered wound healing whether radiation is given before or after surgery. Surgical factors, such as incision size, as well as radiation parameters, including dose and fractionation, are important considerations in developing overall treatment plans. Experience suggests that certain practical measures may diminish the risk of morbidity, and investigations are ongoing

  9. Evolution of radiation therapy: technology of today

    International Nuclear Information System (INIS)

    The three well established arms of treatment are surgery, radiation therapy and chemotherapy. The management of cancer is multidisciplinary; Radiation Oncologists along with Surgical Oncologists and Medical Oncologists are responsible for cancer therapeutics. They all work in close collaboration with Pathologists and Radiologists for cancer diagnosis and staging and rely on Oncology Nurses, Physiotherapists, Occupational Therapists, Nutritionists and Social Workers for optimal treatment and rehabilitation of cancer patients. Therefore cancer management is a team work for getting the best results. Radiation therapy is one of the most effective methods of treating cancer

  10. Role of radiation therapy in gastric adenocarcinoma

    Institute of Scientific and Technical Information of China (English)

    Lisa Hazard; John O'Connor; Courtney Scaife

    2006-01-01

    Outcomes in patients with gastric cancer in the United States remain disappointing, with a five-year overall survival rate of approximately 23%. Given high rates of local-regional control following surgery, a strong rationale exists for the use of adjuvant radiation therapy.Randomized trials have shown superior local control with adjuvant radiotherapy and improved overall survival with adjuvant chemoradiation. The benefit of adjuvant chemoradiation in patients who have undergone D2 lymph node dissection by an experienced surgeon is not known, and the benefit of adjuvant radiation therapy in addition to adjuvant chemotherapy continues to be defined.In unresectable disease, chemoradiation allows long-term survival in a small number of patients and provides effective palliation. Most trials show a benefit to combined modality therapy compared to chemotherapy or radiation therapy alone.The use of pre-operative, intra-operative, 3D conformal, and intensity modulated radiation therapy in gastric cancer is promising but requires further study.The current article reviews the role of radiation therapy in the treatment of resectable and unresectable gastric carcinoma, focusing on current recommendations in the United States.

  11. Modern radiation therapy for extranodal lymphomas

    DEFF Research Database (Denmark)

    Yahalom, Joachim; Illidge, Tim; Specht, Lena;

    2015-01-01

    Extranodal lymphomas (ENLs) comprise about a third of all non-Hodgkin lymphomas (NHL). Radiation therapy (RT) is frequently used as either primary therapy (particularly for indolent ENL), consolidation after systemic therapy, salvage treatment, or palliation. The wide range of presentations of ENL...... 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...

  12. Protective prostheses during radiation therapy

    International Nuclear Information System (INIS)

    Current applications and complications in the use of radiotherapy for the treatment of oral malignancy are reviewed. Prostheses are used for decreasing radiation to vital structures not involved with the lesion but located in the field of radiation. With a program of oral hygiene and proper dental care, protective prostheses can help decrease greatly the morbidity seen with existing radiotherapy regimens

  13. [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.

  14. Adaptive responses to antibody based therapy.

    Science.gov (United States)

    Rodems, Tamara S; Iida, Mari; Brand, Toni M; Pearson, Hannah E; Orbuch, Rachel A; Flanigan, Bailey G; Wheeler, Deric L

    2016-02-01

    Receptor tyrosine kinases (RTKs) represent a large class of protein kinases that span the cellular membrane. There are 58 human RTKs identified which are grouped into 20 distinct families based upon their ligand binding, sequence homology and structure. They are controlled by ligand binding which activates intrinsic tyrosine-kinase activity. This activity leads to the phosphorylation of distinct tyrosines on the cytoplasmic tail, leading to the activation of cell signaling cascades. These signaling cascades ultimately regulate cellular proliferation, apoptosis, migration, survival and homeostasis of the cell. The vast majority of RTKs have been directly tied to the etiology and progression of cancer. Thus, using antibodies to target RTKs as a cancer therapeutic strategy has been intensely pursued. Although antibodies against the epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) have shown promise in the clinical arena, the development of both intrinsic and acquired resistance to antibody-based therapies is now well appreciated. In this review we provide an overview of the RTK family, the biology of EGFR and HER2, as well as an in-depth review of the adaptive responses undertaken by cells in response to antibody based therapies directed against these receptors. A greater understanding of these mechanisms and their relevance in human models will lead to molecular insights in overcoming and circumventing resistance to antibody based therapy. PMID:26808665

  15. Research Findings on Radiation Hormesis and Radon Therapy

    International Nuclear Information System (INIS)

    Radiation hormesis research in Japan to determine the validity of Luckey's claims has revealed information on the health effects of low-level radiation. The scientific data of animal tests we obtained and successful results actually brought by radon therapy on human patients show us a clearer understanding of the health effects of low-level radiation. We obtained many animal test results and epidemiological survey data through our research activities cooperating with more than ten universities in Japan, categorized as follows: 1. suppression of cancer by enhancement of the immune system based on gene activation; 2. rejuvenation and suppression of aging by increasing cell membrane permeability and enzyme syntheses; 3. adaptive response by activation of gene expression on DNA repair and cell apoptosis; 4. pain relief and stress moderation by hormone formation in the brain and central nervous system; 5. avoidance and therapy of obstinate diseases by enhancing damage control systems and form one formation

  16. Low incidence of chest wall pain with a risk-adapted lung stereotactic body radiation therapy approach using three or five fractions based on chest wall dosimetry.

    Directory of Open Access Journals (Sweden)

    Thibaud P Coroller

    Full Text Available PURPOSE: To examine the frequency and potential of dose-volume predictors for chest wall (CW toxicity (pain and/or rib fracture for patients receiving lung stereotactic body radiotherapy (SBRT using treatment planning methods to minimize CW dose and a risk-adapted fractionation scheme. METHODS: We reviewed data from 72 treatment plans, from 69 lung SBRT patients with at least one year of follow-up or CW toxicity, who were treated at our center between 2010 and 2013. Treatment plans were optimized to reduce CW dose and patients received a risk-adapted fractionation of 18 Gy×3 fractions (54 Gy total if the CW V30 was less than 30 mL or 10-12 Gy×5 fractions (50-60 Gy total otherwise. The association between CW toxicity and patient characteristics, treatment parameters and dose metrics, including biologically equivalent dose, were analyzed using logistic regression. RESULTS: With a median follow-up of 20 months, 6 (8.3% patients developed CW pain including three (4.2% grade 1, two (2.8% grade 2 and one (1.4% grade 3. Five (6.9% patients developed rib fractures, one of which was symptomatic. No significant associations between CW toxicity and patient and dosimetric variables were identified on univariate nor multivariate analysis. CONCLUSIONS: Optimization of treatment plans to reduce CW dose and a risk-adapted fractionation strategy of three or five fractions based on the CW V30 resulted in a low incidence of CW toxicity. Under these conditions, none of the patient characteristics or dose metrics we examined appeared to be predictive of CW pain.

  17. Radiation Therapy for Cutaneous T-Cell Lymphomas.

    Science.gov (United States)

    Tandberg, Daniel J; Craciunescu, Oana; Kelsey, Chris R

    2015-10-01

    Radiation therapy is an extraordinarily effective skin-directed therapy for cutaneous T-cell lymphomas. Lymphocytes are extremely sensitive to radiation and a complete response is generally achieved even with low doses. Radiation therapy has several important roles in the management of mycosis fungoides. For the rare patient with unilesional disease, radiation therapy alone is potentially curative. For patients with more advanced cutaneous disease, radiation therapy to local lesions or to the entire skin can effectively palliate symptomatic disease and provide local disease control. Compared with other skin-directed therapies, radiation therapy is particularly advantageous because it can effectively penetrate and treat thicker plaques and tumors. PMID:26433843

  18. 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...

  19. Radiation therapy for intracranial germ cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Shingo; Hayakawa, Kazushige; Tsuchiya, Miwako; Arai, Masahiko; Kazumoto, Tomoko; Niibe, Hideo; Tamura, Masaru

    1988-04-01

    The results of radiation therapy in 31 patients with intracranial germ cell tumors have been analyzed. The five-year survival rates were 70.1 % for germinomas and 38.1 % for teratomas. Three patients with germinoma have since died of spinal seeding. The prophylactic irradiation of the spinal canal has been found effective in protecting spinal seeding, since no relapse of germinoma has been observed in cases that received entire neuraxis iradiation, whereas teratomas and marker (AFP, HCG) positive tumors did not respond favorably to radiation therapy, and the cause of death in these patients has been local failure. Long-term survivors over 3 years after radiation therapy have been determined as having a good quality of life.

  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. Building immunity to cancer with radiation therapy.

    Science.gov (United States)

    Haikerwal, Suresh J; Hagekyriakou, Jim; MacManus, Michael; Martin, Olga A; Haynes, Nicole M

    2015-11-28

    Over the last decade there has been a dramatic shift in the focus of cancer research toward understanding how the body's immune defenses can be harnessed to promote the effectiveness of cytotoxic anti-cancer therapies. The ability of ionizing radiation to elicit anti-cancer immune responses capable of controlling tumor growth has led to the emergence of promising combination-based radio-immunotherapeutic strategies for the treatment of cancer. Herein we review the immunoadjuvant properties of localized radiation therapy and discuss how technological advances in radio-oncology and developments in the field of tumor-immunotherapy have started to revolutionize the therapeutic application of radiotherapy.

  2. Radiation Therapy for Pilocytic Astrocytomas of Childhood

    International Nuclear Information System (INIS)

    Purpose: Though radiation therapy is generally considered the most effective treatment for unresectable pilocytic astrocytomas in children, there are few data to support this claim. To examine the efficacy of radiation therapy for pediatric pilocytic astrocytomas, we retrospectively reviewed the experience at our institution. Methods and Materials: Thirty-five patients 18 years old or younger with unresectable tumors and without evidence of neurofibromatosis have been treated since 1982. Patients were treated with local radiation fields to a median dose of 54 Gy. Six patients were treated with radiosurgery to a median dose of 15.5 Gy. Five patients were treated with initial chemotherapy and irradiated after progression. Results: All patients were alive after a median follow-up of 5.0 years. However, progression-free survival was 68.7%. None of 11 infratentorial tumors progressed compared with 6 of 20 supratentorial tumors. A trend toward improved progression-free survival was seen with radiosurgery (80%) compared with external beam alone (66%), but this difference did not reach statistical significance. Eight of the 9 patients progressing after therapy did so within the irradiated volume. Conclusions: Although the survival of these children is excellent, almost one third of patients have progressive disease after definitive radiotherapy. Improvements in tumor control are needed in this patient population, and the optimal therapy has not been fully defined. Prospective trials comparing initial chemotherapy to radiation therapy are warranted.

  3. Effects of radiation therapy in microvascular anastomoses

    Energy Technology Data Exchange (ETDEWEB)

    Fried, M.P.

    1985-07-01

    The otolaryngologist, as a head and neck surgeon, commonly cares for patients with upper aerodigestive tract malignancies. Therapy of these neoplasms often requires wide excision. One standard reconstructive procedure utilizes pedicled regional flaps, both dermal and myodermal which have some disadvantages. The shortcomings of these pedicled regional flaps have led to the use of the vascularized free flap in certain cases. The occasional case may lead to catastrophe if microanastomoses fail when combined with radiation. Notwithstanding, many surgical series have reported success when radiation has been given. The present investigation was undertaken to assess the effects of radiation therapy on microvascular anastomoses when radiation is administered pre- or postoperatively or when nonradiated tissue is transferred to an irradiated recipient site. These effects were observed serially in an experimental rat model using a tubed superficial epigastric flap that adequately reflected tissue viability and vascular patency. The histologic changes were then noted over a three month period after completion of both radiation and surgery. This study adds credence to the observation of the lack of deleterious effects of radiation on experimental microvascular anastomotic patency whether the radiation is given before or after surgery or if radiated tissue is approximated to nonradiated vessels.

  4. Cancer and electromagnetic radiation therapy: Quo Vadis?

    OpenAIRE

    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, adv...

  5. Malignant peritoneal mesothelioma after radiation therapy

    International Nuclear Information System (INIS)

    A 49-year-old woman developed ascites 31 years after radiation therapy for ovarian cancer and was admitted to hospital 1 year later. Diffuse infiltration of both sheets of the peritoneum was found by CT, which on histological investigation turned out to be an advanced malignant peritoneal carcinoma. When there is a history of radiation exposure, malignant peritoneal mesothelioma should be considered as the cause of ascites. (orig.)

  6. Bullous pemphigoid after radiation therapy

    International Nuclear Information System (INIS)

    Electron beam therapy applied to a lymph node metastasis from a squamous cell carcinoma was followed by the development of histologically and immunologically typical bullous pemphigoid, the lesions being initially strictly confined to the irradiation area. This observation suggests that the bullous pemphigoid antigen may be altered or unmasked by electron beam radiotherapy, leading subsequently to the production of autoantibodies. The disease in this case effectively responded to the administration of tetracycline and niacinamide, a therapeutic regimen described recently

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

    OpenAIRE

    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 har...

  8. 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

  9. Delineating organs at risk in radiation therapy

    CERN Document Server

    Cèfaro, Giampiero Ausili; Perez, Carlos A

    2014-01-01

    Defining organs at risk is a crucial task for radiation oncologists when aiming to optimize the benefit of radiation therapy, with delivery of the maximum dose to the tumor volume while sparing healthy tissues. This book will prove an invaluable guide to the delineation of organs at risk of toxicity in patients undergoing radiotherapy. The first and second sections address the anatomy of organs at risk, discuss the pathophysiology of radiation-induced damage, and present dose constraints and methods for target volume delineation. The third section is devoted to the radiological anatomy of orga

  10. Electron beams in radiation therapy

    International Nuclear Information System (INIS)

    Clinical electron beams in interaction with beam flattening and collimating devices are studied, in order to obtain the means for adequate electron therapy. A treatment planning method for arbitrary field shapes is developed that takes the properties of the collimated electron beams into account. An electron multiple-scattering model is extended to incorporate a model for the loss of electrons with depth, in order to improve electron beam dose planning. A study of ionisation measurements in two different phantom materials yields correction factors for electron beam dosimetry. (Auth.)

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

    International Nuclear Information System (INIS)

    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. 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)

  13. 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…

  14. Computer models for optimizing radiation therapy

    International Nuclear Information System (INIS)

    The aim of this contribution is to outline how methods of system analysis, control therapy and modelling can be applied to simulate normal and malignant cell growth and to optimize cancer treatment as for instance radiation therapy. Based on biological observations and cell kinetic data, several types of models have been developed describing the growth of tumor spheroids and the cell renewal of normal tissue. The irradiation model is represented by the so-called linear-quadratic model describing the survival fraction as a function of the dose. Based thereon, numerous simulation runs for different treatment schemes can be performed. Thus, it is possible to study the radiation effect on tumor and normal tissue separately. Finally, this method enables a computer-assisted recommendation for an optimal patient-specific treatment schedule prior to clinical therapy. (orig.)

  15. Combined therapy of urinary bladder radiation injury

    Energy Technology Data Exchange (ETDEWEB)

    Zaderin, V.P.; Polyanichko, M.F. (Rostovskij-na-Donu Nauchno-Issledovatel' skij Onkologicheskij Inst. (USSR))

    1982-01-01

    A scheme of therapy of radiation cystitis is suggested. It was developed on the basis of evaluation of literature and clinical data of 205 patients with radiation injury of the urinary bladder. The method is based on general and local therapy of damaged tissues by antiinflammatory drugs, anesthetics and stimulators of reparative regeneration. Severe ulcerative and incrustation cystites, refractory to conservative therapy, were treated by surgery, using antiseptics and reparation stimulators before, during and after operation. As a result, there were hardly any complications after reconstruction of the bladder with intestinal and peritoneal tissues. 104 patients (96.1%) were cured completely and ability to work was restored in 70 patients (76.9%).

  16. Analysis of image quality and dose calculation accuracy in cone beam CT acquisitions with limited projection data (half scan, half fan) with regard to usability for adaptive radiation therapy treatment planning

    International Nuclear Information System (INIS)

    Subject of this study is the question of whether cone beam CT (CBCT) images with reduced projection data are suitable for use in adaptive radiation therapy (ART) treatment planning. For this purpose image quality and dose calculation accuracy depending on imaging modality were analysed. In this context, two CBCT-methods will be indicated having reduced projection data sets: Scans acquired with 200 rotation angle in order to accelerate the CBCT process (half scan), or scans with an asymmetric cone beam and detector offset, used to enlarge the field-of-view (half fan). Methods: For three different CBCT-modes (On-Board-Imaging, Varian Medical Systems), two of them based on reduced projection data, and a conventional multidetector CT system, the main image quality parameters were studied. Treatment plans for two phantoms were transferred to all datasets and re-computed to analyse dose calculation accuracy. Furthermore imaging dose was measured for all modalities. Results: All three CBCT-modes showed similar results with regard to image quality. It was found, that a reduction in projection data does not necessarily involve deterioration in image quality parameters. For dose calculation based on CBCT images, a good agreement with the reference plan was found, with a maximum deviation for the mean dose in regions of interest of 1.1%. Imaging dose was found to be 2.5 cGy and 2.9 cGy for the large-FOV mode and the partial rotation mode, respectively, and 5.4 cGy for the 360 -full fan mode. (orig.)

  17. Comparison of particle-radiation-therapy modalities

    International Nuclear Information System (INIS)

    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, π-, 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 60Co. 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

  18. External and internal radiation therapy: Past and future directions

    Directory of Open Access Journals (Sweden)

    Sadeghi Mahdi

    2010-01-01

    Full Text Available Cancer is a leading cause of morbidity and mortality in the modern world. Treatment modalities comprise radiation therapy, surgery, chemotherapy and hormonal therapy. Radiation therapy can be performed by using external or internal radiation therapy. However, each method has its unique properties which undertakes special role in cancer treatment, this question is brought up that: For cancer treatment, whether external radiation therapy is more efficient or internal radiation therapy one? To answer this question, we need to consider principles and structure of individual methods. In this review, principles and application of each method are considered and finally these two methods are compared with each other.

  19. Stereotactic radiation therapy and radiosurgery.

    Science.gov (United States)

    Ostertag, C B

    1994-01-01

    In all stereotactic irradiation procedures, a high dose is delivered to a relatively small target volume. Whether fractionated stereotactic radiotherapy is preferable (based on a therapeutic ratio) or a radiosurgical method (aiming at the precise and complete destruction of a tissue volume) depends on the definition and composition of the target. The methodologies can be grouped in closed-skull external focussed beam stereotactic radiosurgery/radiotherapy and in stereotactic implantation/injection of radiation sources. Although originally developed to treat functional disorders of the brain, stereotactic radiosurgery has been used most successfully for over 4 decades to treat cerebral arteriovenous malformations. Complete obliteration ranges from 30 to 50% after 1 year are reported. At 2 years the results range from 72 to 90%. Clearly the outcome is influenced by patient selection. In the treatment of acoustic neurinomas follow-up data of larger series of radiosurgery show that the treatment performed under local anesthesia on an outpatient basis becomes comparable with the best microsurgery data. Using multiple isocenters and MR localization tumor growth control is achieved in more than 90% of cases, with hearing preservation of approximately 50%. Pituitary tumors with Cushing's syndrome, acromegaly, Nelson's syndrome, prolactinomas and nonsecreting adenomas have been treated with various stereotactic irradiation methods. Further refinement of both localization techniques, dose distribution and beam manipulation will make radiosurgery an attractive modality because of its noninvasive character and low morbidity. Only a small subgroup of patients with low-grade gliomas are candidates for stereotactic localized irradiation treatment, namely those with circumscribed tumors with only limited spread of tumor cells into the periphery. For this subgroup, which usually comprises not more than 25% of all low-grade gliomas, the results from interstitial radiosurgery compete

  20. Hyperbaric oxygen therapy for radiation cystitis

    Energy Technology Data Exchange (ETDEWEB)

    Gakiya, Munehisa [Okinawa Prefectural Miyako Hospital, Hirara (Japan)

    1999-08-01

    We used hyperbaric oxygen therapy (HBO) on 11 patients with radiation cystitis from 1996 to 1998. The patients aged from 46 to 78 years with a mean of 64 years underwent one or more courses of HBO consisting of 20 sessions. During the 60 min HBO patients received 100% oxygen at 2.5 absolute atmosphere pressure in the Simple Hyperbaric Chamber. Hematuria improved in all patients. Cystoscopic findings of mucosal edema, redness and capillary dilatation were improved. HBO appears to be useful for radiation cystitis. (author)

  1. 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

    The metacognitive model and therapy has proven to be a promising theory and intervention for emotional disorders in adults. The model has also received empirical support in normal and clinical child samples. The purpose of the present study was to adapt metacognitive therapy to children (MCT......-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...

  2. Lacrimal gland lymphoma: Role of radiation therapy

    OpenAIRE

    Natasha Townsend; Aruna Turaka; Smith, Mitchell R.

    2012-01-01

    Background: To report the clinical and treatment outcome of patients with lacrimal gland lymphoma (LGL) treated with radiation therapy (RT) at Fox Chase Cancer Center, Philadelphia, PA, USA. Materials and Methods: Institutional review board approved retrospective chart review of eight patients and literature review. Results: The study patients included six males and two females with a mean age of 70 years (range 58-88 years). The mean follow-up period was 23 months (range 3–74 months). Four p...

  3. Recommendation of the working group commissioned by the French nuclear safety authority on stereotactic radiation therapy

    International Nuclear Information System (INIS)

    Purpose. - At the request of the French nuclear safety authority (Autorite de Surete Nucleaire, ASN) a working party of multidisciplinary experts was initiated to elaborate a report regarding propositions for the clinical practice of stereotactic radiation therapy and the related medical physics. Material and methods. - Several stereotactic radiation therapy experts were audited by the working party, especially neurosurgeons and neuro-radiologists, as well as radiation oncologists, medical physicists and radiation technologists. An international survey was conducted looking at legal requirements and guidelines concerning stereotactic radiation therapy. A national survey was conducted in France among 29 departments performing stereotactic radiation therapy. The working party report was submitted for advice to the permanent group of medical experts of ASN. Results. - Among the 13 countries who responded, very few have legal documents. Some of them are stating that stereotactic radiation therapy must be performed in a radiotherapy department and only by well-trained professionals. Guidelines describing the role of each participant have been published in the USA. In France, stereotactic radiation therapy is performed with dedicated machines or adapted linear accelerators. In 2009, within the 29 departments, 4247 patients were treated with stereotactic radiation therapy representing 4% of the patients treated with external beam radiation therapy. Intracranial lesions were: 3383 and extracranial: 864. The working party of multidisciplinary experts made 7 recommendations. The first one saying that stereotactic radiation therapy must be considered as a radiotherapy. The permanent group of medical experts is asking to modify the 'decret du 19 mars 2007' regarding 'radiosurgery'. Conclusion. - The medical benefit of stereotactic radiation therapy is well admitted and it is an increasingly used technique. This work through practical guidelines and legal propositions intends

  4. 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

  5. Radiation therapy for unresected gastric lymphoma

    International Nuclear Information System (INIS)

    Six consecutive patients with unresected gastric lymphoma which were treated by radiation therapy between November 1976 and March 1989 were reviewed. Radiation therapy was performed using involved fields, total radiation dosages of which ranged from 25.2 to 36 Gy (mean, 29.3 Gy). Five out of the 6 patients were treated with chemotherapy combined with radiation. Regimen of the chemotherapy was CHOP (cyclophophamide, adriamycin, vincristine and prednisone) in most cases. Three out of the 6 underwent probe laparotomy, but the tumors were diagnosed as unresectable due to locally invading the adjacent structures. They were treated by chemo-radiotherapy and 2 of them are surviving as of the present study (40 and 116 months). The other 3 patients were diagnosed as with clinical stage IV disease and 2 of them were successfully treated with chemo-radiotherapy (21 and 66 months, surviving). These data suggest that unresected gastric lymphomas, which are locally advanced or stage IV disease, are treated by chemo-radiotherapy with high curability without any serious complications. (author)

  6. Chronic neuroendocrinological sequelae of radiation therapy

    International Nuclear Information System (INIS)

    A variety of neuroendocrine disturbances are observed following treatment with external radiation therapy when the hypothalamic-pituitary axis (HPA) is included in the treatment field. Radiation-induced abnormalities are generally dose dependent and may develop many years after irradiation. Growth hormone deficiency and premature sexual development can occur following doses as low as 18 Gy fractionated radiation and are the most common neuroendocrine problems noted in children. Deficiency of gonadotropins, thyroid stimulating hormone, and adrenocorticotropin are seen primarily in individuals treated with > 40 Gy HPA irradiation. Hyperprolactinemia can be seen following high-dose radiotherapy (> 40 Gy), especially among young women. Most neuroendocrine disturbances that develop as a result of HPA irradiation are treatable; patients at risk require long-term endocrine follow-up

  7. Chronic neuroendocrinological sequelae of radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sklar, C.A. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Constine, L.S. [Univ. of Rochester Medical Center, Rochester, NY (United States)

    1995-03-30

    A variety of neuroendocrine disturbances are observed following treatment with external radiation therapy when the hypothalamic-pituitary axis (HPA) is included in the treatment field. Radiation-induced abnormalities are generally dose dependent and may develop many years after irradiation. Growth hormone deficiency and premature sexual development can occur following doses as low as 18 Gy fractionated radiation and are the most common neuroendocrine problems noted in children. Deficiency of gonadotropins, thyroid stimulating hormone, and adrenocorticotropin are seen primarily in individuals treated with > 40 Gy HPA irradiation. Hyperprolactinemia can be seen following high-dose radiotherapy (>40 Gy), especially among young women. Most neuroendocrine disturbances that develop as a result of HPA irradiation are treatable; patients at risk require long-term endocrine follow-up. 23 refs., 6 figs., 2 tabs.

  8. Adaptive radiation versus 'radiation' and 'explosive diversification': why conceptual distinctions are fundamental to understanding evolution.

    Science.gov (United States)

    Givnish, Thomas J

    2015-07-01

    Adaptive radiation is the rise of a diversity of ecological roles and role-specific adaptations within a lineage. Recently, some researchers have begun to use 'adaptive radiation' or 'radiation' as synonymous with 'explosive species diversification'. This essay aims to clarify distinctions between these concepts, and the related ideas of geographic speciation, sexual selection, key innovations, key landscapes and ecological keys. Several examples are given to demonstrate that adaptive radiation and explosive diversification are not the same phenomenon, and that focusing on explosive diversification and the analysis of phylogenetic topology ignores much of the rich biology associated with adaptive radiation, and risks generating confusion about the nature of the evolutionary forces driving species diversification. Some 'radiations' involve bursts of geographic speciation or sexual selection, rather than adaptive diversification; some adaptive radiations have little or no effect on speciation, or even a negative effect. Many classic examples of 'adaptive radiation' appear to involve effects driven partly by geographic speciation, species' dispersal abilities, and the nature of extrinsic dispersal barriers; partly by sexual selection; and partly by adaptive radiation in the classical sense, including the origin of traits and invasion of adaptive zones that result in decreased diversification rates but add to overall diversity.

  9. Translation and adaptation procedures for music therapy outcome instruments

    DEFF Research Database (Denmark)

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

    2016-01-01

    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...

  10. 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.

  11. Palliative radiation therapy for multiple myeloma

    International Nuclear Information System (INIS)

    Radiation therapy is a useful palliative modality for refractory lesions of multiple myeloma. It has been reported that total doses of 10 to 20 Gy are usually adequate to obtain some degree of pain relief. However, there are many patients who need additional doses to obtain sufficient pain relief. In this study. we retrospectively analyzed the records of patients with multiple myeloma irradiated at our department, in an attempt to develop an effective treatment policy for this disease. Twenty-nine patients with 53 lesions were treated between 1968 and 1993. Total irradiation doses were 4 to 60 Gy (median 40 Gy) with daily fractions of 2 Gy or less, and 16 to 51 Gy (median 30 Gy) with daily fractions greater than 2 Gy. Evaluated were 59 symptoms, including pain (68%), neurological abnormalities (15%), and masses (28%). Symptomatic remission was obtained in 33 of 36 (92%) lesions with pain, 6 of 8 (75%) with neurological abnormalities, and 13 of 15 (87%) mass lesions. Pain was partially relieved at a median TDF of 34, and completely at a median TDF of 66 (equivalent to 40-42 Gy with daily fractions of 2 Gy). Radiation therapy is an effective and palliative treatment method for symptomatic multiple myeloma. However, the treatment seems to require higher radiation doses than those reported to obtain adequate relief of symptoms. (author)

  12. External beam radiation therapy for prostate cancer

    International Nuclear Information System (INIS)

    Purpose/Objectives: The intent of this course is to review the issues involved in the management of non-metastatic adenocarcinoma of the prostate. -- The value of pre-treatment prognostic factors including stage, grade and PSA value will be presented, and their value in determining therapeutic strategies will be discussed. -- Controversies involving the simulation process and treatment design will be presented. The value of CT scanning, Beams-Eye View, 3-D planning, intravesicle, intraurethral and rectal contrast will be presented. The significance of prostate and patient movement and strategies for dealing with them will be presented. -- The management of low stage, low to intermediate grade prostate cancer will be discussed. The dose, volume and timing of irradiation will be discussed as will the role of neo-adjuvant hormonal therapy, neutron irradiation and brachytherapy. The current status of radical prostatectomy and cryotherapy will be summarized. Treatment of locally advanced, poorly differentiated prostate cancer will be presented including a discussion of neo-adjuvant and adjuvant hormones, dose-escalation and neutron irradiation. -- Strategies for post-radiation failures will be presented including data on cryotherapy, salvage prostatectomy and hormonal therapy (immediate, delayed and/or intermittent). New areas for investigation will be reviewed. -- The management of patients post prostatectomy will be reviewed. Data on adjuvant radiation and therapeutic radiation for biochemical or clinically relapsed patients will be presented. This course hopes to present a realistic and pragmatic overview for treating patients with non-metastatic prostatic cancer

  13. Delayed radiation effect on animals: adaptive reply

    International Nuclear Information System (INIS)

    The adaptive response by micronuclei test was studied in mole-voles (Ellobius talpinus) from two populations differing in degree of radioactive contamination. It was found the significant adaptive response in animals living the left coast of the Techa River, as compared to the reference one. Some convincing evidences of the adaptive rearrangements and higher radioresistance of animals inhabiting the radiocontaminated zone during a long period and in the course of changing generations was obtained at the example of radiosensitive specie. (authors)

  14. [Radiation therapy for prostate cancer in modern era].

    Science.gov (United States)

    Nishimura, Takuya

    2016-01-01

    The purpose of this paper is to provide overview of the latest research trend on technique of radiation therapy of prostate cancer. Three-dimensional conformal radiation therapy(3D -CRT) has achieved better outcome of treatment for prostate cancer than 2-dimensional radiation therapy. Intensity-modulated radiation therapy(IMRT) is considered to be superior to 3D-CRT at certain points. Image-guided (IG) radiation therapy (IGRT), mainly IG-IMRT, is investigated what kind of influence it has on an outcome, both tumor control rate and adverse events. Particle therapy is a most ideal therapy theoretically. There is, however, few evidence which revealed that the therapy is superior to any other modalities.

  15. 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 Section 892.5300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... therapy system. (a) Identification. A medical neutron radiation therapy system is a device intended...

  16. Fine-scale recombination and adaptive radiation could be linked.

    Science.gov (United States)

    Bodilis, Josselin

    2013-09-15

    The difficult reconstruction of the evolutionary history of the major surface protein gene oprF highlighted an adaptive radiation in the Pseudomonas fluorescens group. The recent work of Hao (2013) showed that partial recombination events in oprF gene occurred specifically in a P. fluorescens lineage under ecological niche segregation. So, I suggest that identification of lineage-specific fine-scale recombination may be a way to detect putative adaptive radiation in bacteria. PMID:23774687

  17. Emerging Canadian QA standards for radiation therapy

    International Nuclear Information System (INIS)

    Full text: Canada operates a publicly funded health care system in which 70% of health care costs are paid by some level of government. Radiotherapy, indeed most cancer management, falls within the publicly funded realm of Canada's health care system. National legislation (the Canada Health Act) guarantees access to cancer services for all Canadians. However, the financial responsibility for these services is borne by the provinces. Most Canadian provinces manage the cancer management problem through central cancer agencies. In the past few decades, these provincial cancer agencies have formed the Canadian Association of Provincial Cancer Agencies (CAPCA). This association has adopted a broad mandate for cancer management in Canada (see www.capca.ca). Included in this mandate is the adoption of standards and guidelines for all aspects of cancer control. The complexity of radiation therapy has long underscored the need for cooperation at the international and national levels in defining programmes and standards. In recent decades formal quality assurance programme recommendations have emerged in the United States, Europe and Great Britain. When defining quality assurance programs, Canadian radiation treatment centres have referenced U.S. and other program standards since they have been available. Recently, under the leadership of the Canadian Association of Provincial Cancer Agencies (CAPCA), Canadian national quality assurance program recommendations are emerging. A CAPCA sponsored project to harmonize Canadian quality assurance processes has resulted in a draft document entitled 'Standards for Quality Assurance at Canadian Radiation Treatment Centres'. This document provides recommendations for the broad framework of radiation therapy quality assurance programs. In addition, detailed work is currently underway regarding equipment quality control procedures. This paper explores the historical and political landscape in which the quality assurance problem has

  18. Phylogenetic context determines the role of competition in adaptive radiation.

    Science.gov (United States)

    Tan, Jiaqi; Slattery, Matthew R; Yang, Xian; Jiang, Lin

    2016-06-29

    Understanding ecological mechanisms regulating the evolution of biodiversity is of much interest to ecologists and evolutionary biologists. Adaptive radiation constitutes an important evolutionary process that generates biodiversity. Competition has long been thought to influence adaptive radiation, but the directionality of its effect and associated mechanisms remain ambiguous. Here, we report a rigorous experimental test of the role of competition on adaptive radiation using the rapidly evolving bacterium Pseudomonas fluorescens SBW25 interacting with multiple bacterial species that differed in their phylogenetic distance to the diversifying bacterium. We showed that the inhibitive effect of competitors on the adaptive radiation of P. fluorescens decreased as their phylogenetic distance increased. To explain this phylogenetic dependency of adaptive radiation, we linked the phylogenetic distance between P. fluorescens and its competitors to their niche and competitive fitness differences. Competitive fitness differences, which showed weak phylogenetic signal, reduced P. fluorescens abundance and thus diversification, whereas phylogenetically conserved niche differences promoted diversification. These results demonstrate the context dependency of competitive effects on adaptive radiation, and highlight the importance of past evolutionary history for ongoing evolutionary processes. PMID:27335414

  19. Enzo+Moray: Radiation Hydrodynamics Adaptive Mesh Refinement Simulations with Adaptive Ray Tracing

    CERN Document Server

    Wise, John H

    2010-01-01

    We describe a photon-conserving radiative transfer algorithm, using a spatially-adaptive ray tracing scheme, and its parallel implementation into the adaptive mesh refinement (AMR) cosmological hydrodynamics code, Enzo. By coupling the solver with the energy equation and non-equilibrium chemistry network, our radiation hydrodynamics framework can be utilised to study a broad range of astrophysical problems, such as stellar and black hole (BH) feedback. Inaccuracies can arise from large timesteps and poor sampling, therefore we devised an adaptive time-stepping scheme and a fast approximation of the optically-thin radiation field with multiple sources. We test the method with several radiative transfer and radiation hydrodynamics tests that are given in Iliev et al. (2006, 2009). We further test our method with more dynamical situations, for example, the propagation of an ionisation front through a Rayleigh-Taylor instability, time-varying luminosities, and collimated radiation. The test suite also includes an...

  20. Some computer graphical user interfaces in radiation therapy

    OpenAIRE

    Chow, James C.L.

    2016-01-01

    In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in...

  1. Adaptation hypothesis of biological effectiveness of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kudritsky, Yu.K.; Georgievsky, A.B.; Karpov, V.I.

    1993-12-31

    The adoptation hypothesis of biological effectiveness of ionizing radiations is based on the recognition of the invariability of general biological laws for radiobiology and on the comprehension of life evolution regularities and axiomatic principles of environment and biota unity. The ionizing radiation factor is essential for life which could not exist beyond the radiation field. The possibility of future development of the adaptation hypothesis serves as a basis for it`s transformation into the theoretical foundation of radiobiology. This report discusses the aspects of the adaptation theory.

  2. Potential for heavy particle radiation therapy

    International Nuclear Information System (INIS)

    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 60Co 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

  3. 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.

  4. How relevant to radiation protection is the adaptive response mechanism?

    International Nuclear Information System (INIS)

    There is evidence that the phenomenon of adaptive response (AR) which results from a low dose exposure could modify the risk of a subsequent radiation exposure, and conceivably could even provide a net benefit rather than the putative radiation detriment at low doses. The AR has been widely observed in human and other mammalian cells exposed to low doses and low-dose rates. The phenomenon has been demonstrated at the level of one track per cell, the lowest insult a cell can receive. The AR to radiation has been shown to: (i) protect against the DNA damaging effects of radiation and many chemical carcinogens; (ii) increase the probability that improperly repaired cells will die by apoptosis, thereby reducing risk to the whole organism; (iii) suppress both spontaneous- and radiation-induced neoplastic transformation in vitro; and (iv) reduce life-shortening in mice that develop myeloid leukemia as a result of a radiation exposure. It remains unclear, however, if the AR will be relevant to either risk assessment or radiation protection. There is currently no evidence of AR's influence on the incidence of radiogenic cancer in vivo although recent data indicate that adapting doses could lead to reduced risk in animal or human populations. Currently the existing dose control and dose management programs attempt to limit or eliminate even very low exposures, without evidence that such an approach has economic and societal benefits. Indeed, if adaptation from exposure to low doses provides the same responses in vivo as have been shown in vitro, then the current approach to protection against low doses may be counterproductive However, the demonstrated principles of the adaptive response to radiation in vitro will not likely influence the long held current formulation of radiation protection practices until the biological action of accumulated low doses of radiation in vivo and its impact on the modulation of radiation carcinogenesis are better understood. (author)

  5. Melanomas: radiobiology and role of radiation therapy

    International Nuclear Information System (INIS)

    Purpose/Objective: This course will review the radiobiology of malignant melanoma (MM) and the clinical use of radiation therapy for metastatic melanoma and selected primary sites. The course will emphasize the scientific principles underlying the clinical treatment of MM. Introduction: The incidence of malignant melanoma has one of the fastest growth rates in the world. In 1991, there were 32,000 cases and 7,000 deaths from MM in the United States. By the year 2000, one of every 90 Americans will develop MM. Wide local excision is the treatment of choice for Stage I-II cutaneous MM. Five-year survival rates depend on (a) sex: female-63%, male-40%; (b) tumor thickness: t 4 mm-25%; (c) location: extremity-60%, trunk-41%; and (d) regional lymph node status: negative-77%, positive-31%. Despite adequate surgery, 45-50% of all MM patients will develop metastatic disease. Radiobiology: Both the multi-target model: S = 1-(1-e-D/Do)n and the linear quadratic mode: -In(S) = alpha x D + beta x D2 predict a possible benefit for high dose per fraction (> 400 cGy) radiation therapy for some MM cell lines. The extrapolation number (n) varies from 1-100 for MM compared to other mammalian cells with n=2-4. The alpha/beta ratios for a variety of MM cell lines vary from 1 to 33. Other radiobiologic factors (repair of potentially lethal damage, hypoxia, reoxygenation, and repopulation) predict a wide variety of clinical responses to different time-dose prescriptions including high dose per fraction (> 400 cGy), low dose per fraction (200-300 cGy), or b.i.d. therapy. Based on a review of the radiobiology of MM, no single therapeutic strategy emerges which could be expected to be successful for all tumors. Time-Dose Prescriptions: A review of the retrospective and prospective clinical trials evaluating various time-dose prescriptions for MM reveals: (1) MM is a radiosensitive tumor over a wide range of diverse time-dose prescriptions; and (2) The high clinical response rates to a

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

    Science.gov (United States)

    Hess, Clayton B; Thompson, Holly M; Benedict, Stanley H; Seibert, J Anthony; Wong, Kenneth; Vaughan, Andrew T; Chen, Allen M

    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

  7. Radiation therapy for carcinoma of the vulva

    International Nuclear Information System (INIS)

    Thirty-three patients suffering from squamous cell carcinoma of the vulva were treated with radiation therapy alone between 1961 and 1980 at the NIRS. The five-year survival rate and local control rate in each stage were 91 % and 36 % in T2 and 71 % and 64 % in T3, respectively. These results indicated that the early detection of recurrent tumor by close follow-up and an adequate retreatment procedure is very important for prologing survival. Late recurrence, more than five years after treatment, appeared in 30 % of the patients and this may be one of the special figures of postirradiated vulval carcinoma. The primary site was irradiated with external electron beams or radium needles, and better results were obtained with the later. Irradiation to the lymph node area in the pelvic cavity was necessary in patients with a more advanced stage of disease than T2. (author)

  8. Radiation therapy - what to ask your doctor

    Science.gov (United States)

    ... Lung cancer - small cell Metastatic brain tumor Non-Hodgkin lymphoma Prostate cancer Testicular cancer Patient Instructions Abdominal radiation - discharge Bleeding during cancer treatment Brain radiation - discharge Breast radiation - discharge Chest radiation - ...

  9. Radiation pneumonitis after stereotactic radiation therapy for lung cancer

    Institute of Scientific and Technical Information of China (English)

    Hideomi; Yamashita; Wataru; Takahashi; Akihiro; Haga; Keiichi; Nakagawa

    2014-01-01

    Stereotactic body radiation therapy(SBRT)has a locacontrol rate of 95%at 2 years for non-small cell lungcancer(NSCLC)and should improve the prognosis oinoperable patients,elderly patients,and patients withsignificant comorbidities who have early-stage NSCLCThe safety of SBRT is being confirmed in internationalmulti-institutional PhaseⅡtrials for peripheral lungcancer in both inoperable and operable patients,bureports so far have found that SBRT is a safe and effective treatment for early-stage NSCLC and early metastatic lung cancer.Radiation pneumonitis(RP)is oneof the most common toxicities of SBRT.Although mospost-treatment RP is Grade 1 or 2 and either asymptomatic or manageable,a few cases are severe,symptomatic,and there is a risk for mortality.The reportedrates of symptomatic RP after SBRT range from 9%to28%.Being able to predict the risk of RP after SBRT isextremely useful in treatment planning.A dose-effecrelationship has been demonstrated,but suggesteddose-volume factors like mean lung dose,lung V20and/or lung V2.5 differed among the reports.We foundthat patients who present with an interstitial pneumo-nitis shadow on computed tomography scan and high levels of serum Krebs von den Lungen-6 and surfactant protein D have a high rate of severe radiation pneumo-nitis after SBRT.At our institution,lung cancer patients with these risk factors have not received SBRT since 2006,and our rate of severe RP after SBRT has de-creased significantly since then.

  10. Liver cancer and selective internal radiation therapy

    International Nuclear Information System (INIS)

    Liver cancer is the biggest cancer-related killer of adults in the world. Liver cancer can be considered as two types: primary and secondary (metastatic). Selective Internal Radiation Therapy (SIRT) is a revolutionary treatment for advanced liver cancer that utilises new technologies designed to deliver radiation directly to the site of tumours. SIRT, on the other hand, involves the delivery of millions of microscopic radioactive spheres called SIR-Spheres directly to the site of the liver tumour/s, where they selectively irradiate the tumours. The anti-cancer effect is concentrated in the liver and there is little effect on cancer at other sites such as the lungs or bones. The SIR-Spheres are delivered through a catheter placed in the femoral artery of the upper thigh and threaded through the hepatic artery (the major blood vessel of the liver) to the site of the tumour. The microscopic spheres, each approximately 35 microns (the size of four red blood cells or one-third the diameter of a strand of hair), are bonded to yttrium-90 (Y-90), a pure beta emitter with a physical half-life of 64.1 hours (about 2.67 days). The microspheres are trapped in the tumour's vascular bed, where they destroy the tumour from inside. The average range of the radiation is only 2.5 mm, so it is wholly contained within the patient's body; after 14 days, only 2.5 percent of the radioactive activity remains. The microspheres are suspended in water for injection. The vials are shipped in lead shields for radiation protection. Treatment with SIR-Spheres is generally not regarded as a cure, but has been shown to shrink the cancer more than chemotherapy alone. This can increase life expectancy and improve quality of life. On occasion, patients treated with SIR-Spheres have had such marked shrinkage of the liver cancer that the cancer can be surgically removed at a later date. This has resulted in a long-term cure for some patients. SIRTeX Medical Limited has developed three separate cancer

  11. Ultraviolet radiation therapy and UVR dose models

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, David Robert, E-mail: davidrobert.grimes@oncology.ox.ac.uk [School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland and Cancer Research UK/MRC Oxford Institute for Radiation Oncology, Gray Laboratory, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ (United Kingdom)

    2015-01-15

    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.

  12. Diagnostic imaging and radiation therapy equipment

    International Nuclear Information System (INIS)

    This is the third edition of CSA Standard C22.2 No. 114 (now CAN/CSA-C22.2 No. 114), which is one of a series of standards issued by the Canadian Standards Association under Part II of the Canadian Electrical Code. This edition marks an important shift towards harmonization of Canadian requirements with those of the European community and the United States. Also important to this edition is the expansion of its scope to include the complete range of diagnostic imaging and radiation therapy equipment, rather than solely radiation-emitting equipment. In so doing, equipment previously addressed by CSA Standard C22.2 No. 125, Electromedical Equipment, specifically lasers for medical applications and diagnostic ultrasound units, is now dealt with in the new edition. By virtue of this expanded scope, many of the technical requirements in the electromedical equipment standard have been introduced to the new edition, thereby bringing CSA Standard C22.2 No. 114 up to date. 14 tabs., 16 figs

  13. Severe prostatic calcification after radiation therapy for cancer.

    Science.gov (United States)

    Jones, W A; Miller, E V; Sullivan, L D; Chapman, W H

    1979-06-01

    Severe symptomatic prostatic calcification was seen in 3 patients who had carcinoma of the prostate treated initially with transurethral resection, followed in 2 to 4 weeks by definitive radiation therapy. This complication is probably preventable if an interval of 6 weeks is allowed between transurethral resection of the prostate and radiation therapy.

  14. [Importance of sonotomography in radiation therapy (author's transl)].

    Science.gov (United States)

    Heckemann, R; Quast, U; Glaeser, L; Schmitt, G

    1976-08-01

    Ultrasound tomography provides true scale representation of body contours and organ structures. The image supplies substantial, individual geometrical data, essential for computerized radiation treatment planning. The mehtod is described. Typical planning examples for therapy are demonstrated. The value of follow up sonograms for radiation therapy is described. The limitations of the method are pointed out.

  15. 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 Section 892.5840 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5840 Radiation therapy...

  16. Neoadjuvant chemotherapy and radiation therapy compared with radiation therapy alone in advanced nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Purpose: To analyze the impact of neoadjuvant chemotherapy on the treatment of locoregionally advanced nasopharyngeal carcinoma and to assess the outcomes of patients receiving such treatment. Methods and Materials: We analyzed 137 previously untreated and histologically confirmed advanced stage nasopharyngeal carcinoma patients treated with either radiation therapy only or combined radiation therapy and chemotherapy at the Seoul National University Hospital between 1984 and 1996. The stage distribution was as follows: AJCC Stage III-21, Stage IV-61 in the radiation therapy group (RT group); AJCC Stage III-1, Stage IV-54 in neoadjuvant chemotherapy and radiation therapy group (CT/RT group). The median follow-up for surviving patients was 48 months. Results: The 5-year overall survival (OS) rates were 71% for the CT/RT group and 59% for the RT group (p = 0.04). The 5-year actuarial disease-free survival (DFS) rates were 63% for the CT/RT group and 52% for the RT group (p = 0.04). Distant metastasis (DM) incidence was significantly lower in the CT/RT group. The 5-year freedom from distant metastasis rates were 84% for the CT/RT group and 66% for the RT group (p 0.01). The incidence of locoregional failures was also lower in the CT/RT group, although this difference did not reach statistical significance (69% vs. 56%, p = 0.09) Conclusion: While not providing conclusive evidence, historical evidence from this institution suggests that neoadjuvant chemotherapy significantly improves both overall and the disease-free survival of patients with advanced stage nasopharyngeal carcinoma

  17. Application of Adaptive Counseling and Therapy to Career Counseling.

    Science.gov (United States)

    Anderson, Mary Z.; Tracey, Terence J.

    1995-01-01

    Adaptive Counseling and Therapy theory predicts that counseling efficacy depends on a match between counselor style and client readiness. Data from 137 females and 54 males showed a negative relationship between client readiness and preference for directive counseling and a curvilinear (inverted U) relationship between readiness and preference for…

  18. Radiation therapy among atomic bomb survivors, Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    In the continuing evaluations of atomic bomb survivors for late radiation effects, not only doses from the A-bombs but those from other radiation sources must be considered, for the latter may be concomitantly acting factors causing bias among these investigations. In the present study, among 73 Hiroshima and 22 Nagasaki Adult Health Study (AHS) subjects who reported receiving radiation therapy, from 1970 through 1979, the medical records of 72 and 20, respectively, were reviewed, and 41 Hiroshima and 14 Nagasaki subjects were confirmed to have received radiation therapy. The data obtained in the present study were pooled with those of the previous investigation on radiation therapy exposures of AHS subjects prior to 1970. A total of 190 subjects have been documented as receiving radiation therapy and their doses were estimated. Energies used in treatments and diseases treated are discussed. Malignancies developed subsequent to radiation therapy in seven cases; five after treatment for malignancies and two after treatment for benign diseases. Neoplasms of 12 AHS subjects may have been induced by earlier radiation therapy; 5 in the earlier study and 7 in the present one. These investigations underscore the need for continued documentation of exposures to ionizing radiation for medical reasons, especially from sources incurring relatively high doses. Bias in assessments of late radiation effects among A-bomb survivors can thus be avoided. (author)

  19. Fecundity increase supports adaptive radiation hypothesis in spider web evolution

    OpenAIRE

    Todd A. Blackledge; Coddington, Jonathan A.; Agnarsson, Ingi

    2009-01-01

    Identifying the mechanisms driving adaptive radiations is key to explaining the diversity of life. The extreme reliance of spiders upon silk for survival provides an exceptional system in which to link patterns of diversification to adaptive changes in silk use. Most of the world’s 41,000 species of spiders belong to two apical lineages of spiders that exhibit quite different silk ecologies, distinct from their ancestors. Orb spiders spin highly stereotyped webs that are suspended in air and ...

  20. Genotypic sex determination enabled adaptive radiations of extinct marine reptiles.

    Science.gov (United States)

    Organ, Chris L; Janes, Daniel E; Meade, Andrew; Pagel, Mark

    2009-09-17

    Adaptive radiations often follow the evolution of key traits, such as the origin of the amniotic egg and the subsequent radiation of terrestrial vertebrates. The mechanism by which a species determines the sex of its offspring has been linked to critical ecological and life-history traits but not to major adaptive radiations, in part because sex-determining mechanisms do not fossilize. Here we establish a previously unknown coevolutionary relationship in 94 amniote species between sex-determining mechanism and whether a species bears live young or lays eggs. We use that relationship to predict the sex-determining mechanism in three independent lineages of extinct Mesozoic marine reptiles (mosasaurs, sauropterygians and ichthyosaurs), each of which is known from fossils to have evolved live birth. Our results indicate that each lineage evolved genotypic sex determination before acquiring live birth. This enabled their pelagic radiations, where the relatively stable temperatures of the open ocean constrain temperature-dependent sex determination in amniote species. Freed from the need to move and nest on land, extreme physical adaptations to a pelagic lifestyle evolved in each group, such as the fluked tails, dorsal fins and wing-shaped limbs of ichthyosaurs. With the inclusion of ichthyosaurs, mosasaurs and sauropterygians, genotypic sex determination is present in all known fully pelagic amniote groups (sea snakes, sirenians and cetaceans), suggesting that this mode of sex determination and the subsequent evolution of live birth are key traits required for marine adaptive radiations in amniote lineages. PMID:19759619

  1. Modern role and issues of radiation therapy for benign diseases

    Energy Technology Data Exchange (ETDEWEB)

    Miyashita, Tsuguhiro; Tateno, Atsushi; Kumazaki, Tatsuo [Nippon Medical School, Tokyo (Japan)

    1999-09-01

    Cases of radiation therapy for benign diseases have diminished in number because of recent alternative methods and knowledge about radiation carcinogenesis. In contrast to this tendency, our cases of benign diseases have recently increased. The facts made us reconsider today's radiation therapy of benign diseases. We reviewed 349 patients who were diagnosed as having benign tumors or non-neoplastic conditions and treated by radiation therapy in the past sixteen years. Analyzed items were the annual transition of treatment number, sorts of diseases, patients' age and sex, and the goal of therapy. Of all radiation therapy patients, benign diseases account for 9.26%. The annual percentages were 0.5%, 6.0%, 11.2% and 13.7% at intervals of five years since 1982. The majority was 246 post-operative irradiation for keloids (71%) and 41 pituitary adenomas (12%). Compared with malignant tumors, benign disease patients were statistically younger and female-dominant. Applications of radiation therapy in keloids and pituitary adenomas had definite goals, but were unclear in other rare diseases. Benign diseases should be treated by radiation therapy as the second or third option, provided the patients have serious symptoms and their diseases do not respond to other modalities. It seems to be widely accepted that favorite cases such as keloids and pituitary adenomas are treated by radiation therapy. But, optimal radiation therapies for other rare benign diseases have not been established. Therefore, the building of databases on radiation therapy on benign diseases should be pursued. Since benign disease patients were young and female-dominant and had many remaining years, their carcinogenicity potential should be considered. (author)

  2. The genomic substrate for adaptive radiation in African cichlid fish

    OpenAIRE

    Brawand, David; Russell, Pamela

    2014-01-01

    Cichlid fishes are famous for large, diverse and replicated adaptive radiations in the Great Lakes of East Africa. To understand the molecular mechanisms underlying cichlid phenotypic diversity, we sequenced the genomes and transcriptomes of five lineages of African cichlids: the Nile tilapia (Oreochromis niloticus), an ancestral lineage with low diversity; and four members of the East African lineage: Neolamprologus brichardi/pulcher (older radiation, Lake Tanganyika), Metriaclima zebra (rec...

  3. Intensity-modulated radiation therapy: emerging cancer treatment technology

    OpenAIRE

    T.S. Hong; Ritter, M. A.; Tomé, W. A.; Harari, P.M.

    2005-01-01

    The use of intensity-modulated radiation therapy (IMRT) is rapidly advancing in the field of radiation oncology. Intensity-modulated radiation therapy allows for improved dose conformality, thereby affording the potential to decrease the spectrum of normal tissue toxicities associated with IMRT. Preliminary results with IMRT are quite promising; however, the clinical data is relatively immature and overall patient numbers remain small. High-quality IMRT requires intensive physics support and ...

  4. Optimal approach in early breast cancer: Radiation therapy

    OpenAIRE

    Poortmans, Philip

    2013-01-01

    Radiation therapy significantly reduces by at least 70% the relative risk of local and regional recurrences for breast cancer after surgery. A positive influence on overall survival has been clearly demonstrated, especially for patients with a high absolute risk for locoregional recurrences. However, this is partially counterbalanced by late toxicity (dependent upon the radiation dose) especially to cardiac structures. Apart from this toxicity, a clear influence of radiation-therapy-related f...

  5. ENZO+MORAY: radiation hydrodynamics adaptive mesh refinement simulations with adaptive ray tracing

    Science.gov (United States)

    Wise, John H.; Abel, Tom

    2011-07-01

    We describe a photon-conserving radiative transfer algorithm, using a spatially-adaptive ray-tracing scheme, and its parallel implementation into the adaptive mesh refinement cosmological hydrodynamics code ENZO. By coupling the solver with the energy equation and non-equilibrium chemistry network, our radiation hydrodynamics framework can be utilized to study a broad range of astrophysical problems, such as stellar and black hole feedback. Inaccuracies can arise from large time-steps and poor sampling; therefore, we devised an adaptive time-stepping scheme and a fast approximation of the optically-thin radiation field with multiple sources. We test the method with several radiative transfer and radiation hydrodynamics tests that are given in Iliev et al. We further test our method with more dynamical situations, for example, the propagation of an ionization front through a Rayleigh-Taylor instability, time-varying luminosities and collimated radiation. The test suite also includes an expanding H II region in a magnetized medium, utilizing the newly implemented magnetohydrodynamics module in ENZO. This method linearly scales with the number of point sources and number of grid cells. Our implementation is scalable to 512 processors on distributed memory machines and can include the radiation pressure and secondary ionizations from X-ray radiation. It is included in the newest public release of ENZO.

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

    Directory of Open Access Journals (Sweden)

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

    2012-01-01

    Full Text Available 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.

  7. Polymer gel dosimetry system for radiation therapy

    International Nuclear Information System (INIS)

    Purpose/Objective: Recently developed treatment modalities such as stereotactic and conformal radiation therapy produce complex dose distributions which are difficult or impractical to measure with conventional dosimetry instrumentation. Three-dimensional treatment planning systems which purport to calculate these complex dose distributions should be compared to experimental results before being routinely applied to clinical problems. There is a need for a new class of tissue-equivalent dosimeters capable of providing accurate, high resolution, time-integrated and three dimensional dose distributions. The recently developed BANG polymer gel dosimetry system (MGS Research, Inc., Guilford, CT) is ideally suited for the task described above. Physico-chemical principles of the polymer gel dosimetry are presented, together with examples of its application to radiation therapy. Data analysis and display program, written for Macintosh computer, is demonstrated. Materials and Methods: Radiation-induced polymerization of acrylic monomers, which are dispersed in tissue-equivalent gelatin, has been shown to be dependent on the dose, but independent of the dose rate or photon energy. Therefore, the spatial distribution of polymer in the gel is precisely representative of the dose distribution. As the polymeric microparticles reduce the water proton NMR relaxation times in the gel, the dose distribution can be measured with high resolution and accuracy using magnetic resonance imaging. Also, as these microparticles cannot diffuse through the gelatin matrix, their distribution is permanent. An improved formulation of the BANG dosimeter consists of 3% w/v acrylic acid, 3% N,N'-methylene-bis-acrylamide, 1% sodium hydroxide, 5% gelatin, and 88% water. MR images are transferred via a local network to a Macintosh computer, and R2 maps constructed on the basis of multiple TE images, using a non-linear least squares fit based on the Levenberg-Marquardt algorithm. A dose-to-R2

  8. Recurrent spontaneous pneumothorax after radiation therapy to the thorax

    Energy Technology Data Exchange (ETDEWEB)

    Twiford, T.W. Jr.; Zornoza, J.; Libshitz, H.I.

    1978-03-01

    Two patients who received radiation therapy to the thorax and who developed recurrent spontaneous pneumothoraces are presented. Patients with recurrent pneumothoraces secondary to radiation have not been described previously. Pleural changes secondary to radiation may contribute significantly to the complicated clinical course of these patients.

  9. Localized fibrous mesothelioma of pleura following external ionizing radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Bilbey, J.H.; Mueller, N.L.M.; Miller, R.R.; Nelems, B.

    1988-12-01

    Carcinogenesis is a well-known complication of radiation exposure. Ionizing radiation also leads to an increased incidence of benign tumors. A 36-year-old woman had a localized fibrous mesothelioma of the pleura and an ipsilateral breast carcinoma 23 years after receiving external radiation therapy for treatment of a chest wall keloid.

  10. 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.

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

    Science.gov (United States)

    Dehlaghi, Vahab; Taghipour, Mostafa; Haghparast, Abbas; Roshani, Gholam Hossein; Rezaei, Abbas; Shayesteh, Sajjad Pashootan; Adineh-Vand, Ayoub; Karimi, Gholam Reza

    2015-01-01

    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/D0), 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. PMID:25498836

  12. Intraoperative radiation therapy for malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Noboru; Yamada, Hiromu; Andoh, Takashi; Takada, Mitsuaki; Hirata, Toshifumi; Funakoshi, Takashi; Doi, Hidetaka; Yanagawa, Shigeo (Gifu Univ. (Japan). Faculty of Medicine)

    1989-04-01

    Intraoperative radiation therapy (IOR) is an ideal means of exterminating residual tumor after surgical resection. In this study, the clinical results of IOR using a Scanditronix Microtron MM-22 were evaluated in 14 patients with malignant glioma, five of whom had recurrent tumors. Between July, 1985 and October, 1986, 11 patients with glioblastoma multiforme (GB) were irradiated 18 times (mean, 1.6 times/case), and three with astrocytoma (Kernohan grade III) underwent IOR once each. The target-absorbed dose at 1 to 2 cm deeper than the tumor resection surface was 15 to 50 Gy. During irradiation, a cotton bolus was placed in the dead space after over 91% of the tumor had been resected. As a rule, external irradiation therapy was also given postoperatively at a dose of 30 to 52 Gy. One patient died of pneumonia and disseminated intravascular coagulation syndrome 1 month postoperatively. The 1- and 2-year survival rates of the ramaining 13 patients were 84.6% and 61.5%, respectively; among the 10 with GB, they were 80% and 50%. Generally, the smaller the tumor size, the better the results. There were no adverse effects, despite the dose 15 to 50 Gy applied temporally to the tumor bed. IOR was especially effective against small, localized tumors, but was not always beneficial in cases of large tumors, particularly those with a contralateral focus. The improved survival rate in this series demonstrates that IOR is significantly effective in the 'induction of remission' following surgical excision of malignant gliomas. (author).

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

    Science.gov (United States)

    Lee, Katrina; Lenards, Nishele; Holson, Janice

    2016-01-01

    The hippocampus is responsible for memory and cognitive function. An ongoing phase II clinical trial suggests that sparing dose to the hippocampus during whole-brain radiation therapy can help preserve a patient׳s neurocognitive function. Progressive research and advancements in treatment techniques have made treatment planning more sophisticated but beneficial for patients undergoing treatment. The aim of this study is to evaluate and compare hippocampal sparing whole-brain (HS-WB) radiation therapy treatment planning techniques using volume-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT). We randomly selected 3 patients to compare different treatment techniques that could be used for reducing dose to the hippocampal region. We created 2 treatment plans, a VMAT and an IMRT, from each patient׳s data set and planned on the Eclipse 11.0 treatment planning system (TPS). A total of 6 plans (3 IMRT and 3 VMAT) were created and evaluated for this case study. The physician contoured the hippocampus as per the Radiation Therapy Oncology Group (RTOG) 0933 protocol atlas. The organs at risk (OR) were contoured and evaluated for the plan comparison, which included the spinal cord, optic chiasm, the right and left eyes, lenses, and optic nerves. Both treatment plans produced adequate coverage on the planning target volume (PTV) while significantly reducing dose to the hippocampal region. The VMAT treatment plans produced a more homogenous dose distribution throughout the PTV while decreasing the maximum point dose to the target. However, both treatment techniques demonstrated hippocampal sparing when irradiating the whole brain. PMID:26235550

  14. Radiation Therapy for Chloroma (Granulocytic Sarcoma)

    Energy Technology Data Exchange (ETDEWEB)

    Bakst, Richard; Wolden, Suzanne [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Yahalom, Joachim, E-mail: yahalomj@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    2012-04-01

    Objectives: Chloroma (granulocytic sarcoma) is a rare, extramedullary tumor of immature myeloid cells related to acute nonlymphocytic leukemia or myelodysplastic syndrome. Radiation therapy (RT) is often used in the treatment of chloromas; however, modern studies of RT are lacking. We reviewed our experience to analyze treatment response, disease control, and toxicity associated with RT to develop treatment algorithm recommendations for patients with chloroma. Patients and Methods: Thirty-eight patients who underwent treatment for chloromas at our institution between February 1990 and June 2010 were identified and their medical records were reviewed and analyzed. Results: The majority of patients that presented with chloroma at the time of initial leukemia diagnosis (78%) have not received RT because it regressed after initial chemotherapy. Yet most patients that relapsed or remained with chloroma after chemotherapy are in the RT cohort (90%). Thirty-three courses of RT were administered to 22 patients. Radiation subsite breakdown was: 39% head and neck, 24% extremity, 9% spine, 9% brain, 6% genitourinary, 6% breast, 3% pelvis, and 3% genitourinary. Median dose was 20 (6-36) Gy. Kaplan-Meier estimates of progression-free survival and overall survival in the RT cohort were 39% and 43%, respectively, at 5 years. At a median follow-up of 11 months since RT, only 1 patient developed progressive disease at the irradiated site and 4 patients developed chloromas at other sites. RT was well tolerated without significant acute or late effects and provided symptom relief in 95% of cases. Conclusions: The majority of patients with chloromas were referred for RT when there was extramedullary progression, marrow relapse, or rapid symptom relief required. RT resulted in excellent local disease control and palliation of symptoms without significant toxicity. We recommend irradiating chloromas to at least 20 Gy, and propose 24 Gy in 12 fractions as an appropriate regimen.

  15. Predicting Radiation Pneumonitis After Stereotactic Ablative Radiation Therapy in Patients Previously Treated With Conventional Thoracic Radiation Therapy

    International Nuclear Information System (INIS)

    Purpose: To determine the incidence of and risk factors for radiation pneumonitis (RP) after stereotactic ablative radiation therapy (SABR) to the lung in patients who had previously undergone conventional thoracic radiation therapy. Methods and Materials: Seventy-two patients who had previously received conventionally fractionated radiation therapy to the thorax were treated with SABR (50 Gy in 4 fractions) for recurrent disease or secondary parenchymal lung cancer (T 10 and mean lung dose (MLD) of the previous plan and the V10-V40 and MLD of the composite plan were also related to RP. Multivariate analysis revealed that ECOG PS scores of 2-3 before SABR (P=.009), FEV1 ≤65% before SABR (P=.012), V20 ≥30% of the composite plan (P=.021), and an initial PTV in the bilateral mediastinum (P=.025) were all associated with RP. Conclusions: We found that severe RP was relatively common, occurring in 20.8% of patients, and could be predicted by an ECOG PS score of 2-3, an FEV1 ≤65%, a previous PTV spanning the bilateral mediastinum, and V20 ≥30% on composite (previous RT+SABR) plans. Prospective studies are needed to validate these predictors and the scoring system on which they are based.

  16. 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)

  17. Are Organisms Adapting to Ionizing Radiation at Chernobyl?

    Science.gov (United States)

    Møller, Anders Pape; Mousseau, Timothy Alexander

    2016-04-01

    Numerous organisms have shown an ability to survive and reproduce under low-dose ionizing radiation arising from natural background radiation or from nuclear accidents. In a literature review, we found a total of 17 supposed cases of adaptation, mostly based on common garden experiments with organisms only deriving from typically two or three sampling locations. We only found one experimental study showing evidence of improved resistance to radiation. Finally, we examined studies for the presence of hormesis (i.e., superior fitness at low levels of radiation compared with controls and high levels of radiation), but found no evidence to support its existence. We conclude that rigorous experiments based on extensive sampling from multiple sites are required. PMID:26868287

  18. Radiation therapy for long-bone metastases

    Energy Technology Data Exchange (ETDEWEB)

    Wadasaki, Kouichi; Tomiyoshi, Hideki; Ooshima, Yoshie; Urashima, Masaki; Mori, Masaki (Hiroshima Red Cross Hospital and Atomic-Bomb Survivors Hospital (Japan))

    1992-09-01

    Efficacy of palliative and prophylactic radiotherapies for metastatic bone pain and pathological fracture was investigated in 14 patients with long bone metastases. Irradiation sites were the femur in 10 patients, the humerus in 2, the radius in one, and the tibia in one. Radiographs showed osteolytic lesion in 13 patients and osteoblastic lesion in one. A total dose of 48.6 Gy to 87.3 Gy was delivered in daily fractional doses of 2 Gy (one patient), 2.5 Gy (3), 3 Gy (6), 4 Gy (2) and 5 Gy (2), 5 days a week. For 13 patients, except for one death within one month after the completion of irradiation, pain relief was attained. Of these patients, 7 (54%) had complete pain relief. In one patient, pathological fracture occurred as early as 10 days after the beginning of irradiation when irradiation efficacy was not attained. In none of the 13 others, was pathological fracture encountered. No side effects were seen at all during or after irradiation. Radiation therapy was an extremely effective means for managing patients with long bone metastases in terms of its palliative and prophylactic role. (N.K.).

  19. 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.

  20. Frequency adaptation for enhanced radiation force amplitude in dynamic elastography.

    Science.gov (United States)

    Ouared, Abderrahmane; Montagnon, Emmanuel; Kazemirad, Siavash; Gaboury, Louis; Robidoux, André; Cloutier, Guy

    2015-08-01

    In remote dynamic elastography, the amplitude of the generated displacement field is directly related to the amplitude of the radiation force. Therefore, displacement improvement for better tissue characterization requires the optimization of the radiation force amplitude by increasing the push duration and/or the excitation amplitude applied on the transducer. The main problem of these approaches is that the Food and Drug Administration (FDA) thresholds for medical applications and transducer limitations may be easily exceeded. In the present study, the effect of the frequency used for the generation of the radiation force on the amplitude of the displacement field was investigated. We found that amplitudes of displacements generated by adapted radiation force sequences were greater than those generated by standard nonadapted ones (i.e., single push acoustic radiation force impulse and supersonic shear imaging). Gains in magnitude were between 20 to 158% for in vitro measurements on agar-gelatin phantoms, and 170 to 336% for ex vivo measurements on a human breast sample, depending on focus depths and attenuations of tested samples. The signal-to-noise ratio was also improved more than 4-fold with adapted sequences. We conclude that frequency adaptation is a complementary technique that is efficient for the optimization of displacement amplitudes. This technique can be used safely to optimize the deposited local acoustic energy without increasing the risk of damaging tissues and transducer elements.

  1. Radiation therapy and host immunity in malignant tumors

    International Nuclear Information System (INIS)

    Host resistance to the growth of neoplastic cells has been a subject of intense interest for many years. The recent demonstration that many tumors in man have tumor-associated antigens has provided a firm basis for experimental investigations of this resistance. Thus, it is important to determine whether radiation therapy for malignant tumors incurs detrimental effects on the host resistance. This article reviews the information on the relationship of radiation therapy to patient's immune status, and discusses the concept that in radiation therapy for cancer, the patient's immunological responses to the malignat tumor must be considered. (auth.)

  2. Natural health products and cancer chemotherapy and radiation therapy

    Directory of Open Access Journals (Sweden)

    Doreen Oneschuk

    2011-12-01

    Full Text Available Complementary therapies, notably natural health products such as herbs and vitamins, are frequently used by cancer patients receiving chemotherapy and radiation therapy. There is much controversy as to whether these natural health products should be taken during conventional cancer treatments. Supporters of this practice cite beneficial effects of the antioxidant properties, while opponents are concerned about the potential for natural health product-chemotherapy/radiation related negative interactions. This involves understanding the role and effect on metabolizing enzymes. This review will highlight the present evidence for both the beneficial and negative consequences of the use of natural health products during chemotherapy and radiation therapy.

  3. 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

  4. Particle beam radiation therapy:re-introducing the future

    Institute of Scientific and Technical Information of China (English)

    Omar Abdel-Rahman

    2014-01-01

    Particle radiation therapy is an exciting area of radiotherapy basic and clinical researches. The majority of particle radiotherapy work is being done with proton beams having essential y the same radiobiologic properties as conventional photon/electron radiation but al owing a much more precise control of the radiation dose distribution. However, other charged particles are also playing an increasing role, like neutrons. In this review article we wil summarize the data related to basic and clinical experiences related to particle beam radiation therapy.

  5. Mesenchymal stem cell therapy for acute radiation syndrome.

    Science.gov (United States)

    Fukumoto, Risaku

    2016-01-01

    Acute radiation syndrome affects military personnel and civilians following the uncontrolled dispersal of radiation, such as that caused by detonation of nuclear devices and inappropriate medical treatments. Therefore, there is a growing need for medical interventions that facilitate the improved recovery of victims and patients. One promising approach may be cell therapy, which, when appropriately implemented, may facilitate recovery from whole body injuries. This editorial highlights the current knowledge regarding the use of mesenchymal stem cells for the treatment of acute radiation syndrome, the benefits and limitations of which are under investigation. Establishing successful therapies for acute radiation syndrome may require using such a therapeutic approach in addition to conventional approaches. PMID:27182446

  6. Proton minibeam radiation therapy: Experimental dosimetry evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Peucelle, C.; Martínez-Rovira, I.; Prezado, Y., E-mail: prezado@imnc.in2p3.fr [IMNC-UMR 8165, CNRS, Paris 7 and Paris 11 Universities, 15 rue Georges Clemenceau, Orsay Cedex 91406 (France); Nauraye, C.; Patriarca, A.; Hierso, E.; Fournier-Bidoz, N. [Institut Curie - Centre de Protonthérapie d’Orsay, Campus Universitaire, Bât. 101, Orsay 91898 (France)

    2015-12-15

    Purpose: Proton minibeam radiation therapy (pMBRT) is a new radiotherapy (RT) approach that allies the inherent physical advantages of protons with the normal tissue preservation observed when irradiated with submillimetric spatially fractionated beams. This dosimetry work aims at demonstrating the feasibility of the technical implementation of pMBRT. This has been performed at the Institut Curie - Proton Therapy Center in Orsay. Methods: Proton minibeams (400 and 700 μm-width) were generated by means of a brass multislit collimator. Center-to-center distances between consecutive beams of 3200 and 3500 μm, respectively, were employed. The (passive scattered) beam energy was 100 MeV corresponding to a range of 7.7 cm water equivalent. Absolute dosimetry was performed with a thimble ionization chamber (IBA CC13) in a water tank. Relative dosimetry was carried out irradiating radiochromic films interspersed in a IBA RW3 slab phantom. Depth dose curves and lateral profiles at different depths were evaluated. Peak-to-valley dose ratios (PVDR), beam widths, and output factors were also assessed as a function of depth. Results: A pattern of peaks and valleys was maintained in the transverse direction with PVDR values decreasing as a function of depth until 6.7 cm. From that depth, the transverse dose profiles became homogeneous due to multiple Coulomb scattering. Peak-to-valley dose ratio values extended from 8.2 ± 0.5 at the phantom surface to 1.08 ± 0.06 at the Bragg peak. This was the first time that dosimetry in such small proton field sizes was performed. Despite the challenge, a complete set of dosimetric data needed to guide the first biological experiments was achieved. Conclusions: pMBRT is a novel strategy in order to reduce the side effects of RT. This works provides the experimental proof of concept of this new RT method: clinical proton beams might allow depositing a (high) uniform dose in a brain tumor located in the center of the brain (7.5 cm depth

  7. Results of radiation therapy for medulloblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Shibamoto, Yuta; Abe, Mitsuyuki; Tsutsui, Kazushige; Ono, Koji (Kyoto Univ. (Japan). Faculty of Medicine); Takahashi, Masaji

    1989-12-01

    Results of radiation therapy for cerebellar medulloblastoma at Kyoto University Hospital were reviewed. Between 1962 and 1988, 30 patients with histologically-proven medulloblastoma completed radiotherapy. Before 1971, the treatment volume was either the posterior fossa only or posterior fossa plus spinal axis, but after 1972, it was extended to include the entire neuraxis. The mean dose was 48 Gy to the posterior fossa, 36 Gy to the whole brain, and 25 Gy to the spinal axis. The 5-year survival rate and 5-year relapse-free survival rate estimated by the Kaplan-Meier's method were 36% and 37%, respectively, for total cases, but were as high as 79% and 80%, respectively, for the recent 10 patients. This improvement in the treatment results appeared to be due to extensive tumor resection and improved radiotherapy technique, and not to the use of chemotherapy. The prognosis was significantly better in patients treated with craniospinal irradiation than in those otherwise treated. There was a trend towards better survival in patients who received 50 Gy or more to the posterior fossa or 24 Gy or more to the spinal axis, compared to the patients who received lower doses to each site. No significant morbidity of radiotherapy was seen. Four of the six surviving patients who were treated below age 12 have a mental retardation and/or a short stature, but one patient treated at age 5 has a normal growth and a good intelligence. From these analysis, it is recommended to irradiate craniospinal axis and posterior fossa up to 25{approx}35 Gy and 50{approx}55 Gy, respectively. (author).

  8. Radiation Therapy Result of Polymorphic Reticulosis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eun Ji; Kim, Gwi Eon; Park, Young Nyun [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1993-06-15

    During the period from January, 1975, to June, 1989, one hundred patients with histopathologically proven polymorphic reticulosis in the upper respiratory tract were treated with radiation therapy and the analysis of treatment results was undertaken. One hundred patients (69 males, 31 females) with a mean age of 46 years (range 12-79 years) were presented. Nasal cavity was the most frequent site of involvement(56%), and 44 cases had multifocal sites of involvement. The incidence of cervical lymph node metastasis at initial diagnosis was 24%. Staging was determined by Ann-Arbor classification, retrospectively. The number of patients of stage IE, IIE, IIIE and IVE were 35, 60, 1, and 4, respectively. The overall 5 year actuarial survival rates were 38.4%. The difference in 5 year survival rates between patients with stage IE and IIE, with solitary and multiple, with CR and PR after irradiation were significant statistically. For the analysis of failure patterns, failure sites include the following: local failure alone(30/55=54.6%), systemic failure alone(9/55=16.4%), both local and systemic failure(16/55=29.0%). Retrograde slide review was available in 29 cases of PMR with respect to histopathologic bases, and immunohistochemical studies were performed using MTI and DACO-UCHL-1 as T-cell markers, MB2 as a B-cell marker and alpha-1-antichymotrypsin as a histiocytic markers. All that 29 cases showed characteristic histologic features similar to those of peripheral T-cell lymphoma and showed positive reactio to the T-cell marker. These findings suggest strongly that quite a significant portion of PMR may be in fact T-cell lymphoma.

  9. Radiation protection concepts review with an adapted quiz commercial game

    International Nuclear Information System (INIS)

    Before a new employee starts working at EMBRARAD under a large irradiation operator supervision, he has to attend the first radiation protection training. After that all radiation protection subjects are revised every six months. In that half-yearly training the employees are chosen randomly to explain radiation protection subjects to other participants under an instructor supervision. After some years attending the same training, employees do not have motivation to participate in this kind of periodic event due to the same issues covered. Therefore something should be made to revival their interest and motivation to take part in this periodic training. The way chose was adapted a commercial game to revised radiation protection subjects and included it in the periodic training. The game was well accepted by the employees, it caused a competition among them because everybody wanted to win the game and consequently stimulated them to study. (author)

  10. Radiation dermatitis following electron beam therapy

    International Nuclear Information System (INIS)

    Ten patients, who had been treated for mycosis fungoides with electron beam radiation ten or more years previously, were examined for signs of radiation dermatitis. Although most patients had had acute radiation dermatitis, only a few manifested signs of mild chronic changes after having received between 1,000 and 2,800 rads

  11. Radiation dermatitis following electron beam therapy

    Energy Technology Data Exchange (ETDEWEB)

    Price, N.M.

    1978-01-01

    Ten patients, who had been treated for mycosis fungoides with electron beam radiation ten or more years previously, were examined for signs of radiation dermatitis. Although most patients had had acute radiation dermatitis, only a few manifested signs of mild chronic changes after having received between 1,000 and 2,800 rads.

  12. Pneumothorax following thoracic radiation therapy for Hodgkin's disease

    International Nuclear Information System (INIS)

    Radiation therapy alone to the nodal drainage sites above the diaphragm, namely a ''mantle'' field, is often standard treatment for early stage Hodgkin's disease and may be used in combination with chemotherapy in more advanced disease. Localised pneumonitis and fibrosis are recognised treatment related sequelae; however, other pulmonary complications, including pneumothorax, have been described. Two cases of spontaneous pneumothorax following mantle radiation therapy are presented. (author)

  13. Natural health products and cancer chemotherapy and radiation therapy

    OpenAIRE

    Doreen Oneschuk; Jawaid Younus

    2011-01-01

    Complementary therapies, notably natural health products such as herbs and vitamins, are frequently used by cancer patients receiving chemotherapy and radiation therapy. There is much controversy as to whether these natural health products should be taken during conventional cancer treatments. Supporters of this practice cite beneficial effects of the antioxidant properties, while opponents are concerned about the potential for natural health product-chemotherapy/radiation related negative in...

  14. Superficial Radiation Therapy for the Treatment of Nonmelanoma Skin Cancers.

    Science.gov (United States)

    McGregor, Sean; Minni, John; Herold, David

    2015-12-01

    Superficial radiation therapy has become more widely available to dermatologists. With the advent of more portable machines, it has become more convenient for dermatology practices to employ in an office-based setting. The goal of this paper is to provide a deeper insight into the role of superficial radiation therapy in dermatology practice and to review the current literature surrounding its use in the treatment of both basal and squamous cell carcinomas.

  15. Clinical Oral Examinations: Assessment of Competency in Radiation Therapy

    OpenAIRE

    Leech, Michelle; POOLE, CLAIRE; CRAIG, AGNELLA; COFFEY, MARY ANNE; NI CHUINNEAGAIN, SIOBHAN

    2009-01-01

    Matching assessment strategies to learning outcomes in radiation therapy education is of the utmost importance. Assessing clinical competence requires that `competence? be clearly defined prior to the start of any clinical programme. In this article, we report on our experience in using clinical oral examinations in assessing competence in second year undergraduate radiation therapy students. The shortcomings of clinical oral examinations such as `leaking? of the agenda are addressed and more...

  16. Factors influencing radiation therapy student clinical placement satisfaction

    OpenAIRE

    Bridge, Pete; Carmichael, Mary-Ann

    2014-01-01

    Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clini...

  17. Thyroid neoplasia following radiation therapy for Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    The question of thyroid neoplasia following high-dose radiation treatment to the neck and mediastinum for malignant neoplasms such as Hodgkin's lymphoma in children and young adults has been raised recently. Five patients, 19 to 39 years old, were operated on for thyroid neoplasms that developed following cervical and mediastinal radiation therapy for Hodgkin's lymphoma. Three patients had papillary carcinomas and two had follicular adenomas. The latency period between radiation exposure and the diagnosis of thyroid neoplasm ranged from eight to 16 years. This limited series provided strong support for the recommendation that children and young adults who are to receive high-dose radiation therapy to the head, neck, and mediastinum should receive suppressive doses of thyroxine prior to radiation therapy in order to suppress thyrotropin (thyroid-stimulating hormone) and then be maintained on a regimen of suppression permanently

  18. 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.

  19. 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.

  20. 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.

  1. Adaptation of radiation shielding code to space environment

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, Koichi; Hara, Akihisa (Hazama Corp., Tokyo (Japan))

    1992-12-01

    Recently, the trend to the development of space has heightened. To the development of space, many problems are related, and as one of them, there is the protection from cosmic ray. The cosmic ray is the radiation having ultrahigh energy, and there was not the radiation shielding design code that copes with cosmic ray so far. Therefore, the high energy radiation shielding design code for accelerators was improved so as to cope with the peculiarity that cosmic ray possesses. Moreover, the calculation of the radiation dose equivalent rate in the moon base to which the countermeasures against cosmic ray were taken was simulated by using the improved code. As the important countermeasures for the safety protection from radiation, the covering with regolith is carried out, and the effect of regolith was confirmed by using the improved code. Galactic cosmic ray, solar flare particles, radiation belt, the adaptation of the radiation shielding code HERMES to space environment, the improvement of the three-dimensional hadron cascade code HETCKFA-2 and the electromagnetic cascade code EGS 4-KFA, and the cosmic ray simulation are reported. (K.I.).

  2. Spontaneous pneumothorax after upper mantle radiation therapy for Hodgkin disease

    International Nuclear Information System (INIS)

    Between 1967 and 1981, 158 of 256 consecutive adult patients received upper mantle (UM) radiation therapy as part of initial treatment of Hodgkin disease at the Hamilton Regional Cancer Centre. Chemotherapy was also part of the initial treatment in 21 of 158 patients who received UM radiation therapy. Spontaneous pneumothorax was observed in six of 158 patients during remission after UM radiation therapy in this series. Three cases were incidental findings on follow-up radiographs, but three other patients were seen initially with symptoms of spontaneous pneumothorax. The entity occurred in three of 21 patients (14%) treated with UM radiation therapy and chemotherapy, and in three of 137 (2%) treated with UM radiation therapy (P < .05). Within the range of UM doses (3,500-4,000 cGy in 4 weeks), higher dose was not associated with higher risk of spontaneous pneumothorax. Although these cases of spontaneous pneumothorax are clustered in an age range classic for this entity, the incidence of spontaneous pneumothorax in this group of patients is higher than the anticipated lifetime incidence of 1:500 for the general population. This risk of spontaneous pneumothorax after UM radiation therapy may be even higher in patients who also receive chemotherapy

  3. An Investigation of Vascular Strategies to Augment Radiation Therapy

    Science.gov (United States)

    El Kaffas, Ahmed Nagy

    Radiation therapy is administered to more than 50% of patients diagnosed with cancer. Mechanisms of interaction between radiation and tumour cells are relatively well understood on a molecular level, but much remains uncertain regarding how radiation interacts with the tumour as a whole. Recent studies have suggested that tumour response to radiation may in fact be regulated by endothelial cell response, consequently stressing the role of tumour blood vessels in radiation treatment response. As a result, various treatment regimens have been proposed to strategically combine radiation with vascular targeting agents. A great deal of effort has been aimed towards developing efficient vascular targeting agents. Nonetheless, no optimal method has yet been devised to strategically deliver such agents. Recent evidence suggesting that these drugs may "normalize" tumour blood vessels and enhance radiosensitivity, is supporting experiments where anti-angiogenic drugs are combined with cytotoxic therapies such as radiotherapy. In contrast, ultrasound-stimulated microbubbles have recently been demonstrated to enhance radiation therapy by biophysically interacting with endothelial cells. When combined with single radiation doses, these microbubbles are believed to cause localized vascular destruction followed by tumour cell death. Finally, a new form of 'pro-angiogenics' has also been demonstrated to induce a therapeutic tumour response. The overall aim of this thesis is to study the role of tumour blood vessels in treatment responses to single-dose radiation therapy and to investigate radiation-based vascular targeting strategies. Using pharmacological and biophysical agents, blood vessels were altered to determine how they influence tumour cell death, clonogenicity, and tumour growth, and to study how these may be optimally combined with radiation. Three-dimensional high-frequency power Doppler ultrasound was used throughout these studies to investigate vascular response to

  4. 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…

  5. The Radiation Therapy Oncology in the context of oncological practice

    International Nuclear Information System (INIS)

    This work is about the radiation therapy oncology in the context of oncological practice. The radiotherapy is a speciality within medicine that involves the generation, application and dissemination of knowledge about the biology, causes, prevention and treatment of the cancer and other pathologies by ionising radiation

  6. The therapy of marrowy syndrome at radiation lesions

    International Nuclear Information System (INIS)

    In this chapter author made conclusion that cumulative data on experimental therapy of radiation affections testify to the effect that at critical radiation sickness of heavy level following hematosis oppression effective can be only that treatment regimen, which contains resources conducive to reducing processes in the marrow

  7. 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 Section 892.5750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5750 Radionuclide radiation...

  8. Adaptive radiation-induced epigenetic alterations mitigated by antioxidants

    OpenAIRE

    Bernal, Autumn J.; Dolinoy, Dana C; Huang, Dale; Skaar, David A.; Weinhouse, Caren; Jirtle, Randy L

    2013-01-01

    Humans are exposed to low-dose ionizing radiation (LDIR) from a number of environmental and medical sources. In addition to inducing genetic mutations, there is concern that LDIR may also alter the epigenome. Such heritable effects early in life can either be positively adaptive or result in the enhanced formation of diseases, including cancer, diabetes, and obesity. Herein, we show that LDIR significantly increased DNA methylation at the viable yellow agouti (Avy) locus in a sex-specific man...

  9. Once-Daily Radiation Therapy for Inflammatory Breast Cancer

    International Nuclear Information System (INIS)

    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

  10. 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

  11. Acute and Chronic Cutaneous Reactions to Ionizing Radiation Therapy

    OpenAIRE

    Bray, Fleta N.; Simmons, Brian J.; Aaron H. Wolfson; Nouri, Keyvan

    2016-01-01

    Ionizing radiation is an important treatment modality for a variety of malignant conditions. However, development of radiation-induced skin changes is a significant adverse effect of radiation therapy (RT). Cutaneous repercussions of RT vary considerably in severity, course, and prognosis. When they do occur, cutaneous changes to RT are commonly graded as acute, consequential-late, or chronic. Acute reactions can have severe sequelae that impact quality of life as well as cancer treatment. Th...

  12. [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.

  13. 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.

  14. Development of medical application methods using radiation. Radionuclide therapy

    International Nuclear Information System (INIS)

    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

  15. Focal Therapy, Differential Therapy, and Radiation Treatment for Prostate Cancer

    OpenAIRE

    Jain, Anudh K.; Ennis, Ronald D

    2012-01-01

    Focal and differential therapy represent an approach to improve the therapeutic ratio of prostate cancer treatments. This concept is a shift from treating the whole gland to intensely treating the portion of the gland that contains significant tumor. However, there are many challenges in the move towards focal approaches. Defining which patients are suitable candidates for focal therapy approaches is an area of significant controversy, and it is likely that additional data from imaging or det...

  16. 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)

  17. Radiation Therapy for Neovascular Age-related Macular Degeneration

    International Nuclear Information System (INIS)

    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

  18. Reversible brachial plexopathy following primary radiation therapy for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Salner, A.L.; Botnick, L.E.; Herzog, A.G.; Goldstein, M.A.; Harris, J.R.; Levene, M.B.; Hellman, S.

    Reversible brachial plexopathy has occurred in very low incidence in patients with breast carcinoma treated definitively with radiation therapy. Of 565 patients treated between January 1968 and December 1979 with moderate doses of supervoltage radiation therapy (average axillary dose of 5000 rad in 5 weeks), eight patients (1.4%) developed the characteristic symptoms at a median time of 4.5 months after radiation therapy. This syndrome consists of paresthesias in all patients, with weakness and pain less commonly seen. The symptom complex differs from other previously described brachial plexus syndromes, including paralytic brachial neuritis, radiation-induced injury, and carcinoma. A possible relationship to adjuvant chemotherapy exists, though the etiology is not well-understood. The cases described demonstrate temporal clustering. Resolution is always seen.

  19. NEW DEVELOPMENTS IN RADIATION THERAPY FOR HEAD AND NECK CANCER: INTENSITY MODULATED RADIATION THERAPY AND HYPOXIA TARGETING

    OpenAIRE

    Lee, Nancy Y.; Le, Quynh-Thu

    2008-01-01

    Intensity modulated radiation therapy (IMRT) has revolutionized radiation treatment for head and neck cancers (HNC). When compared to the traditional techniques, IMRT has the unique ability to minimize the dose delivered to normal tissues without compromising tumor coverage. As a result, side effects from high dose radiation have decreased and patient quality of life has improved. In addition to toxicity reduction, excellent clinical outcomes have been reported for IMRT. The first part of thi...

  20. Acid ceramidase in prostate cancer radiation therapy resistance and relapse

    Science.gov (United States)

    Cheng, Joseph C.

    Prostate tumor cell escape from ionizing radiation (IR)-induced killing can lead to disease progression and relapse. Sphingolipids such as ceramide and sphingosine 1-phosphate influence signal transduction pathways that regulate stress response in cancer cells. In particular, metabolism of apoptotic ceramide constitutes an important survival adaptation. Assessments of enzyme activity, mRNA, and protein demonstrated preferential upregulation of the ceramide deacylating enzyme acid ceramidase (AC) in irradiated cancer cells. Promoter-reporter and ChIP-qPCR assays revealed AC transcription by activator protein 1 (AP-1) is sensitive to pharmacological inhibition of de novo ceramide biosynthesis, identifying a protective feedback mechanism that mitigates the effects of IR-induced ceramide. Deregulation of c-Jun, in particular, induced marked radiosensitization in vitro and in vivo, which was rescued by ectopic AC over-expression. AC over-expression in prostate cancer clonogens surviving 80 Gray fractionated irradiation was associated with increased radioresistance and proliferation, suggesting a role in radiotherapy failure and relapse. Indeed, immunohistochemical analysis of human prostate cancer tissues revealed higher levels of AC after radiotherapy failure than therapy-naive adenocarcinoma, PIN, or benign tissues. By genetically downregulating AC with small interfering RNA (siRNA), we observed radiosensitization of cells using clonogenic and cytotoxicity assays. Finally, treatment with lysosomotropic small molecule inhibitors of AC, LCL385 or LCL521, induced prostate cancer xenograft radiosensitization and long-term suppression, suggesting AC is a tractable target for adjuvant radiotherapy.

  1. 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....

  2. 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.

  3. Alterations of nutritional status: impact of chemotherapy and radiation therapy

    International Nuclear Information System (INIS)

    The nutritional status of a cancer patient may be affected by the tumor, the chemotherapy and/or radiation therapy directed against the tumor, and by complications associated with that therapy. Chemotherpay-radiotherapy is not confined exclusively to malignant cell populations; thus, normal tissues may also be affected by the therapy and may contribute to specific nutritional problems. Impaired nutrition due to anorexia, mucositis, nausea, vomiting, and diarrhea may be dependent upon the specific chemotherapeutic agent, dose, or schedule utilized. Similar side effects from radiation therapy depend upon the dose, fractionation, and volume irradiated. When combined modality treatment is given the nutritional consequences may be magnified. Prospective, randomized clinical trials are underway to investigate the efficacy of nutritional support during chemotherapy-radiotherapy on tolerance to treatment, complications from treatment, and response rates to treatment. Preliminary results demonstrate that the administration of total parenteral nutrition is successful in maintaining weight during radiation therapy and chemotherapy, but that weight loss occurs after discontinuation of nutritional support. Thus, longterm evaluation is mandatory to learn the impact of nutritional support on survival, diease-free survival, and complication rates, as well as on the possible prevention of morbidity associated with aggressive chemotherapy-radiation therapy

  4. Movie prediction of lung tumor for precise chasing radiation therapy

    International Nuclear Information System (INIS)

    In recent years, precision for radiation therapy is a major challenge in the field of cancer treatment. When it comes to a moving organ like lungs, limiting the radiation to the target and sparing the surrounding healthy tissue is always a concern. It can induce the limit in the accuracy of area irradiated during lung cancer radiation therapy. Many methods have been introduced to compensate the motion in order to reduce the effect of radiation to healthy tissue due to respiratory motion. The motion of lung along with the tumor makes it very difficult to spare the healthy tissue during radiation therapy. The fear of this unintended damage to the neighboring tissue often limits the dose that can be applied to the tumor. The purpose of this research is the prediction of future motion images for the improvement of tumor tracking method. We predict the motion images by using principal component analysis (PCA) and multi-channel singular spectral analysis (MSSA) method. Time series x-ray images are used as training images. The motion images were successfully predicted and verified using the developed algorithm. The real time implementation of this method in future is believed to be significant for higher level of real time tumor tracking during radiation therapy. (author)

  5. Predicting Radiation Pneumonitis After Stereotactic Ablative Radiation Therapy in Patients Previously Treated With Conventional Thoracic Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu Hui; Zhang Xu [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Vinogradskiy, Yevgeniy Y. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Swisher, Stephen G. [Department of Thoracic and Cardiovascular Surgery, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Komaki, Ritsuko [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)

    2012-11-15

    Purpose: To determine the incidence of and risk factors for radiation pneumonitis (RP) after stereotactic ablative radiation therapy (SABR) to the lung in patients who had previously undergone conventional thoracic radiation therapy. Methods and Materials: Seventy-two patients who had previously received conventionally fractionated radiation therapy to the thorax were treated with SABR (50 Gy in 4 fractions) for recurrent disease or secondary parenchymal lung cancer (T <4 cm, N0, M0, or Mx). Severe (grade {>=}3) RP and potential predictive factors were analyzed by univariate and multivariate logistic regression analyses. A scoring system was established to predict the risk of RP. Results: At a median follow-up time of 16 months after SABR (range, 4-56 months), 15 patients had severe RP (14 [18.9%] grade 3 and 1 [1.4%] grade 5) and 1 patient (1.4%) had a local recurrence. In univariate analyses, Eastern Cooperative Oncology Group performance status (ECOG PS) before SABR, forced expiratory volume in 1 second (FEV1), and previous planning target volume (PTV) location were associated with the incidence of severe RP. The V{sub 10} and mean lung dose (MLD) of the previous plan and the V{sub 10}-V{sub 40} and MLD of the composite plan were also related to RP. Multivariate analysis revealed that ECOG PS scores of 2-3 before SABR (P=.009), FEV1 {<=}65% before SABR (P=.012), V{sub 20} {>=}30% of the composite plan (P=.021), and an initial PTV in the bilateral mediastinum (P=.025) were all associated with RP. Conclusions: We found that severe RP was relatively common, occurring in 20.8% of patients, and could be predicted by an ECOG PS score of 2-3, an FEV1 {<=}65%, a previous PTV spanning the bilateral mediastinum, and V{sub 20} {>=}30% on composite (previous RT+SABR) plans. Prospective studies are needed to validate these predictors and the scoring system on which they are based.

  6. 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.

  7. Imaging and Data Acquisition in Clinical Trials for Radiation Therapy.

    Science.gov (United States)

    FitzGerald, Thomas J; Bishop-Jodoin, Maryann; Followill, David S; Galvin, James; Knopp, Michael V; Michalski, Jeff M; Rosen, Mark A; Bradley, Jeffrey D; Shankar, Lalitha K; Laurie, Fran; Cicchetti, M Giulia; Moni, Janaki; Coleman, C Norman; Deye, James A; Capala, Jacek; Vikram, Bhadrasain

    2016-02-01

    Cancer treatment evolves through oncology clinical trials. Cancer trials are multimodal and complex. Assuring high-quality data are available to answer not only study objectives but also questions not anticipated at study initiation is the role of quality assurance. The National Cancer Institute reorganized its cancer clinical trials program in 2014. The National Clinical Trials Network (NCTN) was formed and within it was established a Diagnostic Imaging and Radiation Therapy Quality Assurance Organization. This organization is Imaging and Radiation Oncology Core, the Imaging and Radiation Oncology Core Group, consisting of 6 quality assurance centers that provide imaging and radiation therapy quality assurance for the NCTN. Sophisticated imaging is used for cancer diagnosis, treatment, and management as well as for image-driven technologies to plan and execute radiation treatment. Integration of imaging and radiation oncology data acquisition, review, management, and archive strategies are essential for trial compliance and future research. Lessons learned from previous trials are and provide evidence to support diagnostic imaging and radiation therapy data acquisition in NCTN trials.

  8. 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

  9. Adaptive response induced by occupational exposures to ionizing radiation

    International Nuclear Information System (INIS)

    We have found a significant decreased sensitivity to the cytogenetic effects of ionizing radiation (IR) and bleomycin (BLM) in lymphocytes from individuals occupationally exposed to IR when compared with a control population. These results suggest that occupational exposures to IR can induce adaptive response that can be detected by a subsequent treatment by IR or by BLM. However, no correlation between the results obtained with both treatments was observed. A great heterogeneity in the frequencies of chromatid aberrations induced by BLM was observed. The study of the influence of different harvesting times showed that there was no correlation with the frequencies of chromatid breaks. Our results indicate that the use of BLM to detect adaptive response has several difficulties at the individual level. (author)

  10. 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.

  11. 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. PMID:19753428

  12. Selective use of radiation therapy for neoplasms of the skin

    Energy Technology Data Exchange (ETDEWEB)

    Parker, R.G.

    1980-07-01

    Radiation therapy is preferable treatment for a minority of basal cell and epidermoid carcinomas of the skin. Proper use exploits the inherent advantage of preservation of function and cosmesis. Therefore, many cancers involving the eyelid, canthus, nose, nasolabial fold, pinna, ear canal, vermilion surface of the lower lip and skin of the chin can be advantageously treated by radiation therapy as compared to surgery, if pretreatment destruction of normal tissue is minimal. Although irradiation is equally effective, surgery is more expeditious for small lesions and cancers at other sites, which can be excised and followed by primary closure, and for large lesions if reconstruction will be required after destruction of the tumor. Radiation therapy can be effective, and usually is preferable treatment, for several other primary neoplasms of skin such as mycosis fungoides and Kaposi's sarcoma.

  13. State of research and perspective on adaptive response to low doses of ionizing radiation in Japan

    International Nuclear Information System (INIS)

    In a review article entitled ''Physical Benefits from Low Levels of Ionizing Radiation,'' published in Health Physics in December of 1982, Professor T.D. Luckey of the University of Missouri, asserted the ''radiation hormesis'' with 200 references. This resulted in the first International Symposium on Radiation Hormesis in Oakland, California (August 1985). CRIEPI consulted many specialists about Luckey's paper and studied many other papers such as Lorenz, 1954; Luckey, 1980, Liu et al., 1985. Radiation hormesis research in Japan has been based on the rationale that if Luckey's claim were to be true, radiation management in Japan has been extremely erroneous. CRIEPI organized a Hormesis Research Steering Committee composed of leading specialists in the field concerned, and began research in cooperation with a number of universities, as well as the National Cancer Research Institute, and the National Institute of Radiological Sciences. After obtaining interesting results in various experiments on the health effects of exposure to low doses of radiation, we have proceeded on an expanded program, which involves fourteen universities and two research institutes throughout Japan. The interesting results we obtained can be categorized in five groups. 1. Enhancement of immune systems such as lymphocytes and suppression of cancer, 2. Radio-adaptive response relating to the activation of DNA repair and adoptosis, 3. Rejuvenation of cells such as increase of SOD and cell membrane permeability, 4. Radiation effect on neuro-transmitting system through increase of key enzymes, 5. Others, including the therapy of adult-disease such as diabetes and hypertension. We are now carrying out experimental activities on the effects of low-dose radiation on mammals. After several years of research activities, we are recognizing Luckey's claim. Some basic surveys including Hiroshima Nagasaki and animal experiments in Japan have brought us valuable informations on the health effects of low

  14. 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)

  15. Combination of radiation injuries: pathogenesis, clinic, therapy

    International Nuclear Information System (INIS)

    Modern notions on combined radiation injuries (CRI) are presented. Characteristic of injurious factors of nuclear explosion and common regularities of the CRI origination is given. The data on the CRI clinical peculiarities, diagnostics and treatment, principles of medical assistance for the injured on the stages of medical evacuation and recommendations on rehabilitation are presented

  16. Radiation therapy for primary central nervous system lymphoma

    Directory of Open Access Journals (Sweden)

    Yuta Shibamoto

    2013-09-01

    Full Text Available Up until the late 1970s, radiation therapy played an important role in the treatment of primary central nervous system lymphoma (PCNSL but more recently its role has changed due to the increased use of systemic chemotherapy. In this article, the current status of radiotherapy for PCNSL and optimal forms of radiotherapy, including the treatment volume and radiation dose, are discussed. Data from nationwide Japanese surveys of PCNSL patients treated with radiation therapy suggest that the prognosis of PCNSL patients improved during the 1990s, in part due to the use of high-dose methotrexate-containing chemotherapy. The prognosis of patients treated with radiation alone also improved. Radiotherapy still seems to play an important role in the attempt to cure this disease.

  17. The Role for Radiation Therapy in the Management of Sarcoma.

    Science.gov (United States)

    Leachman, Brooke K; Galloway, Thomas J

    2016-10-01

    Although there is no consensus regarding the optimal sequencing of external beam radiotherapy and surgery for extremity soft tissue sarcoma, radiation therapy delivered before or after limb-sparing surgery significantly improves local control, particularly for high-grade tumors. Large database analyses suggest that improved local control may translate into an overall survival benefit. Best practices require ample communication between the radiation and surgical teams to ensure appropriate tissues are targeted, unnecessary radiation is avoided, and patients are afforded the best opportunity for cure while maintaining function. Modern experiences with intensity-modulated radiotherapy/image-guided radiation therapy suggest toxicity is reduced through field size reduction and precise targeting, improving the therapeutic ratio. PMID:27542646

  18. 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...

  19. Tracheoinnominate artery fistula as a complication of radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Reiter, D.; Piccone, B.R.; Littman, P.; Lisker, S.A.

    1979-03-01

    Tracheoinnominate artery fistulization is a well-known complication of tracheostomy and of tracheal resection. The first known occurrence of this problem in a patient in whom no transtracheal procedure had ever been performed is reported, and high-dose radiation therapy delivered three years before for a mediastinal malignancy is suggested as the cause. No evidence of tumor was found in or adjacent to the tracheovascular communication. The tracheoinnominate artery fistula must be considered a potential complication of radiation therapy as well as of surgery.

  20. Carcinoma of the maxillary antrum: surgery or radiation therapy

    International Nuclear Information System (INIS)

    Between the years 1968 and 1978, 57 patients with malignant tumors of the para-nasal sinuses were seen at the Medical College of Virginia. Thirty-nine patients presenting with squamous cell epitheliomas of the maxillary antrum, free of lymph node or distant metastases, and primarily treated at the Medical College of Virginia, form the basis of this study. Nineteen patients underwent radical craniofacial surgery with orbital exenteration and reconstruction. Twenty patients underwent Caldwell-Luc procedure followed by radical radiation therapy. The crude 3 year disease-free survivals are 50% and 37% in the radiation therapy and the surgery group, respectively. Local control, survival, and patterns of failure are discussed

  1. 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

  2. Anonymization of DICOM Electronic Medical Records for Radiation Therapy

    OpenAIRE

    Newhauser, Wayne; Jones, Timothy; Swerdloff, Stuart; Newhauser, Warren; Cilia, Mark; Carver, Robert (British painter, ca.1730-1791); Halloran, Andy; Zhang, Rui

    2014-01-01

    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 can...

  3. The radiation therapy of benign diseases

    International Nuclear Information System (INIS)

    X-ray should only be applied when other forms of treatment of good-natured diseases do not provide equally good results. One should note that somatic lesion should be completely avoided and genetic lesion avoided to the greatest probability. One can distinguish according to ones aims between inflammation irradiation, pain irradiation, stimulation therapy and functional therapy. An indication for inflammation irradiation can be post-operative parotitis, furuncle in the face, mastitis puerperalis, panaritium ossale, recurrent sudoriparouns abscesses and repelling reactions after transplanting organs. Pain irradiation is indicated with degenerative diseases of the skeleton system. A further possible application is radiotherapy of hypotrophic processes and benign tumours. Functional radiotherapy is indicated with hyperendocrinism, neurovegetative disorders and allergies. (MG)

  4. Maxillary sinus carcinoma: result of radiation therapy

    International Nuclear Information System (INIS)

    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

  5. Stem cell-based therapies for acute radiation syndrome

    International Nuclear Information System (INIS)

    Exposure to high doses of ionizing radiation in the event of accidental or intentional incident such as nuclear/radiological terrorism can lead to debilitating injuries to multiple organs resulting in death within days depending on the amount of radiation dose and the quality of radiation. Unfortunately, there is not a single FDA-licensed drug approved against acute radiation injury. The RadStem Center for Medical Countermeasures against Radiation (RadStem CMGR) program at Einstein is developing stem cell-based therapies to treat acute radiation syndrome (ARS). We have demonstrated that intravenous transplantation of bone marrow-derived and adipose-derived stromal cells, consisting of a mixture of mesenchymal, endothelial and myeloid progenitors can mitigate mice exposed to whole body irradiation of 12 Gy or whole abdominal irradiation of up to 20 Gy. We identified a variety of growth and differentiation factors that individually is unable to improve survival of animals exposed to lethal irradiation, but when administered sequentially mitigates radiation injury and improves survival. We termed this phenomenon as synthetic survival and describe a new paradigm whereby the 'synthetic survival' of irradiated tissues can be promoted by systemic administration of growth factors to amplify residual stem cell clonogens post-radiation exposure, followed by a differentiation factor that favors tissue stem cell differentiation. Synthetic survival can be applied to mitigate lethal radiation injury in multiple organs following radiation-induced hematopoeitic, gastrointestinal and pulmonary syndromes. (author)

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

    DEFF Research Database (Denmark)

    Wilms, Inge Linda; Rytter, Hana Malá

    whether the PAT method can be executed with similar effect using a computer with a touch screen.   62 healthy subjects were subjected to two experimental conditions: 1) pointing out at targets using the original box, 2) pointing out at targets on a computer attached touch screen. In both conditions...... on the touch screen (indirect feedback), 2) the feedback was provided by seeing one's own pointing finger, with no graphical feedback on the computer screen (direct feedback).   The results show that it is possible to obtain similar aftereffects from PAT by using a computer method but only when providing......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...

  7. a New Mobile Electron Accelerator for Intra Operative Electron Radiation Therapy

    Science.gov (United States)

    Adrich, P.; Baczewski, A.; Baran, M.; Drabik, W.; Gryn, K.; Hanke, R.; Jakubowska, E.; Jankowski, E.; Kędzierski, G.; Kielar, N.; Kujawiński, Ł.; Kopeć, J.; Kosiński, K.; Kozioł, R.; Kraszewski, P.; Krawczyk, P.; Kulczycka, E.; Lalik, P.; Marczenko, M.; Masternak, A.; Misiarz, A.; Olszewski, J.; Ozon, K.; Pławski, E.; Polak, A.; Psonka, W.; Rutkowska, M.; Rzadkiewicz, J.; Sienkiewicz, Z.; Staszczak, M.; Swat, K.; Syntfeld-Każuch, A.; Terka, M.; Wasilewski, A.; Wilczek, J.; Wojciechowski, M.; Wójtowicz, M.; Wronka, S.; Wysocka-Rabin, A.; Zalewski, K.

    2014-02-01

    A demonstrator of a new, highly mobile, robotized linear electron accelerator for Intra Operative Electron Radiation Therapy (IOERT) is under construction at National Centre for Nuclear Studies. In an IOERT treatment, a high dose of electron radiation is delivered in a single fraction directly to an exposed location after tumor ablation during oncological surgery. Due to the fact that the tumor can be located anywhere in the body, a high maneuverability of the accelerator and its adaptability to anatomical conditions are required. Moreover, since the treatment is usually executed in an unshielded operation room, the radiation protection issues are of principal importance. To assure safety of the patient and medical personnel, the therapeutic head is designed to constrain the radiation to the volume of the tumor lodge while minimizing leakage and stray radiation. For these reasons, construction of accelerators for IOERT differs considerably from the construction of linear electron accelerators for external beam radiation therapy. This paper presents some challenges and solutions in construction of the accelerator and in particular its therapeutic head with beam forming system.

  8. 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.

  9. Influential Factors and Synergies for Radiation-Gene Therapy on Cancer

    OpenAIRE

    Mei Lin; Junxing Huang; Yujuan Shi; Yanhong Xiao; Ting Guo

    2015-01-01

    Radiation-gene therapy, a dual anticancer strategy of radiation therapy and gene therapy through connecting radiation-inducible regulatory sequence to therapeutic gene, leading to the gene being induced to express by radiation while radiotherapy is performed and finally resulting in a double synergistic antitumor effect of radiation and gene, has become one of hotspots in the field of cancer treatment in recent years. But under routine dose of radiation, especially in the hypoxia environment ...

  10. Conserved sex chromosomes across adaptively radiated Anolis lizards.

    Science.gov (United States)

    Rovatsos, Michail; Altmanová, Marie; Pokorná, Martina; Kratochvíl, Lukáš

    2014-07-01

    Vertebrates possess diverse sex-determining systems, which differ in evolutionary stability among particular groups. It has been suggested that poikilotherms possess more frequent turnovers of sex chromosomes than homoiotherms, whose effective thermoregulation can prevent the emergence of the sex reversals induced by environmental temperature. Squamate reptiles used to be regarded as a group with an extensive variability in sex determination; however, we document how the rather old radiation of lizards from the genus Anolis, known for exceptional ecomorphological variability, was connected with stability in sex chromosomes. We found that 18 tested species, representing most of the phylogenetic diversity of the genus, share the gene content of their X chromosomes. Furthermore, we discovered homologous sex chromosomes in species of two genera (Sceloporus and Petrosaurus) from the family Phrynosomatidae, serving here as an outgroup to Anolis. We can conclude that the origin of sex chromosomes within iguanas largely predates the Anolis radiation and that the sex chromosomes of iguanas remained conserved for a significant part of their evolutionary history. Next to therian mammals and birds, Anolis lizards therefore represent another adaptively radiated amniote clade with conserved sex chromosomes. We argue that the evolutionary stability of sex-determining systems may reflect an advanced stage of differentiation of sex chromosomes rather than thermoregulation strategy. PMID:24433436

  11. Radiation therapy. 1990-2001. International Atomic Energy Agency publications

    International Nuclear Information System (INIS)

    This catalog lists all sales publications of the International Atomic Energy Agency dealing with Radiation Therapy, and issued during the period 1 January 1990 - 30 April 2001. Most publications are issued in English, though some are also available in other languages. These are noted in the catalogue

  12. Factors influencing radiation therapy student clinical placement satisfaction

    International Nuclear Information System (INIS)

    Introduction: Radiation therapy students at Queensland University of Technology (QUT) attend clinical placements at five different clinical departments with varying resources and support strategies. This study aimed to determine the relative availability and perceived importance of different factors affecting student support while on clinical placement. The purpose of the research was to inform development of future support mechanisms to enhance radiation therapy students’ experience on clinical placement. Methods: This study used anonymous Likert-style surveys to gather data from years 1 and 2 radiation therapy students from QUT and clinical educators from Queensland relating to availability and importance of support mechanisms during clinical placements in a semester. Results: The study findings demonstrated student satisfaction with clinical support and suggested that level of support on placement influenced student employment choices. Staff support was perceived as more important than physical resources; particularly access to a named mentor, a clinical educator and weekly formative feedback. Both students and educators highlighted the impact of time pressures. Conclusions: The support offered to radiation therapy students by clinical staff is more highly valued than physical resources or models of placement support. Protected time and acknowledgement of the importance of clinical education roles are both invaluable. Joint investment in mentor support by both universities and clinical departments is crucial for facilitation of effective clinical learning

  13. 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.

  14. Pregnancy after radiation therapy for carcinoma of the cervix.

    Science.gov (United States)

    Browde, S; Friedman, M; Nissenbaum, M

    1986-01-01

    A successful pregnancy after intracavitary radiation therapy for carcinoma of the cervix is described. An additional 13 similar cases from the literature are reviewed. The possible reasons for the occurrence of these pregnancies despite irradiation to the ovaries, cervical canal and endometrium are discussed. The fact is emphasized that no genetic damage to the child was expected.

  15. Radiation therapy for portal venous invasion by hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Keiichi Nakagawa; Masatoshi Makuuchi; Kuni Ohtomo; Hideomi Yamashita; Kenshiro Shiraishi; Naoki Nakamura; Masao Tago; Hiroshi Igaki; Yoshio Hosoi; Shuichiro Shiina; Masao Omata

    2005-01-01

    AIM: To clarify the efficacy and safety of three-dimensional conformal radiotherapy (3-D CRT) for this disease and to specify patient subgroups suitable for this treatment.METHODS: Fifty-two patients with HCC received PVI-targeted radiation therapy from January 1995 through December 2003. Portal venous invasion (PVI) was found in the second or lower order branches of the portal vein in 6 patients, in the first branch in 24 patients and in the main trunk in 22 patients. Child classifications of liver function before radiation therapy were A, B, and C for 19, 24 and 2 patients, respectively. All patients received three-dimensional conformal radiotherapy with a total dose ranging from 39 to 60 Gy (57.0 Gy in average).RESULTS: Overall survival rates at 1, 2, 3, 4, and 5 years were 45.1%, 25.3%, 15.2%, 10.1%, and 5.1%, respectively. Univariate analysis revealed that Child status, the number of tumor foci, tumor type,transcatheter arterial embolization (TAE) after radiation therapy were statistically significant prognostic factors.Multivariate analysis showed that the number of tumor foci and TAE after radiation therapy were statistically significant.CONCLUSION: The results of this study strongly suggest the efficacy of 3-D CRT as treatment for PVI in HCC. 3-D CRT is recommended in combination with postradiation TAE for PVI of HCC with 5 tumor foci or less in the liver and with Child A liver function.

  16. Clinical Opportunities in Combining Immunotherapy with Radiation Therapy

    Directory of Open Access Journals (Sweden)

    Steven Eric Finkelstein

    2012-11-01

    Full Text Available Preclinical work in murine models suggests that local radiotherapy plus intratumoral syngeneic DC injection can mediate immunologic tumor eradication. Radiotherapy affects the immune response to cancer, besides the direct impact on the tumor cells, and other ways to coordinate immune modulation with radiotherapy have been explored. We review here the potential for immune mediated anticancer activity of radiation on tumors. This is mediated by antigen acquisition and presentation by dendritic cells, and through changes of lymphocytes’ activity. Recent work has implemented the combination of external beam radiation (EBRT with intratumoral injection of dendritic cells (DC. This included a pilot study of coordinated intraprostatic, autologous DC injection together with radiation therapy with five HLA-A2(+ subjects with high-risk, localized prostate cancer; the protocol used androgen suppression, external beam radiation therapy (25 fractions, 45 Gy, DC injections after fractions 5, 15, and 25, and then interstitial radioactive implant. Another was a phase II trial using neo-adjuvant cell death-inducing EBRT plus intra-tumoral DC in soft tissue sarcoma, to test if this would increase immune activity toward soft tissue sarcoma associated antigens. Clinical experience using radiation therapies combined with other systemic immune treatments are additionally surveyed, including use of investigational recombinant vaccinia and fowlpox, interleukin-2, toll like receptor 9 (TLR9 agonists and lymphocyte checkpoint inhibitors directed at PD1 and at CTLA4.

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

    International Nuclear Information System (INIS)

    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

  18. 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.

  19. Evaluation of neutron radiation field in carbon ion therapy

    Science.gov (United States)

    Xu, Jun-Kui; Su, You-Wu; Li, Wu-Yuan; Yan, Wei-Wei; Chen, Xi-Meng; Mao, Wang; Pang, Cheng-Guo

    2016-01-01

    Carbon ions have significant advantages in tumor therapy because of their physical and biological properties. In view of the radiation protection, the safety of patients is the most important issue in therapy processes. Therefore, the effects of the secondary particles produced by the carbon ions in the tumor therapy should be carefully considered, especially for the neutrons. In the present work, the neutron radiation field induced by carbon ions was evaluated by using the FLUKA code. The simulated results of neutron energy spectra and neutron dose was found to be in good agreement with the experiment data. In addition, energy deposition of carbon ions and neutrons in tissue-like media was studied, it is found that the secondary neutron energy deposition is not expected to exceed 1% of the carbon ion energy deposition in a typical treatment.

  20. Patterns of Failure for Pediatric Glioblastoma Multiforme Following Radiation Therapy.

    Science.gov (United States)

    Shabason, Jacob E; Sutton, David; Kenton, Owen; Guttmann, David M; Lustig, Robert A; Hill-Kayser, Christine

    2016-08-01

    Despite aggressive multimodal therapy for pediatric glioblastoma multiforme (GBM), patient survival remains poor. This retrospective review of patients with GBM aims to evaluate the patterns of failure after radiation therapy (RT). The study included 14 pediatric patients treated with RT at the Children's Hospital of Philadelphia from 2007 to 2015. With a median follow-up of 16.9 months, 13 (92.9%) developed recurrent disease. Of recurrences, nine (69.2%) were in-field, three (23.1%) were marginal, and one (7.7%) was distant. The majority of patients treated with adjuvant radiation failed in the region of high-dose RT, indicating the need for improvements in local therapy. PMID:27128519

  1. 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

  2. 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.

  3. Intensity-Modulated Radiation Therapy for Primary Brain Tumors

    Institute of Scientific and Technical Information of China (English)

    Zhong-min Wang

    2004-01-01

    Radiation therapy has been used to treat primary brain tumors as standard primary and/or adjunctive therapies for decades. It is difficult for conventional radiotherapy to deliver a lethal dose of radiation to the tumors while sparing surrounding normal brain due to complicated structures and multifunction in human brain. With the understanding of radiation physics and computer technology, a number of novel and more precise radiotherapies have been developed in recent years. Intensity modulated radiotherapy (IMRT) is one of these strategies. The use of IMRT in the treatment of primary brain tumors is being increasing nowadays. It shows great promise for some of primary brain tumors and also presents some problems, This review highlights current IMRT in the treatment of mainly primary brain tumors.

  4. Sensitometry in diagnostic radiology, radiation therapy, and nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Haus, A.G.; Rossmann, K.; Vyborny, C.; Hoffer, P.B.; Doi, K.

    The purpose of this paper is to present a tutorial discussion on the sensitometric methods employed for determining the characteristic curve of interest in diagnostic radiology, radiation therapy, and nuclear medicine. These methods are based on the way in which various recording systems are exposed in practice. In diagnostic radiology, an inverse-square sensitometer is used for measurements of the characteristic curves of conventional film and screen-film systems. In radiation therapy, a sensitometric technique can be used for the determination of the proper characteristic curve for a film which can be placed beneath the patient before radiation treatment and removed afterwards so that an image of the anatomy actually irradiated is obtained. In nuclear medicine, a sensitometric study served as a means of evaluating several radiographic films for imaging of the light output on an oscilloscope when the Anger camera is used.

  5. Backgrounds of computer-assisted treatment planning in radiation therapy

    International Nuclear Information System (INIS)

    Interaction of ionising radiation and living materials causes biological damage of tempory or permanent nature. In radiation therapy this phenomenon is used in a controlled fashion in order to stop the proliferation of malignant cells, while at the same time limiting the permanent damage to healthy tissues and organs to at least tolerable levels. Because of the often relatively small differences in response of malignant growths and normal tissues, the margins between tolerable and intolerable are so small that the greatest precision in treatment planning and execution is required. The nature of this treatment agent implies that the radiation therapist has to rely very much on instrumentally obtained and processed information, in all phases of this medical activities around the patient. In this paper a description is given of the backgrounds of computer-assisted methods which have enabled modern individualised and optimised planning for therapy with high energy X- and gamma beams. (orig.)

  6. Study on neutron radiation field of carbon ions therapy

    CERN Document Server

    Xu, Jun-Kui; Li, Wu-Yuan; Yan, Wei-Wei; Chen, Xi-Meng; Mao, Wang; Pang, Cheng-Guo

    2015-01-01

    Carbon ions offer significant advantages for deep-seated local tumors therapy due to their physical and biological properties. Secondary particles, especially neutrons caused by heavy ion reactions should be carefully considered in treatment process and radiation protection. For radiation protection purposes, the FLUKA Code was used in order to evaluate the radiation field at deep tumor therapy room of HIRFL in this paper. The neutron energy spectra, neutron dose and energy deposition of carbon ion and neutron in tissue-like media was studied for bombardment of solid water target by 430MeV/u C ions. It is found that the calculated neutron dose have a good agreement with the experimental date, and the secondary neutron dose may not exceed one in a thousand of the carbon ions dose at Bragg peak area in tissue-like media.

  7. Protection Strategy of Sensitive Body Organs in Radiation Therapy

    CERN Document Server

    Abolfath, Ramin M

    2009-01-01

    In this paper, we investigate protection strategies of sensitive body anatomy against the irradiation to the cancerous moving tumors in intensity modulated radiation therapy. Inspired by optimization techniques developed in statistical physics and dynamical systems, we deploy a method based on variational principles and formulate an efficient genetic algorithm which enable us to search for global minima in a complex landscape of irradiation dose delivered to the radiosensitive organs at risk. We take advantage of the internal motion of body anatomy during radiation therapy to reduce the unintentional delivery of the radiation to sensitive organs. We show that the accurate optimization of the control parameters, compare to the conventional IMRT and widely used delivery based on static anatomy assumption, leads to a significant reduction of the dose delivered to the organs at risk.

  8. Salvage radiation therapy following radical prostatectomy

    DEFF Research Database (Denmark)

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

    2016-01-01

    BACKGROUND: The purpose of this observational cohort study was to evaluate the outcome and prognostic factors following salvage radiotherapy (SRT) in a consecutive national cohort. MATERIAL AND METHODS: Between 2006 and 2010, 259 patients received SRT in Denmark. Patient- and cancer-related chara......BACKGROUND: The purpose of this observational cohort study was to evaluate the outcome and prognostic factors following salvage radiotherapy (SRT) in a consecutive national cohort. MATERIAL AND METHODS: Between 2006 and 2010, 259 patients received SRT in Denmark. Patient- and cancer.......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...

  9. Clinical trial experience using erythropoietin during radiation therapy

    International Nuclear Information System (INIS)

    Oncologists have several reasons for trying to maintain or increase hemoglobin levels in their patients during therapy. Relief of the symptoms of anemia, including fatigue and dyspnea, are traditional, well-accepted indications. A newer rationale is to enhance the efficacy of radiation therapy and/or chemotherapy in controlling tumors. A laboratory animal study found that administration of recombinant human erythropoietin (rHuEPO) increased intratumoral median oxygen levels and diminished the proportion of measurements in the very low (<3 mm Hg) range. Hemoglobin level is a strong independent prognostic factor for tumor control by radiation therapy. The hemoglobin level at the end of radiation therapy is a stronger prognostic factor than is the hemoglobin level at the start of therapy. Numerous clinical trials have utilized rHuEPO during radiation with or without concurrent chemotherapy. All 4 trials which enrolled patients with low hemoglobin levels (<12 to 13.5 g/dl) found that rHuEPO significantly increased hemoglobin within 2 weeks and that hemoglobin levels continued to rise until the end of rHuEPO treatment. rHuEPO was efficacious in limiting the decrease in hemoglobin and use of packed red blood cell transfusion in the one reported trial in which it was used in patients with initially normal hemoglobin levels during intensive concurrent radiation and chemotherapy. One trial found a statistically significant improvement in complete pathologic response rate after neoadjuvant chemoradiotherapy with the use of rHuEPO. rHuEPO has a potentially large role to play in the care of the cancer patient. (orig.)

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

    International Nuclear Information System (INIS)

    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)

  11. 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)

  12. Intensity Modulated Radiation Therapy in Prostate Cancer

    International Nuclear Information System (INIS)

    Full text: Objective: To analyze the feasibility of high dose assessing acute and late toxicities both rectal and genitourinary in patients with clinically localized prostate cancer. Material and methods: Between April 2006 and April 2008 90 patients diagnosed with clinically localized prostate cancer were treated with MRT technique in the Department of Radiotherapy. The analysis included 80 patients, 10 of them in treatment. The total dose received was 80 Gy. One patient received 70.2 Gy (because of previous pelvic radiotherapy). Age average: 65 (r 43-85 years). Stage: T1c: 43 p (53.75%), T2: 35 p (43.75%), T3: 1 p (1.25%). Score of Gleason 10 ng/ml and < ng / ml: 7 (8.75%). Hormone therapy: 34 p (42.5%). Results: Acute rectal toxicity: grade 0: 46 p (57.5%), grade 1: 23 p (28.75%), grade 2: 9 p (11.25%), grade 3: 1 p (1.25%). Acute genitourinary toxicity: Grade 0: 26 p (32.5%) Grade 1: 36 p (45%), Grade 2: 17 p (21.25%), Grade 3: 1 p (1.25%). Chronic toxicity (RTOG) (considering patients evaluated more than 6 months after the end of treatment): 19 patients showed no rectitis and 1 patient had mild symptoms. Urethritis: 19 patients had no symptoms, 1 patient grade 1. The PSA pretreatment average: 9.5 ng / ml (80 p). One month after treatment: 4.6 ng / ml. With an average follow-up of 8 m (r 2-22), there were no biochemical recurrence. One patient had bone metastases one year after the end of the treatment. No deaths for prostate cancer were noticed. Conclusions: IMRT is a safe and effective therapy with more precision than the 3D-CRT, which allows increase the dose without increasing the risk of complications. (authors)

  13. [Stereotactic body radiation therapy for spinal metastases].

    Science.gov (United States)

    Pasquier, D; Martinage, G; Mirabel, X; Lacornerie, T; Makhloufi, S; Faivre, J-C; Thureau, S; Lartigau, É

    2016-10-01

    After the liver and lungs, bones are the third most common sites of cancer metastasis. Palliative radiotherapy for secondary bone tumours helps relieve pain, improve the quality of life and reduce the risk of fractures. Stereotactic body radiotherapy can deliver high radiation doses with very tight margins, which has significant advantages when treating tumours close to the spinal cord. Strict quality control is essential as dose gradient at the edge of the spinal cord is important. Optimal schedule is not defined. A range of dose-fractionation schedules have been used. Pain relief and local control are seen in over 80%. Toxicity rates are low, although vertebral fracture may occur. Ongoing prospective studies will help clarify its role in the management of oligometastatic patients. PMID:27614511

  14. Stereotactic Body Radiation Therapy in Spinal Metastases

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Kamran A. [Mayo Medical School, College of Medicine, Mayo Clinic, Rochester, MN (United States); Stauder, Michael C.; Miller, Robert C.; Bauer, Heather J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Rose, Peter S. [Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN (United States); Olivier, Kenneth R. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Brinkmann, Debra H. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Laack, Nadia N., E-mail: laack.nadia@mayo.edu [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

    2012-04-01

    Purpose: Based on reports of safety and efficacy, stereotactic body radiotherapy (SBRT) for treatment of malignant spinal tumors was initiated at our institution. We report prospective results of this population at Mayo Clinic. Materials and Methods: Between April 2008 and December 2010, 85 lesions in 66 patients were treated with SBRT for spinal metastases. Twenty-two lesions (25.8%) were treated for recurrence after prior radiotherapy (RT). The mean age of patients was 56.8 {+-} 13.4 years. Patients were treated to a median dose of 24 Gy (range, 10-40 Gy) in a median of three fractions (range, 1-5). Radiation was delivered with intensity-modulated radiotherapy (IMRT) and prescribed to cover 80% of the planning target volume (PTV) with organs at risk such as the spinal cord taking priority over PTV coverage. Results: Tumor sites included 48, 22, 12, and 3 in the thoracic, lumbar, cervical, and sacral spine, respectively. The mean actuarial survival at 12 months was 52.2%. A total of 7 patients had both local and marginal failure, 1 patient experienced marginal but not local failure, and 1 patient had local failure only. Actuarial local control at 1 year was 83.3% and 91.2% in patients with and without prior RT. The median dose delivered to patients who experienced local/marginal failure was 24 Gy (range, 18-30 Gy) in a median of three fractions (range, 1-5). No cases of Grade 4 toxicity were reported. In 1 of 2 patients experiencing Grade 3 toxicity, SBRT was given after previous radiation. Conclusion: The results indicate SBRT to be an effective measure to achieve local control in spinal metastases. Toxicity of treatment was rare, including those previously irradiated. Our results appear comparable to previous reports analyzing spine SBRT. Further research is needed to determine optimum dose and fractionation to further improve local control and prevent toxicity.

  15. Complementary strategies for the management of radiation therapy side effects.

    Science.gov (United States)

    Stubbe, Christine E; Valero, Meighan

    2013-07-01

    Patients with cancer utilize complementary and alternative medicine (CAM) for a variety of purposes, one of which is the reduction of side effects of conventional treatment. With a large number of their patients using CAM, it is important for advanced practitioners in oncology to have an understanding of these therapies to better guide their patients. Side effects of radiation therapy that may have dose-limiting poten-tial include diarrhea, mucositis, skin toxicity, and xerostomia. A com-mon side effect that is not necessarily dose-limiting but considerably troublesome to patients is cancer- and treatment-related fatigue. The CAM therapies that may alleviate some of the side effects of radiation therapy include probiotics, psyllium, exercise, melatonin, honey, acu-puncture, and calendula. Therapies that require more research or have been shown to be ineffective include aloe vera, glutamine, and deglyc-yrrhizinated licorice. This article provides an overview of these thera-pies as well as related research and analysis. PMID:25032003

  16. Adaptation of the present concept of dosimetric radiation protection quantities for external radiation to radiation protection practice

    International Nuclear Information System (INIS)

    The present concept of dosimetric radiation protection quantities for external radiation is reviewed. For everyday application of the concept some adaptations are recommended. The check of the compliance with dose limits should be performed either by the comparison with values of the respective operational quantities directly or by the calculation of the protection quantity by means of the operational quantity, the appertaining conversion coefficient and additional information of the radiation field. Only four operational quantities are regarded to be sufficient for most applications in radiation protection practice. The term equivalent should be used in the connection dose equivalent only. Proposals are made for names of frequently used operational quantities which are denoted up to now by symbols only. (authors)

  17. Pulmonary function tests after radiation therapy following pneumonectomy

    International Nuclear Information System (INIS)

    Radiation is often necessary after pneumonectomy, either immediately or due to local cancer recurrence. High radiation doses represent a challenge due to the limited tolerance of the necessity of preserving and protecting the remaining lung parenchyma. The use of CT scan based-treatment planning allows delivery of high radiation doses. To evaluate the radiation tolerance of the lung after high radiation dose, we compared pulmonary function tests performed before surgery and after radiation therapy. Ten male patients (mean age, 56 years old; age range, 45-73) were irradiated after pneumonectomy for lung cancer. All patients had a CT scan-based treatment planning. The mean radiation dose was 56 Gy (45-66 Gy) delivered with a linear accelerator and multiple complex fields. Two or more sets of pulmonary function tests were available (before surgery and 2 to 6 months after radiation). No patient developed clinical radiation pneumonitis and most of the patients had a minimal para-mediastinal fibrosis at CT scan. Postirradiation pulmonary lung tests were compared to the theoretical values of the estimated defect observed after pneumonectomy. No significant decrease in forced expiratory volume in 1s/inspiratory vital capacity (FEV1/IVC) was observed in ten evaluable patients; the observed values were comparable to those expected after pneumonectomy without irradiation (FEV1/IVC: 61 to 100%), showing that irradiation did not alter pulmonary function. Computerized tomography-based treatment planning and the use of complex beam positioning allowed optimal lung parenchymal preservation. Through this procedure, high doses of radiation can be delivered to the mediastinum and bed tumor. Comparison of pulmonary function tests performed before surgery and after radiation showed no alteration of lung function, even after high doses. Optimal tools required for the evaluation of radiation on lung parenchyma are still to be defined. (authors)

  18. Radiation therapy in the treatment of aggressive fibromatoses (desmoid tumors).

    Science.gov (United States)

    Kiel, K D; Suit, H D

    1984-11-15

    Twenty-five patients with aggressive fibromatoses (desmoid tumors) have been treated or followed in the Department of Radiation Medicine at the Massachusetts General Hospital between 1972 and 1982. Seventeen patients were treated by radiation, 4 for primary and 13 for recurrent disease. Seven patients were treated in conjunction with surgery. Partial or complete regression was achieved in 76%, and 59% are without evidence of disease (NED) at 9 to 94 months follow-up. Eight of ten patients treated primarily with radiation have achieved complete response without an attempt at resection (five) or have achieved stabilization (three) of their disease after some regression. Consistent complete control was seen with doses above 60 Gy. Periods to 27 months were required to observe complete responses. Only three failures within the radiation field were observed, two after low doses (22 and 24 Gy, respectively). Eight patients were seen after resection but with uncertain or histologically minimum positive margins, and were followed regularly and not treated. One patient has failed to date and is NED after resection. Radiation therapy is recommended in those situations where wide-field resection without significant morbidity is not possible for gross local disease. If minimally positive margins exist after resection in a patient who may be followed carefully, frequent follow-up and prompt treatment at recurrence may be an effective alternative to immediate radiation therapy.

  19. Some computer graphical user interfaces in radiation therapy.

    Science.gov (United States)

    Chow, James C L

    2016-03-28

    In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls

  20. 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)

  1. 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.

  2. Hepatocellular Carcinoma Radiation Therapy: Review of Evidence and Future Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Klein, Jonathan [Department of Radiation Oncology, Princess Margaret Hospital/University of Toronto, Toronto, Ontario (Canada); Dawson, Laura A., E-mail: laura.dawson@rmp.uhn.on.ca [Department of Radiation Oncology, Princess Margaret Hospital/University of Toronto, Toronto, Ontario (Canada)

    2013-09-01

    Hepatocellular carcinoma (HCC) is a leading cause of global cancer death. Curative therapy is not an option for most patients, often because of underlying liver disease. Experience in radiation therapy (RT) for HCC is rapidly increasing. Conformal RT can deliver tumoricidal doses to focal HCC with low rates of toxicity and sustained local control in HCC unsuitable for other locoregional treatments. Stereotactic body RT and particle therapy have been used with long-term control in early HCC or as a bridge to liver transplant. RT has also been effective in treating HCC with portal venous thrombosis. Patients with impaired liver function and extensive disease are at increased risk of toxicity and recurrence. More research on how to combine RT with other standard and novel therapies is warranted. Randomized trials are also needed before RT will be generally accepted as a treatment option for HCC. This review discusses the current state of the literature and opportunities for future research.

  3. Late neuro endocrinological sequelae of radiation therapy

    International Nuclear Information System (INIS)

    When the hypothalamic-pituitary axis (HPA) is included in the treatment field in children and adults, a variety of neuroendocrine disturbances are more common than has been appreciated in the past. Clinical damage to the pituitary and thyroid glands usually occurs months to years after treatment, and is preceded by a long subclinical phase. Primary brain tumors represent the largest group of malignant solid tumors in children. The survival rates of 50 reported in the literature are achieved at the expense of late occurring effects. Radiation-induced abnormalities are generally dose-dependent. Growth hormone deficiency and premature sexual development can occur at doses as low as 18 Gy in conventional fractionation, and is the most common neuroendocrine problem in children. In patients treated with > 40 Gy on the HPA, deficiency of gonadotropins, thyroid stimulation hormone, and adrenocorticotropin (> 50 Gy), hyperprolactinemia can be seen, especially among young women. Most neuroendocrine disturbances that develop as a result of HPA can be treated efficiently, provided that an early detection of these endocrine dysfunctions abnormalities is done. (authors)

  4. Computer calculations in interstitial seed therapy: I. Radiation treatment planning

    International Nuclear Information System (INIS)

    Interstitial seed therapy computers can be used for radiation treatment planning and for dose control after implantation. In interstitial therapy with radioactive seeds there are much greater differences between planning and carrying out radiation treatment than in teletherapy with cobalt-60 or X-rays. Because of the short distance between radioactive sources and tumour tissue, even slight deviations from the planned implantation geometry cause considerable dose deviations. Furthermore, the distribution of seeds in an actual implant is inhomogeneous. During implantation the spatial distribution of seeds cannot be examined exactly, though X-rays are used to control the operation. The afterloading technique of Henschke allows a more exact implantation geometry, but I have no experience of this method. In spite of the technical difficulty of achieving optimum geometry, interstitial therapy still has certain advantages when compared with teletherapy: the dose in the treated volume can be kept smaller than in teletherapy, the radiation can be better concentrated in the tumour volume, the treatment can be restricted to one or two operations, and localized inoperable tumours may be cured more easily. The latter may depend on an optimal treatment time, a relatively high tumour dose and a continuous exponentially decreasing dose rate during the treatment time. A disadvantage of interstitial therapy is the high personnel dose, which may be reduced by the afterloading technique of Henschke (1956). However, the afterloading method requires much greater personnel and instrumental expense than free implantation of radiogold seeds and causes greater trauma for the patient

  5. Postoperative radiation therapy for grade II and III intracranial ependymoma

    International Nuclear Information System (INIS)

    Purpose: To retrospectively determine the long-term outcome of intracranial ependymoma patients treated with surgery and postoperative radiation therapy. Methods and materials: Sixty patients were treated at our institution between 1964 and 2000. Forty patients had World Health Organization Grade II ependymoma, and 20 patients had Grade III ependymoma. The median patient age was 10.7 years. The majority of patients were male (55%), had infratentorial tumors (80%), and had subtotal resections (72%). Postoperative radiation therapy was delivered to all patients to a median total dose of 50.4 Gy. Craniospinal radiation therapy was used in the earlier era in only 12 patients (20%). Results: The median follow-up of surviving patients was 12.5 years. The 5-year and 10-year disease-free survival rates for all patients were 58.4% and 49.5%, respectively. The 5-year and 10-year overall survival rates for all patients were 71.2% and 55.0%, respectively. Supratentorial tumor location was independently associated with a worse disease-free survival. Subtotal resection and supratentorial location predicted a worse overall survival, but this failed to reach statistical significance. No statistically significant effect on prognosis was observed with tumor grade, patient age, or radiation dose or volume. Conclusion: Our long-term follow-up indicates that half of ependymoma patients will have disease recurrences, indicating the need for more effective treatments

  6. Vitamin A as an adjunct to radiation therapy of cancer

    International Nuclear Information System (INIS)

    In a series of animal experiments supplemental Vitamin A (Vit. A) has been found to enhance the effectiveness of irradiation in tumor therapy in several ways: 1. By direct potentiation of radiation effects as manifested by hastening of tumor regression and lessening of metastatic spread. 2. By exerting a protective action against toxicity induced by therapeutic exposure to radiation as expressed by a) moderation of depletion of blood elements (i.e. leucopenia, thrombocytopenia) b) minimizing of damage to mucosal surfaces (i.e. radiation esophagitis) c) reduction of immunosuppression (i.e. increased rate of ''takes'' of transplanted tumors in irradiated animals) d) counteracting of carcinogenic effects (i.e. radiation-induced lymphoma). 3. By accelerating wound healing thereby shortening surgery to irradiation time in post-operative treatment. The above observations derived from their animal experiment which are described in detail suggest that Vit. A may be of value as an antineoplastic and radioprotective agent

  7. 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.

  8. 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.

  9. Gold Nanoparticles and Their Alternatives for Radiation Therapy Enhancement

    Science.gov (United States)

    Cooper, Daniel; Bekah, Devesh; Nadeau, Jay

    2014-10-01

    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.

  10. Advances in three-dimensional conformal radiation therapy physics with intensity modulation.

    Science.gov (United States)

    Webb, S

    2000-09-01

    Intensity-modulated radiation therapy, a specific form of conformal radiation therapy, is currently attracting a lot of attention, and there are high expectations for this class of treatment techniques. Several new technologies are in development, but physicists are still working to improve the physical basis of radiation therapy.

  11. 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. 892.5050 Section 892.5050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...-particle radiation therapy system. (a) Identification. A medical charged-particle radiation therapy...

  12. The Use of Medical Images in Planning and Delivery of Radiation Therapy

    OpenAIRE

    Kalet, Ira J; Austin-Seymour, Mary M.

    1997-01-01

    The authors provide a survey of how images are used in radiation therapy to improve the precision of radiation therapy plans, and delivery of radiation treatment. In contrast to diagnostic radiology, where the focus is on interpretation of the images to decide if disease is present, radiation therapy quantifies the extent of the region to be treated, and relates it to the proposed treatment using a quantitative modeling system called a radiation treatment planning (RTP...

  13. 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.)

  14. Radiation therapy for the prevention of postoperative and traumatic complications

    Energy Technology Data Exchange (ETDEWEB)

    Kishkovskij, A.N.; DudareV, A.L. (Voenno-Meditsinskaya Akademiya, Leningrad (USSR))

    1983-05-01

    An analysis of the results of radiation therapy of 587 patients with postoperative and traumatic complications has shown that special ..gamma..-therapy used at early time following trauma or surgical intervention, with the first clinical signs of an incipient inflammatory process (the so-called ''anticipating'' irradiation), makes it possible to avoid the development of serious postoperative, post-traumatic complications: wound suppuration, fistulas, secondary parotitis, postamputation pain syndrome, ''needle'' osteomyelitis, keloid cicatrix, skin graft rejection, etc. In the author opinion, this promising trend in radiotherapy of nontumorous diseases is worth a wider using in clinical practice.

  15. The radiation techniques of tomotherapy & intensity-modulated radiation therapy applied to lung cancer

    OpenAIRE

    Zhu, Zhengfei; Fu, Xiaolong

    2015-01-01

    Radiotherapy (RT) plays an important role in the management of lung cancer. Development of radiation techniques is a possible way to improve the effect of RT by reducing toxicities through better sparing the surrounding normal tissues. This article will review the application of two forms of intensity-modulated radiation therapy (IMRT), fixed-field IMRT and helical tomotherapy (HT) in lung cancer, including dosimetric and clinical studies. The advantages and potential disadvantages of these t...

  16. Shielding and Radiation Protection in Ion Beam Therapy Facilities

    Science.gov (United States)

    Wroe, Andrew J.; Rightnar, Steven

    Radiation protection is a key aspect of any radiotherapy (RT) department and is made even more complex in ion beam therapy (IBT) by the large facility size, secondary particle spectra and intricate installation of these centers. In IBT, large and complex radiation producing devices are used and made available to the public for treatment. It is thus the responsibility of the facility to put in place measures to protect not only the patient but also the general public, occupationally and nonoccupationally exposed personnel working within the facility, and electronics installed within the department to ensure maximum safety while delivering maximum up-time.

  17. Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma

    DEFF Research Database (Denmark)

    Ebbeskov Lauritsen, Liv; Meidahl Petersen, Peter; Daugaard, Gedske

    2012-01-01

    We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost....../or to the spinal cord. RT is believed to produce plexus injury by both direct toxic effects and secondary microinfarction of the nerves, but the exact pathophysiology of RT-induced injury is unclear. Since reported studies of radiation-induced neurological adverse effects are limited, it is difficult to estimate...

  18. Late complications of radiation therapy for patients with malignant lymphoma

    International Nuclear Information System (INIS)

    The improvement on the treatment of malignant lymphoma have led to prolonged survival for many patients. However, they are at risk of late complications of the disease and treatment. Impaired function due to radiation-induced injury of normal tissues, such as cardiac, pulmonary, or thyroid dysfunction, becoming manifest at few months to years after treatment. Fortunately, only a small portion of these are major complications, causing severe, or permanent disability. The frequency of secondary leukemia (AML) occurring in patients treated for malignant lymphoma is highest in those patients receiving many courses of combination chemotherapy and is low in those receiving radiation therapy alone. (author) 47 refs

  19. 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)

  20. The role of radiation therapy in the multidisciplinary treatment of patients with malignant tumors. Radiation pathological stand point

    International Nuclear Information System (INIS)

    Estimations suggest that about 60% of all cancer patients will require some form of radiation therapy during their lifetime. Although 40 to 50% of cancer patients in Europe and the United States receive radiation therapy, only about 20% of patients with cancer in Japan undergo such treatment. This is largely due to the lack of understanding of the role of radiation therapy by many medical personnel in Japan, as well as to ''''radiation allergy'''' among many of the general population in Japan, a country that has been undergone atomic bombing. From our perspective as specialists in radiation therapy, the chronic shortage of radiation oncologist also poses a serious problem. Although there are approximately 700 hospitals throughout Japan where radiation therapy is available, no more than half this number of medical facilities have a full-time radiation oncologist. Perhaps the reason for this is that radiation therapy is perceived as unnecessary in Japan. However, it is absolutely essential. In our experience, the 5-year relative survival rate of patients with malignant tumors who have undergone radiation therapy in our clinic is 65 percent. Thus, radiation therapy has proven very useful in the treatment of malignant tumors. Moreover, better estimates of prognosis of cancer patients treated with radiation therapy are becoming possible. This article discusses the role of radiation therapy, from a radiation pathological perspective, in a multidisciplinary approach to treatment of cancer patients. I also emphasize the critical importance of training radiation oncologists who can function as part of multidisciplinary teams that care for patients with malignant tumors. (author). 50 refs

  1. Image-guided radiation therapy:basic concepts and clinical potentials

    Institute of Scientific and Technical Information of China (English)

    Omar Abdel-Rahman

    2014-01-01

    The adaptation and integration of imaging into the process of cancer detection, diagnosis, and intervention is an area of medicine that is undergoing extremely rapid development. Radiation therapy is a prime example of this change. While the objectives of these developments are clear, they raise numerous issues regarding the skil s and resources that assure these technologies are appropriately integrated and applied. We wil explore the basic concepts related to image guidance in various radiotherapy-related procedures with special emphasis on the clinical potentials of this impressive technology.

  2. Impact of dose calculation algorithm on radiation therapy

    Institute of Scientific and Technical Information of China (English)

    Wen-Zhou; Chen; Ying; Xiao; Jun; Li

    2014-01-01

    The quality of radiation therapy depends on the ability to maximize the tumor control probability while minimizing the normal tissue complication probability.Both of these two quantities are directly related to the accuracy of dose distributions calculated by treatment planning systems.The commonly used dose calculation algorithms in the treatment planning systems are reviewed in this work.The accuracy comparisons among these algorithms are illustrated by summarizing the highly cited research papers on this topic.Further,the correlation between the algorithms and tumor control probability/normal tissue complication probability values are manifested by several recent studies from different groups.All the cases demonstrate that dose calculation algorithms play a vital role in radiation therapy.

  3. Conformal radiation therapy: technical requirements and clinical applications

    International Nuclear Information System (INIS)

    Conformal radiation therapy represents a considerable and attractive challenge in oncology. Its aim is mainly to improve local control by increasing the dose with an acceptable rate of complications. This work overviews the world literature on this subject. The technical and theoretical requirements are highlighted. These requirements include a precise definition of the target volume by digital imaging (essentially CT scan), but also clear view of the target volume and the organs at risk, a specific collimation of the beam, 3-D dose calculations, optimization procedures, and a rigid immobilization of the patient with verification of his position. Moreover, the clinical applications of conformal radiation therapy are reviewed and discussed. (authors). 80 refs., 1 tab

  4. Approaching Oxygen-Guided Intensity-Modulated Radiation Therapy.

    Science.gov (United States)

    Epel, Boris; Redler, Gage; Pelizzari, Charles; Tormyshev, Victor M; Halpern, Howard J

    2016-01-01

    The outcome of cancer radiation treatment is strongly correlated with tumor oxygenation. The aim of this study is to use oxygen tension distributions in tumors obtained using Electron Paramagnetic Resonance (EPR) imaging to devise better tumor radiation treatment. The proposed radiation plan is delivered in two steps. In the first step, a uniform 50% tumor control dose (TCD50) is delivered to the whole tumor. For the second step an additional dose boost is delivered to radioresistant, hypoxic tumor regions. FSa fibrosarcomas grown in the gastrocnemius of the legs of C3H mice were used. Oxygen tension images were obtained using a 250 MHz pulse imager and injectable partially deuterated trityl OX63 (OX71) spin probe. Radiation was delivered with a novel animal intensity modulated radiation therapy (IMRT) XRAD225Cx microCT/radiation therapy delivery system. In a simplified scheme for boost dose delivery, the boost area is approximated by a sphere, whose radius and position are determined using an EPR O2 image. The sphere that irradiates the largest fraction of hypoxic voxels in the tumor was chosen using an algorithm based on Receiver Operator Characteristic (ROC) analysis. We used the fraction of irradiated hypoxic volume as the true positive determinant and the fraction of irradiated normoxic volume as the false positive determinant in the terms of that analysis. The most efficient treatment is the one that demonstrates the shortest distance from the ROC curve to the upper left corner of the ROC plot. The boost dose corresponds to the difference between TCD90 and TCD50 values. For the control experiment an identical radiation dose to the normoxic tumor area is delivered.

  5. 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

  6. Wound healing after radiation therapy: Review of the literature

    International Nuclear Information System (INIS)

    Radiation therapy is an established modality in the treatment of head and neck cancer patients. Compromised wound healing in irradiated tissues is a common and challenging clinical problem. The pathophysiology and underlying cellular mechanisms including the complex interaction of cytokines and growth factors are still not understood completely. In this review, the current state of research regarding the pathomechanisms of compromised wound healing in irradiated tissues is presented. Current and possible future treatment strategies are critically reviewed

  7. 4D PET-CT guided radiation therapy

    OpenAIRE

    Geets, X

    2013-01-01

    Tremendous technological progress in the field of imaging and computation have been revolutionizing radiotherapy of non-small cell lung cancer (NSCLC). Tumor biology can now be characterized by functional imaging for modifying treatment management and dose delivered in better accordance with the radiobiology of solid tumors and normal tissues. Specific radiation therapy (RT) strategies can further address the tumor motion issue, ensuring optimal tumor coverage with small safety margins.

  8. Urethral strictures after radiation therapy for prostate cancer

    Science.gov (United States)

    Dal Pra, Alan; Furrer, Marc; Thalmann, George; Spahn, Martin

    2016-01-01

    Urethral stricture after radiation therapy for localized prostate cancer is a delicate problem as the decreased availability of tissue healing and the close relation to the sphincter complicates any surgical approach. We here review the pathophysiology, dosimetry, and the disease specific aspects of urethral strictures after radiotherapy. Moreover we discuss different treatment option such as direct vision internal urethrotomy as well as techniques for open reconstruction with and without tissue transfer.

  9. Radiation therapy of tumours of the central nervous system

    International Nuclear Information System (INIS)

    The aim of this work is to present the principles of radiation therapy of tumours of the central nervous system, according to the experience of the Institute of Oncology in Krakow. The text was designed primarily for the radiotherapists involved in the treatment of tumours of the central nervous system, and may be used as an auxiliary textbook for those preparing for the examination in radiotherapy. (author)

  10. [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

  11. Real-time motion-adaptive-optimization (MAO) in TomoTherapy

    Science.gov (United States)

    Lu, Weiguo; Chen, Mingli; Ruchala, Kenneth J.; Chen, Quan; Langen, Katja M.; Kupelian, Patrick A.; Olivera, Gustavo H.

    2009-07-01

    the proposed method is applicable for real-time motion compensation in TomoTherapy delivery. Extension of the method to real-time adaptive radiation therapy (ART) that compensates for all kinds of delivery errors was proposed. Further validation and clinical implementation is underway. For more information on this article see medicalphysicsweb.org

  12. Hybrid Adaptive Ray-Moment Method (HARM$^2$): A Highly Parallel Method for Radiation Hydrodynamics on Adaptive Grids

    CERN Document Server

    Rosen, Anna L; Oishi, Jeffrey S; Lee, Aaron T; Klein, Richard I

    2016-01-01

    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 (HARM$^2$) 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 $\\mathcal{O}(10^3)$ processors on distributed memory machines. We present a series of tests to demonstrate the accuracy and performance of the method.

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

    International Nuclear Information System (INIS)

    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

  14. 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.

  15. Osteoradionecrosis of the skull after radiation therapy for invasive carcinoma.

    Science.gov (United States)

    Nguyen, Michaela T; Billington, Alicia; Habal, Mutaz B

    2011-09-01

    Osteoradionecrosis (ORN) of the skull is a rare but fatal complication of radiation therapy for the treatment of head and neck malignancies. The pathogenesis of ORN follows the "3Hs Theory" proposed by Marx (J Oral Maxillofac Surg 1983;41:283-288) in which radiation induces tissue injury by causing vessel thrombosis (hypovascularity), which leads to hypoxia, and results in cell death of the skin and the underlying structure of the bony element (hypocellularity) including the deep visceral structures. This note details a patient with severe and extensive ORN of the parietooccipital region of the skull because of a large dose of radiation therapy for the treatment of an invasive basal cell carcinoma of the scalp. The patient's condition was further complicated by an extensive infection with methicillin-resistant Staphylococcus aureus, which leads to meningitis and cerebral edema as well as cerebritis. The patient was successfully treated with interdisciplinary medical and surgical aggressive therapy and radical procedures involving 4 separate trips to the operating room for an 18-month period. Success was achieved because of early clinical diagnosis of ORN, aggressive eradication of infected and necrotic tissues including the brain, and restoration of functioning and viable tissues through the use of local flaps to change an open wound to a closed wound. PMID:21959411

  16. Radiation Therapy in Malignant Tumors of the Parotid Gland

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Dong; Park, Charn Il; Kim, Kwang Hyun [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1994-02-15

    A retrospective analysis was performed on 55 patients with malignant parotid tumor who were treated with radiation therapy between March, 1979 and July, 1989. Of these patients, 8 patients received radiation therapy(RT) alone and 47 patients were treated with combined operation and radiation therapy(OP+RT). The follow-up period of the survivors ranged form 1 to 129 months with a median of 48 months. The common histologic types were mucoepidermoid carcinoma (25 cases), malignant mixed tumor(12 cases), adenoid cystic carcinoma(6 cases). The 5 and 10 year local control rate were 69.8% and 65.7% in all patients. In OP+RT group, prognostic factors related to local control were histologic grade, tumor size, lymph node metastasis. Resection of facial nerve did not affect the local control rate significantly(p=0.129). Distant metastasis developed in 23.6% of patients, mostly to the lung. Actuarial overall survival rate was 72.2% at 10 years and formed plateau after 5 years. Disease-free (NED) survival rate was 49.4% at 10 years and was better achieved in OP+RT group and low grade lesions. Based on our result, a well planned postoperative RT following parotidectomy is highly efficacious in controlling malignant tumors of the parotid gland and preservation of facial nerve.

  17. Role of radiation therapy in lung cancer management - a review.

    Science.gov (United States)

    Shi, J-G; Shao, H-J; Jiang, F-E; Huang, Y-D

    2016-07-01

    Lung cancer is the leading cause of cancer death worldwide. Furthermore, more than 50% of lung cancer patients are found affected by distant metastases at the time of diagnosis. On the other hand, 20% of these patients are without regional spread and are good candidates for surgical operation. The remaining 30% represent an intermediate group whose tumors have metastasized up to regional lymph nodes. These remain 30% are the most appropriate candidates for radiation therapy. These patients are also called as "locally advanced lung cancer" or stage III lung cancer patients. In these patients strategy of combination therapy viz. radiation therapy in combination with chemotherapy is also tried by various groups in the recent past for this better management. However, long-term survival is still poor with a 5-year survival in 5-25% of patients. During the last decades, there has been a development in radiation strategies. The present review article focuses on different approaches to optimize radiotherapy for these patients. PMID:27466995

  18. 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.

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

    International Nuclear Information System (INIS)

    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

  20. 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.

  1. Development of a remote proton radiation therapy solution over internet2.

    Science.gov (United States)

    Belard, Arnaud; Tinnel, Brent; Wilson, Steve; Ferro, Ralph; O'Connell, John

    2009-12-01

    Through our existing partnership, our research program has leveraged the benefits of proton radiation therapy through the development a robust telemedicine solution for remote proton therapy planning. Our proof-of-concept system provides a cost-effective and functional videoconferencing desktop platform for both ad-hoc and scheduled communication, as well as a robust interface for data collaboration (application-sharing of a commercial radiation treatment planning package). Over a 2-year period, our evaluation of this model has highlighted the inherent benefits of this affordable remote treatment planning solution, i.e., (1) giving physicians the ability to remotely participate in refining and generating proton therapy plans via a secure and robust Internet2 VPN tunnel to the University of Pennsylvania's commercial proton treatment planning package; (2) allowing cancer-care providers sending patients to a proton treatment facility to participate in treatment planning decisions by enabling referring or accepting providers to initiate ad-hoc, point-to-point communication with their counterparts to clarify and resolve issues arising before or during patient treatment; and thus (3) allowing stewards of an otherwise highly centralized resource the ability to encourage wider participation with and referrals to sparsely located proton treatment centers by adapting telemedicine techniques that allow sharing of proton therapy planning services. We believe that our elegant and very affordable approach to remote proton treatment planning opens the door to greater worldwide referrals to the scarce resource of proton treatment units and wide-ranging scientific collaboration, both nationally and internationally.

  2. Acute and Chronic Cutaneous Reactions to Ionizing Radiation Therapy.

    Science.gov (United States)

    Bray, Fleta N; Simmons, Brian J; Wolfson, Aaron H; Nouri, Keyvan

    2016-06-01

    Ionizing radiation is an important treatment modality for a variety of malignant conditions. However, development of radiation-induced skin changes is a significant adverse effect of radiation therapy (RT). Cutaneous repercussions of RT vary considerably in severity, course, and prognosis. When they do occur, cutaneous changes to RT are commonly graded as acute, consequential-late, or chronic. Acute reactions can have severe sequelae that impact quality of life as well as cancer treatment. Thus, dermatologists should be informed about these adverse reactions, know how to assess their severity and be able to determine course of management. The majority of measures currently available to prevent these acute reactions are proper skin hygiene and topical steroids, which limit the severity and decrease symptoms. Once acute cutaneous reactions develop, they are treated according to their severity. Treatments are similar to those used in prevention, but incorporate wound care management that maintains a moist environment to hasten recovery. Chronic changes are a unique subset of adverse reactions to RT that may develop months to years following treatment. Chronic radiation dermatitis is often permanent, progressive, and potentially irreversible with substantial impact on quality of life. Here, we also review the etiology, clinical manifestations, pathogenesis, prevention, and management of late-stage cutaneous reactions to radiotherapy, including chronic radiation dermatitis and radiation-induced fibrosis. PMID:27250839

  3. Aesthetic results following partial mastectomy and radiation therapy

    International Nuclear Information System (INIS)

    This study was undertaken to determine the aesthetic changes inherent in partial mastectomy followed by radiation therapy in the treatment of stage I and stage II breast cancer. A retrospective analysis of breast cancer patients treated according to the National Surgical Adjuvant Breast Project Protocol B-06 was undertaken in 57 patients from 1984 to the present. The size of mastectomy varied between 2 x 1 cm and 15 x 8 cm. Objective aesthetic outcome, as determined by physical and photographic examination, was influenced primarily by surgical technique as opposed to the effects of radiation. These technical factors included orientation of resections, breast size relative to size of resection, location of tumor, and extent and orientation of axillary dissection. Regarding cosmesis, 80 percent of patients treated in this study judged their result to be excellent or good, in comparison to 50 percent excellent or good as judged by the plastic surgeon. Only 10 percent would consider mastectomy with reconstruction for contralateral disease. Asymmetry and contour abnormalities are far more common than noted in the radiation therapy literature. Patients satisfaction with lumpectomy and radiation, however, is very high. This satisfaction is not necessarily based on objective criteria defining aesthetic parameters, but is strongly influenced by retainment of the breast as an original body part

  4. A method of estimating fetal dose during brain radiation therapy

    International Nuclear Information System (INIS)

    Purpose: To develop a simple method of estimating fetal dose during brain radiation therapy. Methods and Materials: An anthropomorphic phantom was modified to simulate pregnancy at 12 and 24 weeks of gestation. Fetal dose measurements were carried out using thermoluminescent dosimeters. Brain radiation therapy was performed with two lateral and opposed fields using 6 MV photons. Three sheets of lead, 5.1-cm-thick, were positioned over the phantom's abdomen to reduce fetal exposure. Linear and nonlinear regression analysis was used to investigate the dependence of radiation dose to an unshielded and/or shielded fetus upon field size and distance from field isocenter. Results: Formulas describing the exponential decrease of radiation dose to an unshielded and/or shielded fetus with distance from the field isocenter are presented. All fitted parameters of the above formulas can be easily derived using a set of graphs showing their correlation with field size. Conclusion: This study describes a method of estimating fetal dose during brain radiotherapy, accounting for the effects of gestational age, field size and distance from field isocenter. Accurate knowledge of absorbed dose to the fetus before treatment course allows for the selection of the proper irradiation technique in order to achieve the maximum patient benefit with the least risk to the fetus

  5. 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.

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

    International Nuclear Information System (INIS)

    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

  7. Intensity-modulated radiation therapy for oropharyngeal cancer: radiation dosage constraint at the anterior mandible.

    NARCIS (Netherlands)

    Verdonck, H.W.; Jong, J.M. de; Granzier, M.E.; Nieman, F.H.; Baat, C. de; Stoelinga, P.J.W.

    2009-01-01

    Because the survival of endosseous implants in irradiated bone is lower than in non-irradiated bone, particularly if the irradiation dose exceeds 50Gy, a study was carried out to assess the irradiation dose in the anterior mandible, when intensity modulated radiation therapy (IMRT) is used. The hypo

  8. Vocal changes in patients undergoing radiation therapy for glottic carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.; Harrison, L.B.; Solomon, B.; Sessions, R.B. (Memorial Sloan-Kettering Cancer Center, New York, NY (USA))

    1990-06-01

    A prospective evaluation of vocal changes in patients receiving radiation therapy for T1 and T2 (AJC) glottic carcinoma was undertaken in January 1987. Vocal analysis was performed prior to radiotherapy and at specific intervals throughout the radiation treatment program. The voicing ratio was extrapolated from a sustained vowel phonation using the Visipitch interfaced with the IBM-PC. Preliminary observations suggested three distinct patterns of vocal behavior: 1. reduced voicing ratio with precipitous improvement within the course of treatment, 2. high initial voicing ratio with reduction secondary to radiation induced edema, with rapid improvement in the voicing component after the edema subsided, and 3. fluctuating voicing ratio during and following treatment. Enrollment of new patients and a 2-year follow-up of current patients was undertaken.

  9. Local dose enhancement in radiation therapy: Monte Carlo simulation study

    International Nuclear Information System (INIS)

    The development of nanotechnology has boosted the use of nanoparticles in radiation therapy in order to achieve greater therapeutic ratio between tumor and healthy tissues. Gold has been shown to be most suitable to this task due to the high biocompatibility and high atomic number, which contributes to a better in vivo distribution and for the local energy deposition. As a result, this study proposes to study, nanoparticle in the tumor cell. At a range of 11 nm from the nanoparticle surface, results have shown an absorbed dose 141 times higher for the medium with the gold nanoparticle compared to the water for an incident energy spectrum with maximum photon energy of 50 keV. It was also noted that when only scattered radiation is interacting with the gold nanoparticles, the dose was 134 times higher compared to enhanced local dose that remained significant even for scattered radiation. (author)

  10. 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......: The ViewRay treatment planning system (Oakwood Village, OH) was used to create (60)Co IMRT treatment plans for 33 cancer patients with disease in the abdominal, pelvic, thorax, and head and neck regions using physician-specified patient-specific target coverage and organ at risk (OAR) objectives. Backup...... plans using a third-party linear accelerator (linac)-based planning system were also created. Plans were evaluated by attending physicians and approved for treatment. The (60)Co and linac plans were compared by evaluating conformity numbers (CN) with 100% and 95% of prescription reference doses...

  11. The new radiation protection ordinance and its consequences in radiation therapy

    International Nuclear Information System (INIS)

    The new radiation protection ordinance (StrlSchV) entails a number of additional or changed instructions. They require that personnel exposed to radiation at work be reclassified, or that personnel not exposed to radiation at work be classified as personnel exposed to radiation at work, that local dosage measurements be taken particularly in radiation therapy, in order to insure that the radiation protection areas prevailing to date can be maintained, that generally accessible areas be examined to determine whether with persons not exposed to radiation in the course of work, in the case of their prolonged presence there, 1 mSv per year is not exceeded, that instructions be put in writing, that at regular 5-year intervals the proficiency of physicians, specialists in medical physics and MTRAs be brought up to date and, that medical positions for radiooncologists be established. The stricter requirements in radiation protection are inevitably connected with greater expenditures and higher costs. These results of the new radiation protection ordinance are in direct opposition to the financial possibilities that are being restricted through budgeting and pressure on hospitals and practices to reduce costs. (orig.)

  12. 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

  13. Radiation bronchitis in lung cancer patient treated with stereotactic radiation therapy

    International Nuclear Information System (INIS)

    We report a case of chronic radiation bronchitis that developed in a patient with lung cancer treated with fractionated stereotactic radiation therapy. A 73-year-old woman with a medically inoperable T1N0M0 adenocarcinoma of the lung was treated with stereotactic radiation therapy. By using eight non-coplanar ports, 50 Gy/5 fractions was delivered in two weeks. At four weeks, a partial response was obtained with no acute adverse reaction. She developed severe cough at six months. Fiberoptic bronchoscopy revealed thick circumferentially coated bronchial mucosa in close proximity to the tumor site. At 12 months, follow-up study confirmed marked stenotic change in the B6 segmental bronchus without tumor progression. (author)

  14. 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.

  15. Adaptive response induced by occupational exposures to ionizing radiation

    International Nuclear Information System (INIS)

    We have found a significant decreased sensitivity to the cytogenetic effects of both ionizing radiation (IR) (2 Gy of γ rays) and bleomycin (BLM, 0,03 U/ml), in lymphocytes from individuals occupationally exposed to IR when compared with controls. These results suggest that occupational exposures to IR can induce adaptive response that can be detected by a subsequent treatment either by IR or by BLM. When a comparison is made between the cytogenetic effects of both treatments, no correlation was observed at the individual level. On the other hand, the individual frequencies of chromosome aberrations induced by a challenge dose of IR were negatively correlated with the occupationally received doses during the last three years. This correlation was not observed after the challenge treatment of BLM. Moreover, the individual frequencies of chromosome aberrations induced by IR treatment were homogeneous. This is not the case of the individual frequencies of chromatid aberrations induced by BLM, where a great heterogeneity was observed. (authors)

  16. 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.

  17. Acute toxicity in comprehensive head and neck radiation for nasopharynx and paranasal sinus cancers: cohort comparison of 3D conformal proton therapy and intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    To evaluate acute toxicity endpoints in a cohort of patients receiving head and neck radiation with proton therapy or intensity modulated radiation therapy (IMRT). Forty patients received comprehensive head and neck radiation including bilateral cervical nodal radiation, given with or without chemotherapy, for tumors of the nasopharynx, nasal cavity or paranasal sinuses, any T stage, N0-2. Fourteen received comprehensive treatment with proton therapy, and 26 were treated with IMRT, either comprehensively or matched to proton therapy delivered to the primary tumor site. Toxicity endpoints assessed included g-tube dependence at the completion of radiation and at 3 months after radiation, opioid pain medication requirement compared to pretreatment normalized as equivalent morphine dose (EMD) at completion of treatment, and at 1 and 3 months after radiation. In a multivariable model including confounding variables of concurrent chemotherapy and involved nodal disease, comprehensive head and neck radiation therapy using proton therapy was associated with a lower opioid pain requirement at the completion of radiation and a lower rate of gastrostomy tube dependence by the completion of radiation therapy and at 3 months after radiation compared to IMRT. Proton therapy was associated with statistically significant lower mean doses to the oral cavity, esophagus, larynx, and parotid glands. In subgroup analysis of 32 patients receiving concurrent chemotherapy, there was a statistically significant correlation with a greater opioid pain medication requirement at the completion of radiation and both increasing mean dose to the oral cavity and to the esophagus. Proton therapy was associated with significantly reduced radiation dose to assessed non-target normal tissues and a reduced rate of gastrostomy tube dependence and opioid pain medication requirements. This warrants further evaluation in larger studies, ideally with patient-reported toxicity outcomes and quality of life

  18. Melanoma Therapy via Peptide-Targeted a-Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Yubin; Hylarides, Mark; Fisher, Darrell R.; Shelton, Tiffani; Moore, Herbert A.; Wester, Dennis W.; Fritzberg, Alan R.; Winkelmann, Christopher T.; Hoffman, Timothy J.; Quinn, Thomas P.

    2005-08-01

    Malignant melanoma is the most lethal form of skin cancer. Current chemotherapy and external beam radiation therapy regimens are ineffective agents against melanoma, as shown by a 10-year survival rate for patients with disseminated disease of approximately 5% (reference?). In this study, the unique combination of a melanoma targeting peptide and an in vivo generated a-particle emitting radioisotope was investigated for its melanoma therapy potential. Alpha-radiation is densely ionizing and energy is locally absorbed, resulting in high concentrations of destructive free radicals and irreparable DNA double strand breaks. This high linear-energy-transfer overcomes radiation resistant tumor cells and oxygen-enhancement effects. The melanoma targeting peptide DOTA-Re(Arg11)CCMSH was radiolabeled with 212Pb, the parent of 212Bi, which decays via alpha and beta decay. Biodistribution and therapy studies were performed in the B16/F1 melanoma bearing C57 mouse flank tumor model. 212Pb[DOTA]-R e(Arg11)CCMSH exhibited rapid tumor uptake and extended retention coupled with rapid whole body disappearance. Radiation dose delivered to the tumor was estimated to be 61 cGy/uCi 212Pb administered. Treatment of melanoma-bearing mice with 50, 100 and 200 uCi of 212Pb[DOTA]-Re(Arg11)CCMSH extended mean survival of mice to 22, 28, and 49.8 days, respectively, compared to the 14.6 day mean survival of the placebo control group. Forty-five percent of the mice receiving 200 uCi survived the study disease-free.

  19. Radiation Therapy in Carcinoma of the Vulva A Review of Fifteen Patients

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H. S.; Oh, W. Y.; Suh, C. O.; Kim, G. E.; Park, C. K. [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1985-06-15

    This study analyzed 15 patients who underwent a course of radiation therapy for their vulva cancer in the Yonsei Univ., from Jan., 1971 to Apr., 1985. 4 patients had initial surgery for their vulva cancer and were subsequently treated by a course of adjuvant radiation therapy. 11 patients were given radiation therapy as the initial course of therapy, and one of these was in adjuvant setting before radical surgery. The most common failure site was primary site failure.

  20. Radiation Therapy in Carcinoma of the Vulva A Review of Fifteen Patients

    International Nuclear Information System (INIS)

    This study analyzed 15 patients who underwent a course of radiation therapy for their vulva cancer in the Yonsei Univ., from Jan., 1971 to Apr., 1985. 4 patients had initial surgery for their vulva cancer and were subsequently treated by a course of adjuvant radiation therapy. 11 patients were given radiation therapy as the initial course of therapy, and one of these was in adjuvant setting before radical surgery. The most common failure site was primary site failure

  1. Spontaneous pneumothorax as a complication of radiation therapy for primary lung cancer

    International Nuclear Information System (INIS)

    Spontaneous pneumothorax occured as a complication in out of 419 cases of primary lung cancer treated with radiation therapy during the last ten years. Two cases were seen during the course of radiation therapy with improvement of atelectasis and the 4 other cases were observed after completion of radiation therapy with radiation pneumonitis and fibrosis. One of the 4 cases was treated with combined chemotherapy. Continuous suction was necessary in only 2 cases. Prognosis was unchanged by this complication. (author)

  2. Spontaneous pneumothorax as a complication of radiation therapy for primary lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, M.; Nakajima, N.; Hayakawa, K.; Okazaki, A.; Maehara, Y. (Gunma Univ., Maebashi (Japan). School of Medicine)

    1980-12-01

    Spontaneous pneumothorax occured as a complication in 6 out of 419 cases of primary lung cancer treated with radiation therapy during the last ten years. Two cases were seen during the course of radiation therapy with improvement of atelectasis and the 4 other cases were observed after completion of radiation therapy with radiation pneumonitis and fibrosis. One of the 4 cases was treated with combined chemotherapy. Continuous suction was necessary in only 2 cases. Prognosis was unchanged by this complication.

  3. Managing complications of radiation therapy in head and neck cancer patients: Part I. Management of xerostomia

    OpenAIRE

    W. C. Ngeow; Chai, W. L.; Rahman, R.A.; Ramli, R

    2006-01-01

    Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they receive radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therap...

  4. 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)

  5. Non-uniform dose distributions in cranial radiation therapy

    Science.gov (United States)

    Bender, Edward T.

    Radiation treatments are often delivered to patients with brain metastases. For those patients who receive radiation to the entire brain, there is a risk of long-term neuro-cognitive side effects, which may be due to damage to the hippocampus. In clinical MRI and CT scans it can be difficult to identify the hippocampus, but once identified it can be partially spared from radiation dose. Using deformable image registration we demonstrate a semi-automatic technique for obtaining an estimated location of this structure in a clinical MRI or CT scan. Deformable image registration is a useful tool in other areas such as adaptive radiotherapy, where the radiation oncology team monitors patients during the course of treatment and adjusts the radiation treatments if necessary when the patient anatomy changes. Deformable image registration is used in this setting, but there is a considerable level of uncertainty. This work represents one of many possible approaches at investigating the nature of these uncertainties utilizing consistency metrics. We will show that metrics such as the inverse consistency error correlate with actual registration uncertainties. Specifically relating to brain metastases, this work investigates where in the brain metastases are likely to form, and how the primary cancer site is related. We will show that the cerebellum is at high risk for metastases and that non-uniform dose distributions may be advantageous when delivering prophylactic cranial irradiation for patients with small cell lung cancer in complete remission.

  6. TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists

    International Nuclear Information System (INIS)

    Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protection will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 20–40 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples of how

  7. TH-A-BRD-01: Radiation Biology for Radiation Therapy Physicists

    Energy Technology Data Exchange (ETDEWEB)

    Orton, C [Wayne State University, Grosse Pointe, MI (United States); Borras, C [Radiological Physics and Health Services, Washington, DC (United States); Carlson, D [Yale University School of Medicine, New Haven, CT (United States)

    2014-06-15

    Mechanisms by which radiation kills cells and ways cell damage can be repaired will be reviewed. The radiobiological parameters of dose, fractionation, delivery time, dose rate, and LET will be discussed. The linear-quadratic model for cell survival for high and low dose rate treatments and the effect of repopulation will be presented and discussed. The rationale for various radiotherapy techniques such as conventional fractionation, hyperfractionation, hypofractionation, and low and high dose rate brachytherapy, including permanent implants, will be presented. The radiobiological principles underlying radiation protection guidelines and the different radiation dosimetry terms used in radiation biology and in radiation protection will be reviewed. Human data on radiation induced cancer, including increases in the risk of second cancers following radiation therapy, as well as data on radiation induced tissue reactions, such as cardiovascular effects, for follow up times up to 20–40 years, published by ICRP, NCRP and BEIR Committees, will be examined. The latest risk estimates per unit dose will be presented. Their adoption in recent radiation protection standards and guidelines and their impact on patient and workers safety in radiotherapy will be discussed. Biologically-guided radiotherapy (BGRT) provides a systematic method to derive prescription doses that integrate patient-specific information about tumor and normal tissue biology. Treatment individualization based on patient-specific biology requires the identification of biological objective functions to facilitate the design and comparison of competing treatment modalities. Biological objectives provide a more direct approach to plan optimization instead of relying solely on dose-based surrogates and can incorporate factors that alter radiation response, such as DNA repair, tumor hypoxia, and relative biological effectiveness. We review concepts motivating biological objectives and provide examples of how

  8. Image-based modeling of tumor shrinkage in head and neck radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Chao Ming; Xie Yaoqin; Moros, Eduardo G.; Le, Quynh-Thu; Xing Lei [Department of Radiation Oncology, Stanford University School of Medicine, 875 Blake Wilbur Drive, Stanford, California 94305-5847 and Department of Radiation Oncology, University of Arkansas for Medical Sciences, 4301 W. Markham Street, Little Rock, Arkansas 72205-1799 (United States); Department of Radiation Oncology, Stanford University School of Medicine, 875 Blake Wilbur Drive, Stanford, California 94305-5847 (United States); Department of Radiation Oncology, University of Arkansas for Medical Sciences, 4301 W. Markham Street, Little Rock, Arkansas 72205-1799 (United States); Department of Radiation Oncology, Stanford University School of Medicine, 875 Blake Wilbur Drive, Stanford, California 94305-5847 (United States)

    2010-05-15

    Purpose: Understanding the kinetics of tumor growth/shrinkage represents a critical step in quantitative assessment of therapeutics and realization of adaptive radiation therapy. This article presents a novel framework for image-based modeling of tumor change and demonstrates its performance with synthetic images and clinical cases. Methods: Due to significant tumor tissue content changes, similarity-based models are not suitable for describing the process of tumor volume changes. Under the hypothesis that tissue features in a tumor volume or at the boundary region are partially preserved, the kinetic change was modeled in two steps: (1) Autodetection of homologous tissue features shared by two input images using the scale invariance feature transformation (SIFT) method; and (2) establishment of a voxel-to-voxel correspondence between the images for the remaining spatial points by interpolation. The correctness of the tissue feature correspondence was assured by a bidirectional association procedure, where SIFT features were mapped from template to target images and reversely. A series of digital phantom experiments and five head and neck clinical cases were used to assess the performance of the proposed technique. Results: The proposed technique can faithfully identify the known changes introduced when constructing the digital phantoms. The subsequent feature-guided thin plate spline calculation reproduced the ''ground truth'' with accuracy better than 1.5 mm. For the clinical cases, the new algorithm worked reliably for a volume change as large as 30%. Conclusions: An image-based tumor kinetic algorithm was developed to model the tumor response to radiation therapy. The technique provides a practical framework for future application in adaptive radiation therapy.

  9. Knowledge-based optimization in external radiation therapy: association of an expert-system and a numerical optimization technique in the treatment of nasopharyngeal carcinomas

    International Nuclear Information System (INIS)

    Knowledge-based optimization in external radiation therapy: association of an expert-system and a numerical optimization technique in the treatment of nasopharyngeal carcinomas. Optimization of radiation therapy in nasopharyngeal carcinoma is particularly complex due to both the proximity of at risk organs and the high dose that has to be delivered. To obtain an optimal dose distribution, a knowledge-based optimization technique has been designed that associates an expert-system, named CAVCAV, with numeric optimization (gradient projection method). Based on clinical and physical criteria, CAVCAV determines the geometric characteristics of the radiation fields (beam direction, location and shape of the shielding blocks) for the three stages of radiation therapy of nasopharyngeal carcinomas. Stage 2-treatment fields proposed by CAVCAV, though not perfectly adapted to the patient, are mathematically (beam weights, beam directions, isocenter position) and geometrically (adaptation of fields and shape of blocks by virtual simulation) optimized. (author)

  10. Light at the end of the tunnel in radiation therapy: molecular imaging in radiation research

    International Nuclear Information System (INIS)

    Accurate dose delivery to malignant tissue in radiotherapy is quite important for enhancing the treatment efficacy while minimizing morbidity of surrounding normal tissues. Advances in therapeutic strategies and diagnosis technologies along with our understanding of the biology of tumor response to radiation therapy have paved way to allow nearly 60% of current cancer patients to be treated with Radiation Therapy. The confluence of molecular imaging and nanotechnology fields are bridging physics and medicine and are quickly making strides in opening new avenues and therapeutic strategies that complement radiation therapy - with a distinct footprint in immunotherapy, adoptive cell therapy, and targeted chemotherapy. Incorporating optical imaging in radiation therapy in my laboratory, we demonstrated that molecular probes can monitor radiation-induced physiological changes at the target and off-target sites using in vivo molecular imaging approaches. Further we show endogenous bioluminescence resulting from whole body irradiation, which is distinct from the Cherenkov radiation. Mice without anesthesia were held in ventilated mouse pie cage and subjected to 5 Gy X-ray irradiation using commercially available X-RAD320 irradiator (1 Gy/min; F2 beam hardening filter 1.5 mm Al, 0.25 mm Cu, 0.75 mm Sn,). The endogenous bioluminescence from the subjects was captured using cooled CCD camera. Significant increase (up to 100 fold) in the amounts of photons released as bioluminescence was detected during 5 min capture from the mice subjected to irradiation compared to that of the control. To determine the early inflammatory response, the reactive oxygen species (ROS) activity was monitored using L-012 (8-amino-5-chloro-7-phenylpyridol (3,4-d)pyridazine-1,4(2H,3H) dione), a chemiluminescence reporter. L-012 was administered (i.p) after 15 min of irradiation. Chemiluminescence resulting from the irradiation induced ROS activity, possible through the action of the

  11. Quasi-VMAT in high-grade glioma radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Fadda, G.; Massazza, G.; Zucca, S.; Durzu, S.; Meleddu, G.; Possanzini, M.; Farace, P. [Regional Oncological Hospital, Cagliari (Italy). Dept. of Radio-Oncology

    2013-05-15

    Purpose: To compare a quasi-volumetric modulated arc therapy (qVMAT) with three-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) for the treatment of high-grade gliomas. The qVMAT technique is a fast method of radiation therapy in which multiple equispaced beams analogous to those in rotation therapy are radiated in succession. Patients and methods: This study included 12 patients with a planning target volume (PTV) that overlapped at least one organ at risk (OAR). 3D-CRT was planned using 2-3 non-coplanar beams, whereby the field-in-field technique (FIF) was used to divide each field into 1-3 subfields to shield the OAR. The qVMAT strategy was planned with 15 equispaced beams and IMRT was planned using 9 beams with a total of 80 segments. Inverse planning for qVMAT and IMRT was performed by direct machine parameter optimization (DMPO) to deliver a homogenous dose distribution of 60 Gy within the PTV and simultaneously limit the dose received by the OARs to the recommended values. Finally, the effect of introducing a maximum dose objective (max. dose < 54 Gy) for a virtual OAR in the form of a 0.5 cm ring around the PTV was investigated. Results: The qVMAT method gave rise to significantly improved PTV{sub 95%} and conformity index (CI) values in comparison to 3D-CRT (PTV{sub 95%} = 90.7 % vs. 82.0 %; CI = 0.79 vs. 0.74, respectively). A further improvement was achieved by IMRT (PTV{sub 95%} = 94.4 %, CI = 0.78). In qVMAT and IMRT, the addition of a 0.5 cm ring around the PTV produced a significant increase in CI (0.87 and 0.88, respectively), but dosage homogeneity within the PTV was considerably reduced (PTV{sub 95%} = 88.5 % and 92.3 %, respectively). The time required for qVMAT dose delivery was similar to that required using 3D-CRT. Conclusion: These findings suggest that qVMAT should be preferred to 3D-CRT for the treatment of high-grade gliomas. The qVMAT method could be applied in hospitals, for example

  12. Quasi-VMAT in high-grade glioma radiation therapy

    International Nuclear Information System (INIS)

    Purpose: To compare a quasi-volumetric modulated arc therapy (qVMAT) with three-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) for the treatment of high-grade gliomas. The qVMAT technique is a fast method of radiation therapy in which multiple equispaced beams analogous to those in rotation therapy are radiated in succession. Patients and methods: This study included 12 patients with a planning target volume (PTV) that overlapped at least one organ at risk (OAR). 3D-CRT was planned using 2-3 non-coplanar beams, whereby the field-in-field technique (FIF) was used to divide each field into 1-3 subfields to shield the OAR. The qVMAT strategy was planned with 15 equispaced beams and IMRT was planned using 9 beams with a total of 80 segments. Inverse planning for qVMAT and IMRT was performed by direct machine parameter optimization (DMPO) to deliver a homogenous dose distribution of 60 Gy within the PTV and simultaneously limit the dose received by the OARs to the recommended values. Finally, the effect of introducing a maximum dose objective (max. dose 95% and conformity index (CI) values in comparison to 3D-CRT (PTV95% = 90.7 % vs. 82.0 %; CI = 0.79 vs. 0.74, respectively). A further improvement was achieved by IMRT (PTV95% = 94.4 %, CI = 0.78). In qVMAT and IMRT, the addition of a 0.5 cm ring around the PTV produced a significant increase in CI (0.87 and 0.88, respectively), but dosage homogeneity within the PTV was considerably reduced (PTV95% = 88.5 % and 92.3 %, respectively). The time required for qVMAT dose delivery was similar to that required using 3D-CRT. Conclusion: These findings suggest that qVMAT should be preferred to 3D-CRT for the treatment of high-grade gliomas. The qVMAT method could be applied in hospitals, for example, which have limited departmental resources and are not equipped with systems capable of VMAT delivery. (orig.)

  13. 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

  14. 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.

  15. Normal tissue tolerance to external beam radiation therapy: Skin

    International Nuclear Information System (INIS)

    Acute skin toxicity is frequent during radiation therapy and can lead to temporary arrest of the treatment. Chronic toxicity can occur and conduct to cosmetic problems. Alopecia is the most frequent toxicity concerning hair and is most of the time reversible. Several factors linked to patients influence skin toxicity, such as under-nutrition, old age, obesity, smoking, skin diseases, autoimmune diseases, failure of DNA reparation. Skin, hair and nail toxicities depend also on radiation schedule. Acute toxicity is greater when dose per fraction increases. Chronic and acute toxicities are more often when total dose increases. Under 45 Gy, the risk of severe skin toxicity is low, and begins above 50 Gy. Skin toxicity depends also on the duration of radiotherapy and split course schedules are associated with less toxicities. Irradiation surface seems to influence skin toxicity but interaction is more complex. Reirradiation is often feasible in case of cancer recurrence but with a risk of grade 3-4 toxicity above all in head and neck cancer. The benefit/risk ratio has to be always precisely evaluated. Permanent alopecia is correlated with the follicle dose. Modern techniques of radiation therapy allow to spare skin. (authors)

  16. 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)

  17. 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.

  18. The value of radiation therapy for pituitary tumors

    Energy Technology Data Exchange (ETDEWEB)

    Watari, Tsutomu [Dokkyo Univ., Mibu, Tochigi (Japan). School of Medicine

    1995-09-01

    Following points are discussed in this review. (1) Historical review of our previous therapeutic management. (2) Classification of pituitary adenomas. (3) Clinical analysis of my recent 58 cases. (4) Verification of usefulness of postoperative irradiation which achieved to increase in local control rate. (5) Authoritativeness of radiotherapy. In general, 3 to 4 portal technique or arc therapy were employed. The lateral opposing field technique was avoid to use. The recommended doses using linear accelerator x-ray technique is approximately 5000 cGy in 5 weeks. To prevent radiation hazard; (1) examiner should not use technique of two opposed fields, (2) total doses should not exceed 5000 cGy in 5 to 6 weeks and the use of daily fractions should not exceed 200 cGy. (6) Correlation of hormone secreting tumors and radiation therapy. (7) Problem of radiosurgery and heavy particle. (8) Countermeasure for recurrence cases. (9) Problem of side effects of radiotherapy and its precaution. Complication of radiation for pituitary adenoma found that the significant side effects are negligibly small in recent years. (10) Pituitary tumor are originally slow growing and benign tumor, therefore the response to irradiation takes long time to elapse for final evaluation. For instance, over 80 to 90% of acromegaly patients respond HGH successfully, but this may require from one to several years. (11) Conclusion. (author).

  19. 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.

  20. Neoadjuvant chemotherapy and radiation therapy in advanced stage nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    To assess the feasibility and the toxicity of the neoadjuvant chemotherapy on the treatment of patients with locoregionally advanced nasopharyngeal carcinoma. We analyzed 77 previously untreated and histologically confirmed advanced stage nasopharyngeal carcinoma patients treated with neoadjuvant chemotherapy followed by radiation therapy at the Seoul National University Hospital between 1984 and 1996. The stage distribution was as follows: AJCC stage 111-2, stage IV-75. Sixty-six patients received infusion of 5-FU (1000 mg/m2, on Day 1-5) and cisplatin (100 mg/m2, on Day 1), eleven patients received infusion of 5.FU (1000 mg/m2, on Day 1-5) and carboplatin (300 mg/m2, on Day 1) as neoadjuvant chemotherapy prior to radiation therapy. The median follow-up for surviving patients was 44 months. The overall chemotherapy response rates were 87%. The toxicities of chemotherapy were mild. Only 3 patients experienced Grade 3 toxicities (1 for cytopenia, 2 for nausea/vomiting). The degree of radiation induced mucositis was not severe, and ten patients developed Grade 2 mucositis. The 5-year overall survival rates were 68% and the 5-year disease free survival rates were 65%. The 5-year freedom from distant metastasis rates were 82% and 5-year locoregional control rates were 75%. This single institution experience suggests that neoadjuvant chemotherapy improves overall survival and disease free survival for patients with advanced stage nasopharyngeal carcinoma without increase of toxicity

  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), 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)

  2. 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. PMID:27095755

  3. Radiation Therapy for the Management of Brain Metastases.

    Science.gov (United States)

    Garrett, Matthew D; Wu, Cheng-Chia; Yanagihara, Ted K; Jani, Ashish; Wang, Tony J C

    2016-08-01

    Brain metastases are the most common malignant intracranial tumors and carry a poor prognosis. The management of brain metastases may include a variety of treatment modalities including surgical resection, radiation therapy, and/or systemic therapy. The traditional treatment for brain metastasis involved whole brain irradiation. However, improved systemic control of primary cancers has led to longer survival for some groups of patients and there is increasing need to consider the late effects of radiation to the entire brain. With advances in imaging and radiation treatment planning and delivery stereotactic radiosurgery has become more frequently utilized and may be delivered through Gamma Knife Stereotactic Radiosurgery or linear accelerator-based systems. Furthermore, experience in treating thousands of patients on clinical trials has led to diagnosis-specific prognostic assessment systems that help guide our approach to the management of this common clinical scenario. This review provides an overview of the literature supporting radiotherapy for brain metastasis and an update on current radiotherapeutic options that is tailored for the nonradiation oncologist. PMID:27213494

  4. Evolution and accomplishments of the radiation therapy oncology group

    International Nuclear Information System (INIS)

    Purpose: The Radiation Therapy Oncology Group (RTOG) recently completed its first quarter century as a cooperative clinical cancer research organization. It is timely and appropriate to document its origins, evolution, and accomplishments. Methods and Materials: The historical review of the RTOG called upon written and oral documentation. Results: The RTOG is the most enduring product of the Committee for Radiation Therapy Studies (CRTS). Although not one of the original 17 clinical trials groups developed by the National Cancer Institute in 1956, the RTOG has pursued trials suggested by laboratory findings including the oxygen effect, intrinsic radiosensitivity, proliferation kinetics of normal and tumor cells, and interactions with other cytotoxic agents. Improvements in survival have been demonstrated for patients with carcinoma of the esophagus and cervix, and nonsmall cell carcinomas of the lung. The national and international radiation oncology communities have benefited from standards and quality control/assurance guidelines for established and new modalities. A growing number of institutions in North America participate in RTOG trials. Conclusion: The RTOG is an important clinical research resource, which has contributed to improved outcome for patients with many forms of cancer. It has become increasingly productive and widely adopted and endorsed by oncologists throughout North America

  5. Strategies for quality assurance of intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    In late 2011 The Swedish Society of Radiation Physics formed a working group to concentrate on the Quality Assurance of modern radiation therapy techniques. The given task was to identify and summarise the different QA strategies in Sweden and also the international recommendations. This was used to formulate recommendations for practical guidelines within Sweden. In this paper a brief summery of the group's work is presented. All the Swedish radiation therapy centres do a pre treatment verification measurement as QA for every new IMRT and VMAT plan. Physicists do it and they believe it to be time consuming. A general standpoint from all the centres was that new guidelines and legislation is needed to allow QA that does not require a measurement. Based on various international publications and recommendations the working group has presented two strategies, one where all new plans are checked through measurement and one where no measurement is needed. The measurement- based strategy is basically the same as the one used today with an extended machine QA part. The other presented strategy is process oriented where all the different parts of the treatment chain are checked separately. The final report can be found in Swedish on http://www.radiofysik.org

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

    International Nuclear Information System (INIS)

    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.

  7. 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

  8. Non-Hodgkin's lymphoma - the role of radiation therapy

    International Nuclear Information System (INIS)

    Objective: To review the approach to the diagnosis, assessment, treatment and continuing management of patients with Non-Hodgkin's lymphoma with the emphasis on the role of radiation therapy in this group of diseases. The entity of 'Non-Hodgkin's Lymphoma' encompasses a diverse group of disorders involving almost any part of the body. This diversity bedevils any attempt to unify the approach to this disease on a rational basis. Nevertheless, some broad principles can be applied to almost any presentation of Non-Hodgkin's lymphoma. The approach to the management of Non-Hodgkin's lymphoma is based on the histologic type, localization and extent of disease and other disease and patient related prognostic factors. The accurate pathologic diagnosis of lymphoma has been greatly facilitated by availability of markers, molecular and genetic techniques. The newly proposed revised classification of lymphomas and its impact on these of RT will be discussed. Although the Ann Arbor staging classification has been shown to provide important prognostic information, other factors have equivalent, if not greater, influence on outcome in patients with Non-Hodgkin's lymphomas. The management of lymphomas is based primarily on the histologic type and extent of the disease including stage, tumour bulk, number of sites involved and location of the disease. The success of curative radiation therapy is contingent upon the presence of localized disease, normal tissue tolerance allowing the delivery of RT curative dose (30-35 Gy) and the tumour bulk. The current evidence suggests that locoregional RT for stage I and II low grade lymphoma results in approximately 50% prolonged (10-15 years) failure free rate and possible cure. Radiation alone is no longer used for intermediate and high grade lymphomas. The standard management of stage I and II intermediate grade large cell and mixed lymphomas is with doxorubicin based chemotherapy (e.g. CHOP) followed by involved field radiation. The

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  11. Mental and growth retardation after medulloblastoma radiation therapy. MRI assessment of radiation injuries

    International Nuclear Information System (INIS)

    We report on 3 cases of a medulloblastoma and discuss the usefulness of calculating the T2 value from long-term follow-up MRIs of 1.5 T in order to analyze the cause of mental retardation. Of 13 medulloblastoma patients who were treated at our hospital from 1970 through 1984, 4 patients survived. Excluding 1 of these patients, a 2-year-old child, the remaining 3 cases are discussed. The 3 patients underwent surgery and received postoperative craniospinal irradiation and chemotherapy. The radiation dose (tumoral dose) was 40 to 85 Gy to the posterior fossa, 0 to 30.4 Gy to the spinal cord, and 25.6 to 35.2 Gy to the whole brain. The long-term effects were evaluated by calculating the T2 value and conducting a psychometric analysis from 2 to 11 years after radiation therapy. Their respective Tanaka-Vineland IQ test results were 32, 46, and 102 and their respective growth heights were -3.6 SD, -6.4 SD, and +0.18 SD. Growth hormone deficiencies were identified in all 3 patients. The decline in ability and failure to grow became more pronounced with time. The calculated T2 values showed alterations in the hippocampus, the occipital white matter, and the hypothalamus of all 3 patients. The hippocampal alteration contributed to a decline in intellectual ability and resulted in learning difficulties at school. It should be noted that in addition to whole-brain radiation that was pursued, the focal radiation provided delivers the same radiation dose to the hippocampus as to the tumor. Such a high radiation dose thus might be responsible for the decline in intellectual ability. Therefore, to avoid radiation injury to these areas, stereotactic radiosurgery must be planned for focal radiation therapy. (K.H.)

  12. Adaptive Multichannel Radiation Sensors for Plant Parameter Monitoring

    Science.gov (United States)

    Mollenhauer, Hannes; Remmler, Paul; Schuhmann, Gudrun; Lausch, Angela; Merbach, Ines; Assing, Martin; Mollenhauer, Olaf; Dietrich, Peter; Bumberger, Jan

    2016-04-01

    Nutrients such as nitrogen are playing a key role in the plant life cycle. They are much needed for chlorophyll production and other plant cell components. Therefore, the crop yield is strongly affected by plant nutrient status. Due to the spatial and temporal variability of soil characteristics or swaying agricultural inputs the plant development varies within a field. Thus, the determination of these fluctuations in the plant development is valuable for a detection of stress conditions and optimization of fertilisation due to its high environmental and economic impact. Plant parameters play crucial roles in plant growth estimation and prediction since they are used as indicators of plant performance. Especially indices derived out of remote sensing techniques provide quantitative information about agricultural crops instantaneously, and above all, non-destructively. Due to the specific absorption of certain plant pigments, a characteristic spectral signature can be seen in the visible and IR part of the electromagnetic spectrum, known as narrow-band peaks. In an analogous manner, the presence and concentration of different nutrients cause a characteristic spectral signature. To this end, an adequate remote sensing monitoring concept is needed, considering heterogeneity and dynamic of the plant population and economical aspects. This work will present the development and field investigations of an inexpensive multichannel radiation sensor to observe the incoming and reflected specific parts or rather distinct wavelengths of the solar light spectrum on the crop and facilitate the determination of different plant indices. Based on the selected sensor wavelengths, the sensing device allows the detection of specific parameters, e.g. plant vitality, chlorophyll content or nitrogen content. Besides the improvement of the sensor characteristic, the simple wavelength adaption, and the price-performance ratio, the achievement of appropriate energy efficiency as well as a

  13. Is the Adaptive Response an Efficient Protection Against the Detrimental Effects of Space Radiation

    Science.gov (United States)

    Mortazavi, S. M. Javad; Cameron, J. R.; Niroomand-rad, A.

    2003-07-01

    exposure to high-energy neutrons, protons and HZE particles during a deep space mission, needs an efficient protection against the detrimental effects of space radiation. Recent findings concerning the induction of adaptive response by neutrons and high cumulative doses of gamma radiation in human cells have opened a new horizon for possible implications of adaptive response in radiation protection and esp ecially in protection against detrimental effects of high levels of radiation during a long-term space journey. We demonstrated significant adaptive response in humans after exposure to high levels of natural radiation. Individuals whose cumulative radiation doses were up to 950 mSv, showed a significant adaptive response after exposure to 1.5 Gy gamma radiation. These doses are much lower than those received by astronauts during a sixmonth space mission. Screening the adaptive response of candidates for long-term space missions will help scientists identify individuals who not only show low radiation susceptibility but also demonstrate a high magnitude of radioadaptive response. In selected individuals, chronic exposure to elevated levels of space radiation during a long-term mission can considerably decrease their radiation susceptibility and protect them against the unpredictable exposure to relatively high radiation levels due to solar activity. Keywords: Space radiation, adaptive response, chromosome aberrations. Introduction In recent decades, humans successfully experienced relatively long time space missions. No doubt, in the near future deep space journeys as long as a few years will be inevitable. Despite current advances, there are still some great problems that limit the duration of such long-term space missions. Radiation risk due to exposure to high levels of cosmic rays and the effects of microgravity are clearly the most important problems that need to be solved before a long-term

  14. 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)

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

    International Nuclear Information System (INIS)

    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)

  16. A Method for Evaluating Quality Assurance Needs in Radiation Therapy

    International Nuclear Information System (INIS)

    The increasing complexity of modern radiation therapy planning and delivery techniques challenges traditional prescriptive quality control and quality assurance programs that ensure safety and reliability of treatment planning and delivery systems under all clinical scenarios. Until now quality management (QM) guidelines published by concerned organizations (e.g., American Association of Physicists in Medicine [AAPM], European Society for Therapeutic Radiology and Oncology [ESTRO], International Atomic Energy Agency [IAEA]) have focused on monitoring functional performance of radiotherapy equipment by measurable parameters, with tolerances set at strict but achievable values. In the modern environment, however, the number and sophistication of possible tests and measurements have increased dramatically. There is a need to prioritize QM activities in a way that will strike a balance between being reasonably achievable and optimally beneficial to patients. A systematic understanding of possible errors over the course of a radiation therapy treatment and the potential clinical impact of each is needed to direct limited resources in such a way to produce maximal benefit to the quality of patient care. Task Group 100 of the AAPM has taken a broad view of these issues and is developing a framework for designing QM activities, and hence allocating resources, based on estimates of clinical outcome, risk assessment, and failure modes. The report will provide guidelines on risk assessment approaches with emphasis on failure mode and effect analysis (FMEA) and an achievable QM program based on risk analysis. Examples of FMEA to intensity-modulated radiation therapy and high-dose-rate brachytherapy are presented. Recommendations on how to apply this new approach to individual clinics and further research and development will also be discussed

  17. 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.

  18. Conservative surgery and radiation therapy for early breast cancer

    International Nuclear Information System (INIS)

    A retrospective review of 402 patients with stage I or II invasive breast carcinoma treated with conservative surgery and radiotherapy between 1979 and 1992 w as done. Disease free and actuarial survival rates, local, regional and distant recurrence rates and treatment related acute and chronic complications were evaluated according to stage. The technique and dose of radiotherapy were assessed in relation to stage of the disease, status of margin of lumpectomy and cosmetic results. Treatment related morbidity was minimal and overall cosmetic results were excellent. In stage 0 (in situ), I and II survival at 12 years has been 100%, 90% and 80% respectively. It is concluded that breast conservation treatment is an appropriate method of primary therapy, along with radiation therapy, for women with Stage I and II breast cancer

  19. Cherenkov imaging and biochemical sensing in vivo during radiation therapy

    Science.gov (United States)

    Zhang, Rongxiao

    While Cherenkov emission was discovered more than eighty years ago, the potential applications of imaging this during radiation therapy have just recently been explored. With approximately half of all cancer patients being treated by radiation at some point during their cancer management, there is a constant challenge to ensure optimal treatment efficiency is achieved with maximal tumor to normal tissue therapeutic ratio. To achieve this, the treatment process as well as biological information affecting the treatment should ideally be effective and directly derived from the delivery of radiation to the patient. The value of Cherenkov emission imaging was examined here, primarily for visualization of treatment monitoring and then secondarily for Cherenkov-excited luminescence for tissue biochemical sensing within tissue. Through synchronized gating to the short radiation pulses of a linear accelerator (200Hz & 3 micros pulses), and applying a gated intensified camera for imaging, the Cherenkov radiation can be captured near video frame rates (30 frame per sec) with dim ambient room lighting. This procedure, sometimes termed Cherenkoscopy, is readily visualized without affecting the normal process of external beam radiation therapy. With simulation, phantoms and clinical trial data, each application of Cherenkoscopy was examined: i) for treatment monitoring, ii) for patient position monitoring and motion tracking, and iii) for superficial dose imaging. The temporal dynamics of delivered radiation fields can easily be directly imaged on the patient's surface. Image registration and edge detection of Cherenkov images were used to verify patient positioning during treatment. Inter-fraction setup accuracy and intra-fraction patient motion was detectable to better than 1 mm accuracy. Cherenkov emission in tissue opens up a new field of biochemical sensing within the tissue environment, using luminescent agents which can be activated by this light. In the first study of

  20. Surgery and radiation therapy for extramedullary plasmacytoma of the penile mucosa in a dog.

    Science.gov (United States)

    Wypij, Jackie M; de Lorimier, Louis-Philippe

    2012-09-01

    A 10-year-old neutered male Italian greyhound dog was presented because it had a penile plasmacytoma. Surgery followed by radiation therapy resulted in local control and survival for 1688 days. This is the first report of surgery and definitive radiation therapy for curative intent therapy of extramedullary penile plasmacytoma in a dog. PMID:23450865

  1. Surgery and radiation therapy for extramedullary plasmacytoma of the penile mucosa in a dog

    OpenAIRE

    Wypij, Jackie M.; de Lorimier, Louis-Philippe

    2012-01-01

    A 10-year-old neutered male Italian greyhound dog was presented because it had a penile plasmacytoma. Surgery followed by radiation therapy resulted in local control and survival for 1688 days. This is the first report of surgery and definitive radiation therapy for curative intent therapy of extramedullary penile plasmacytoma in a dog.

  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...

  3. Surgical radiation and drug therapy of breast cancer

    International Nuclear Information System (INIS)

    There main components of the program of radical therapy of breast cancer are distinguished: surgical, radiation and drug. The surgical operation continues to be one of the main therapeutic methods, though there is a trend towards limitation of the amount of surgical interventions. Investigations are carried out in the performance of rational operations of the cancer of the 1 and 2 stages supplemented with pre- and postoperative irradiation. Techniques of large dose fractionation are doveloped. It is shown that in case of 2b and 3a,b stages it is oppropriate to assign a combined or complex therapy: operation, irradiation and chemotherapy. The advantages of polychemotherapy via monochemotherapy are noted. The effect of immunotherapy on the efficiency of the therapy of brest cancer is studied. A conclusion is made that a certain progress has been reached recently in the treatment of breast cancer and that only an individual approach should be used when choosing therapy tactics taking into account all vital factors

  4. 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.

  5. Plastic scintillation dosimetry for radiation therapy: minimizing capture of Cerenkov radiation noise

    International Nuclear Information System (INIS)

    Over the last decade, there has been an increased interest in scintillation dosimetry using small water-equivalent plastic scintillators, because of their favourable characteristics when compared with other more commonly used detector systems. Although plastic scintillators have been shown to have many desirable dosimetric properties, as yet there is no successful commercial detector system of this type available for routine clinical use in radiation oncology. The main factor preventing this new technology from realizing its full potential in commercial applications is the maximization of signal coupling efficiency and the minimization of noise capture. A principal constituent of noise is Cerenkov radiation. This study reports the calculated capture of Cerenkov radiation by an optical fibre in the special case where the radiation is generated by a relativistic particle on the fibre axis and the fibre axis is parallel to the Cerenkov cone. The fraction of radiation captured is calculated as a function of the fibre core refractive index and the refractive index difference between the core and the cladding of the fibre for relativistic particles. This is then used to deduce the relative intensity captured for a range of fibre core refractive indices and fibre core-cladding refractive index differences. It is shown that the core refractive index has little effect on the amount of radiation captured compared to the refractive index difference. The implications of this result for the design of radiation therapy plastic scintillation dosimeters are considered

  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. A maximum feasible subset algorithm with application to radiation therapy

    DEFF Research Database (Denmark)

    Sadegh, Payman

    1999-01-01

    inequalities. Special classes of this problem are of interest in a variety of areas such as pattern recognition, machine learning, operations research, and medical treatment planning. This problem is generally solvable in exponential time. A heuristic polynomial time algorithm is presented in this paper. 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....

  8. 3D Monte Carlo radiation transfer modelling of photodynamic therapy

    Science.gov (United States)

    Campbell, C. Louise; Christison, Craig; Brown, C. Tom A.; Wood, Kenneth; Valentine, Ronan M.; Moseley, Harry

    2015-06-01

    The effects of ageing and skin type on Photodynamic Therapy (PDT) for different treatment methods have been theoretically investigated. A multilayered Monte Carlo Radiation Transfer model is presented where both daylight activated PDT and conventional PDT are compared. It was found that light penetrates deeper through older skin with a lighter complexion, which translates into a deeper effective treatment depth. The effect of ageing was found to be larger for darker skin types. The investigation further strengthens the usage of daylight as a potential light source for PDT where effective treatment depths of about 2 mm can be achieved.

  9. The new Wuerzburg data base for radiation therapy

    International Nuclear Information System (INIS)

    Conception, structure and realisation of a new data base for radiation therapy are present. The data base utilizes the commercial data base system ORACLE and the data base language SQL. A program package for statistical analyses including Kaplan-Meier-calculations, logrank test and Gehan/Breslow test was elaborated. The input of the data recorded on form sheets is carried out on a data base of the Tumor Centre in the first instance. From there the data are transfered to the ORACLE data base. Up to now the courses of disease of about 13 000 patients are stored. Therefore, extensive and detailed statistical analyses are practicable. (orig.)

  10. Energy and intensity modulated radiation therapy with electrons

    OpenAIRE

    Olofsson, Lennart

    2005-01-01

    In recent years intensity modulated radiation therapy with photons (xIMRT) has gained attention due to its ability to reduce the dose in the tissues close to the tumour volume. However, this technique also results in a large low dose volume. Electron IMRT (eIMRT) has the potential to reduce the integral dose to the patient due to the dose fall off in the electron depth dose curves. This dose fall off makes it possible to modulate the dose distribution in the direction of the beam by selecting...

  11. Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma

    OpenAIRE

    Ebbeskov Lauritsen, Liv; Meidahl Petersen, Peter; Daugaard, Gedske

    2012-01-01

    We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost against the tumour bed) with a conventional fractionation of 2 Gy/day, 5 days per week. RT was applied as hockey-stick portals, also called L-fields. In 2 cases, the symptoms fully resolved. Therapeutic i...

  12. Whole-brain radiation therapy for brain metastases: detrimental or beneficial?

    International Nuclear Information System (INIS)

    Stereotactic radiosurgery is frequently used, either alone or together with whole-brain radiation therapy to treat brain metastases from solid tumors. Certain experts and radiation oncology groups have proposed replacing whole-brain radiation therapy with stereotactic radiosurgery alone for the management of brain metastases. Although randomized trials have favored adding whole-brain radiation therapy to stereotactic radiosurgery for most end points, a recent meta-analysis demonstrated a survival disadvantage for patients treated with whole-brain radiation therapy and stereotactic radiosurgery compared with patients treated with stereotactic radiosurgery alone. However the apparent detrimental effect of adding whole-brain radiation therapy to stereotactic radiosurgery reported in this meta-analysis may be the result of inhomogeneous distribution of the patients with respect to tumor histologies, molecular histologic subtypes, and extracranial tumor stages between the groups rather than a real effect. Unfortunately, soon after this meta-analysis was published, even as an abstract, use of whole-brain radiation therapy in managing brain metastases has become controversial among radiation oncologists. The American Society of Radiation Oncology recently recommended, in their “Choose Wisely” campaign, against routinely adding whole-brain radiation therapy to stereotactic radiosurgery to treat brain metastases. However, this situation creates conflict for radiation oncologists who believe that there are enough high level of evidence for the effectiveness of whole-brain radiation therapy in the treatment of brain metastases

  13. Role of Local Radiation Therapy in Cancer Immunotherapy.

    Science.gov (United States)

    Demaria, Sandra; Golden, Encouse B; Formenti, Silvia C

    2015-12-01

    The recent success of cancer immunotherapy has demonstrated the power of the immune system to clear tumors, generating renewed enthusiasm for identifying ways to induce antitumor immune responses in patients. Natural antitumor immune responses are detectable in a fraction of patients across multiple malignant neoplasms and can be reactivated by targeting rate-limiting immunosuppressive mechanisms. In most patients, however, interventions to induce a de novo antitumor immune response are necessary. We review growing evidence that radiation therapy targeted to the tumor can convert it into an in situ tumor vaccine by inducing release of antigens during cancer cell death in association with proinflammatory signals that trigger the innate immune system to activate tumor-specific T cells. In addition, radiation's effects on the tumor microenvironment enhance infiltration of activated T cells and can overcome some of the barriers to tumor rejection. Thus, the complementary effects of radiation on priming and effector phases of antitumor immunity make it an appealing strategy to generate immunity against a patient's own individual tumor, that through immunological memory, can result in long-lasting systemic responses. Several anecdotal cases have demonstrated the efficacy of combining radiation with available immunotherapies, and results of prospective trials are forthcoming.

  14. Fast Monte Carlo for radiation therapy: the PEREGRINE Project

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann Siantar, C.L.; Bergstrom, P.M.; Chandler, W.P.; Cox, L.J.; Daly, T.P.; Garrett, D.; House, R.K.; Moses, E.I.; Powell, C.L.; Patterson, R.W.; Schach von Wittenau, A.E.

    1997-11-11

    The purpose of the PEREGRINE program is to bring high-speed, high- accuracy, high-resolution Monte Carlo dose calculations to the desktop in the radiation therapy clinic. PEREGRINE is a three- dimensional Monte Carlo dose calculation system designed specifically for radiation therapy planning. It provides dose distributions from external beams of photons, electrons, neutrons, and protons as well as from brachytherapy sources. Each external radiation source particle passes through collimator jaws and beam modifiers such as blocks, compensators, and wedges that are used to customize the treatment to maximize the dose to the tumor. Absorbed dose is tallied in the patient or phantom as Monte Carlo simulation particles are followed through a Cartesian transport mesh that has been manually specified or determined from a CT scan of the patient. This paper describes PEREGRINE capabilities, results of benchmark comparisons, calculation times and performance, and the significance of Monte Carlo calculations for photon teletherapy. PEREGRINE results show excellent agreement with a comprehensive set of measurements for a wide variety of clinical photon beam geometries, on both homogeneous and heterogeneous test samples or phantoms. PEREGRINE is capable of calculating >350 million histories per hour for a standard clinical treatment plan. This results in a dose distribution with voxel standard deviations of <2% of the maximum dose on 4 million voxels with 1 mm resolution in the CT-slice plane in under 20 minutes. Calculation times include tracking particles through all patient specific beam delivery components as well as the patient. Most importantly, comparison of Monte Carlo dose calculations with currently-used algorithms reveal significantly different dose distributions for a wide variety of treatment sites, due to the complex 3-D effects of missing tissue, tissue heterogeneities, and accurate modeling of the radiation source.

  15. 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.

  16. 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.

  17. Treatment of retinoblastoma by precision megavoltage radiation therapy

    International Nuclear Information System (INIS)

    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. (Auth.)

  18. The design and implementation of the radiation therapy information management system (RTIMS) based on the workflow of radiation therapy

    International Nuclear Information System (INIS)

    Objective: To meet the special needs of the department of radiation oncology, a radiation therapy information management system (RTIMS) has been developed as a secondary database system to supplement the Varian Varis/Aria since 2007. Methods: The RTIMS server was used to run a database and web service of Apache + PHP + MySQL. The RTIMS sever's web service could be visited with Internet Explorer (IE) to input, search, count, and print information from about 30 workstations and 20 personal computers. As some workstations were installed with Windows and IE in English only, some functions had English version. Results: In past five years, as the RTIMS was implemented in the department, some further needs were met and more practical functions were developed. And now the RTIMS almost covered the whole workflow of radiation therapy (RT). By September 2011 , recorded patients data in the RTIMS is as follows: 3900 patients, 2600 outpatient RT records, 6800 progress notes, 1900 RT summaries, 6700 charge records, 83000 workload records, 3900 plan application forms, 1600 ICRT records. etc. Conclusions: The RTIMS based on the workflow of RT has been successfully developed and clinically implemented. And it was demonstrated to be user-friendly and was proven to significantly improve the efficiency of the department. Since it is an in-house developed system, more functions can be added or modified to further enhance its potentials in research and clinical practice. (authors)

  19. Treatment results of Intensity Modulated Radiation Therapy and Image Guided Radiation Therapy for head and neck cancers

    International Nuclear Information System (INIS)

    Purpose is to evaluate treatment results of Intensity Modulated Radiation Therapy (IMRT) and Image Guided Radiation Therapy (IGRT) for head and neck cancers. Methods and Materials: descriptive cross sectional study on 45 head and neck cancer patients treated by IMRT-IGRT with curative intent at Department of Radiation Oncology, 108 Central Military Hospital from 12/2013 to 3/2015. Results: 100% IMRT plan underwent quality assurance with gamma index ≥ 95%. Mean conformity index of IMRT plans was 1.21 ± 0.13. Patient setup errors in supero-inferior (SI), antero-posterior (AP) and medio-lateral (ML) were ≤ 3 mm. Overall treatment complete response, partial response and stable disease rates were 75.6% and 15.6 % and 8.8%, respectively. There were 42.2 % patients with no xerostomia; 57.8% grade 1 and no grade 2 - 4 xerostomia. Conclusions: Head and neck cancers treatment with IMRT-IGRT showed good tumor response with safety, high accuracy and acceptable side effects. (author)

  20. Clinical trial experience using erythropoietin during radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lavey, R.S. [Radiation Oncology Program, Childrens Hospital Los Angeles, Univ. of Southern California, CA, Los Angeles (United States)

    1998-12-01

    Oncologists have several reasons for trying to maintain or increase hemoglobin levels in their patients during therapy. Relief of the symptoms of anemia, including fatigue and dyspnea, are traditional, well-accepted indications. A newer rationale is to enhance the efficacy of radiation therapy and/or chemotherapy in controlling tumors. A laboratory animal study found that administration of recombinant human erythropoietin (rHuEPO) increased intratumoral median oxygen levels and diminished the proportion of measurements in the very low (<3 mm Hg) range. Hemoglobin level is a strong independent prognostic factor for tumor control by radiation therapy. The hemoglobin level at the end of radiation therapy is a stronger prognostic factor than is the hemoglobin level at the start of therapy. Numerous clinical trials have utilized rHuEPO during radiation with or without concurrent chemotherapy. All 4 trials which enrolled patients with low hemoglobin levels (<12 to 13.5 g/dl) found that rHuEPO significantly increased hemoglobin within 2 weeks and that hemoglobin levels continued to rise until the end of rHuEPO treatment. rHuEPO was efficacious in limiting the decrease in hemoglobin and use of packed red blood cell transfusion in the one reported trial in which it was used in patients with initially normal hemoglobin levels during intensive concurrent radiation and chemotherapy. One trial found a statistically significant improvement in complete pathologic response rate after neoadjuvant chemoradiotherapy with the use of rHuEPO. rHuEPO has a potentially large role to play in the care of the cancer patient. (orig.) [Deutsch] In der Onkologie bestehen zahlreiche Gruende, die Haemoglobinkonzentration der Patienten waehrend der Therapie zu halten oder sogar anzuheben. Als anerkannte Indikation gilt hierbei die Besserung anaemiebedingter Symptome wie Muedigkeit und Dyspnoe, wobei jedoch neuere Ergebnisse darauf hinweisen, dass auch die Effizienz der Strahlen- und

  1. Potency preservation following stereotactic body radiation therapy for prostate cancer

    International Nuclear Information System (INIS)

    Erectile dysfunction after prostate radiation therapy remains an ongoing challenge and critical quality of life issue. Given the higher dose of radiation per fraction using stereotactic body radiation therapy (SBRT) there is concern that post-SBRT impotency would be higher than conventional radiation therapy approaches. This study sought to evaluate potency preservation and sexual function following SBRT for prostate cancer. Between February 2008 and March 2011, 216 men with clinically localized prostate cancer were treated definitively with SBRT monotherapy at Georgetown University Hospital. Potency was defined as the ability to have an erection firm enough for intercourse with or without sexual aids while sexual activity was defined as the ability to have an erection firm enough for masturbation and foreplay. Patients who received androgen deprivation therapy (ADT) were excluded from this study. Ninety-seven hormone-naïve men were identified as being potent at the initiation of therapy and were included in this review. All patients were treated to 35–36.25 Gy in 5 fractions delivered with the CyberKnife Radiosurgical System (Accuray). Prostate specific antigen (PSA) and total testosterone levels were obtained pre-treatment, every 3 months for the first year and every 6 months for the subsequent year. Sexual function was assessed with the Sexual Health Inventory for Men (SHIM), the Expanded Prostate Index Composite (EPIC)-26 and Utilization of Sexual Medication/Device questionnaires at baseline and all follow-up visits. Ninety-seven men (43 low-, 50 intermediate- and 4 high-risk) at a median age of 68 years (range, 48–82 years) received SBRT. The median pre-treatment PSA was 5.9 ng/ml and the minimum follow-up was 24 months. The median pre-treatment total serum testosterone level was 11.4 nmol/L (range, 4.4-27.9 nmol/L). The median baseline SHIM was 22 and 36% of patients utilized sexual aids prior to treatment. Although potency rates declined following

  2. 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

  3. Approach of combined cancer gene therapy and radiation: response of promoters to ionizing radiation

    International Nuclear Information System (INIS)

    Gene therapy is an emerging cancer treatment modality. We are interested in developing a radiation-inducible gene therapy system to sensitize the tumor vasculature to the effects of ionizing radiation (IR) treatment. An expression system based on irradiation-inducible promoters will drive the expression of anti-tumor genes in the tumor vasculature. Solid tumors are dependent on angio genesis, a process in which new blood vessels are formed from the pre-existing vasculature. Vascular endothelial cells are un transformed and genetically stable, thus avoiding the problem of resistance to the treatments. Vascular endothelial cells may therefore represent a suitable target for this therapeutic gene therapy strategy.The identification of IR-inducible promoters native to endothelial cells was performed by gene expression profiling using cDNA micro array technology. We describe the genes modified by clinically relevant doses of IR. The extension to high doses aimed at studying the effects of total radiation delivery to the tumor. The radio-inductiveness of the genes selected for promoter study was confirmed by RT-PCR. Analysis of the activity of promoters in response to IR was also assessed in a reporter plasmid. We found that authentic promoters cloned onto a plasmid are not suitable for cancer gene therapy due to their low induction after IR. In contrast, synthetic promoters containing repeated sequence-specific binding sites for IR-activated transcription factors such as NF-κB are potential candidates for gene therapy. The activity of five tandemly repeated TGGGGACTTTCCGC elements for NF-κB binding in a luciferase reporter was increased in a dose-dependent manner. Interestingly, the response to fractionated low doses was improved in comparison to the total single dose. Thus, we put present evidence that a synthetic promoter for NF-κB specific binding may have application in the radio-therapeutic treatment of cancer. (author)

  4. Play Therapy for Bereaved Children: Adapting Strategies to Community, School, and Home Settings

    Science.gov (United States)

    Webb, Nancy Boyd

    2011-01-01

    Play therapy is a highly adaptable treatment method that can be modified according to children's ages, circumstances, and settings in which counseling occurs. Play therapy may be used in schools, community settings, and homes to help children following the death of a significant other. After reviewing basic developmental factors that affect…

  5. Vertebral fracture complications following radiation therapy. Report of two cases

    International Nuclear Information System (INIS)

    We observed the outbreak time of a spinal compression fracture following radiation therapy and its natural course. Case 1 was a 88-year-old, woman. NTX 66.9. Underwent cobalt irradiation 54 Gy for esophageal cancer. Three months after irradiation, the first lumbar vertebra was found to de compressed, and low back pain occurred. Vacuum cleft phenomenon in X-P appeared after two weeks, but anterior callus formation appeared in eight weeks, after which the low back pain disappeared. Case 2 was a 77-year-old woman. NTX 86.5. Underwent irradiation 69 Gy for uterine carcinoma. Six months after the irradiation, the fourth/five lumbar vertebra were found to be compressed. Great collapse occurred in X-P after two weeks, but stabilized and did not aggravate thereafter. Low back pain also disappeared. Radiotherapy affects bone cells (osteoblasts, osteoclasts), inhibiting bone remodeling. As a result, deficient elastic resistance occurs. Vertebral bodies are also compressed in such a situation. After that normal callus formation starts from adjacent normal bone cells. The compression fracture observed ranged from three to six months after radiation. Natural course is well. Therefore conservative therapy is recommended. (author)

  6. Intraluminal radiation therapy in the management of malignant biliary obstruction

    International Nuclear Information System (INIS)

    Fifteen patients with malignant biliary obstruction from carcinoma of the bile ducts, gallbladder, and pancreas (Group I) or metastatic disease (Group II) were treated with intraluminal radiation therapy (ILRT) at Memorial Sloan-Kettering Cancer Center. In 11 cases ILRT was used as a central boost in combination with 3000 cGy external beam radiation therapy (ERT). No significant treatment toxicity was observed. Cholangiographic response was observed in 2 of 12 evaluable patients. In no patient was long-term relief of jaundice without indwelling biliary stent achieved. Survival from treatment in eight Group I patients treated with ILRT +/- ERT was 3 to 13 months (median, 4.5). Survival in seven similarly treated Group II patients was 0.5 to 8 months (median, 4.0). Additional data for ten similar patients referred for ILRT but treated with ERT alone are presented. Analysis of this and other reports indicate the need for prospective controlled trials of the role of this regimen in the management of malignant biliary obstruction before wider application can be recommended

  7. Results of radiation therapy for carcinoma of the uterine cervix

    International Nuclear Information System (INIS)

    Fifty-nine consecutive patients who were treated with radiation therapy for carcinoma of the uterine cervix between April 1982 and December 1986 were reviewed. Twelve patients were treated with low dose-rate intracavitary irradiation using radium-226, and 46 were treated with high dose-rate irradiation using a remote afterloading system combined with external irradiation, and the other one was treated with external irradiation alone. The 5-year-survival rates for stage Ib, IIa, IIb, IIIb, and IVa were 77.8, 85.7, 87.5, 45.5 and 40.0%, respectively. The 5-year-survival rates for the low and high dose-rates irradiation were 66.7 and 73.9%, respectively. The most common complication of radiation therapy was rectal bleeding, which required conservative treatment (grade 2) in 11 (18.6%). The morbidities for the low and high dose-rates irradiation were similar. The causes of death in 17 patients were local recurrence in 14, metastases in 2 and other specified in one. These findings suggest that high dose-rate intracavitary irradiation is as effective as low dose-rate irradiation for carcinoma of the uterine cervix, and that further efforts for controlling the local tumors with stage IIIb disease without an increased rate of side-effects is required. (author)

  8. Adjuvant radiation therapy in metastatic lymph nodes from melanoma

    International Nuclear Information System (INIS)

    To analyze the outcome after adjuvant radiation therapy with standard fractionation regimen in metastatic lymph nodes (LN) from cutaneous melanoma. 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. 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 <50 Gy (80% vs. 35% at 5-year follow-up; p = 0.004). Adjuvant radiotherapy was able to increase regional control in targeted sub-population (LN with extracapsular extension)

  9. Preclinical imaging in animal models of radiation therapy

    International Nuclear Information System (INIS)

    Modern radiotherapy benefits from precise and targeted diagnostic and pretherapeutic imaging. Standard imaging modalities, such as computed tomography (CT) offer high morphological detail but only limited functional information on tumors. Novel functional and molecular imaging modalities provide biological information about tumors in addition to detailed morphological information. Perfusion magnetic resonance imaging (MRI) CT or ultrasound-based perfusion imaging as well as hybrid modalities, such as positron emission tomography (PET) CT or MRI-PET have the potential to identify and precisely delineate viable and/or perfused tumor areas, enabling optimization of targeted radiotherapy. Functional information on tissue microcirculation and/or glucose metabolism allow a more precise definition and treatment of tumors while reducing the radiation dose and sparing the surrounding healthy tissue. In the development of new imaging methods for planning individualized radiotherapy, preclinical imaging and research plays a pivotal role, as the value of multimodality imaging can only be assessed, tested and adequately developed in a preclinical setting, i.e. in animal tumor models. New functional imaging modalities will play an increasing role for the surveillance of early treatment response during radiation therapy and in the assessment of the potential value of new combination therapies (e.g. combining anti-angiogenic drugs with radiotherapy). (orig.)

  10. Selecting photoplethysmogram indicators to monitor adaptation status of a person at magnetic-laser therapy

    OpenAIRE

    Тимчик, Григорій Семенович; Осадчий, Олександр Васильович; Філіпова, Марина В’ячеславівна; Пономаренко, Альона Сергіївна; Стецька, Анна Василівна

    2014-01-01

    Magnetic-laser therapy is widely used by doctors for treating many diseases, but there is no single method of evaluating the effectiveness of selected parameters of therapy. A literature review on the presence of similar studies was conducted in the paper, and it was found that photoplethysmographic signal was widely considered, but it had no connection to magnetic-laser therapy. The purpose of this research was to argue the use of photoplethysmography to monitor the adaptation state of the h...

  11. Mesenchymal stem cell therapy for acute radiation syndrome:Innovative medical approaches in military medicine

    Institute of Scientific and Technical Information of China (English)

    Erik B.Eaton Jr.; Timothy R.Varney

    2014-01-01

    After a radiological or nuclear event, acute radiation syndrome (ARS) will present complex medical challenges that could involve the treatment of hundreds to thousands of patients. Current medical doctrine is based on limited clinical data and remains inadequate. Efforts to develop medical innovations that address ARS complications are unlikely to be generated by the industry because of market uncertainties specific to this type of injury. A prospective strategy could be the integration of cellular therapy to meet the medical demands of ARS. The most clinically advanced cellular therapy to date is the administration of mesenchymal stem cells (MSCs). Results of currently published investigations describing MSC safety and efficacy in a variety of injury and disease models demonstrate the unique qualities of this reparative cell population in adapting to the specific requirements of the damaged tissue in which the cells integrate. This report puts forward a rationale for the further evaluation of MSC therapy to address the current unmet medical needs of ARS. We propose that the exploration of this novel therapy for the treatment of the multivariate complications of ARS could be of invaluable benefit to military medicine.

  12. Stage IA non-Hodgkin's lymphoma of the Waldeyer's ring; Limited chemotherapy and radiation therapy versus radiation therapy alone

    Energy Technology Data Exchange (ETDEWEB)

    Uematsu, Minoru (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology Dept. of Radiology, National Defense Medical College, Saitama (Japan)); Kondo, Makoto (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Hiramatsu, Hideko (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Ikeda, Yasuo (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Hematology); Mikata, Sumio (Chiba Univ. (Japan). School of Medicine); Katayama, Michiaki (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Ito, Hisao (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology); Kusano, Shoichi (Dept. of Radiology, National Defense Medical College, Saitama (Japan)); Kubo, Asuchishi (Keio Univ. School of Medicine, Tokyo (Japan). Dept. of Radiology)

    1993-01-01

    Seventeen patients with stage IA non-Hodgkin's lymphoma of the Waldeyer's ring were treated with radiation therapy with or without chemotherapy. All lesions were judged as having intermediate grade malignancy in the Working Formulation. Eight patients received combined treatment with three cycles of cylcophosphamide, doxorubicin, vincristine and prednison (CHOP) and radiation therapy with 30 to 40 Gy. Another 9 patients were treated with radiation therapy 40 to 60 Gy alone. After a median follow-up of 69 months, all 8 patients, treated with combined modality were alive and relapse-free whereas 4 of the 9 treated with irradiation alone had relapsed. All relapses occurred transdiaphragmatically. Two of the 4 relapsing patients were saved, but the other two died of the disease. The 5-year relapse-free and cause-specific survival rates were 100% and 100% in the combined modality group, and 56% and 76% in the radiation therapy alone group (relapse-free: p=0.04, cause-specific: p=0.16). There were no serious complications related to treatment, although most patients complained of mouth dryness and most patients given CHOP had paresthesia. Our opinion was that the total impact of these two side-effects on quality of life was less pronounced after combined modality than after radiation therapy alone. Limited chemotherapy and radiation therapy seemed to be more beneficial than radiation therapy alone not only in relapse-free survival but also in quality of life after treatment. (orig.).

  13. Radiation-Induced Leukemia at Doses Relevant to Radiation Therapy: Modeling Mechanisms and Estimating Risks

    Science.gov (United States)

    Shuryak, Igor; Sachs, Rainer K.; Hlatky, Lynn; Mark P. Little; Hahnfeldt, Philip; Brenner, David J.

    2006-01-01

    Because many cancer patients are diagnosed earlier and live longer than in the past, second cancers induced by radiation therapy have become a clinically significant issue. An earlier biologically based model that was designed to estimate risks of high-dose radiation induced solid cancers included initiation of stem cells to a premalignant state, inactivation of stem cells at high radiation doses, and proliferation of stem cells during cellular repopulation after inactivation. This earlier model predicted the risks of solid tumors induced by radiation therapy but overestimated the corresponding leukemia risks. Methods: To extend the model to radiation-induced leukemias, we analyzed in addition to cellular initiation, inactivation, and proliferation a repopulation mechanism specific to the hematopoietic system: long-range migration through the blood stream of hematopoietic stem cells (HSCs) from distant locations. Parameters for the model were derived from HSC biologic data in the literature and from leukemia risks among atomic bomb survivors v^ ho were subjected to much lower radiation doses. Results: Proliferating HSCs that migrate from sites distant from the high-dose region include few preleukemic HSCs, thus decreasing the high-dose leukemia risk. The extended model for leukemia provides risk estimates that are consistent with epidemiologic data for leukemia risk associated with radiation therapy over a wide dose range. For example, when applied to an earlier case-control study of 110000 women undergoing radiotherapy for uterine cancer, the model predicted an excess relative risk (ERR) of 1.9 for leukemia among women who received a large inhomogeneous fractionated external beam dose to the bone marrow (mean = 14.9 Gy), consistent with the measured ERR (2.0, 95% confidence interval [CI] = 0.2 to 6.4; from 3.6 cases expected and 11 cases observed). As a corresponding example for brachytherapy, the predicted ERR of 0.80 among women who received an inhomogeneous low

  14. A Systematic Overview of Radiation Therapy Effects in Hodgkin's Lymphoma

    International Nuclear Information System (INIS)

    A systematic review of radiation therapy trials in several tumour types was carried out by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately. This synthesis of the literature on radiation therapy for Hodgkin's lymphoma (HL) is based on data from 12 randomized trials and 2 meta-analyses. Data from 3 prospective studies, 29 retrospective studies and 58 other articles were also used. In total, 58 scientific articles are included, involving 27,280 patients. The results were compared with those of a similar overview from 1996 including 38,362 patients. The conclusions reached can be summarized thus: Solid scientific documentation shows that in patients with HL more than 80% in the early stages and 60-70% of younger patients in advanced stages of disease are now cured by the development of radiotherapy and combination chemotherapy. Long-term follow-up shows that after 15 to 20 years the mortality from HL in early and intermediate stages is exceeded by other causes of death, mostly secondary malignancies and cardiac deaths, especially myocardial infarction. Convincing data show that radiotherapy plays a major role in the development of solid cancers and cardiovascular disease, but no randomized trials have been performed. During the past decade increasing awareness of fatal long-term sequelae has fundamentally changed treatment strategies in early and intermediate stages. A thorough long-term follow-up is essential to evaluate the effects of the modifications of the therapy. In early stages of disease extended field irradiation is now replaced by short periods of chemotherapy followed by limited radiotherapy to decrease late sequelae. This approach is strongly supported by early reports from randomized trials. Final results cannot be fully evaluated for many years. The optimal radiation dose and volume after chemotherapy are not defined or if irradiation is needed at all

  15. 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.

  16. 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.

  17. 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....

  18. Focused radiation hepatitis after Bragg-peak proton therapy for hepatocellular carcinoma: CT findings

    International Nuclear Information System (INIS)

    Radiation hepatitis is clearly demonstrated by noncontrast and contrast enhanced CT following radiotherapy for liver diseases. Radiation hepatitis is dependent on dose distribution and is usually demonstrated as nonsegmental bandlike lesion after photon therapy. We report a case of focused, oval-shaped radiation hepatitis that was induced by photon therapy. The attenuation difference was localized in a high-dose area caused by Bragg-peak proton therapy. 17 refs., 2 figs

  19. Skeletal sequelae of radiation therapy for malignant childhood tumors

    Energy Technology Data Exchange (ETDEWEB)

    Butler, M.S.; Robertson, W.W. Jr.; Rate, W.; D' Angio, G.J.; Drummond, D.S. (UMDNJ Robert Wood Johnson Medical School, New Brunswick (USA))

    1990-02-01

    One hundred forty-three patients who received radiation therapy for childhood tumors, and survived to the age of skeletal maturity, were studied by retrospective review of oncology records and roentgenograms. Diagnoses for the patients were the following: Hodgkin's lymphoma (44), Wilms's tumor (30), acute lymphocytic leukemia (26), non-Hodgkin's lymphoma (18), Ewing's sarcoma (nine), rhabdomyosarcoma (six), neuroblastoma (six), and others (four). Age at the follow-up examination averaged 18 years (range, 14-28 years). Average length of follow-up study was 9.9 years (range, two to 18 years). Asymmetry of the chest and ribs was seen in 51 (36%) of these children. Fifty (35%) had scoliosis; 14 had kyphosis. In two children, the scoliosis was treated with a brace, while one developed significant kyphosing scoliosis after laminectomy and had spinal fusion. Twenty-three (16%) patients complained of significant pain at the radiation sites. Twelve of the patients developed leg-length inequality; eight of those were symptomatic. Three patients developed second primary tumors. Currently, the incidence of significant skeletal sequelae is lower and the manifestations are less severe than reported in the years from 1940 to 1970. The reduction in skeletal complications may be attributed to shielding of growth centers, symmetric field selection, decreased total radiation doses, and sequence changes in chemotherapy.

  20. 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

    2015-11-10

    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.

  1. 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.

  2. Radiation therapy of hyperplastic heterotopic ossifications in osteogenesis imperfecta

    International Nuclear Information System (INIS)

    Purpose: Osteogenesis imperfecta is a rare hereditary disease of connective tissue with a genetic defect in collagen synthesis. In osteogenesis imperfecta hyperplastic heterotopic ossification can be induced by hyperplastic callus formation caused by trauma or operation. Heterotopic ossifications can be found in numerous benign diseases. The successful use of low dose radiotherapy in the treatment of heterotopic ossifications in well-known from the literature. Patients and Methods: We treated two children (a 13-year old girl and a ten-year old boy) with heterotopic ossifications of the lower extremities in osteogenesis imperfecta type IV (Lobstein) with a low dose irradiation (10x1 Gy, respectively 6x1 Gy) under megavoltage conditions. Results: After radiotherapy the children were painfree and the hyperplastic callus was considerably reduced. The previously immobilized patients could partly be mobilized. Thereby it could be contributed to the rehabilitation of the patients. New hyperplastic callus formation was not observed in the irradiated areas so far. Conclusion: Analogous to the successful radiation of heterotopic ossifications in other benign diseases radiation therapy seems to be a successful treatment of hyperplastic callus formation in osteogenesis imperfecta. Despite the late risks of radiotherapy radiation treatment of benign diseases in children might be indicated. (orig.)

  3. Skeletal sequelae of radiation therapy for malignant childhood tumors

    International Nuclear Information System (INIS)

    One hundred forty-three patients who received radiation therapy for childhood tumors, and survived to the age of skeletal maturity, were studied by retrospective review of oncology records and roentgenograms. Diagnoses for the patients were the following: Hodgkin's lymphoma (44), Wilms's tumor (30), acute lymphocytic leukemia (26), non-Hodgkin's lymphoma (18), Ewing's sarcoma (nine), rhabdomyosarcoma (six), neuroblastoma (six), and others (four). Age at the follow-up examination averaged 18 years (range, 14-28 years). Average length of follow-up study was 9.9 years (range, two to 18 years). Asymmetry of the chest and ribs was seen in 51 (36%) of these children. Fifty (35%) had scoliosis; 14 had kyphosis. In two children, the scoliosis was treated with a brace, while one developed significant kyphosing scoliosis after laminectomy and had spinal fusion. Twenty-three (16%) patients complained of significant pain at the radiation sites. Twelve of the patients developed leg-length inequality; eight of those were symptomatic. Three patients developed second primary tumors. Currently, the incidence of significant skeletal sequelae is lower and the manifestations are less severe than reported in the years from 1940 to 1970. The reduction in skeletal complications may be attributed to shielding of growth centers, symmetric field selection, decreased total radiation doses, and sequence changes in chemotherapy

  4. 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....

  5. Estimation of impairment of gustation and salivary secretion after radiation therapy for head and neck malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Yoshiyuki; Fuwa, Nobukazu; Kikuchi, Yuzo [Aichi Cancer Center, Nagoya (Japan). Hospital; Morita, Kozo; Murao, Takayuki; Yokoi, Motoo

    1995-06-01

    To estimate impairment of gustation and salivary secretion after radiation therapy, we classified the degree of gustation and xerostomia into 4 grades in 50 patients who had received radiation therapy for head and neck malignancies. We found that gustation recovered in most patients regardless of radiation dose, but salivary secretion recovered only when radiation dose was less than 40 to 50 Gy on the gland of the affected side and less than 30 to 40 Gy on the opposite side. (author).

  6. Radiation therapy of lung carcinoma; Strahlentherapie des Bronchialkarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Oertel, S.; Debus, J.; Hof, H.; Bischof, M. [Universitaetsklinikum Heidelberg, Abteilung Radioonkologie und Strahlentherapie, Heidelberg (Germany)

    2010-08-15

    At first presentation and primary diagnosis approximately 50% of patients with non-small cell lung carcinoma (NSCLC) and 25% of patients with small cell lung carcinoma (SCLC) have a potentially curable tumor stage. Definitive, adjuvant and neoadjuvant radio- (chemo-)therapy play an important role as part of multimodal treatment approaches. High radiation doses can be achieved in tumor areas with modern radiotherapy planning and treatment techniques without an increase of side-effects. The 3 year overall survival after primary radiotherapy is approximately 50% for patients with NSCLC in stage I and 20% in stage IIIA. Radiotherapy can be used in patients with progressive metastatic disease after insufficient response to systemic therapy with threatening thoracic symptoms and for palliative treatment of cerebral, lymphatic and osseous metastases. (orig.) [German] Etwa 50% der Patienten mit einem nichtkleinzelligen Bronchialkarzinom (NSCLC, ''non-small cell lung carcinoma'') und 25% der Patienten mit einem kleinzelligen Bronchialkarzinom (SCLC, ''small cell lung carcinoma'') befinden sich zum Zeitpunkt der Primaerdiagnose in einem potenziell heilbaren Tumorstadium. Die definitive, adjuvante und neoadjuvante Radio- (chemo-)therapie hat im Rahmen der multimodalen Behandlungskonzepte einen festen Stellenwert. Durch den Einsatz modernster Techniken bei der Bestrahlungsplanung und -therapie koennen hohe Strahlendosen bei gleichzeitiger Schonung des gesunden Gewebes appliziert werden. Die 3-Jahres-Ueberlebensraten fuer Patienten mit NSCLC betragen nach primaerer Bestrahlung {approx}50% im Stadium I und {approx}20% im Stadium IIIA. Im metastasierten Stadium wird eine Radiotherapie bei unzureichendem Ansprechen der systemischen Behandlung mit drohender thorakaler Symptomatik sowie zur palliativen Behandlung zerebraler, lymphogener oder ossaerer Metastasen eingesetzt. (orig.)

  7. Assessment of secondary radiation and radiation protection in laser-driven proton therapy

    Energy Technology Data Exchange (ETDEWEB)

    Faby, Sebastian; Wilkens, Jan J. [Technische Univ. Muenchen Klinikum rechts der Isar (Germany). Dept. of Radiation Oncology; Technische Univ. Muenchen (Germany). Physik-Dept.

    2015-09-01

    This work is a feasibility study of a radiation treatment unit with laser-driven protons based on a state-of-the-art energy selection system employing four dipole magnets in a compact shielded beamline. The secondary radiation emitted from the beamline and its energy selection system and the resulting effective dose to the patient are assessed. Further, it is evaluated whether or not such a compact system could be operated in a conventional treatment vault for clinical linear accelerators under the constraint of not exceeding the effective dose limit of 1 mSv per year to the general public outside the treatment room. The Monte Carlo code Geant4 is employed to simulate the secondary radiation generated while irradiating a hypothetical tumor. The secondary radiation inevitably generated inside the patient is taken into account as well, serving as a lower limit. The results show that the secondary radiation emanating from the shielded compact therapy system would pose a serious secondary dose contamination to the patient. This is due to the broad energy spectrum and in particular the angular distribution of the laser-driven protons, which make the investigated beamline together with the employed energy selection system quite inefficient. The secondary radiation also cannot be sufficiently absorbed in a conventional linear accelerator treatment vault to enable a clinical operation. A promising result, however, is the fact that the secondary radiation generated in the patient alone could be very well shielded by a regular treatment vault, allowing the application of more than 100 fractions of 2 Gy per day with protons. It is thus theoretically possible to treat patients with protons in such treatment vaults. Nevertheless, the results show that there is a clear need for alternative more efficient energy selection solutions for laser-driven protons.

  8. 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.

  9. Academic Career Selection and Retention in Radiation Oncology: The Joint Center for Radiation Therapy Experience

    International Nuclear Information System (INIS)

    Purpose: The United States healthcare system has witnessed declining reimbursement and increasing documentation requirements for longer than 10 years. These have decreased the time available to academic faculty for teaching and mentorship. The impact of these changes on the career choices of residents is unknown. The purpose of this report was to determine whether changes have occurred during the past decade in the proportion of radiation oncology trainees from a single institution entering and staying in academic medicine. Methods and Materials: We performed a review of the resident employment experience of Harvard Joint Center for Radiation Therapy residents graduating during 13 recent consecutive years (n = 48 residents). The outcomes analyzed were the initial selection of an academic vs. nonacademic career and career changes during the first 3 years after graduation. Results: Of the 48 residents, 65% pursued an academic career immediately after graduation, and 44% remained in academics at the last follow-up, after a median of 6 years. A later graduation year was associated with a decrease in the proportion of graduates immediately entering academic medicine (odds ratio, 0.78; 95% confidence interval, 0.65-0.94). However, the retention rate at 3 years of those who did immediately enter academics increased with a later graduation year (p = 0.03). Conclusion: During a period marked by notable changes in the academic healthcare environment, the proportion of graduating Harvard Joint Center for Radiation Therapy residents pursuing academic careers has been declining; however, despite this decline, the retention rates in academia have increased

  10. Adapting Parent-Child Interaction Therapy to Foster Care

    Science.gov (United States)

    Mersky, Joshua P.; Topitzes, James; Grant-Savela, Stacey D.; Brondino, Michael J.; McNeil, Cheryl B.

    2016-01-01

    Objective: This study presents outcomes from a randomized trial of a novel Parent-Child Interaction Therapy (PCIT) model for foster families. Differential effects of two intervention doses on child externalizing and internalizing symptoms are examined. Method: A sample of 102 foster children was assigned to one of three conditions--brief PCIT,…

  11. Low Level Laser Therapy: laser radiation absorption in biological tissues

    Science.gov (United States)

    Di Giacomo, Paola; Orlando, Stefano; Dell'Ariccia, Marco; Brandimarte, Bruno

    2013-07-01

    In this paper we report the results of an experimental study in which we have measured the transmitted laser radiation through dead biological tissues of various animals (chicken, adult and young bovine, pig) in order to evaluate the maximum thickness through which the power density could still produce a reparative cellular effect. In our experiments we have utilized a pulsed laser IRL1 ISO model (based on an infrared diode GaAs, λ=904 nm) produced by BIOMEDICA s.r.l. commonly used in Low Level Laser Therapy. Some of the laser characteristics have been accurately studied and reported in this paper. The transmission results suggest that even with tissue thicknesses of several centimeters the power density is still sufficient to produce a cell reparative effect.

  12. Head and Neck Soft Tissue Sarcomas Treated with Radiation Therapy

    Science.gov (United States)

    Vitzthum, Lucas K.; Brown, Lindsay C.; Rooney, Jessica W.; Foote, Robert L.

    2016-01-01

    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. PMID:27441072

  13. Carcinoma of the nasal vestibule treated with radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mendenhall, N.P.; Parsons, J.T.; Cassisi, N.J.; Million, R.R.

    1987-05-01

    Twenty-two patients with squamous carcinoma of the nasal vestibule were treated at the University of Florida Division of Radiation Therapy with curative intent. Fifteen lesions were de novo and seven recurrent after surgery. By AJCC classification, 7 lesions were Tx or T1, 2 were T2, 2 were T3, and 11 were T4. Management of the primary tumor and regional lymphatic drainage was highly individualized. Local control was achieved in 19 out of 22 lesions. The ultimate regional lymph node control rate was 22 out of 22, although two patients required radical neck dissection after development of lymph node disease in untreated regional lymphatics. Two patients have died of cancer and three of intercurrent disease. Cosmetic results are generally excellent but may be compromised by previous surgery in recurrent lesions or tumor destruction of normal tissues in advanced lesions. Complications of treatment are minimal.

  14. Efficiency considerations in the expansion of radiation therapy services

    International Nuclear Information System (INIS)

    Purpose: An economic option appraisal to determine whether early investment in capital is an efficient means of expanding radiation therapy services. Methods and Materials: Costs were based on 1991 data from a center in western Sydney. Two options were costed: Option 1 based on an increase in overtime performed by existing staff, using capital more intensively and possible use of shifts; Option 2 based on an investment in new capital and associated increases in levels of staffing. The health sector costs of both options were determined in one center at workloads of between 70,940 and 98,525 fields per year to assess relative efficiency. Results: There was very little difference in cost between both options, with Option 1 slightly cheaper at workloads up to 98,525 fields per year. Conclusions: The results suggest that capital investment may be introduced at a fairly early stage without efficiency loss. Sensitivity analysis reinforces these conclusions and the generalizability of the results

  15. Nutritional support as an adjunct to radiation therapy

    International Nuclear Information System (INIS)

    Patients with malignancies which are treated with therapeutic radiation are at risk for nutritional problems, both from their underlying malignancy as well as from their treatment. These effects may be acute or chronic and relate to the site of the tumor and regions irradiated. There is a large experience with nutritional intervention in irradiated patients, including oral feedings and enteral and parenteral nutritional support. The indications for the specific administration of nutritional support during radiotherapy depend on the nutritional status of the patient and the area irradiated, as well as the individual prognosis. Patients who are malnourished at the time of treatment are most likely to profit from nutritional intervention. To date, prospective randomized trials of nutritional support in patients undergoing radiotherapy fail to show a benefit of routine adjuvant nutritional intervention in terms of improved response and tolerance to treatment, improved local control or survival rates, or reduction of complications from therapy

  16. Laser-radiation therapy failures in stage II laryngeal cancer

    International Nuclear Information System (INIS)

    We have performed laser-radiation combined therapy for stage I and II laryngeal cancers in order to preserve the larynx. In the present study, we retrospectively investigate the factors affecting the preservation of the larynx in stage II laryngeal cancer. The subjects consisted of 34 patients with stage II laryngeal cancer treated between 1988 and 1996 and observed for more than 2 years. Cases with involvement of the ventricle or false cord and those with impaired vocal cord movement showed a tendency towards the loss of their larynx. Moreover, these failures required a longer period to irradiate 1 gray on average than cases which led to a successful preservation of the larynx. (author)

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

    International Nuclear Information System (INIS)

    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

  18. Carcinoma of the nasal vestibule treated with radiation therapy

    International Nuclear Information System (INIS)

    Twenty-two patients with squamous carcinoma of the nasal vestibule were treated at the University of Florida Division of Radiation Therapy with curative intent. Fifteen lesions were de novo and seven recurrent after surgery. By AJCC classification, 7 lesions were Tx or T1, 2 were T2, 2 were T3, and 11 were T4. Management of the primary tumor and regional lymphatic drainage was highly individualized. Local control was achieved in 19 out of 22 lesions. The ultimate regional lymph node control rate was 22 out of 22, although two patients required radical neck dissection after development of lymph node disease in untreated regional lymphatics. Two patients have died of cancer and three of intercurrent disease. Cosmetic results are generally excellent but may be compromised by previous surgery in recurrent lesions or tumor destruction of normal tissues in advanced lesions. Complications of treatment are minimal

  19. Effects of radiation therapy on skeletal growth in childhood

    Energy Technology Data Exchange (ETDEWEB)

    Goldwein, J.W. (Univ. of Pennsylvania School of Medicine, Philadelphia (USA))

    1991-01-01

    Ionizing radiation was used to treat childhood cancer long before the advent of chemotherapy, and it took little time for physicians to appreciate the deleterious effects it had on skeletal growth. The cause of this complication results predominantly from alteration of chondroblastic activity. This may stem directly from irradiation at the epiphyseal plate or indirectly from irradiation of glands that secrete growth-mediating hormones. The complication can go far beyond the obvious physical afflictions and extend into the psychologic domain, rendering deeper, more permanent scars. Presently, many of these effects are predictable, reducible, and treatable without compromising the cure that so often depends on the use of irradiation. Because of the complexities of childhood cancer therapy, strategies aimed at diminishing these effects are challenging. It is imperative that these effects be understood so that they can be reduced in current patients and prevented in future patients.33 references.

  20. External radiation therapy for internal fistulation of malignant obstructive jaundice

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, Yoshikazu; Miyazaki, Minoru; Yasumasa, Keigo; Higuti, Takuya; Hayashi, Hiroki; Iwahashi, Masahiro; Ishikawa, Shirou; Sumimura, Junichi; Nagai, Isao [Kinan General Hospital, Tanabe, Wakayama (Japan)

    1999-03-01

    Internal fistulation is one of way to improve QOL for patients afflicted by malignant obstructive jaundice. Of 15 patients with obstructive jaundice secondary to malignancy in the past three years, percutaneous transhepatic biliary drainage (PTBD) was performed in all cases, and internal fistulation was achieved in six and not in the other nine. Three of successful cases were irradiated with 10 MV x-ray using parallel opposing fields, with average dose of 29 Gy. There were no complaints of vomiting and nausea, pneumonia, or GI bleeding during radiation therapy. For the irradiated cases, it took 52 days from PTBD to fistulation. Internal fistulated patients had no problem with cholangitis or tube trouble, and all were discharged with good QOL. (author)

  1. Hyperbaric Oxygen Therapy in Treating Long-Term Gastrointestinal Adverse Effects Caused by Radiation Therapy in Patients With Pelvic Cancer

    Science.gov (United States)

    2011-07-14

    Bladder Cancer; Cervical Cancer; Colorectal Cancer; Endometrial Cancer; Gastrointestinal Complications; Long-term Effects Secondary to Cancer Therapy in Adults; Ovarian Cancer; Prostate Cancer; Radiation Toxicity; Sarcoma; Testicular Germ Cell Tumor; Vaginal Cancer

  2. Sulfasalazine and temozolomide with radiation therapy for newly diagnosed glioblastoma

    Directory of Open Access Journals (Sweden)

    Satoru Takeuchi

    2014-01-01

    Full Text Available Background: A recent phase 1/2 clinical trial argued for caution for the use of sulfasalazine in progressive glioblastoma (GBM. However, the study enrolled patients with recurrent or progressive high-grade glioma indicating that patients recruited probably had severe disease. Thus, the study may not accurately reflect the effectiveness of sulfasalazine for GBM and we hypothesized that earlier sulfasalazine administration may lead to anticancer effects. Aim: The aim of this study was to investigate whether sulfasalazine can improve the outcomes of patients with newly diagnosed GBM. Subjects and Methods: A total of 12 patients were treated with temozolomide and sulfasalazine with radiation therapy after surgery. Twelve patients with primary GBM treated with temozolomide and radiation therapy formed the control group. Progression-free survival (PFS, overall survival (OS and seizure-free survival (SFS curves were obtained using the Kaplan-Meier method. The survival curves were compared using the log-rank test. Results: The median OS, PFS and SFS did not differ between the groups. Grade 3 or 4 adverse events occurred over the duration of the study in nine (75% patients. The median SFS was 12 months in nine patients who received sulfasalazine administration for more than 21 days, which was strongly but not significantly longer than the 3 months observed in the control group (P = 0.078. Conclusions: Sulfasalazine treatment with temozolomide plus radiotherapy for newly diagnosed primary GBM is associated with a high rate of discontinuation due to hematologic toxic effects. This treatment may have no effect on OS or PFS, although it may improve seizure control if an adequate dose can be administered.

  3. Intensity Modulated Radiation Therapy. Development of the technique

    International Nuclear Information System (INIS)

    Full text: Introduction: Intensity Modulated Radiation Therapy (IMRT) is a result of advances in computer sciences that allowed the development of new technology related to planning and radiation therapy. IMRT was developed to homogenize the dose in the target volumes and decrease the dose in the surrounding healthy tissue. Using a software with high calculation capacity a simultaneous irradiation with different doses in a given volume is achieved. IMRT is based on internal planning. Material and methods: 628 patients were treated with IMRT in prostate lesions, head and neck, breast, thorax, abdomen and brain since August 2008. The software for IMRT is the XIO CMS and the accelerator used is a Varian Clinac 6 / 100. IMRT requires a first simulation, where immobilization systems are selected (mats, thermoplastic masks, among others) and the demarcation of the target structures, healthy tissue and dose prescription by a tattoo. Images of CT / MRI are merged when necessary. Once the system made the treatment optimization, this one is regulated by modulators. These are produced by numerical control machines from digital files produced by software. In a second modulation the planned irradiation is checked and tattoo is carried out according with this. We have a strict process of quality assurance to assess the viability of the plan before its implementation. We use the Map Check it possible to compare the dose on the central axis and the distribution in the whole plane regarding to that generated by the planning system. From 03/2008 the virtual simulation process was implemented integrating the described stages. Results and Conclusions: IMRT is a complex technique. The meticulous planning, implementation of process and quality control allows the use of this technique in a reliable and secure way. With IMRT we achieved a high level of dose conformation, less irradiation of healthy tissue, lower rates of complications and the dose escalation for some tumors. (authors)

  4. Definitions of biochemical failure in prostate cancer following radiation therapy

    International Nuclear Information System (INIS)

    Purpose: The American Society for Therapeutic Radiology and Oncology (ASTRO) published a consensus panel definition of biochemical failure following radiation therapy for prostate cancer. In this paper, we develop a series of alternative definitions of biochemical failure. Using data from 688 patients, we evaluated the sensitivity and specificity of the various definitions, with respect to a defined 'clinically meaningful' outcome. Methods and Materials: The ASTRO definition of biochemical failure requires 3 consecutive rises in prostate-specific antigen (PSA). We considered several modifications to the standard definition: to require PSA rises of a certain magnitude, to consider 2 instead of 3 rises, to require the final PSA value to be greater than a fixed cutoff level, and to define biochemical failure based on the slope of PSA over 1, 1.5, or 2 years. A clinically meaningful failure is defined as local recurrence, distant metastases, initiation of unplanned hormonal therapy, unplanned radical prostatectomy, or a PSA>25 later than 6 months after radiation. Results: Requiring the final PSA in a series of consecutive rises to be larger than 1.5 ng/mL increased the specificity of biochemical failure. For a fixed specificity, defining biochemical failure based on 2 consecutive rises, or the slope over the last year, could increase the sensitivity by up to approximately 20%, compared to the ASTRO definition. Using a rule based on the slope over the previous year or 2 rises leads to a slightly earlier detection of biochemical failure than does the ASTRO definition. Even with the best rule, only approximately 20% of true failures are biochemically detected more than 1 year before the clinically meaningful event time. Conclusion: There is potential for improvement in the ASTRO consensus definition of biochemical failure. Further research is needed, in studies with long follow-up times, to evaluate the relationship between various definitions of biochemical failure and

  5. 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.

  6. Potential of biological images for radiation therapy of cancer

    International Nuclear Information System (INIS)

    Full text: Recent technical advances in 3D conformal and intensity modulated radiotherapy (3DCRT and IMRT) based, on patient-specific CT and MRI images, have the potential of delivering exquisitely conformal dose distributions to the target volume while avoiding critical structures. Emerging clinical results in terms of reducing treatment-related morbidity and increasing local control appear promising. Recent developments in imaging have suggested that biological images may further positively impact cancer diagnosis, characterization and therapy. While in the past radiological images are largely anatomical, the new types of images can provide metabolic, biochemical, physiological, functional and molecular (genotypic and phenotypic) information. For radiation therapy, images that give information about factors (e.g. tumor hypoxia, Tpot) that influence radiosensitivity and treatment outcome can be regarded as radiobiological images. The ability of IMRT to 'paint' (in 2D) or 'sculpt' (in 3D) the dose, and produce exquisitely conformal dose distributions begs the '64 million dollar question' as to how to paint or sculpt, and whether biological imaging may provide the pertinent information. Can this new approach provide 'radiobiological phenotypes' non-invasively, and incrementally improve upon the predictive assays of radiobiological characteristics such as proliferative activity (Tpot - the potential doubling time), radiosensitivity (SF2 - the surviving fraction at a dose of 2 Gy), energy status (relative to sublethal damage repair), pH (a possible surrogate of hypoxia), tumor hypoxia, etc. as prognosticator(s) of radiation treatment outcome. Important for IMRT, the spatial (geometrical) distribution of the radiobiological phenotypes provide the basis for dose distribution design to conform to both the physical (geometrical) and the biological attributes. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

  7. A Systematic Overview of Radiation Therapy Effects in Brain Tumours

    International Nuclear Information System (INIS)

    A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately. This synthesis of the literature on radiation therapy for brain tumours is based on data from 9 randomized trials and 1 meta-analysis. Moreover, data from 2 prospective studies, 3 retrospective studies and 4 other articles were used. In total, 19 scientific articles are included, involving 4,266 patients. The results were compared with those of a similar overview from 1996 including 11,252 patients. The conclusions reached can be summarized as follows: The conclusion from SBU 129/2 that curative treatment is not available for patients with high-grade malignant glioma (grade III and IV) is still valid. The survival benefit from postoperative radiotherapy compared to supportive care only or chemotherapy is about 3-4 months, as demonstrated in earlier randomized studies. Quality of life is now currently estimated and considered to be of major importance when reporting the outcome of treatment for patients with brain tumours. There is no scientific evidence that radiotherapy using hyper- and hypofractionation leads to longer survival for patients with high-grade malignant glioma than conventional radiotherapy. There is large documentation, but only one randomized study. There is some documentation to support the view that patients with grade IV glioma and poor prognosis can be treated with hypofractionation and with an outcome similar to that after conventional fractionation. A shorter treatment time should be convenient for the patient. Documentation of the benefit of a radiotherapy boost with brachytherapy is limited and no conclusion can be drawn. There is no scientific evidence that radiotherapy prolongs life for patients with low-grade glioma. There are some data supporting that radiotherapy can be used to treat symptoms in

  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.

  9. Automated fiducial marker planning for thoracic stereotactic body radiation therapy

    Science.gov (United States)

    Gibbs, Jason D.; Rai, Lav; Wibowo, Henky; Tsalyuk, Serge; Anderson, Eric D.

    2012-02-01

    Stereotactic body-radiation therapy (SBRT) has gained acceptance in treating lung cancer. Localization of a thoracic lesion is challenging as tumors can move significantly with breathing. Some SBRT systems compensate for tumor motion with the intrafraction tracking of targets by two stereo fluoroscopy cameras. However, many lung tumors lack a fluoroscopic signature and cannot be directly tracked. Small radiopaque fiducial markers, acting as fluoroscopically visible surrogates, are instead implanted nearby. The spacing and configuration of the fiducial markers is important to the success of the therapy as SBRT systems impose constraints on the geometry of a fiducial-marker constellation. It is difficult even for experienced physicians mentally assess the validity of a constellation a priori. To address this challenge, we present the first automated planning system for bronchoscopic fiducial-marker placement. Fiducial-marker planning is posed as a constrained combinatoric optimization problem. Constraints include requiring access from a navigable airway, having sufficient separation in the fluoroscopic imaging planes to resolve each individual marker, and avoidance of major blood vessels. Automated fiducial-marker planning takes approximately fifteen seconds, fitting within the clinical workflow. The resulting locations are integrated into a virtual bronchoscopic planning system, which provides guidance to each location during the implantation procedure. To date, we have retrospectively planned over 50 targets for treatment, and have implanted markers according to the automated plan in one patient who then underwent SBRT treatment. To our knowledge, this approach is the first to address automated bronchoscopic fiducialmarker planning for SBRT.

  10. Molecular targeted treatment and radiation therapy for rectal cancer

    International Nuclear Information System (INIS)

    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.)

  11. 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.)

  12. Radiation Therapy in Malignant Tumors of the Parotid Gland

    Energy Technology Data Exchange (ETDEWEB)

    Park, K. R.; Oh, W. Y.; Suh, C. O.; Kim, G. E.; Loh, J. K. [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1986-06-15

    From 1970 to 1982, thirty one patients with malignant tumors of the parotid gland were treated with radiation therapy at department of Radiation Oncology, Yonsei University College of Medicine, Yonsei Cancer Center. Indication for radiotherapy were as follows: 1) when there were microscopic or gross residual diseases (6 patients), 2) when patients considered to have high risk factors (15 patients), 3) when the tumor found to be inoperable (6 patients), 4) when there was recurrence after surgery (4 patients). Most patients were treated with a total of 5,000 to 6,500 cGy in 5 to 6 weeks except when there were gross diseases, in which patients received slightly higher dose up to 7,000 cGy in 7 weeks. Locoregional failure rate was 43% in patients with microscopic or gross residual disease and high risk factors (postoperative radiotherapy group) and 20% in patients with inoperable tumor and recurrence after surgery (primary radiotherapy group). There was no difference in the failure rates among the various histological types. Eight patients failed distantly. Severe complications appeared only in 2 patients irradiated for inoperable advanced diseases.

  13. Results of radiation therapy for squamous cell carcinoma of vulva

    Energy Technology Data Exchange (ETDEWEB)

    Tsukiyama, Iwao; Kakehi, Masae; Ono, Ryosuke (National Cancer Center, Tokyo (Japan). Hospital)

    1984-04-01

    From 1962 to 1982, 20 cases of patients with squamous cell carcinoma of the vulva were treated by radiation alone at National Cancer Center Hospital, Tokyo. 80% (16/20) of these cases were over 60 years old. Treatment was made by interstitial irradiation (Radium needle or Au-Grain) and external irradiation (Betatron electron or Linac X-rays), alone or with various combinations. As for the stage of these cases, Stage I was 3 cases (15%), Stage II was 5 (25%) and Stage III was 12 (60%). Serious complications after treatment were observed in 15% (3/20) and all cases were treated with external irradiation alone. The 5 year survival rates by stage were as follows; Stage I 100% (3/3), Stage II 50% (2/4) and Stage III 22.2% (2/9). Surgery is considered the treatment of choice in this disease. However, radiation therapy may be indicated when the tumor has extended beyond the limit of surgical resections; when distant metastases are present; when the patient's general condition precludes surgery, or when surgery is refused.

  14. Results of radiation therapy for squamous cell carcinoma of vulva

    International Nuclear Information System (INIS)

    From 1962 to 1982, 20 cases of patients with squamous cell carcinoma of the vulva were treated by radiation alone at National Cancer Center Hospital, Tokyo. 80% (16/20) of these cases were over 60 years old. Treatment was made by interstitial irradiation (Radium needle or Au-Grain) and external irradiation (Betatron electron or Linac X-rays), alone or with various combinations. As for the stage of these cases, Stage I was 3 cases (15%), Stage II was 5 (25%) and Stage III was 12 (60%). Serious complications after treatment were observed in 15% (3/20) and all cases were treated with external irradiation alone. The 5 year survival rates by stage were as follows; Stage I 100% (3/3), Stage II 50% (2/4) and Stage III 22.2% (2/9). Surgery is considered the treatment of choice in this disease. However, radiation therapy may be indicated when the tumor has extended beyond the limit of surgical resections; when distant metastases are present; when the patient's general condition precludes surgery, or when surgery is refused. (author)

  15. Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma.

    Science.gov (United States)

    Ebbeskov Lauritsen, Liv; Meidahl Petersen, Peter; Daugaard, Gedske

    2012-05-01

    We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost against the tumour bed) with a conventional fractionation of 2 Gy/day, 5 days per week. RT was applied as hockey-stick portals, also called L-fields. In 2 cases, the symptoms fully resolved. Therapeutic irradiation can cause significant injury to the peripheral nerves of the lumbosacral plexus and/or to the spinal cord. RT is believed to produce plexus injury by both direct toxic effects and secondary microinfarction of the nerves, but the exact pathophysiology of RT-induced injury is unclear. Since reported studies of radiation-induced neurological adverse effects are limited, it is difficult to estimate their frequency and outcome. The treatment of neurological symptoms due to RT is symptomatic. PMID:22949908

  16. Pediatric meuroblastoma: postoperative radiation therapy using less than 2000 rad

    International Nuclear Information System (INIS)

    There is considerable controversy regarding the role of radiaiton therapy in the treatment of neuroblastoma. Postoperative irradiation in the range of 2500-4000 rad is commonly used in the treatment of Evans Stage II or III disease, but there are no data in the literature to suggest the optimum dose of radiation that is necessary. Because much lower doses have been used at the University of Florida, a retrospective study was undertaken in an attempt to determine the optimum dose necessary in conjunction with surgery. From March 1964 through July 1979, 21 children with Stage II or III neuroblastoma were seen at the University of Florida. One patient died postoperatively. The remainder received postoperative irradiation with doses ranging from 900 to 4500 rad. The lower dose of radiation used did not adversely influence survival, particularly for patients less than two years of age diagnosis. In this group, no patient had a local recurrence or died of disease, even though nine of 15 available patients received doses of 900-1500 rad

  17. Pediatric meuroblastoma: postoperative radiation therapy using less than 2000 rad

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, H.M.; Marcus, R.B. Jr; Thar, T.L.; Million, R.R.; Graham-Pole, J.R.; Talbert, J.L.

    1983-04-01

    There is considerable controversy regarding the role of radiaiton therapy in the treatment of neuroblastoma. Postoperative irradiation in the range of 2500-4000 rad is commonly used in the treatment of Evans Stage II or III disease, but there are no data in the literature to suggest the optimum dose of radiation that is necessary. Because much lower doses have been used at the University of Florida, a retrospective study was undertaken in an attempt to determine the optimum dose necessary in conjunction with surgery. From March 1964 through July 1979, 21 children with Stage II or III neuroblastoma were seen at the University of Florida. One patient died postoperatively. The remainder received postoperative irradiation with doses ranging from 900 to 4500 rad. The lower dose of radiation used did not adversely influence survival, particularly for patients less than two years of age diagnosis. In this group, no patient had a local recurrence or died of disease, even though nine of 15 available patients received doses of 900-1500 rad.

  18. Widespread adaptive evolution during repeated evolutionary radiations in New World lupins

    Science.gov (United States)

    Nevado, Bruno; Atchison, Guy W.; Hughes, Colin E.; Filatov, Dmitry A.

    2016-01-01

    The evolutionary processes that drive rapid species diversification are poorly understood. In particular, it is unclear whether Darwinian adaptation or non-adaptive processes are the primary drivers of explosive species diversifications. Here we show that repeated rapid radiations within New World lupins (Lupinus, Leguminosae) were underpinned by a major increase in the frequency of adaptation acting on coding and regulatory changes genome-wide. This contrasts with far less frequent adaptation in genomes of slowly diversifying lupins and all other plant genera analysed. Furthermore, widespread shifts in optimal gene expression coincided with shifts to high rates of diversification and evolution of perenniality, a putative key adaptation trait thought to have triggered the evolutionary radiations in New World lupins. Our results reconcile long-standing debate about the relative importance of protein-coding and regulatory evolution, and represent the first unambiguous evidence for the rapid onset of lineage- and genome-wide accelerated Darwinian evolution during rapid species diversification. PMID:27498896

  19. Radiation therapy for the palliation of multiple myeloma

    International Nuclear Information System (INIS)

    This study reviews the experience at the University of Arizona in an effort to define the minimum effective radiation dose for durable pain relief in the majority of patients with symptomatic multiple myeloma. The records of 101 patients with multiple myeloma irradiated for palliation at the University of Arizona between 1975 and 1990 were reviewed. Three hundred sixteen sites were treated. Ten sites were asymptomatic, including six hemibody fields with advanced disease unresponsive to chemotherapy and four local fields with impending pathological fractures. Three hundred six evaluable symptomatic sites remained. The most common symptom was bone pain. Other symptoms included neurological impairment with a palpable mass. Total tumor dose ranged from 3.0 to 60 Gy, with a mean of 25 Gy. Symptom relief was obtained in 297 of 306 evaluable symptomatic sites (97%). Complete relief of symptoms was obtained in 26% and partial relief in 71%. Symptom relief was obtained in 92% of sites receiving a total dose less than 10 Gy (n = 13) and 98% of sites receiving 10 Gy or more (n = 293). No dose-response could be demonstrated. The likelihood of symptom relief was not influenced by the location of the lesion or the use of concurrent chemotherapy. Of the 297 responding sites, 6% (n = 19) relapsed after a median symptom-free interval of 16 months. Neither the probability of relapse nor the time to relapse was related to the radiation dose. Retreatment of relapsing sites provided effective palliation in all cases. Radiation therapy is effective in palliating local symptoms in multiple myeloma. A total dose of 10 Gy should provide durable symptom relief in the majority of patients. 16 refs., 3 figs., 4 tabs

  20. Stroke-like Migraine Attacks after Radiation Therapy Syndrome

    Institute of Scientific and Technical Information of China (English)

    Qian Zheng; Li Yang; Li-Ming Tan; Li-Xia Qin; Chun-Yu Wang; Hai-Nan Zhang

    2015-01-01

    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 angiography.

  1. Long-term outcomes for adult craniopharyngioma following radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Masson-Cote, Laurence; Masucci, Giuseppina Laura; Millar, Barbara-Ann; Laperriere, Normand J. [Dept. of Radiation Oncology, Princess Margaret Hospital, Univ. of Toronto, Toronto (Canada); Atenafu, Eshetu G. [Dept. of Biostatistics, Princess Margaret Hospital, Univ. of Toronto, Toronto (Canada); Cusimano, Michael [Dept. of Surgery, Div. of Neurosurgery, St. Michaels Hospital, Toronto (Canada); Croul, Sidney [Dept. of Pathology, Univ. of Toronto, Toronto (Canada); Mason, Warren [Dept. of Medicine, Princess Margaret Hospital, Univ. of Toronto, Toronto (Canada); Sahgal, Arjun [Dept. of Radiation Oncology, Princess Margaret Hospital, Univ. of Toronto, Toronto (Canada), E-mail: Arjun.sahgal@rmp.uhn.on.ca; Dept. of Radiation Oncology, Sunnybrook Health Sciences Center, Univ. of Toronto, Toronto (Canada)

    2013-01-15

    Background. We report long-term outcomes in adult patients with craniopharyngioma following surgery and radiation therapy (RT). Material and methods. Fifty-three patients treated with RT (median, 50 Gy in 25 fractions) between 1980 and 2009 with pathologically confirmed craniopharyngioma were reviewed (53% solid and 47% cystic/solid). The median age was 53 years (range, 22-76), 53% were female, 83% were sub-totally resected, 6% were gross totally resected and 11% had a biopsy and/or cyst aspiration alone. RT was delivered adjuvantly in 53% of patients as opposed to salvage intent upon progression. Results. Median follow-up was seven years (86 months, range, 8-259). The 5- and 10-year progression-free survival (PFS) rates were 85% and 69%, overall survival (OS) rates were 76% and 70%, and cause-specific survival (CSS) rates were both 88%, respectively. Both univariable and multivariable analysis identified age (<53 or {>=}53) as a prognostic factor for OS (p =0.0003) and CSS (p =0.05). PFS was observed to be worse in patients with >2 surgeries prior to RT (p =0.01). Neither the intent of radiation or tumor type (cystic vs. solid/cystic) were prognostic or predictive. New endocrinopathies and visual dysfunction were observed in 53% and 17% of patients post-surgery, and in 11% and 6% post-RT, respectively. Conclusion. We report long-term favorable PFS, CSS and OS for craniopharyngioma post-RT. We observe age as a significant prognostic factor, however, timing of radiation was not.

  2. 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 892.5900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5900 X-ray radiation therapy...

  3. 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 Section 892.5710 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5710 Radiation therapy...

  4. An Evaluation of Dose Equivalence between Synchrotron Microbeam Radiation Therapy and Conventional Broadbeam Radiation Using Clonogenic and Cell Impedance Assays

    OpenAIRE

    Mohammad Johari Ibahim; Crosbie, Jeffrey C.; Yuqing Yang; Marina Zaitseva; Andrew W Stevenson; Rogers, Peter A. W.; Premila Paiva

    2014-01-01

    BACKGROUND: High-dose synchrotron microbeam radiation therapy (MRT) has shown the potential to deliver improved outcomes over conventional broadbeam (BB) radiation therapy. To implement synchrotron MRT clinically for cancer treatment, it is necessary to undertake dose equivalence studies to identify MRT doses that give similar outcomes to BB treatments. AIM: To develop an in vitro approach to determine biological dose equivalence between MRT and BB using two different cell-based assays. METHO...

  5. 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.

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

    International Nuclear Information System (INIS)

    Background and purpose: 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. Material and methods: 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. Results: Borders of the CTV encompassing a 5 mm 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. Conclusion: 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

  7. 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.

  8. 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 th

  9. 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.

  10. Dosimetric comparison of three dimensional conformal radiation therapy versus intensity modulated radiation therapy in accelerated partial breast irradiation

    Directory of Open Access Journals (Sweden)

    S Moorthy

    2016-01-01

    Full Text Available Aim of Study: Breast conserving surgery (BCS is the standard treatment for stage I and II breast cancer. Multiple studies have shown that recurrences after lumpectomy occur mainly in or near the tumor bed. Use of accelerated partial breast irradiation (APBI allows for significant reduction in the overall treatment time that results in increasing patient compliance and decreasing healthcare costs. We conducted a treatment planning study to evaluate the role of intensity modulated radiation therapy (IMRT with regards to three-dimensional conformal radiation therapy (3DCRT in APBI. Materials and Methods: Computed tomography planning data sets of 33 patients (20 right sided and 13 left sided with tumor size less than 3 cm and negative axillary lymph nodes were used for our study. Tumor location was upper outer, upper inner, central, lower inner, and lower outer quadrants in 10, 10, 5, 4 and 4 patients, respectively. Multiple 3DCRT and IMRT plans were created for each patient. Total dose of 38.5 Gy in 10 fractions were planned. Dosimetric analysis was done for the best 3DCRT and IMRT plans. Results: The target coverage has been achieved by both the methods but IMRT provided better coverage (P = 0.04 with improved conformity index (P = 0.01. Maximum doses were well controlled in IMRT to below 108% (P < 0.01. Heart V2 Gy (P < 0.01, lung V5 Gy (P = 0.01, lung V10 Gy (P = 0.02, contralateral breast V1 Gy (P < 0.01, contralateral lung V2 Gy (P < 0.01, and ipsilateral uninvolved breast (P < 0.01 doses were higher with 3DCRT compared to IMRT. Conclusion: Dosimetrically, IMRT–APBI provided best target coverage with less dose to normal tissues compared with 3DCRT-APBI.

  11. 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.

  12. 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.

  13. A Patterns of Care Study of the Various Radiation Therapies for Prostate Cancer among Korean Radiation Oncologists in 2006

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Hee [Keimyung Univ., Daegu (Korea, Republic of); Kim, Jae Sung; Ha, Sung Whan [Seoul National University College of Medicine, Seoul (Korea, Republic of)] (and others)

    2008-06-15

    To conduct a nationwide academic hospital patterns of the practice status and principles of radiotherapy for prostate cancer. The survey will help develop the framework of a database of Korean in Patterns of Case Study. A questionnaire about radiation treatment status and principles was sent to radiation oncologists in charge of prostate cancer treatment at thirteen academic hospitals in Korea. The data was analyzed to find treatment principles among the radiation oncologists when treating prostate cancer. The number of patients with prostate cancer and treated with radiation ranged from 60 to 150 per academic hospital in Seoul City and 10 to 15 outside of Seoul City in 2006. The primary diagnostic methods of prostate cancer included the ultrasound guided biopsy on 6 to 12 prostate sites (mean=9), followed by magnetic resonance imaging and a whole body bone scan. Internal and external immobilizations were used in 61.5% and 76.9%, respectively, with diverse radiation targets. Whole pelvis radiation therapy (dose ranging from 45.0 to 50.4 Gy) was performed in 76.9%, followed by the irradiation of seminal vesicles (54.0{approx}73.8 Gy) in 92.3%. The definitive radiotherapy doses were increased as a function of risk group, but the range of radiation doses was wide (60.0 to 78.5 Gy). Intensity modulated radiation therapy using doses greater than 70 Gy, were performed in 53.8% of academic hospitals. In addition, the simultaneous intra-factional boost (SIB) technique was used in three hospitals; however, the target volume and radiation dose were diverse. Radiation therapy to biochemical recurrence after a radical prostatectomy was performed in 84.6%; however, the radiation dose was variable and the radiation field ranged from whole pelvis to prostate bed. The results of this study suggest that a nationwide Korean Patterns of Care Study is necessary for the recommendation of radiation therapy guidelines of prostate cancer.

  14. 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.

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

    International Nuclear Information System (INIS)

    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. Adapted physical activity in the prevention and therapy of osteoporosis

    Directory of Open Access Journals (Sweden)

    Bošković Ksenija

    2013-01-01

    Full Text Available Introduction. Osteoporosis, a disease characterized by the progressive loss of bone tissue, is one of the most common complications of aging. Epidemiology. According to some calculations, there were 25% of women and 4% of men older than 50 years with osteoporosis in the world in 2010. It is assumed that the number of patients with osteoporosis will increase by 30% in every 10 years in the 21st century. There are many reasons for that: the world’s population is growing older, diet is getting poorer in vitamins and minerals and physical activity is decreasing. The Quality and Quantity of Bone Tissue. Developing bones are much more responsive to mechanical loading and physical activity than mature bones. This suggests that training in early childhood may be an important factor in the prevention of osteoporosis in later life. It is important to note that the quality of bone achieved by training at younger age cannot be maintained permanently if it is not supported by physical activity later in life. Adapted physical activity represents physical activity individually tailored according to the psychosomatic capabilities of a person and the goal to be achieved. It can be applied at any age in order to maintain strong bones and reduce the risk of fracture. Adapted physical activity is different for men and women, for different age, as well as for the individuals. Aerobic exercises, which lead to an acceleration of breathing, increased heart rate and mild perspiration, as well as resistance exercises and exercises against resistance done by stretching elastic bands, for hands, legs and torso have been proven to increase bone density and improve bone strength. Coordination and balance exercises are important in an individual workout program. An explanation of the action of adapted physical activity is the basis for the theory of control and modulation of bone loss, muscle strength, coordination and balance. Physical activity is very effective in

  17. Effect of radiation therapy on autologous and allogeneic bone grafts

    International Nuclear Information System (INIS)

    Purpose: Currently no significant literature exists regarding the effects of therapeutic radiation on bone graft integrity in humans. As the combination of these procedures is frequently necessary in the treatment of neoplasms, we have retrospectively analyzed graft outcomes in irradiated sites. Materials and Methods: 40 autologous or allogeneic bone grafts in 35 patients treated at the Massachusetts General Hospital (MGH) between 1977 and 1995 were evaluated. Preoperative radiation was given in 28 cases, postoperative in 21 cases. Radiation was delivered as external beam photons, 160 MeV protons or brachytherapy implant. Doses ranged from 3 to 83 Gy. Grafts were located in the spine (17), pelvis (13), femur (5), humerus (2) and tibia (3). Functional graft survival and healing quality were determined radiographically. Failure free survival rates were calculated using the Kaplan-Meier method and linear regressions were performed using the Wilcoxan method. Results: Overall rates of graft survival were 86% at 1 yr and 73% at 5 yrs. For auto grafts and allografts the 1 yr rates were 100% and 80% (p=.96). No significant differences in outcome based on treatment chronology were found with survival rates of 81% for preoperative treatment and 86% for postoperative treatment. With linear regression analysis there was no relation between outcome and time between surgery and radiation (p=.89). Further, no relation between bone dose (preoperative + postoperative dose), graft dose (postoperative dose) or mean dose/day and outcome was found (p=.50, p=.49 and p=.43). Failures were evenly distributed amongst high and low dose groups. The use of chemotherapy did not significantly effect outcome with a survival rate of 85% compared to 87%. Tobacco use was a significant predictor of failure with 63% graft survival compared to 94% in non-smokers (p=.038). Quality of bone healing rated poor overall, but was highly variable and did not correlate with dose or chronology of therapy

  18. 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 inv