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Sample records for adaptive radiation therapy

  1. Clinical Implementation Of Adaptive Radiation Therapy

    In radiotherapy, treatment position error has been one of the major limits in either increasing treatment conformality or decreasing the marginal misses. There have been two strategies to reduce the effect of treatment position error on tumor treatment. The first one incorporates the possible uncertainties into pretreatment planning to demonstrate the effects of dose variation. The second strategy establishes different decision rules to reduce the magnitude of position error by repositioning the patients. This has been investigated by many researchers due to the advent of electronic portal imaging devices. Another strategy may be beneficial to the radiation treatment outcome, which we have termed 'adaptive radiotherapy'. Initially, adaptive radiotherapy uses patient population data to identify the sensitivity of different treatment sites to positional variation. Then, it uses the position error measured from each individual patient during the process of treatment delivery to adaptively modify the treatment parameters. For example, the MLC field can be reshaped to improve the treatment through either increasing possibility of dose escalation or reducing a possibility of the marginal misses. Our work demonstrates how to use an on-line imaging system and a MLC to implement this adaptive process in the radiotherapy clinic. The practical considerations and requirements (computer software, hardware and networks) are also discussed. A retrospective study for prostate and lung treatments is used to demonstrate the potential gain from this procedure

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

    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...

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

    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

  4. Direct aperture optimization for online adaptive radiation therapy

    This paper is the first investigation of using direct aperture optimization (DAO) for online adaptive radiation therapy (ART). A geometrical model representing the anatomy of a typical prostate case was created. To simulate interfractional deformations, four different anatomical deformations were created by systematically deforming the original anatomy by various amounts (0.25, 0.50, 0.75, and 1.00 cm). We describe a series of techniques where the original treatment plan was adapted in order to correct for the deterioration of dose distribution quality caused by the anatomical deformations. We found that the average time needed to adapt the original plan to arrive at a clinically acceptable plan is roughly half of the time needed for a complete plan regeneration, for all four anatomical deformations. Furthermore, through modification of the DAO algorithm the optimization search space was reduced and the plan adaptation was significantly accelerated. For the first anatomical deformation (0.25 cm), the plan adaptation was six times more efficient than the complete plan regeneration. For the 0.50 and 0.75 cm deformations, the optimization efficiency was increased by a factor of roughly 3 compared to the complete plan regeneration. However, for the anatomical deformation of 1.00 cm, the reduction of the optimization search space during plan adaptation did not result in any efficiency improvement over the original (nonmodified) plan adaptation. The anatomical deformation of 1.00 cm demonstrates the limit of this approach. We propose an innovative approach to online ART in which the plan adaptation and radiation delivery are merged together and performed concurrently--adaptive radiation delivery (ARD). A fundamental advantage of ARD is the fact that radiation delivery can start almost immediately after image acquisition and evaluation. Most of the original plan adaptation is done during the radiation delivery, so the time spent adapting the original plan does not

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

    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

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

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

    2014-09-01

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

  7. Adaptive Stereotactic Body Radiation Therapy Planning for Lung Cancer

    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.

  8. Auto-propagation of contours for adaptive prostate radiation therapy

    Chao, Ming; Xie, Yaoqin; Xing, Lei

    2008-09-01

    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.

  9. Auto-propagation of contours for adaptive prostate radiation therapy.

    Chao, Ming; Xie, Yaoqin; Xing, Lei

    2008-09-01

    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. PMID:18677041

  10. Auto-propagation of contours for adaptive prostate radiation therapy

    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

  11. Determining appropriate timing of adaptive radiation therapy for nasopharyngeal carcinoma during intensity-modulated radiation therapy

    To determine appropriate timing of an adaptive radiation therapy (ART) replan by evaluating anatomic and dosimetric changes of target volumes and organs at risk (OARs) during intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC). Nineteen NPC patients were recruited. Each patient had repeat computed tomography (CT) scans after each five fractions and at treatment completion. Automatic re-contouring the targets and OARs by using deformable registration algorithm was conducted through CT-CT fusion. Anatomic changes were assessed by comparing the initial CT and repeated CT. Hybrid plans with re-contouring were generated and the dose-volume histograms (DVH) of the hybrid plan and the original plan were compared. Progressive volume reductions in gross target volume for primary disease (GTVnx), gross target volume for involved lymph nodes (GTVnd), and parotids were observed over time. Comparing with the original plan, each hybrid plan had no significant difference in homogeneity index (HI) for all the targets. Some parameters for planning target volumes for primary disease and high-risk clinical target volume (PTVnx and PTV1, respectively) improved significantly, notably starting from the 10th fraction. These parameters included mean dose (Dmean), dose to 95 % of the volume (D95), percentage of the volume receiving 95 % of the prescription dose (V95), and conformity index (CI) for PTVnx, and Dmean, D95, and CI for PTV1. The dosimetric parameters for PTVnd remained the same in general except for D95 and V95 which had significant improvement at specific time points; whereas for PTV2, similar trend of dosimetric changes was also observed. Dose to some OARs increased significantly at some time points. There were significant anatomic and dosimetric changes in the targets and OARs. The target dose coverage in the hybrid plans did not get worse, but overdose occurred in some critical structures. Significant dosimetric changes should be considered as a

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

    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

  13. Developing an adaptive radiation therapy strategy for nasopharyngeal carcinoma

    Adaptive radiotherapy (ART) has recently been introduced to restore the planned dose distribution by accounting for the anatomic changes during treatment. By quantifying the anatomic changes in nasopharyngeal carcinoma (NPC) patients, this study aimed to establish an ART strategy for NPC cases. A total of 30 NPC patients treated with helical tomotherapy were recruited. In the pretreatment megavoltage CT images, the anatomic changes of the posterolateral wall of nasopharynx (P-NP), neck region and parotid glands were measured and assessed. One-way repeated measure ANOVA was employed to define threshold(s) at any time-point. The presence of a threshold(s) would indicate significant anatomical change(s) such that replanning should be suggested. A pragmatic schedule for ART was established by evaluating the threshold for each parameter. Results showed the P-NP, parotid gland and neck volumes demonstrated significant regressions over time. Respectively, the mean loss rates were 0.99, 1.35, and 0.39 %/day, and the mean volume losses were 35.70, 47.54 and 11.91% (all P < 0.001). The parotid gland shifted medially and superiorly over time by a mean of 0.34 and 0.24 cm, respectively (all P < 0.001). The neck region showed non-rigid posterior displacement, which increased from upper to lower neck. According to the threshold occurrences, three replans at 9th, 19th and 29th fractions were proposed. This ART strategy was able to accommodate the dosimetric consequences due to anatomic deviation over the treatment course. It is clinically feasible and would be recommended for centers where an adaptive planning system was not yet available. (author)

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

    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

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

    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

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

    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.

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

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

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

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

    2012-07-01

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

  19. Radiation Therapy

    ... 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 ...

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

    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

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

    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

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

    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.

  3. Formulating adaptive radiation therapy (ART) treatment planning into a closed-loop control framework

    While ART has been studied for years, the specific quantitative implementation details have not. In order for this new scheme of radiation therapy (RT) to reach its potential, an effective ART treatment planning strategy capable of taking into account the dose delivery history and the patient's on-treatment geometric model must be in place. This paper performs a theoretical study of dynamic closed-loop control algorithms for ART and compares their utility with data from phantom and clinical cases. We developed two classes of algorithms: those Adapting to Changing Geometry and those Adapting to Geometry and Delivered Dose. The former class takes into account organ deformations found just before treatment. The latter class optimizes the dose distribution accumulated over the entire course of treatment by adapting at each fraction, not only to the information just before treatment about organ deformations but also to the dose delivery history. We showcase two algorithms in the class of those Adapting to Geometry and Delivered Dose. A comparison of the approaches indicates that certain closed-loop ART algorithms may significantly improve the current practice. We anticipate that improvements in imaging, dose verification and reporting will further increase the importance of adaptive algorithms

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

    Online adaptive radiation therapy (ART) has great promise to significantly reduce normal tissue toxicity and/or improve tumor control through real-time treatment adaptations based on the current patient anatomy. However, the major technical obstacle for clinical realization of online ART, namely the inability to achieve real-time efficiency in treatment re-planning, has yet to be solved. To overcome this challenge, this paper presents our work on the implementation of an intensity-modulated radiation therapy (IMRT) direct aperture optimization (DAO) algorithm on the graphics processing unit (GPU) based on our previous work on the CPU. We formulate the DAO problem as a large-scale convex programming problem, and use an exact method called the column generation approach to deal with its extremely large dimensionality on the GPU. Five 9-field prostate and five 5-field head-and-neck IMRT clinical cases with 5 x 5 mm2 beamlet size and 2.5 x 2.5 x 2.5 mm3 voxel size were tested to evaluate our algorithm on the GPU. It takes only 0.7-3.8 s for our implementation to generate high-quality treatment plans on an NVIDIA Tesla C1060 GPU card. Our work has therefore solved a major problem in developing ultra-fast (re-)planning technologies for online ART.

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

    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...

  6. Automatic Segmentation and Online virtualCT in Head-and-Neck Adaptive Radiation Therapy

    Purpose: The purpose of this work was to develop and validate an efficient and automatic strategy to generate online virtual computed tomography (CT) scans for adaptive radiation therapy (ART) in head-and-neck (HN) cancer treatment. Method: We retrospectively analyzed 20 patients, treated with intensity modulated radiation therapy (IMRT), for an HN malignancy. Different anatomical structures were considered: mandible, parotid glands, and nodal gross tumor volume (nGTV). We generated 28 virtualCT scans by means of nonrigid registration of simulation computed tomography (CTsim) and cone beam CT images (CBCTs), acquired for patient setup. We validated our approach by considering the real replanning CT (CTrepl) as ground truth. We computed the Dice coefficient (DSC), center of mass (COM) distance, and root mean square error (RMSE) between correspondent points located on the automatically segmented structures on CBCT and virtualCT. Results: Residual deformation between CTrepl and CBCT was below one voxel. Median DSC was around 0.8 for mandible and parotid glands, but only 0.55 for nGTV, because of the fairly homogeneous surrounding soft tissues and of its small volume. Median COM distance and RMSE were comparable with image resolution. No significant correlation between RMSE and initial or final deformation was found. Conclusion: The analysis provides evidence that deformable image registration may contribute significantly in reducing the need of full CT-based replanning in HN radiation therapy by supporting swift and objective decision-making in clinical practice. Further work is needed to strengthen algorithm potential in nGTV localization.

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

    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

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

    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.

  9. Multiscale registration of planning CT and daily cone beam CT images for adaptive radiation therapy

    Adaptive radiation therapy (ART) is the incorporation of daily images in the radiotherapy treatment process so that the treatment plan can be evaluated and modified to maximize the amount of radiation dose to the tumor while minimizing the amount of radiation delivered to healthy tissue. Registration of planning images with daily images is thus an important component of ART. In this article, the authors report their research on multiscale registration of planning computed tomography (CT) images with daily cone beam CT (CBCT) images. The multiscale algorithm is based on the hierarchical multiscale image decomposition of E. Tadmor, S. Nezzar, and L. Vese [Multiscale Model. Simul. 2(4), pp. 554-579 (2004)]. Registration is achieved by decomposing the images to be registered into a series of scales using the (BV, L2) decomposition and initially registering the coarsest scales of the image using a landmark-based registration algorithm. The resulting transformation is then used as a starting point to deformably register the next coarse scales with one another. This procedure is iterated at each stage using the transformation computed by the previous scale registration as the starting point for the current registration. The authors present the results of studies of rectum, head-neck, and prostate CT-CBCT registration, and validate their registration method quantitatively using synthetic results in which the exact transformations our known, and qualitatively using clinical deformations in which the exact results are not known.

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

    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)

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

    Altman, M. B.; Kavanaugh, J. A.; Wooten, H. O.; Green, O. L.; DeWees, T. A.; Gay, H.; Thorstad, W. L.; Li, H.; Mutic, S.

    2015-07-01

    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.

  12. Beam orientation optimization for intensity modulated radiation therapy using adaptive l2,1-minimization

    Jia, Xun; Men, Chunhua; Lou, Yifei; Jiang, Steve B.

    2011-10-01

    Beam orientation optimization (BOO) is a key component in the process of intensity modulated radiation therapy treatment planning. It determines to what degree one can achieve a good treatment plan in the subsequent plan optimization process. In this paper, we have developed a BOO algorithm via adaptive l2, 1-minimization. Specifically, we introduce a sparsity objective function term into our model which contains weighting factors for each beam angle adaptively adjusted during the optimization process. Such an objective function favors a small number of beam angles. By optimizing a total objective function consisting of a dosimetric term and the sparsity term, we are able to identify unimportant beam angles and gradually remove them without largely sacrificing the dosimetric objective. In one typical prostate case, the convergence property of our algorithm, as well as how beam angles are selected during the optimization process, is demonstrated. Fluence map optimization (FMO) is then performed based on the optimized beam angles. The resulting plan quality is presented and is found to be better than that of equiangular beam orientations. We have further systematically validated our algorithm in the contexts of 5-9 coplanar beams for five prostate cases and one head and neck case. For each case, the final FMO objective function value is used to compare the optimized beam orientations with the equiangular ones. It is found that, in the majority of cases tested, our BOO algorithm leads to beam configurations which attain lower FMO objective function values than those of corresponding equiangular cases, indicating the effectiveness of our BOO algorithm. Superior plan qualities are also demonstrated by comparing DVH curves between BOO plans and equiangular plans.

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

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

  14. Dosimetric and Radiobiological Consequences of Computed Tomography–Guided Adaptive Strategies for Intensity Modulated Radiation Therapy of the Prostate

    Purpose: To examine a range of scenarios for image-guided adaptive radiation therapy of prostate cancer, including different schedules for megavoltage CT imaging, patient repositioning, and dose replanning. Methods and Materials: We simulated multifraction dose distributions with deformable registration using 35 sets of megavoltage CT scans of 13 patients. We computed cumulative dose–volume histograms, from which tumor control probabilities and normal tissue complication probabilities (NTCPs) for rectum were calculated. Five-field intensity modulated radiation therapy (IMRT) with 18-MV x-rays was planned to achieve an isocentric dose of 76 Gy to the clinical target volume (CTV). The differences between D95, tumor control probability, V70Gy, and NTCP for rectum, for accumulated versus planned dose distributions, were compared for different target volume sizes, margins, and adaptive strategies. Results: The CTV D95 for IMRT treatment plans, averaged over 13 patients, was 75.2 Gy. Using the largest CTV margins (10/7 mm), the D95 values accumulated over 35 fractions were within 2% of the planned value, regardless of the adaptive strategy used. For tighter margins (5 mm), the average D95 values dropped to approximately 73.0 Gy even with frequent repositioning, and daily replanning was necessary to correct this deficit. When personalized margins were applied to an adaptive CTV derived from the first 6 treatment fractions using the STAPLE (Simultaneous Truth and Performance Level Estimation) algorithm, target coverage could be maintained using a single replan 1 week into therapy. For all approaches, normal tissue parameters (rectum V70Gy and NTCP) remained within acceptable limits. Conclusions: The frequency of adaptive interventions depends on the size of the CTV combined with target margins used during IMRT optimization. The application of adaptive target margins (<5 mm) to an adaptive CTV determined 1 week into therapy minimizes the need for subsequent dose

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

    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....

  16. The use of adaptive radiation therapy to reduce setup error: a prospective clinical study

    Purpose: Adaptive Radiation Therapy (ART) is a closed-loop feedback process where each patients treatment is adaptively optimized according to the individual variation information measured during the course of treatment. The process aims to maximize the benefits of treatment for the individual patient. A prospective study is currently being conducted to test the feasibility and effectiveness of ART for clinical use. The present study is limited to compensating the effects of systematic setup error. Methods and Materials: The study includes 20 patients treated on a linear accelerator equipped with a computer controlled multileaf collimator (MLC) and a electronic portal imaging device (EPID). Alpha cradles are used to immobilize those patients treated for disease in the thoracic and abdominal regions, and thermal plastic masks for the head and neck. Portal images are acquired daily. Setup error of each treatment field is quantified off-line every day. As determined from an earlier retrospective study of different clinical sites, the measured setup variation from the first 4 to 9 days, are used to estimate systematic setup error and the standard deviation of random setup error for each field. Setup adjustment is made if estimated systematic setup error of the treatment field was larger than or equal to 2 mm. Instead of the conventional approach of repositioning the patient, setup correction is implemented by reshaping MLC to compensate for the estimated systematic error. The entire process from analysis of portal images to the implementation of the modified MLC field is performed via computer network. Systematic and random setup errors of the treatment after adjustment are compared with those prior to adjustment. Finally, the frequency distributions of block overlap cumulated throughout the treatment course are evaluated. Results: Sixty-seven percent of all treatment fields were reshaped to compensate for the estimated systematic errors. At the time of this writing

  17. The use of adaptive radiation therapy to reduce setup error: a prospective clinical study

    Purpose: Adaptive Radiation Therapy (ART) is a feedback treatment process that optimizes a patient's treatment according to the patient specific information measured during the course of treatment. Utilizing an electronic portal imaging device (EPID) and a computer-controlled multileaf collimator (MLC), the ART process is currently being implemented in our clinic to improve the treatment accuracy by compensating for the treatment setup error. A prospective study was conducted to evaluate the feasibility and efficacy of the ART process for clinical use. Methods and Materials: The prospective study included 20 patients who underwent conventional radiotherapy on a linear accelerator equipped with an EPID and a MLC. No specific changes were made in the routine clinical procedures except daily portal images were obtained for each treatment field. Two-dimensional setup error for each treatment field was then measured offline using a software tool. The measured setup errors from initial treatment days were used to predict the systematic and random setup errors for each treatment field. An adjustment decision was made if the predicted systematic error was larger than or equal to 2 mm. Furthermore, the treatment field was extended if the predicted random setup error could not be effectively compensated by the predefined treatment setup margin. Instead of the conventional approach of patient repositioning, setup adjustment was implemented by reshaping the MLC field. The entire process from measuring setup error to reshaping the MLC field was performed offline through a computer network. After completion of a patient's treatment, the systematic and random setup errors after adjustment were compared with those predicted prior to the adjustment. The accuracy of the adjustment, and the reliability and stability of the process were analyzed. Results: Treatment fields of 13 patients were modified to correct for systematic errors. The mean systematic error was 4 mm with a range of

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

    Court, Laurence E; Tishler, Roy B; Petit, Joshua; Cormack, Robert; Chin Lee [Department of Radiation Oncology, Dana-Farber/Brigham and Women' s Hospital Cancer Center, 75 Francis Street, ASBI-L2, Boston, MA 02115 (United States)

    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 deg, 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

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

    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.

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

    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.

  1. Radiation Therapy

    ... 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' ...

  2. Adaptive Radiation for Lung Cancer

    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.

  3. Deformable registration of the planning image (kVCT) and the daily images (MVCT) for adaptive radiation therapy

    The incorporation of daily images into the radiotherapy process leads to adaptive radiation therapy (ART), in which the treatment is evaluated periodically and the plan is adaptively modified for the remaining course of radiotherapy. Deformable registration between the planning image and the daily images is a key component of ART. In this paper, we report our researches on deformable registration between the planning kVCT and the daily MVCT image sets. The method is based on a fast intensity-based free-form deformable registration technique. Considering the noise and contrast resolution differences between the kVCT and the MVCT, an 'edge-preserving smoothing' is applied to the MVCT image prior to the deformable registration process. We retrospectively studied daily MVCT images from commercial TomoTherapy machines from different clinical centers. The data set includes five head-neck cases, one pelvis case, two lung cases and one prostate case. Each case has one kVCT image and 20-40 MVCT images. We registered the MVCT images with their corresponding kVCT image. The similarity measures and visual inspections of contour matches by physicians validated this technique. The applications of deformable registration in ART, including 'deformable dose accumulation', 'automatic re-contouring' and 'tumour growth/regression evaluation' throughout the course of radiotherapy are also studied

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

    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.

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

    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.

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

    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

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

    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

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

    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.

  9. External Radiation Therapy

    Full Text Available ... older the treatment that is frequently used is radiation therapy. Gunnar Zagars, M.D.: There are different forms ... prostate. [beeping] Narrator: The more common form of radiation therapy is external beam. A typical treatment takes seven ...

  10. Imaging in radiation therapy

    Radiation therapy is an important part of cancer treatment in which cancer patients are treated using high-energy radiation such as x-rays, gamma rays, electrons, protons, and neutrons. Currently, about half of all cancer patients receive radiation treatment during their whole cancer care process. The goal of radiation therapy is to deliver the necessary radiation dose to cancer cells while minimizing dose to surrounding normal tissues. Success of radiation therapy highly relies on how accurately 1) identifies the target and 2) aim radiation beam to the target. Both tasks are strongly dependent of imaging technology and many imaging modalities have been applied for radiation therapy such as CT (Computed Tomography), MRI (Magnetic Resonant Image), and PET (Positron Emission Tomography). Recently, many researchers have given significant amount of effort to develop and improve imaging techniques for radiation therapy to enhance the overall quality of patient care. For example, advances in medical imaging technology have initiated the development of the state of the art radiation therapy techniques such as Intensity Modulated Radiation Therapy (IMRT), gated radiation therapy, tomotherapy, and Image Guided Radiation Therapy (IGRT). Capability of determining the local tumor volume and location of the tumor has been significantly improved by applying single or multi-modality imaging for static or dynamic target. The use of multi-modality imaging provides a more reliable tumor volume, eventually leading to a better definitive local control. Image registration technique is essential to fuse two different image modalities and has been in significant improvement. Imaging equipment and their common applications that are in active use and/or under development in radiation therapy are reviewed

  11. External Radiation Therapy

    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. ...

  12. External Radiation Therapy

    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 ...

  13. Radiation therapy dosimetry system

    New therapeutic treatments generally aim to increase therapeutic efficacy while minimizing toxicity. Many aspects of radiation dosimetry have been studied and developed particularly in the field of external radiation. The success of radiotherapy relies on monitoring the dose of radiation to which the tumor and the adjacent tissues are exposed. Radiotherapy techniques have evolved through a rapid transition from conventional three-dimensional (3D) conformal radiation therapy to intensity-modulated radiation therapy (IMRT) treatments or radiosurgery and robotic radiation therapy. These advances push the frontiers in our effort to provide better patient care by improving the precision of the absorbed dose delivered. This paper presents state-of-the art radiation therapy dosimetry techniques as well as the value of integral dosimetry (INDOS), which shows promise in the fulfillment of radiation therapy dosimetry requirements. - highlights: • Pre-treatment delivery and phantom dosimetry in brachytherapy treatments were analyzed. • Dose distribution in the head and neck was estimated by physical and mathematical dosimetry. • Electron beam flattening was acquired by means of mathematical, physical and “in vivo” dosimetry. • Integral dosimetry (INDOS) has been suggested as a routine dosimetric method in all radiation therapy treatments

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

    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.

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

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

  16. Radiation therapy physics

    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

  17. An automatic CT-guided adaptive radiation therapy technique by online modification of multileaf collimator leaf positions for prostate cancer

    Purpose: To propose and evaluate online adaptive radiation therapy (ART) using in-room computed tomography (CT) imaging that detects changes in the target position and shape of the prostate and seminal vesicles (SVs) and then automatically modifies the multileaf collimator (MLC) leaf pairs in a slice-by-slice fashion. Methods and materials: For intensity-modulated radiation therapy (IMRT) using a coplanar beam arrangement, each MLC leaf pair projects onto a specific anatomic slice. The proposed strategy assumes that shape deformation is a function of only the superior-inferior (SI) position. That is, there is no shape change within a CT slice, but each slice can be displaced in the anteroposterior (AP) or right-left (RL) direction relative to adjacent slices. First, global shifts (in SI, AP, and RL directions) were calculated by three-dimensional (3D) registration of the bulk of the prostate in the treatment planning CT images with the daily CT images taken immediately before treatment. Local shifts in the AP direction were then found using slice-by-slice registration, in which the CT slices were individually registered. The translational shift within a slice could then be projected to a translational shift in the position of the corresponding MLC leaf pair for each treatment segment for each gantry angle. Global shifts in the SI direction were accounted for by moving the open portal superiorly or inferiorly by an integral number of leaf pairs. The proposed slice-by-slice registration technique was tested by using daily CT images from 46 CT image sets (23 each from 2 patients) taken before the standard delivery of IMRT for prostate cancer. A dosimetric evaluation was carried out by using an 8-field IMRT plan. Results: The shifts and shape change of the prostate and SVs could be separated into 3D global shifts in the RL, AP, and SI directions, plus local shifts in the AP direction, which were different for each CT slice. The MLC leaf positions were successfully

  18. Radiation Therapy (For Parents)

    ... 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 ...

  19. External Radiation Therapy

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

  20. External Radiation Therapy

    Full Text Available ... given from an x-ray machine, and there's a variety called interstitial implantation, which uses radioactive seeds. ... common form of radiation therapy is external beam. A typical treatment takes seven weeks. Gunnar Zagars, M. ...

  1. Image-guided adaptive radiation therapy (IGART): Radiobiological and dose escalation considerations for localized carcinoma of the prostate

    The goal of this work was to evaluate the efficacy of various image-guided adaptive radiation therapy (IGART) techniques to deliver and escalate dose to the prostate in the presence of geometric uncertainties. Five prostate patients with 15-16 treatment CT studies each were retrospectively analyzed. All patients were planned with an 18 MV, six-field conformal technique with a 10 mm margin size and an initial prescription of 70 Gy in 35 fractions. The adaptive strategy employed in this work for patient-specific dose escalation was to increase the prescription dose in 2 Gy-per-fraction increments until the rectum normal tissue complication probability (NTCP) reached a level equal to that of the nominal plan NTCP (i.e., iso-NTCP dose escalation). The various target localization techniques simulated were: (1) daily laser-guided alignment to skin tattoo marks that represents treatment without image-guidance, (2) alignment to bony landmarks with daily portal images, and (3) alignment to the clinical target volume (CTV) with daily CT images. Techniques (1) and (3) were resimulated with a reduced margin size of 5 mm to investigate further dose escalation. When delivering the original clinical prescription dose of 70 Gy in 35 fractions, the 'CTV registration' technique yielded the highest tumor control probability (TCP) most frequently, followed by the 'bone registration' and 'tattoo registration' techniques. However, the differences in TCP among the three techniques were minor when the margin size was 10 mm (≤1.1%). Reducing the margin size to 5 mm significantly degraded the TCP values of the 'tattoo registration' technique in two of the five patients, where a large difference was found compared to the other techniques (≤11.8%). The 'CTV registration' technique, however, did maintain similar TCP values compared to their 10 mm margin counterpart. In terms of normal tissue sparing, the technique producing the lowest NTCP varied from patient to patient. Reducing the

  2. Radiation therapy imaging apparatus

    This patent describes a radiation therapy imaging apparatus for providing images in a patient being treated on a radiation therapy apparatus for verification and monitoring of patient positioning and verification of alignment and shaping of the radiation field of the radiation therapy apparatus. It comprises: a high-energy treatment head for applying a radiation dose to a patient positioned on a treatment table, and a gantry rotatable about an isocentric axis and carrying the treatment head for permitting the radiation dose to be applied to the patient from any of a range of angles about the isocentric axis; the radiation therapy imaging apparatus including a radiation therapy image detector which comprises a video camera mounted on the gantry diametrically opposite the treat head, an elongated light-excluding enclosure enveloping the camera to exclude ambient light from the camera, a fluoroscopic plate positioned on a distal end of the enclosure remote from the camera and aligned with the head to produce a fluoroscopic image in response to radiation applied from the head through the patient, mirror means in the enclosure and oriented for reflecting the image to the camera to permit monitoring on a viewing screen of the position of the radiation field in respect to the patient, and means for retracting at least the distal end of the enclosure from a position in which the fluoroscopic plate is disposed opposite the treatment head without disturbing the position of the camera on the gantry, so that the enclosure can be collapsed and kept from projecting under the treatment table when the patient is being positioned on the treatment table

  3. Radiation therapy physics

    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.

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

    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. Involved Node Radiation Therapy

    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 ...

  6. External Radiation Therapy

    Full Text Available ... predict when or even if the remaining cancer cells will become active again. Christopher Wood, M.D.: It's at the ten-year mark where the differences between success rates with radical prostatectomy and radiation therapy become evident,and if you're not going ...

  7. Principles of radiation therapy

    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

  8. External Radiation Therapy

    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, ...

  9. Microbeam radiation therapy

    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.

  10. Principles of radiation therapy

    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

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

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

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

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

    2013-11-15

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

  13. [Problems after radiation therapy].

    Karasawa, Kumiko

    2014-01-01

    The rate of severe late adverse effects has decreased with the highly accurate administration of radiation therapy; however, the total number of patients who suffer from late effects has not decreased because of the increased total number of patients and better survival rates. Late adverse effects, occurring more than a few months after irradiation, include the extension and collapse of capillaries, thickening of the basement membrane, and scarring of tissue due to loss of peripheral vessels. The main causes of these late effects are the loss of stromal cells and vascular injury. This is in contrast to early reactions, which occur mainly due to the reorganization of slow-growing non-stem cell renewal systems such as the lung, kidney, heart, and central nervous system. In addition, the patient's quality of life is impaired if acute reactions such as mouth or skin dryness are not alleviated. Most adverse effects are radiation dose dependent, and the thresholds differ according to the radiosensitivity of each organ. These reactions occur with a latency period of a few months to more than 10 years. Understanding the clinical and pathological status, through discussion with radiation oncologists, is the essential first step. Some of the late effects have no effective treatment, but others can be treated by steroids or hyperbaric oxygen therapy. An appropriate decision is important. PMID:24423950

  14. Intracoronary radiation therapy

    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.

  15. Radiation Therapy for Skin Cancer

    ... 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 ...

  16. About radiation therapy

    Explained are the history and outline of technology in radiation therapy (RT), characteristics of dose distribution of major radiations in RT and significance of biological effective dose (BED) from aspects of radiation oncology and therapeutic prediction. The history is described from the first X-ray RT documented in 1896 to the latest (1994) RT with National Institute of Radiological Sciences (NIRS) carbon beam for tumors in trunk. X-ray RT has aimed to make the energy high because target tumors are generally present deep in the body and an ideal RT, the intensity modulated RT, has been developed to assure the desirable dose distribution (or, dose-volume histogram) based on precise planning with X-CT and computing. Low energy gamma ray emitted from radioisotopes provides also an ideal RT mean because of its excellent focusing to the internal target; however, problems remain of invasion and long lodging of the isotope in the body. Heavy ion RT is conducted on the planning on X-CT image and computation utilizing Bragg's principle and is superior for minimizing the exposure of normal, non-cancerous tissues. Boron neutron capture therapy is a promising RT as the local control is always possible at 10B ratio of the lesion/normal tissue >2.5, which is measurable by PET with 18F-boronophenylalanine. In the current oncology, BED is estimated by the linear quadratic model, α(nd)+β(nd)2, where d is a total irradiation dose and n, number of fractionation, and is a planning basis for the effect prediction in RT above. Physical problems in future involve the system development of more efficient dose focusing and convenient dose impartation, and development of more easily operable system and cost reduction is awaited. (R.T.)

  17. Radiation Therapy for Breast Cancer

    ... therapy. Ask your doctor for more information. For women undergoing reconstruction, post- mastectomy radiation may affect your options for reconstruction or the cosmetic outcome. Discuss with your surgeon and radiation oncologist ...

  18. Stereotactic body radiation therapy

    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.

  19. Stereotactic body radiation therapy

    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.

  20. The physics of radiation therapy

    Khan, Faiz M

    2009-01-01

    Dr. Khan's classic textbook on radiation oncology physics is now in its thoroughly revised and updated Fourth Edition. It provides the entire radiation therapy team—radiation oncologists, medical physicists, dosimetrists, and radiation therapists—with a thorough understanding of the physics and practical clinical applications of advanced radiation therapy technologies, including 3D-CRT, stereotactic radiotherapy, HDR, IMRT, IGRT, and proton beam therapy. These technologies are discussed along with the physical concepts underlying treatment planning, treatment delivery, and dosimetry. This Fourth Edition includes brand-new chapters on image-guided radiation therapy (IGRT) and proton beam therapy. Other chapters have been revised to incorporate the most recent developments in the field. This edition also features more than 100 full-color illustrations throughout.

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

    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

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

    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

  3. Radiation therapy in palliative care

    Radiation therapy is a valuable treatment for palliation of local symptoms with consistently high response rates in the relief and control of bone pain, neurological symptom, obstructive symptoms, and tumor hemorrhage. Over than 80% of patients who developed bone metastasis and superior vena cava syndrome obtained symptom relief by radiation therapy. Radiation therapy is also well established as an effective treatment for brain metastasis, improving symptoms and preventing progressive neurological deficits, and recently stereotactic irradiation had became a alternative treatment of surgery for small metastatic brain tumors. Both radiation therapy and surgery are effective in the initial treatment of malignant spinal cord compression syndrome, and no advantages of surgery over radiation therapy has been demonstrated in published series when patients have a previously conformed diagnosis of malignant disease and no evidence of vertebral collapse. The outcome of treatment depends primarily upon the speed of diagnosis and neurological status at initiation of treatment. It is very important to start radiation therapy before patient become non-ambulant. Low irradiation dose and short treatment period of palliative radiation therapy can minimize disruption and acute morbidity for the patients with advanced cancer with enabling control of symptoms and palliative radiation therapy is applicable to the patient even in poor general condition. (author)

  4. Design of adaptive treatment margins for non-negligible measurement uncertainty: application to ultrasound-guided prostate radiation therapy

    Daily imaging during the course of a fractionated radiotherapy treatment has the potential for frequent intervention and therefore effective adaptation of the treatment to the individual patient. The treatment information gained from such images can be analysed and updated daily to obtain a set of patient individualized parameters. However, in many situations, the uncertainty with which these parameters are estimated cannot be neglected. In this work this methodology is applied to the adaptive estimation of setup errors, the derivation of a daily optimal pre-treatment correction strategy, and the daily update of the treatment margins after application of these corrections. For this purpose a dataset of 19 prostate cancer patients was analysed retrospectively. The position of the prostate was measured daily with an optically guided 3D ultrasound localization system. The measurement uncertainty of this system is approximately 2 mm. The algorithm finds the most likely position of the target maximizing an a posteriori probability given the set of measurements. These estimates are used for the optimal corrections applied to the target volume. The results show that the application of the optimal correction strategy allows a reduction in the treatment margins in a systematic way with increasing progression of the treatment. This is not the case using corrections based only on the measured values that do not take the measurement uncertainty into account

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

    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

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

    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

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

    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

  8. Risk-adapted partial larynx and/or carotid artery sparing modulated radiation therapy of glottic cancer

    To evaluate outcome in patients with glottic cancer treated with intensity-modulated radiotherapy (IMRT) and to show effectiveness of partial laryngeal- and/or carotid artery sparing in low to intermediate risk tumors. Retrospective analysis. From 01/2004 to 03/2013 77 consecutive patients presenting with glottic cancer were treated in our department with IMRT as definitive treatment. T-stages distributed as follows: T1: n = 17, T2: n = 24, T3: n = 15, T4: n = 13 and recurrences: 8 patients. Concomitant systemic therapy was applied in 39 patients consisting of either cisplatin or cetuximab. Mean/median follow-up (FU) time was 32.2/28 months (range: 4–98.7). Three year local control (LC), ultimate LRC and laryngectomy free survival rate was 77%, 92% and 80%, respectively. Three year overall survival of the entire cohort was 81%. Three year local control for T1/T2, T3/T4, and recurred tumors was 95%, 65%, and 38%, respectively. Three year overall survival was 86% for T1-4 stages, 55% for recurred disease, respectively. Partial laryngeal/carotid artery sparing was performed in all T1 patients (n = 17) and 17/22 T2N0 patients. Rate of late sequels was low. IMRT for glottic cancer shows high control rates. In low to intermediate risk tumors an individualized treatment volume with partial larynx +/- carotid artery sparing is effective and holds the potential to reduce long term toxicity. The therapeutic outcome was not compromised

  9. Comparison of 12 deformable registration strategies in adaptive radiation therapy for the treatment of head and neck tumors

    Background and purpose: Weight loss, tumor shrinkage, and tissue edema induce substantial modification of patient's anatomy during head and neck (HN) radiotherapy (RT) or chemo-radiotherapy. These modifications may impact on the dose distribution to both target volumes (TVs) and organs at risk (OARs). Adaptive radiotherapy (ART) where patients are re-imaged and re-planned several times during the treatment is a possible strategy to improve treatment delivery. It however requires the use of specific deformable registration (DR) algorithms that requires proper validation on a clinical material. Materials and methods: Twelve voxel-based DR strategies were compared with a dataset of 5 patients imaged with computed tomography (CT) before and once during RT (on average after a mean dose of 36.8 Gy): level-set (LS), level-set implemented in multi-resolution (LSMR), Demons' algorithm implemented in multi-resolution (DMR), DMR followed by LS (DMR-LS), fast free-form deformable registration via calculus of variations (F3CV) and F3CV followed by LS (F3CV-LS). The use of an edge-preserving denoising filter called 'local M-smoothers' applied to the registered images and combined to all the aforesaid strategies was also tested (fLS, fLSMR, fDMR, fDMR-LS, fF3CV, fF3CV-LS). All these strategies were compared to a rigid registration based on mutual information (MI, fMI). Chronological and anti-chronological registrations were also studied. The various DR strategies were evaluated using a volume-based criterion (i.e. Dice similarity index, DSI) and a voxel-intensity criterion (i.e. correlation coefficient, CC) on a total of 18 different manually contoured volumes. Results: For the DSI analysis, the best three strategies were DMR, fDMR-LS, and fDMR, with the median values of 0.86, 0.85 and 0.85, respectively; corresponding inter-quartile range (IQR) reached 9.6%, 10% and 10.2%. For the CC analysis, the best three strategies were fDMR-LS, DMR-LS and DMR with the median values of 0

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

    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

  11. 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?

    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

  12. External Radiation Therapy

    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 ...

  13. Radiation safety consideration during intraoperative radiation therapy

    Using in-house-designed phantoms, the authors evaluated radiation exposure rates in the vicinity of a newly acquired intraoperative radiation therapy (IORT) system: Axxent Electronic Brachytherapy System. The authors also investigated the perimeter radiation levels during three different clinical intraoperative treatments (breast, floor of the mouth and bilateral neck cancer patients). Radiation surveys during treatment delivery indicated that IORT using the surface applicator and IORT using balloons inserted into patient body give rise to exposure rates of 200 mR h-1, 30 cm from a treated area. To reduce the exposure levels, movable lead shields should be used as they reduce the exposure rates by >95 %. The authors' measurements suggest that intraoperative treatment using the 50-kVp X-ray source can be administered in any regular operating room without the need for radiation shielding modification as long as the operators utilise lead aprons and/or stand behind lead shields. (authors)

  14. External Radiation Therapy

    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 ...

  15. Rectal injuries following radiation therapy

    Rectal injuries following radiation therapy were reviewed. Primary diseases in which radiation injuries appeared were described, and local injuries in the neibouring organs such as the small intestine, the bladder, the uterus, and the vagina were also referred to. Classification, frequency, fistulation, radiation necrosis, x-ray findings and occurrence time of rectal and sigmoid colonic injuries were reported. As occurrence factors of radiation injuries, total dose, measurement of dose, stage of primary disease, and history of laparatomy were mentioned. Countermeasures for reducing rectal injuries and treatment methods of local injuries were also described. (Serizawa, K.)

  16. Radiation Therapy of Pituitary Tumors

    Radiation treatment results were analyzed in a retrospective analysis of 47 patients with pituitary adenoma treated with radiation alone or combined with surgery from 1974 through 1987 at the Department of Therapeutic Radiology of Kyung Hee University. The 5-year overall survival rates for all patients was 80.4%. Radiation therapy was effective for improving visual symptoms and headache, but could not normalize amenorrhea and galactorrhoea. There was no difference of survival rate between radiation alone and combination with surgery. Prognostic factors such as age, sex, disease type, visual field, headache and surgical treatment were statistically no significant in survival rates of these patients

  17. FDG-PET response-adapted therapy

    Hutchings, Martin

    2014-01-01

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

  18. 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

    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

  19. Evaluation of 4-dimensional Computed Tomography to 4-dimensional Cone-Beam Computed Tomography Deformable Image Registration for Lung Cancer Adaptive Radiation Therapy

    Purpose: To evaluate 2 deformable image registration (DIR) algorithms for the purpose of contour mapping to support image-guided adaptive radiation therapy with 4-dimensional cone-beam CT (4DCBCT). Methods and Materials: One planning 4D fan-beam CT (4DFBCT) and 7 weekly 4DCBCT scans were acquired for 10 locally advanced non-small cell lung cancer patients. The gross tumor volume was delineated by a physician in all 4D images. End-of-inspiration phase planning 4DFBCT was registered to the corresponding phase in weekly 4DCBCT images for day-to-day registrations. For phase-to-phase registration, the end-of-inspiration phase from each 4D image was registered to the end-of-expiration phase. Two DIR algorithms—small deformation inverse consistent linear elastic (SICLE) and Insight Toolkit diffeomorphic demons (DEMONS)—were evaluated. Physician-delineated contours were compared with the warped contours by using the Dice similarity coefficient (DSC), average symmetric distance, and false-positive and false-negative indices. The DIR results are compared with rigid registration of tumor. Results: For day-to-day registrations, the mean DSC was 0.75 ± 0.09 with SICLE, 0.70 ± 0.12 with DEMONS, 0.66 ± 0.12 with rigid-tumor registration, and 0.60 ± 0.14 with rigid-bone registration. Results were comparable to intraobserver variability calculated from phase-to-phase registrations as well as measured interobserver variation for 1 patient. SICLE and DEMONS, when compared with rigid-bone (4.1 mm) and rigid-tumor (3.6 mm) registration, respectively reduced the average symmetric distance to 2.6 and 3.3 mm. On average, SICLE and DEMONS increased the DSC to 0.80 and 0.79, respectively, compared with rigid-tumor (0.78) registrations for 4DCBCT phase-to-phase registrations. Conclusions: Deformable image registration achieved comparable accuracy to reported interobserver delineation variability and higher accuracy than rigid-tumor registration. Deformable image registration

  20. External Radiation Therapy

    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. ...

  1. Radiation Therapy for Cancer

    ... 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 ...

  2. Intensity-modulated radiation therapy.

    Goffman, Thomas E; Glatstein, Eli

    2002-07-01

    Intensity-modulated radiation therapy (IMRT) is an increasingly popular technical means of tightly focusing the radiation dose around a cancer. As with stereotactic radiotherapy, IMRT uses multiple fields and angles to converge on the target. The potential for total dose escalation and for escalation of daily fraction size to the gross cancer is exciting. The excitement, however, has greatly overshadowed a range of radiobiological and clinical concerns. PMID:12071811

  3. Khan's the physics of radiation therapy

    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 (

  4. Radiation therapy for endometrial carcinoma

    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

  5. Radiation therapy for retinoblastoma

    Treatment results were examined about 39 retinoblastoma introduced to the radiotherapy purpose, at National Center for Child Health and Development, during the 37 years from 1975 to 2012. In 29 patients of bilateral, 24 patients were postoperative radiotherapy, 4 patients were for preservation purpose. In 10 unilateral patients, 5 patients were postoperative, 4 patients were for preservation purpose. Delayed adverse events, 11 patients with cataracts requiring surgery, pituitary dysfunction 2 patients who take a hormone replacement, 1 glaucoma, were showed. The recurrence was 6 patients, and inner 1 patient was a trilateral retinoblastoma, and turned into the only death case. The onset of secondary cancer was observed in 4 patients, 1 was Merkel cell carcinoma and 3 patients were rhabdomyosarcoma. All had occurred out of the radiation field. (author)

  6. Anaemia and radiation therapy

    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)

  7. Radiation Therapy: Preventing and Managing Side Effects

    ... 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 ...

  8. Radiation therapy of esophageal cancer

    Radiation therapy has been used extensively in the management of patients with cancer of the esophagus. It has demonstrated an ability to cure a small minority of patients. Cure is likely to be limited to patients who have lesions less than 5 cm in length and have minimal, if any, involvement of lymph nodes. Esophagectomy is likely to cure a similar, small percentage of patients with the same presentation of minimal disease but has a substantial acute postoperative mortality rate and greater morbidity than irradiation. Combining surgery and either preoperative or postoperative irradiation may cure a small percentage of patients beyond the number cured with either modality alone. Radiation has demonstrated benefit as an adjuvant to surgery following the resection of minimal disease. However, radiation alone has never been compared directly with surgery for the highly select, minimal lesions managed by surgery. Radiation provides good palliation of dysphagia in the majority of patients, and roughly one third may have adequate swallowing for the duration of their illness when ''radical'' doses have been employed. Surgical bypass procedures have greater acute morbidity but appear to provide more reliable, prolonged palliation of dysphagia. Several approaches to improving the efficacy of irradiation are currently under investigation. These approahces include fractionation schedules, radiosensitizers, neutron-beam therapy, and helium-ion therapy

  9. Fractionated radiation therapy after Strandqvist

    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.)

  10. Oray surgery and radiation therapy

    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.

  11. Radiation Therapy and Hearing Loss

    A review of literature on the development of sensorineural hearing loss after high-dose radiation therapy for head-and-neck tumors and stereotactic radiosurgery or fractionated stereotactic radiotherapy for the treatment of vestibular schwannoma is presented. Because of the small volume of the cochlea a dose-volume analysis is not feasible. Instead, the current literature on the effect of the mean dose received by the cochlea and other treatment- and patient-related factors on outcome are evaluated. Based on the data, a specific threshold dose to cochlea for sensorineural hearing loss cannot be determined; therefore, dose-prescription limits are suggested. A standard for evaluating radiation therapy-associated ototoxicity as well as a detailed approach for scoring toxicity is presented.

  12. [Radiation therapy of pancreatic cancer].

    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

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

    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.

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

    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.

  15. Radiation therapy for pleural mesothelioma

    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

  16. Development of local radiation therapy

    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

  17. Development of local radiation therapy

    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.

  18. Late complications of radiation therapy

    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)

  19. Practical risk management in radiation therapy

    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)

  20. Radiation therapy of suprasellar germinomas

    From 1974 to 1984, nine patients with suprasellar germinoma were treated with megavoltage radiation therapy. The entire craniospinal axis was irradiated in all patients, with median doses of 45 Gy, 44.4 Gy, and 24 Gy delivered to the tumor volume, whole brain, and spinal cord, respectively. There have been no tumor recurrences, with median 56-month follow-up among seven survivors. Two patients have died (12, 14 months) without evidence of tumor, both of uncontrolled endocrine dysfunction. The dose usually recommended for treatment of intracranial germinoma is 50-55 Gy. The data suggest that 45 Gy may be sufficient

  1. Radiation therapy in bronchogenic carcinoma

    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

  2. Insufficiency fracture after radiation therapy

    Insufficiency fracture occurs when normal or physiological stress applied to weakened bone with demineralization and decreased elastic resistance. Recently, many studies reported the development of IF after radiation therapy (RT) in gynecological cancer, prostate cancer, anal cancer and rectal cancer. The RT-induced insufficiency fracture is a common complication during the follow-up using modern imaging studies. The clinical suspicion and knowledge the characteristic imaging patterns of insufficiency fracture is essential to differentiate it from metastatic bone lesions, because it sometimes cause severe pain, and it may be confused with bone metastasis.

  3. Evaluation on lung cancer patients' adaptive planning of TomoTherapy utilising radiobiological measures and Planned Adaptive module.

    Su, Fan-Chi; Shi, Chengyu; Mavroidis, Panayiotis; Rassiah-Szegedi, Prema; Papanikolaou, Niko

    2009-01-01

    Adaptive radiation therapy is a promising concept that allows individualised, dynamic treatment planning based on feedback of measurements. The TomoTherapy Planned Adaptive application, integrated to the helical TomoTherapy planning system, enables calculation of actual dose delivered to the patient for each treatment fraction according to the pretreatment megavoltage computed tomography (MVCT) scan and image registration. As a result, new fractionation treatment plans are available if correction is necessary. In order to evaluate therealclinicaleffect,biologicaldoseis preferred to physical dose. A biological parameter, biologically effective uniform dose ([Formula: see text]), has the advantages of not only reporting delivered dose but also facilitating the analysis of dose-response relations, which link radiation dose to the clinical effect. Therefore, in this study, four lung patients' adaptive plans were evaluated using the [Formula: see text] in addition to physical doses estimated from the TomoTherapy Planned Adaptive module. Higher complication-free tumour control probability (P(+))(of about 8%) was observed in patients treated with larger dose-per-fraction by using the [Formula: see text] in addition to the physical dose. Moreover, a significant increase of 13.2% in the P(+) for the adaptive TomoTherapy plan in one of the lung cancer patients was also observed, which indicates the clinical benefit of adaptive TomoTherapy. PMID:20376282

  4. Risk analysis of external radiation therapy

    External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy

  5. 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

    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.

  6. Cancer Treatment with Gene Therapy and Radiation Therapy

    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...

  7. Melioidosis: reactivation during radiation therapy

    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

  8. Melioidosis: reactivation during radiation therapy

    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.

  9. Adaptive responses to antibody based therapy.

    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

  10. Radiation therapy facilities in the United States

    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

  11. Radiation Therapy for Early Stage Lung Cancer

    Parashar, Bhupesh; Arora, Shruthi; Wernicke, A. Gabriella

    2013-01-01

    Radiation therapy for early stage lung cancer is a promising modality. It has been traditionally used in patients not considered candidates for standard surgical resection. However, its role has been changing rapidly since the introduction of new and advanced technology, especially in tumor tracking, image guidance, and radiation delivery. Stereotactic radiation therapy is one such advancement that has shown excellent local control rates and promising survival in early stage lung cancer. In a...

  12. Epigenomic Adaptation to Low Dose Radiation

    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.’

  13. Radiation therapy of CNS lymphoma

    A retrospective analysis of 22 patients with central nervous system (CNS) non-Hodgkin's lymphomas seen from 1978 to 1989 at Hamamatsu University Hospital was carried out. These were corresponding to 16% (22/137) of non-Hodgkin's lymphomas treated by irradiation during the same period. Six patients had primary intracranial involvement, six had secondary one, five had leptomeningeal involvement and five had spinal cord compression. Median survival of these groups 29 months, 7 months, 6 months and 4 months, respectively. On the case primary intracranial involvement, neurological signs and symptoms and performance status (PS) were improved in most patients. Whole brain irradiation with a dose of 45 Gy to 50 Gy followed by systemic chemotherapy was considered as effective treatment modalities. On the other hand, for the secondary intracranial lymphomas, clinical symptoms and PS were excellently improved by radiation therapy; however, these did not reflect survival. The conditions having primary site on gastrointestinal tract and relapse as systemic dissemination were considerable risk factors for the control of CNS involvement. For these patients, prophylactic chemotherapy is necessary. Improvement of PS on patients with leptomeningeal lymphomas was obtained in only 3 of 5 cases. These were treated by irradiation on whole spine or neuroaxis and intrathecal MTX injection. We observed 2 cases dying from cerebrovascular accident and one case from leukoencephalopathy. This showed that such combination therapy should be carefully attempted. Five patients having spinal cord compression suffered from paraplegia and none of them had been improved on their symptoms. Four of 5 patients complained of back pain one to two months before onset of paraplegia without abnormal findings on spine roentgenograms. Therefore, studies with myelography or MRI are considered to be essential to patients with non-Hodgkin's lymphoma who complained of back pain. (author)

  14. Radiation Therapy for Gynecologic Cancers

    ... the doctors who oversee the care of each person undergoing radiation treatment. Other members of the treatment team include radiation therapists, radiation oncology nurses, medical physicists, dosimetrists, social workers ...

  15. Study on external beam radiation therapy

    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.

  16. Study on external beam radiation therapy

    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

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

    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

  18. Radiation therapy for renal transplant rejection reactions

    Forty-four renal transplant patients were given radiation therapy for severe rejection phenomena. The 29 patients who had only one course of irradiation had a 52.3% successful function rate. Fifteen patients received from two to four courses of irradiation with an ultimate 60% rate of sustained function. Fifty patients who received only steroid and other medical management but no irradiation had a 60% rate of successful renal function. In the irradiation group, no patient whose creatinine level did not respond to radiation therapy maintained a functioning kidney. The data indicate that the overall successful function rate is maintained by radiation therapy in patients who show severe allograft rejection phenomena

  19. Radiation therapy for renal transplant rejection reactions

    Peeples, W.J.; Wombolt, D.G.; El-Mahdi, A.M.; Turalba, C.I.

    1982-01-01

    Forty-four renal transplant patients were given radiation therapy for severe rejection phenomena. The 29 patients who had only one course of irradiation had a 52.3% successful function rate. Fifteen patients received from two to four courses of irradiation with an ultimate 60% rate of sustained function. Fifty patients who received only steroid and other medical management but no irradiation had a 60% rate of successful renal function. In the irradiation group, no patient whose creatinine level did not respond to radiation therapy maintained a functioning kidney. The data indicate that the overall successful function rate is maintained by radiation therapy in patients who show severe allograft rejection phenomena.

  20. Modern radiation therapy for extranodal lymphomas

    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...... adopted RT volume definitions based on the International Commission on Radiation Units and Measurements (ICRU), as has been widely adopted by the field of radiation oncology for solid tumors. Organ-specific recommendations take into account histological subtype, anatomy, the treatment intent, and other...

  1. Detoxication and antiproteolytic therapy of radiation complications

    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.

  2. 42 CFR 410.35 - X-ray therapy and other radiation therapy services: Scope.

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false X-ray therapy and other radiation therapy services... Other Health Services § 410.35 X-ray therapy and other radiation therapy services: Scope. Medicare Part B pays for X-ray therapy and other radiation therapy services, including radium therapy...

  3. Managing the adverse effects of radiation therapy.

    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

  4. Hyperbaric oxygen therapy for radiation myelitis

    Radiation therapy may damage healthy tissues adjacent to tumor. Hyperbaric oxygen therapy (HBO) is useful in treating soft tissue and osteoradionecrosis. In addition, HBO has been recommended to treat radiation-induced myelitis. We used radiation to induce a predictable myelitis in the spinal cords of rats who were randomized into treatment (HBO) and control groups 8 wk after irradiation. Serial neurologic examination showed no benefit or harm as a result of HBO. This small pilot study did not demonstrate any clinically significant benefit of HBO for radiation myelitis in rats

  5. Radiation therapy in elderly patients

    Elderly patients, or those individuals over 65 or 70 depending on the different authors, represent the majority of cancer patients who treated with radiation therapy (RT), however there are very few publications that we provide information needed to evaluate the use of RT in the treatment elders regarding: indication of dose, tissue tolerance, toxicity and association with other therapeutic modalities. In the treatment process must take into account RT radiobiology Clinical applied to each patient and is more relevant in the elderly in which often are comorbid conditions and functional limitations normal tissues increases with age and disease coexisting vascular and connective influencing RT treatment. Chronological age does not correlate with the biological age for tolerance normal tissue, however frequently refers to healthy tissue in the elderly are less tolerant than healthy tissue RT adults young but no data in the literature to support it and perhaps those claims probably based on the presence of comorbid conditions or diseases associated or previous surgeries that influence the risk of tissue damage healthy. Studies conducted by the EORTC not show differences in toxicity acute and late age-related. Elderly patients tolerate RT like younger patients with comparable side effects. In the case of concurrent chronic diseases should take into account a possible modification of the dose and volume irradiated to prevent the risk develop permanent damage or sector body lest un irradiated able to compensate for the loss of function of the irradiated tissue; but we should always note that the dose reduction while reducing the risk of complications also decreases the chance of cure

  6. Comparing Postoperative Radiation Therapies for Brain Metastases

    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.

  7. Nursing care update: Internal radiation therapy

    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

  8. Modern radiation therapy for primary cutaneous lymphomas

    Specht, Lena; Dabaja, Bouthaina; Illidge, Tim;

    2015-01-01

    Primary cutaneous lymphomas are a heterogeneous group of diseases. They often remain localized, and they generally have a more indolent course and a better prognosis than lymphomas in other locations. They are highly radiosensitive, and radiation therapy is an important part of the treatment......, either as the sole treatment or as part of a multimodality approach. Radiation therapy of primary cutaneous lymphomas requires the use of special techniques that form the focus of these guidelines. The International Lymphoma Radiation Oncology Group has developed these guidelines after multinational...... meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the International Lymphoma Radiation Oncology Group steering committee on the use of radiation therapy in primary cutaneous lymphomas in the modern era....

  9. 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.

    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.

  10. Radiation therapy apparatus having retractable beam stopper

    This invention relates to a radiation therapy apparatus which utilized a linear translation mechanism for positioning a beam stopper. An apparatus is described wherein the beam stopper is pivotally attached to the therapy machine with an associated drive motor in such a way that the beam stopper retracts linearly

  11. Volume and dosimetric changes and initial clinical experience of a two-step adaptive intensity modulated radiation therapy (IMRT) scheme for head and neck cancer

    Purpose: The aim of this study was to show the benefit of a two-step intensity modulated radiotherapy (IMRT) method by examining geometric and dosimetric changes. Material and Methods: Twenty patients with pharyngeal cancers treated with two-step IMRT combined with chemotherapy were included. Treatment-planning CT was done twice before IMRT (CT-1) and at the third or fourth week of IMRT for boost IMRT (CT-2). Transferred plans recalculated initial plan on CT-2 were compared with the initial plans on CT-1. Dose parameters were calculated for a total dose of 70 Gy for each plan. Results: The volumes of primary tumors and parotid glands on CT-2 regressed significantly. Parotid glands shifted medially an average of 4.2 mm on CT-2. The mean doses of the parotid glands in the initial and transferred plans were 25.2 Gy and 30.5 Gy, respectively. D2 (dose to 2% of the volume) doses of the spinal cord were 37.1 Gy and 39.2 Gy per 70 Gy, respectively. Of 15 patients in whom xerostomia scores could be evaluated 1–2 years after IMRT, no patient complained of grade 2 or more xerostomia. Conclusions: This two-step IMRT method as an adaptive RT scheme could adapt to changes in body contour, target volumes and risk organs during IMRT

  12. Care of the patient receiving radiation therapy

    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

  13. Wound healing following radiation therapy: a review

    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

  14. Role of radiation therapy in gastric adenocarcinoma

    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.

  15. Evolution of radiation therapy: technology of today

    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

  16. Research Findings on Radiation Hormesis and Radon Therapy

    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

  17. Modern Radiation Therapy for Hodgkin Lymphoma

    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...... Lymphoma Radiation Oncology Group (ILROG) Steering Committee regarding the modern approach to RT in the treatment of HL, outlining a new concept of ISRT in which reduced treatment volumes are planned for the effective control of involved sites of HL. Nodal and extranodal non-Hodgkin lymphomas (NHL) are...... Commission on Radiation Units and Measurements concepts of gross tumor volume, clinical target volume, internal target volume, and planning target volume are used for defining the targeted volumes. Newer treatment techniques, including intensity modulated radiation therapy, breath-hold, image guided...

  18. Protective prostheses during radiation therapy

    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

  19. 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

    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

  20. 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

    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

  1. Impact of radiation therapy on sexual life

    The aim of this study was to evaluate the impact of radiation therapy on sexual life. The analysis was based on a Pubmed literature review. The keywords used for this research were 'sexual, radiation, oncology, and cancer'. After a brief reminder on the anatomy and physiology, we explained the main complications of radiation oncology and their impact on sexual life. Preventive measures and therapeutic possibilities were discussed. Radiation therapy entails local, systematic and psychological after-effects. For women, vaginal stenosis and dyspareunia represent the most frequent side effects. For men, radiation therapy leads to erectile disorders for 25 to 75% of the patients. These complications have an echo often mattering on the patient quality of life of and on their sexual life post-treatment reconstruction. The knowledge of the indications and the various techniques of irradiation allow reducing its potential sexual morbidity. The information and the education of patients are essential, although often neglected. In conclusion, radiation therapy impacts in variable degrees on the sexual life of the patients. Currently, there are not enough preventive and therapeutic means. Patient information and the early screening of the sexual complications are at stake in the support of patients in the reconstruction of their sexual life. (authors)

  2. Cancer and electromagnetic radiation therapy: Quo Vadis?

    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...

  3. Radiation therapy for intracranial germ cell tumors

    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.

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

    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...

  5. Dose calculation algorithms for radiation therapy with an MRI-Integrated radiation device

    Image-guided adaptive radiation therapy (IGART) aims at improving therapy outcome on the basis of more precise knowledge of the anatomical and physiological situation during treatment. By integration of magnetic resonance imaging (MRI), better differentiation is possible between the target volume to be irradiated and healthy surrounding tissues. In addition, changes that occur either between or during treatment fractions can be taken into account. On the basis of this information, a better conformation of radiation dose to the target volume may be achieved, which may in turn improve prognosis and reduce radiation side effects. This requires a precise calculation of radiation dose in a magnetic field that is present in these integrated irradiation devices. Real-time adaptation of the treatment plan is aimed at for which fast dose calculation is needed. Kernel-based methods are good candidates to achieve short calculation times; however, they presently only exist for radiation therapy in the absence of magnetic fields. This work suggests and investigates two approaches towards kernel-based dose calculation algorithms. One of them is integrated into treatment plan optimisation and applied to four clinical cases.

  6. Radiation Therapy for Pilocytic Astrocytomas of Childhood

    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.

  7. Early cardiac changes related to radiation therapy

    To investigate the incidence and severity of possible radiation-induced cardiac changes, 21 women without heart disease were investigated serially by echocardiography and by measuring systolic time intervals before and up to 6 months after postoperative radiation therapy because of breast cancer. Radiation was associated with a decrease in fractional systolic shortening of the left ventricular (LV) minor-axis diameter, from 0.35 +/- 0.05 to 0.32 +/- 0.06 (p less than 0.005), and in the systolic blood pressure/end-systolic diameter ratio, from 4.4 +/- 1.2 to 3.9 +/- 0.9 mm Hg/mm (p less than 0.005). The mitral E point-septal separation increased, from 2.8 +/- 1.5 to 4.2 +/- 2.5 mm (p less than 0.005). The preejection period/LV ejection time ratio of systolic time intervals increased, but only the decrease within 6 months after therapy was significant (p less than 0.005). All these changes reflect slight transient depression of LV function, which became normalized within 6 months after therapy. Up to 6 months after therapy, a slight pericardial effusion was found in 33% of the patients. Hence, conventional radiation therapy appeared to cause an acute transient and usually symptomless decrease in LV function, and later, slight pericardial effusion in one-third of the patients

  8. Monte Carlo techniques in radiation therapy

    Verhaegen, Frank

    2013-01-01

    Modern cancer treatment relies on Monte Carlo simulations to help radiotherapists and clinical physicists better understand and compute radiation dose from imaging devices as well as exploit four-dimensional imaging data. With Monte Carlo-based treatment planning tools now available from commercial vendors, a complete transition to Monte Carlo-based dose calculation methods in radiotherapy could likely take place in the next decade. Monte Carlo Techniques in Radiation Therapy explores the use of Monte Carlo methods for modeling various features of internal and external radiation sources, including light ion beams. The book-the first of its kind-addresses applications of the Monte Carlo particle transport simulation technique in radiation therapy, mainly focusing on external beam radiotherapy and brachytherapy. It presents the mathematical and technical aspects of the methods in particle transport simulations. The book also discusses the modeling of medical linacs and other irradiation devices; issues specific...

  9. Eosinophilia following radiation therapy Fin childhood

    Radiation related eosinophilia (R.R.E.) has been observed mainly among the patients who received radiation therapy for uterine cancer, which was said to Fbe the sign of good prognosis. Retrospective study of eosinophilia following radiation therapy was performed in 41 pediatric patients with acute lymphoblastic leukemia, brain tumor and so on. Thirty-two per cent of all courses of radiation therapy was associated with R.R.E.. Eosinophil counts increased gradually from two weeks after the start of therapy and reached to maximun on the 33rd day (mean). R.R.E. was seen much more frequently among the patients with brain tumor than those with ALL. And R.R.E. was also related to radiation dose. Patients under 3 years of age showed R.R.E. less frequently comparing to the older age group. Those findings might mean that R.R.E. was strongly related to the host's immunological function. This is the first report about R.R.E. in childhood. (author)

  10. Bullous pemphigoid after radiation therapy

    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

  11. Malignant peritoneal mesothelioma after radiation therapy

    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.)

  12. Cancer and electromagnetic radiation therapy: Quo Vadis?

    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...

  13. 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

    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.)

  14. Effects of radiation therapy in microvascular anastomoses

    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.

  15. Effects of radiation therapy in microvascular anastomoses

    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

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

    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)

  17. Adapting Metacognitive Therapy to Children with Generalised Anxiety Disorder

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

    2015-01-01

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

  18. Radiation Therapy of Maxillary Sinus Cancer

    Purpose: Maxillary sinus cancers usually are locally advanced and involve the structures around sinus. It is uncommon for this cancer to spread to the regional lymphnodes. For this reason, local control is of paramount important for cure. A policy of combined treatment is generally accepted as the most effective means of enhancing cure rates. This paper reports our experience of a retrospective study of 31 patients treated with radiation therapy alone and combination therapy of surgery and radiation. Materials and Methods: Between July 1974 and January 1992, 47 patients with maxillary sinus cancers underwent either radiation therapy alone or combination therapy of surgery and radiation. Of these, only 31 patients were eligible for analysis. The distribution of clinical stage by the AJCC system was 26%(8/31) for T2 and 74%(23/31) for T3 and T4. Eight patients had palpable lymphadenopathy at diagnosis. Primary site was treated by Cobalt-60 radiation therapy using through a 45 .deg. wedge-pair technique. Elective neck irradiation was not routinely given. Of these 8 patients, the six who had clinically involved nodes were treated with definite radiation therapy. The other two patients had received radical neck dissection. The twenty-two patients were treated with radiation alone and 9 patients were treated with combination radiation therapy. The RT alone patients with RT dose less than 60 Gy were 9 and those above 60 Gy were 13. Results: The overall 5 year survival rate was 23.8%. The 5 year survival rate by T-stage was 60.5% and 7.9% for T2 and T3, 4 respectively. Statistical significance was found by T-stage (p30.1). The 5 year survival rate for RT alone and combination RT was 22.5% and 27.4%, respectively. The primary local control rate was 65%(20/31). Conclusion: This study did not show significant difference in survival between RT alone and combination RT. There is still much controversy with regard to which treatment is optimum. Improved RT technique and

  19. Transitioning from 2-D Radiation Therapy to 3-D Conformal Radiation Therapy and Intensity Modulated Radiation Therapy: Training Material

    The technology of radiation oncology has advanced very rapidly in recent years. However, the sophistication of technology available in individual radiation therapy centres varies dramatically throughout the world. Treatment capabilities with planar imaging and limited cross-sectional imaging support have been labelled as two dimensional radiation therapy (2-D RT). With increased use of more advanced cross-sectional imaging, the introduction of more complex dose calculation capabilities for treatment planning and more sophisticated treatment delivery procedures, three dimensional conformal radiation therapy (3-D CRT) can be provided. Further sophistication in treatment planning and treatment delivery capabilities enables intensity modulated radiation therapy (IMRT). Recognizing that huge disparities exist across the world, and in an attempt to aid in advancing institutional capabilities, the IAEA published ‘Transition from 2-D Radiotherapy to 3-D Conformal and Intensity Modulated Radiotherapy’ (IAEA-TECDOC-1588) in May 2008. Divided into two parts — on CRT and on IMRT — the publication provides guidelines on the transition from 2-D RT through 3-D CRT to IMRT. It is recognized that 3-D CRT is the standard of care in most radiation treatment processes and that IMRT technologies are still evolving. The publication provides clear guidelines and highlights the milestones to be achieved when transitioning from 2-D RT to 3-D CRT and IMRT. While IAEA-TECDOC-1588 provides comprehensive guidelines and milestones, the present publication provides training materials to aid professionals in the continuing education required for the implementation of more advanced treatment capabilities, especially 3-D CRT. These materials are based on the results of two consultants meetings organized by the IAEA in 2009 and 2010, primarily focused on providing guidance on what training materials were available or needed to be developed, with a special emphasis on transitioning from 2-D

  20. Electron beams in radiation therapy

    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.)

  1. Delineating organs at risk in radiation therapy

    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

  2. Process of Coping with Radiation Therapy.

    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…

  3. Radiation therapy of cancer of the lung

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

  4. Computer models for optimizing radiation therapy

    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.)

  5. Combined therapy of urinary bladder radiation injury

    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%).

  6. Molecular mechanism of adaptive response to low dose radiation

    Adaptive response is a term used to describe the ability of a low, priming dose of ionizing radiation to modify the effects of a subsequent higher, challenge dose. Molecular mechanism of adaptive response to low dose radiation is involved in signal transduction pathway, reactive oxygen species, DNA damage repair

  7. Comparison of particle-radiation-therapy modalities

    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

  8. Lymphocyte chromosome aberrations in partial-body fractionated radiation therapy

    a relationship between lymphocyte chromosome aberration yields which occur in partial-body fractionated radiation therapy and those yields measured in vitro is derived. These calculations are applied to the case of patients undergoing radiation therapy for mammary carcinoma. (author)

  9. Lymphocyte chromosome aberrations in partial-body fractionated radiation therapy

    Ekstrand, K.E.; Dixon, R.L. (Wake Forest Univ., Winston-Salem, NC (USA))

    1982-03-01

    a relationship between lymphocyte chromosome aberration yields which occur in partial-body fractionated radiation therapy and those yields measured in vitro is derived. These calculations are applied to the case of patients undergoing radiation therapy for mammary carcinoma.

  10. Tumor trailing strategy for intensity-modulated radiation therapy of moving targets

    Trofimov, Alexei; Vrancic, Christian; Chan, Timothy C. Y.; Sharp, Gregory C.; Bortfeld, Thomas

    2008-01-01

    Internal organ motion during the course of radiation therapy of cancer affects the distribution of the delivered dose and, generally, reduces its conformality to the targeted volume. Previously proposed approaches aimed at mitigating the effect of internal motion in intensity-modulated radiation therapy (IMRT) included expansion of the target margins, motion-correlated delivery (e.g., respiratory gating, tumor tracking), and adaptive treatment plan optimization employing a probabilistic descr...

  11. Migratory organizing pneumonitis `primed` by radiation therapy

    Bayle, J.Y.; Nesme, P.; Guerin, J.C. [Hopital de la Croix Rousse, Service de Pneumologie, Lyon (France); Bejui-Thivolet, F. [Hopital de la Croix Rousse, Laboratorie d`Anatomopatologie, Lyon (France); Loire, R. [Hopital Cardiovasculaire et Pneumologique, Universite Claude Bernard, Laboratoire d`Anatomopathologie, Lyon (France); Cordier, J.F. [Hopital Cardiovasculaire et Pneumologique, Universite Claude Bernard, Service de Pneumologie, Lyon (France)

    1995-02-01

    We report on two women presenting with cough and fever, 4 and 7 months, respectively, after starting breast radiation therapy following surgery for breast carcinoma. Chest roentgenogram and computed tomographic (CT) scan demonstrated alveolar opacities, initially limited to the pulmonary area next to the irradiated breast, but later migrating within both lungs. Intra-alveolar granulation tissue was found in transbronchial lung biopsies. Corticosteroid treatment resulted in dramatic clinical improvment, together with complete clearing of the pulmonary opacities on chest imaging. However, clinical and imaging relapses occurred when corticosteroids were withdrawn too rapidly; with further improvment when they were reintroduced. The reported cases clearly differ from radiation pneumonitis. They were fairly typical of cryptogenic organizing pneumonitis, also called idiopathic bronchiolitis obliterans organizing pneumonia, with the exception of the radiation therapy, partially affecting the lung, which had been performed within the previous months. Since focal radiation therapy involving the lung may induce diffuse bilateral lymphocytic alveolitis, we hypothesize that this may `prime` the lung to further injury, leading to cryptogenic organizing pneumonitis. (au) (26 refs.).

  12. Migratory organizing pneumonitis 'primed' by radiation therapy

    We report on two women presenting with cough and fever, 4 and 7 months, respectively, after starting breast radiation therapy following surgery for breast carcinoma. Chest roentgenogram and computed tomographic (CT) scan demonstrated alveolar opacities, initially limited to the pulmonary area next to the irradiated breast, but later migrating within both lungs. Intra-alveolar granulation tissue was found in transbronchial lung biopsies. Corticosteroid treatment resulted in dramatic clinical improvment, together with complete clearing of the pulmonary opacities on chest imaging. However, clinical and imaging relapses occurred when corticosteroids were withdrawn too rapidly; with further improvment when they were reintroduced. The reported cases clearly differ from radiation pneumonitis. They were fairly typical of cryptogenic organizing pneumonitis, also called idiopathic bronchiolitis obliterans organizing pneumonia, with the exception of the radiation therapy, partially affecting the lung, which had been performed within the previous months. Since focal radiation therapy involving the lung may induce diffuse bilateral lymphocytic alveolitis, we hypothesize that this may 'prime' the lung to further injury, leading to cryptogenic organizing pneumonitis. (au) (26 refs.)

  13. Hyperbaric oxygen therapy for radiation cystitis

    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)

  14. Study on physical penumbra of radiation therapy

    Kim, Young Bum; Whang, Woong Ku [Korea University Medical Center, Seoul (Korea, Republic of); Kim, You Hyun [Junior College of Allied Health Science, Korea University, Seoul (Korea, Republic of)

    1993-12-15

    Proper evaluation about the penumbra is very important to improve the efficacy of radiation therapy. There are two kinds of physical penumbra, geometric penumbra and transmission penumbra. In this study, we evaluated the variation of physical penumbra according to the varing energy level, changing the field size and depth. Physical penumbra width was decreased as the source size decreased, and as the SDD increased, but the consideration about the scatter radiation and mechanical stability is an important factor. For the two adjacent beams, upper collimator should be used and especially for Co-60 unit, it is efficient to use the extended collimator.

  15. Hyperbaric oxygen therapy for radiation cystitis

    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)

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

    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

  17. Curative radiation therapy in prostate cancer

    Radiotherapy has experienced an extremely rapid development in recent years. Important improvements such as the introduction of multileaf collimators and computed tomography (CT)-based treatment planning software have enabled three dimensional conformal external beam radiation therapy (3DCRT). The development of treatment planning systems and technology for brachytherapy has been very rapid as well. Development of accelerators with integrated on-board imaging equipment and technology, for example image-guided radiation therapy (IGRT) has further improved the precision with reduced margins to adjacent normal tissues. This has, in turn, led to the possibility to administer even higher doses to the prostate than previously. Although radiotherapy and radical prostatectomy have been used for the last decades as curative treatment modalities, still there are no randomized trials published comparing these two options. Outcome data show that the two treatment modalities are highly comparable when used for low- and intermediate-risk prostate cancer

  18. Radiation therapy for head and neck cancers

    Radiation therapy may be indicated for larger invasive tumors of the head and neck that may be difficult to surgically excise or for which surgery would be significantly disfiguring. Previous studies of oral squamous cell carcinomas indicate that it should be possible to control approximately 80% of all but the most advanced local or locoregional tumors. Aggressive radiation therapy to total doses of 56 Gy or greater may be required. That can be done by using smaller doses per fraction and gradually reducing the size of the field so that the highest dose is given only to the tumor with a relatively tight margin. Malignant melanomas can be controlled locally apparently with a few large fractions. Metastatic disease limits survival; therefore, some type of systemic therapy seems to be needed to improve survival of those patients. Canine oral fibrosarcomas require a very high dose for a reasonable probability of control. It seems that a dose of 56 Gy given in 3.3 Gy fractions might provide local control of 50% of the tumors. It is likely that a combination of surgery and radiation would significantly improve the probability for control. Oral squamous cell carcinomas of cats must also be treated very aggressively to improve local control. Tumors of the nasal cavity are usually very large and invasive at the time of diagnosis. Radiation therapy has been shown to be effective in some instances. It is possible that with better definition of the tumor through computerized tomography imaging and improved treatment planning, control of these difficult to manage nasal tumors can be improved

  19. Lacrimal gland lymphoma: Role of radiation therapy

    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...

  20. Perspectives of radiation therapy in benign diseases

    Purpose: the numbers of patients with nonmalignant diseases referred for radiation therapy had to be evaluated for the last 4 years. Patients and methods: in the years 2002, 2004, and 2005 radiation therapy was performed in 61, 40, and 26 patients, respectively. Regularly, more women than men were treated, median age annually was 57, 54, and 55 years, respectively (table 1). The radiotherapy scheme was not modified within the evaluated period. Results: the proportion of nonmalignant diseases among all patients treated decreased from 4.7% in 2002 to 3.3% in 2004 and 2.2% in 2005, respectively. A shift was noticed toward the treatment of four main diseases (endocrine orbitopathy, prevention of heterotopic ossification, meningeoma, tendinitis, table 2). The number of referring physicians decreased from 19 to six. Conclusion: due to administrative restrictions for treatment in hospitals, budget restrictions in private practices and lasting, insufficient revenues for radiotherapy in nonmalignant diseases, radiation therapy for the entire group of benign diseases is endangered. (orig.)

  1. Radiation Therapy in Elderly Skin Cancer

    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

  2. Radiation therapy for unresected gastric lymphoma

    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)

  3. Chronic neuroendocrinological sequelae of radiation therapy

    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.

  4. Chronic neuroendocrinological sequelae of radiation therapy

    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

  5. Delayed radiation effect on animals: adaptive reply

    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)

  6. Dosimetric advantages of proton therapy compared with photon therapy using an adaptive strategy in cervical cancer.

    van de Schoot, Agustinus J A J; de Boer, Peter; Crama, Koen F; Visser, Jorrit; Stalpers, Lukas J A; Rasch, Coen R N; Bel, Arjan

    2016-07-01

    Background Image-guided adaptive proton therapy (IGAPT) can potentially be applied to take into account interfraction motion while limiting organ at risk (OAR) dose in cervical cancer radiation therapy (RT). In this study, the potential dosimetric advantages of IGAPT compared with photon-based image-guided adaptive RT (IGART) were investigated. Material and methods For 13 cervical cancer patients, full and empty bladder planning computed tomography (CT) images and weekly CTs were acquired. Based on both primary clinical target volumes (pCTVs) [i.e. gross tumor volume (GTV), cervix, corpus-uterus and upper part of the vagina] on planning CTs, the pretreatment observed full range primary internal target volume (pITV) was interpolated to derive pITV subranges. Given corresponding ITVs (i.e. pITVs including lymph nodes), patient-specific photon and proton plan libraries were generated. Using all weekly CTs, IGART and IGAPT treatments were simulated by selecting library plans and recalculating the dose. For each recalculated IGART and IGAPT fraction, CTV (i.e. pCTV including lymph nodes) coverage was assessed and differences in fractionated substitutes of dose-volume histogram (DVH) parameters (V15Gy, V30Gy, V45Gy, Dmean, D2cc) for bladder, bowel and rectum were tested for significance (Wilcoxon signed-rank test). Also, differences in toxicity-related DVH parameters (rectum V30Gy, bowel V45Gy) were approximated based on accumulated dose distributions. Results In 92% (96%) of all recalculated IGAPT (IGART) fractions adequate CTV coverage (V95% >98%) was obtained. All dose parameters for bladder, bowel and rectum, except the fractionated substitute for rectum V45Gy, were improved using IGAPT. Also, IGAPT reduced the mean dose to bowel, bladder and rectum significantly (p photon-based IGART, IGAPT maintains target coverage while significant dose reductions for the bladder, bowel and rectum can be achieved. PMID:26934821

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

    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

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

    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 mm3 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

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

    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.

  10. Image-guided radiation therapy: Physician′s perspectives

    T Gupta

    2012-01-01

    Full Text Available The evolution of radiotherapy has been ontogenetically linked to medical imaging. Over the years, major technological innovations have resulted in substantial improvements in radiotherapy planning, delivery, and verification. The increasing use of computed tomography imaging for target volume delineation coupled with availability of computer-controlled treatment planning and delivery systems have progressively led to conformation of radiation dose to the target tissues while sparing surrounding normal tissues. Recent advances in imaging technology coupled with improved treatment delivery allow near-simultaneous soft-tissue localization of tumor and repositioning of patient. The integration of various imaging modalities within the treatment room for guiding radiation delivery has vastly improved the management of geometric uncertainties in contemporary radiotherapy practice ushering in the paradigm of image-guided radiation therapy (IGRT. Image-guidance should be considered a necessary and natural corollary to high-precision radiotherapy that was long overdue. Image-guided radiation therapy not only provides accurate information on patient and tumor position on a quantitative scale, it also gives an opportunity to verify consistency of planned and actual treatment geometry including adaptation to daily variations resulting in improved dose delivery. The two main concerns with IGRT are resource-intensive nature of delivery and increasing dose from additional imaging. However, increasing the precision and accuracy of radiation delivery through IGRT is likely to reduce toxicity with potential for dose escalation and improved tumor control resulting in favourable therapeutic index. The radiation oncology community needs to leverage this technology to generate high-quality evidence to support widespread adoption of IGRT in contemporary radiotherapy practice.

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

    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

  12. External beam radiation therapy for prostate cancer

    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. Palliative radiation therapy for multiple myeloma

    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)

  14. Translation and adaptation procedures for music therapy outcome instruments

    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....... A literature review identified a knowledge gap regarding translation procedures of outcome measures used in music therapy research. However, a large body of translation guidelines is available in other health professions. We used the guidelines from these related fields to identify guidelines and...... outline procedural steps for the translation and adaptation of music therapy outcome instruments. OBS: 50 free online copies to share: http://www.tandfonline.com/eprint/d8TPZbkVMjzgKg7DjcmT/full...

  15. State of the art of radiation therapy for esophageal cancer

    Radiation therapy has a critical role in the treatment of esophageal cancer. To improve the treatment outcome of radiotherapy, not only strengthening the treatment intensity but also decreasing the long term toxicity is needed. To reduce the long term cardiopulmonary toxicity of chemoradiation, JCOG is now running a clinical trial which combines three dimensional conformal radiation therapy (3D-CRT) and mild irradiation dose. New techniques of radiation therapy, such as intensity modulated radiation therapy (IMRT) or particle therapy are also promising in both treatment intensity and decreased toxicity. (author)

  16. Memory and survival after microbeam radiation therapy

    Background: Disturbances of memory function are frequently observed in patients with malignant brain tumours and as adverse effects after radiotherapy to the brain. Experiments in small animal models of malignant brain tumour using synchrotron-based microbeam radiation therapy (MRT) have shown a promising prolongation of survival times. Materials and methods: Two animal models of malignant brain tumour were used to study survival and memory development after MRT. Thirteen days after implantation of tumour cells, animals were submitted to MRT either with or without adjuvant therapy (buthionine-SR-sulfoximine = BSO or glutamine). We used two orthogonal 1-cm wide arrays of 50 microplanar quasiparallel microbeams of 25 μm width and a center-to-center distance of about 200 μm, created by a multislit collimator, with a skin entrance dose of 350 Gy for each direction. Object recognition tests were performed at day 13 after tumour cell implantation and in monthly intervals up to 1 year after tumour cell implantation. Results: In both animal models, MRT with and without adjuvant therapy significantly increased survival times. BSO had detrimental effects on memory function early after therapy, while administration of glutamine resulted in improved memory

  17. Megavoltage radiation therapy: Meeting the technological needs

    Full text: In its simplest description, the purpose of radiation therapy is to hit the target and to miss all other parts of the patient. While there are multiple technological methods available for doing this, the actual radiation treatment needs to be considered in the broader context of the total radiation treatment process. This process contains multiple steps, each of which has an impact on the quality of the treatment and on the possible clinical outcome. One crucial step in this process is the determination of the location and extent of the disease relative to the adjacent normal tissues. This can be done in a variety of ways, ranging from simple clinical examination to the use of complex 3-D imaging, sometimes aided by contrast agents. As part of this localization process, it is very important that patient immobilization procedures be implemented to ensure that the same patient position will be used during both the planning and the daily treatment stages. With the knowledge of the location of the target and the critical tissues, decisions can be made about the appropriate beam arrangements to provide adequate tumour coverage while sparing the healthy tissues. This beam arrangement may have to be confirmed on a therapy simulator prior to actual implementation of the radiation treatment. In summary, the treatment process includes diagnosis, patient immobilization, target and normal tissue localization, beam selection, beam shaping, dose calculation, technique optimization, simulation, prescription, treatment verification and, finally, treatment. Dependent on the type of disease, it is not necessary that every patient undergoes all of the steps in the process; however, it is necessary that each step of the process used for a particular patient be carried out with the greatest accuracy. Uncertainties at any stage of the process will be carried through to subsequent stages and have an impact on clinical outcome. It is, therefore, important to recognize, when

  18. Why do patients drop out during radiation therapy?

    This study is to see how much proportion of the patients receiving radiation therapy drop out during radiation therapy and to analyze the reason for the incomplete treatment. The base population of this study was 1,100 patients with registration numbers 901 through 2,000 at Department of Radiation Oncology, Samsung Medical Center, Seoul, Korea. Authors investigated the incidence of incomplete radiation therapy, which was defined as less than 95% of initially planned radiation dose, and the reasons for incomplete radiation therapy. One hundred and twenty eight patients (12%) did not complete the planned radiation therapy. The performance status of the incompletely treated patients was generally poorer than that of the base population, and the aim of radiation therapy was more commonly palliative. The most common reason for not completing the planned treatment was the patients' refusal of further radiation therapy because of the distrust of radiation therapy and/or the poor economic status. Careful case selection for radiation therapy with consideration of the socioeconomic status of the patients in addition to the clinical indication would be necessary for the reduction of incomplete treatment, especially in the palliative setting

  19. Impact of radiation therapy for benign diseases

    Radiation therapy of benign diseases represent a wide panel of indications. Some indications are clearly identified as treatment of arteriovenous malformations (AVM), hyperthyroid ophthalmopathy, postoperative heterotopic bone formations or keloid scars. Some indications are under evaluation as complications induced by neo-vessels of age-related macular degeneration or coronary restenosis after angioplasty. Some indications remain controversial with poor evidence of efficiency as treatment of bursitis, tendinitis or Dupuytren's disease. Some indications are now obsolete such as warts, or contra-indicated as treatment of infant and children. (authors)

  20. Mini-TEPCs for radiation therapy

    A mini-tissue-equivalent proportional-counter (TEPC) has been constructed to study the possibility to manufacture mini-counters without field-shaping tubes for radiation therapy. The mini-TEPC can be assembled with and without field-shaping tubes. It can be equipped with a mini-alpha source for a precise lineal energy calibration. After the positive conclusions of this study, a slim TEPC has been designed and constructed. The slim TEPC has an external diameter of only 2.7 mm. It has been tested with therapeutic proton beams and gamma ray sources. (authors)

  1. New irradiation geometry for microbeam radiation therapy

    Microbeam radiation therapy (MRT) has the potential to treat infantile brain tumours when other kinds of radiotherapy would be excessively toxic to the developing normal brain. MRT uses extraordinarily high doses of x-rays but provides unusual resistance to radioneurotoxicity, presumably from the migration of endothelial cells from 'valleys' into 'peaks', i.e., into directly irradiated microslices of tissues. We present a novel irradiation geometry which results in a tolerable valley dose for the normal tissue and a decreased peak-to-valley dose ratio (PVDR) in the tumour area by applying an innovative cross-firing technique. We propose an MRT technique to orthogonally crossfire two arrays of parallel, nonintersecting, mutually interspersed microbeams that produces tumouricidal doses with small PVDRs where the arrays meet and tolerable radiation doses to normal tissues between the microbeams proximal and distal to the tumour in the paths of the arrays

  2. Individual skin care during radiation therapy

    Background: In many clinical settings, the irradiated patient feels additional discomfort by the inhibition of washing the treatment portals and interruption of his adapted skin care habits. Material and methods: An analysis of the scientific recommendations as well as an analysis of the skin dose to the irradiated portals has been performed. An individual scheme for skin care under radiation has been developed. Results: A substantial decrease of the skin dose is achieved in many modern radiation techniques. The consequent reduction of severe skin reactions allowed the use of water and mild soaps as has been approved within many radiotherapy departments. This has lead to an individualized concept for skin care under radiation treatment including the allowance of gentle washing. The skin marks may be saved by using highly tolerable adhesive plasters or small tattoo points, if they are not superfluous by using masks or single referee points instead of marks for the field borders. Conclusions: The individualized concept for skin care during radiation may offer improved life quality to the patient and may decrease the acute reactions of the skin at least in some cases. (orig.)

  3. The preventation of radiation accidents in radiation therapy

    The radio-therapy planning system (RTPS) has improved the speed and accuracy of dose calculation and has come to be used in most hospitals in recent years. The RTPS calculated monitor unit (MU) defines the dose delivered to the patient. Radiation accidents caused by wrong MU calculated by erroneous basic data registration has frequently been reported in Japan. We investigated the MU calculated with the RTPS of this hospital. The measurement value resulted in the permissible error range set by the AAPM13 TG24 report. The basic data registered in the RTPS of this hospital and calculated MU were proven to be proper. (author)

  4. Emerging Canadian QA standards for radiation therapy

    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

  5. Involvement of Toll-like receptors in acute radiation syndrome and radiation therapy for cancer

    Toll-like receptors (TLR) are one of pattern recognition receptors that are indispensable for antibacterial and antiviral immunity. After TLRs sense pathogen-derived components, they activate intracellular signaling pathways, which results in the induction of proinflammatory cytokines. Although it is well known that radiation therapy is one of effective cancer therapies, radiation affects immune system. Recent evidences show the involvement of TLR in acute radiation syndrome and radiation therapy for cancer. I summarize to date knowledge on the involvement of Toll-like receptors in acute radiation syndromes and radiation therapy for cancer, and discuss the effects of ionizing radiation on TLR of innate immune cells. (author)

  6. Clinical applications of continuous infusion chemotherapy ahd concomitant radiation therapy

    This book presents information on the following topics: theoretical basis and clinical applications of 5-FU as a radiosensitizer; treatment of hepatic metastases from gastro intestingal primaries with split course radiation therapy; combined modality therapy with 5-FU, Mitomycin-C and radiation therapy for sqamous cell cancers; treatment of bladder carcinoma with concomitant infusion chemotherapy and irradiation; a treatment of invasiv bladder cancer by the XRT/5FU protocol; concomitant radiation therapy and doxorubicin by continuous infusion in advanced malignancies; cis platin by continuous infusion with concurrent radiation therapy in malignant tumors; combination of radiation with concomitant continuous adriamycin infusion in a patient with partially excised pleomorphic soft tissue sarcoma of the lower extremeity; treatment of recurrent carcinoma of the paranasal sinuses using concomitant infusion cis-platinum and radiation therapy; hepatic artery infusion for hepatic metastases in combination with hepatic resection and hepatic radiation; study of simultaneous radiation therapy, continuous infusion, 5FU and bolus mitomycin-C; cancer of the esophagus; continuous infusion VP-16, bolus cis-platinum and simultaneous radiation therapy as salvage therapy in small cell bronchogenic carcinoma; and concomitant radiation, mitomycin-C and 5-FU infusion in gastro intestinal cancer

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

    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)

  8. Radiation therapy of psoriasis and parapsoriasis

    Selective UV-Phototherapy with lambda 300-320 nm (SUP) as well as oral photochemotherapy with 8-methoxy-psoralen plus UVA-radiation (PUVA intern) are very effective in clearing the lesions of the generalized psoriasis and those of the chronic forms of parapsoriasis. Being treated with 4 suberythemal doses per week psoriasis patients are free or nearly free of symptoms after averagely 6.3 weeks of SUP-therapy or after 5.3 weeks of PUVA orally. The PUVA-therapy is mainly indicated in pustular, inverse and erythrodermic psoriasis as well as in parapsoriasis en plaques and variegata. In all other forms of psoriasis and in pityriasis lichenoides-chronica, we prefer the SUP-therapy because of less acute or chronic side effects, and because of its better practicability. X-rays are indicated in psoriais of nails, grenz-rays in superficial psoriatic lesions of the face, the armpits, the genitals and the anal region. (orig.)

  9. How Should I Care for Myself During Radiation Therapy?

    ... patients to be advocates. View more information How Should I Care for Myself During Radiation Therapy? Get ... decrease some of their treatment-related fatigue. You should ask your radiation oncologist what the best form ...

  10. Megavoltage radiation therapy: Meeting the technological needs

    The process of radiation therapy is complex and contains multiple steps, each of which has an impact on the quality of the treatment and on the possible clinical outcome. This treatment process includes diagnosis, patient immobilization, target and normal tissue localization, beam selection, beam shaping, dose calculation, technique optimization, simulation, prescription, treatment verification and, finally, the actual radiation treatment. Depending on the type of disease, it is not necessary that every patient undergo all the steps in the process; however, it is necessary that each step of the process used for a particular patient be carried out with the greatest accuracy. Inaccuracies at any stage of the process will be carried through to subsequent stages and have an impact on clinical outcome. It is therefore important to recognize, when addressing technological needs for megavoltage radiation treatment, that the radiation treatment machine technology should not be considered in isolation from the technologies associated with the other steps of the treatment process. In the purchase of radiation treatment equipment in any country, the following should be considered: (a) the availability and reliability of a country's physical infrastructure; (b) financial considerations; (c) the types and stages of disease most likely to be treated; (d) the number and types of professional staff available to apply the treatment technologies; (e) professional staff training and continuing education resources; (f) the number of patients requiring treatment with the treatment equipment available (i.e. the efficient use of available resources); (g) the treatment planning technologies (e.g. immobilization, imaging and the treatment planning computer) available to prepare the patient for the actual irradiation procedure; (h) the technological considerations of the therapy equipment in the context of the above factors (e.g. 60Co versus linac); (i) the cost of maintenance and local

  11. Adaptive search and detection of laser radiation

    Formation of cosmic optical line connected with the solving of difficult problems, among which stand out spatial search task, detection and target tracking. Indeed, the main advantage of systems of the optical diapason, high radiation direction leads to a challenging task of entering in communication, consisting in mutual targeting antenna receiving and transmitting systems. Algorithm detection, obtained by solving the corresponding statistical optimal detection test synthesis tasks detector determines the structure and quality of his work which depend on the average characteristics of the signal and the background radiation of the thermal noise require full priori certainty about the conditions of observation. Algorithm of the optimal detector of laser light modulated on a sub carrier frequency of intensity assumes a priori known intensity and efficiency background radiation and internal noise power photo detector

  12. Potential for heavy particle radiation therapy

    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

  13. Radiation therapy for carcinoma of the ear

    Carcinoma of the ear is rarely reported. From 1978 through 1992, we treated 9 patients, of whom 5 had malignant tumors of the external auditory canal and 4 had malignant tumors of the middle ear, with radiation. These patients accounted for only 0.9% of all patients with head and neck carcinomas treated with radiation at our hospital. Most patients had otorrhea and otalgia, but few patients had specific symptoms of carcinoma. The outcome in cases in which radiotherapy was given after tumor was completely resected was good. The overall 5-year survival rate was 55%. In addition, the 3-year survival rates in cases of carcinoma of the middle ear and of the external auditory canal were 50% and 60%. However, there was no statistical difference in 5-year survival rates between the two sites. We believe factors that affect prognosis are early diagnosis of malignant change, the area of tumor involvement at diagnosis, and combined therapy with surgery and radiation. (author)

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

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

    2014-07-15

    Persons with Parkinson's disease (PD) are characterized by multifactorial gait deficits, though the factors which influence the abilities of persons with PD to adapt and store new gait patterns are unclear. The purpose of this study was to investigate the effects of dopaminergic therapy on the abilities of persons with PD to adapt and store gait parameters during split-belt treadmill (SBT) walking. Ten participants with idiopathic PD who were being treated with stable doses of orally-administered dopaminergic therapy participated. All participants performed two randomized testing sessions on separate days: once while optimally-medicated (ON meds) and once after 12-h withdrawal from dopaminergic medication (OFF meds). During each session, locomotor adaptation was investigated as the participants walked on a SBT for 10 min while the belts moved at a 2:1 speed ratio. We assessed locomotor adaptive learning by quantifying: (1) aftereffects during de-adaptation (once the belts returned to tied speeds immediately following SBT walking) and (2) savings during re-adaptation (as the participants repeated the same SBT walking task after washout of aftereffects following the initial SBT task). The withholding of dopaminergic medication diminished step length aftereffects significantly during de-adaptation. However, both locomotor adaptation and savings were unaffected by levodopa. These findings suggest that dopaminergic pathways influence aftereffect storage but do not influence locomotor adaptation or savings within a single session of SBT walking. It appears important that persons with PD should be optimally-medicated if walking on the SBT as gait rehabilitation. PMID:24698798

  15. Melanomas: radiobiology and role of radiation therapy

    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

  16. Radiation reactions and injuries, their prophylaxis and therapy

    The most frequent local and total radiation reactions (epithema, dry and wet epidermitises, esophagitises, radiation variations of pulmonary tissues, the reaction of mucous membrane of the rectum, radiation cystitises) are described. The problems on delayed radiation injuries (delayed skin injuries, injuries of intestine, limbs, lungs, heart, organs of urochesia) are considered. Delayed radiation injuries are shown to be expected, if the tolerant level of healthy tissues irradiated increases during radiotherapy. Special attention is paid to prophylaxis and radiation injuries therapy

  17. How can we overcome tumor hypoxia in radiation therapy?

    Local recurrence and distant metastasis frequently occur after radiation therapy for cancer and can be fatal. Evidence obtained from radiochemical and radiobiological studies has revealed these problems to be caused, at least in part, by a tumor-specific microenvironment, hypoxia. Moreover, a transcription factor, hypoxia-inducible factor 1 (HIF-1), was identified as pivotal to hypoxia-mediated radioresistance. To overcome the problems, radiation oncologists have recently obtained powerful tools, such as 'simultaneous integrated boost intensity-modulated radiation therapy (SIB-IMRT), which enables a booster dose of radiation to be delivered to small target fractions in a malignant tumor', 'hypoxia-selective cytotoxins/drugs', and 'HIF-1 inhibitors' etc. In order to fully exploit these innovative and interdisciplinary strategies in cancer therapy, it is critical to unveil the characteristics, intratumoral localization, and dynamics of hypoxia/HIF-1-active tumor cells during tumor growth and after radiation therapy. We have performed optical imaging experiments using tumor-bearing mice and revealed that the locations of HIF-1-active tumor cells changes dramatically as tumors grow. Moreover, HIF-1 activity changes markedly after radiation therapy. This review overviews fundamental problems surrounding tumor hypoxia in current radiation therapy, the function of HIF-1 in tumor radioresistance, the dynamics of hypoxic tumor cells during tumor growth and after radiation therapy, and how we should overcome the difficulties with radiation therapy using innovative interdisciplinary technologies. (author)

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

    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

  19. Use of molecular imaging to guide and assess radiation therapy

    Imaging is intimately associated with radiation therapy (RT). Anatomical imaging is the standard of care for crucial components of the RT process such as tumor localization, treatment planning, and positioning verification. However, as disease progression and treatment response at the molecular and cellular level precede visible structural changes to tissue, applications of functional and molecular imaging are becoming increasingly more important. Use of molecular imaging in RTcan be divided into three phases: (1) Imaging for diagnosis and staging, performed during the initial phases of RT to establish the presence and progression of disease (2) Imaging for target definition, performed prior to RT in order to determine the spatial extent of the tumor and the position of normal tissue (3) Imaging for treatment response assessment, performed during or after RT to establish effectiveness, predict outcome, and potentially modify therapy. Following diagnosis and staging molecular imaging can help to define which type of therapy should be used, as well assess the spatial extent of the tumor, thus providing grounds for more reliable target definition. Molecular imaging has been shown to significantly reduce large inter-observer variability in target definition compared to anatomical imaging. This reduction leads to significant reduction in treatment margin, thereby enabling more accurate and precise tumor targeting. Furthermore, molecular imaging has the potential to characterize biological heterogeneity within tumors, providing foundations for so-called biologically conformal radiotherapy, or dose painting. Early treatment response assessment refers to the use of molecular imaging during the course of therapy, and late treatment response assessment refers to the use of molecular imaging after the therapy has been completed. While late assessment enables prediction of treatment outcome, early assessment, in addition, enables treatment adaptation

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

    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 ...

  1. Radiation therapy for carcinoma of the vulva

    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)

  2. Clinical results of radiation therapy for thymoma

    Masunaga, Shin-ichiro; Ono, Koji; Hiraoka, Masahiro; Sasai, Keisuke; Kitakabu, Yoshizumi; Abe, Mitsuyuki (Kyoto Univ. (Japan). Faculty of Medicine); Takahashi, Masaji; Tsutsui, Kazushige; Fushiki, Masato

    1992-05-01

    From August 1968 to December 1989, 58 patients with thymoma were treated by radiotherapy using cobalt-60 gamma ray. Eleven cases were treated by radiothrapy alone, 1 by preoperative radiotheapy, 43 by postoperative radiotherapy, and 3 in combination with intraoperative radiotherapy. The following points were clarified: (a) Postoperative and intraoperative radiotherapy were effective; (b) For postoperative radiotherapy, operability was the major factor influencing survival and local control, and Stage I and II tumors resected totally or subtotally as well as Stage III tumors resected totally were good indications for such therapy; (c) The patients with complicating myasthenia gravis had a longer survival time and better local control rate than those without it. Radiation pneumonitis was observed in 17 patients, and none of them died of this complication. In all cases in combination with intraoperative radiotherapy, dry desquamation was observed within the irradiated field. (author).

  3. Definition of treatment geometry in radiation therapy

    When accurate systems for quality assurance and treatment optimization are employed, a precise system for fixation and dosimetric and portal verification are as important as a continued and standardized code of practice for dosimetry and patient follow-up, including registration of tumour responses and acute and late normal tissue reactions. To improve the accuracy of existing dose response relations in order to improve future therapy the treatment geometry and dose delivery concepts have to be accurately defined and uniformly employed. A Nordic working group was set up in 1991 (by Nordic Association of Clinica Physics) to standardize the concepts and quantities used during the whole radiotherapy process in the Nordic countries. Now the group is finalizing its report ''Specification of Dose Delivery in Radiation Therapy''. The report emphasizes that the treatment geometry shall be consistent with the geometry used during the diagnostic work up. The patient fixation is of importance early in the diagnostic phase to ensure that the same reference points and patients position will be used both during the diagnostic work up, simulation and treatment execution. Reference Coordinate System of the patient is a concept based on defined anatomic reference points. This Patient Reference System is a local system which has validity for the tissues, organs and volumes defined during radiotherapy. The reference points of the Patient Reference System should in turn be used for beam set-up. The treatment geometry is then defined by using different concepts describing tissues which are mobile in the Patient Reference System, and finally, volumes which are fixed in this coordinate system. A Set-up Margin has to be considered for movements of the volumes defined in the Reference Coordinate System of the Patient in relation to the radiation beam. The Set-up Margin is dependent on the treatment technique and it is needed in the treatment planning procedure to ensure that the prescribed

  4. Radiation therapy for malignant lid tumor

    The case of a 42-year-old man with Meibomian gland carcinoma in his right lower lid is reported. The tumor found in the nasal part of the lower lid, was 12 mm x 13 mm in size. First, surgical resection was performed. The pathological diagnosis of the frozen section was 'undifferentiated basal cell epithelioma'. Second, cryotherapy was performed all over the cut surface. Later, the permanent section was pathologically diagnosed as 'undifferentiated Meibomian gland carcinoma'. Total 50 Gy irradiation therapy was therefore performed using a 9 Mev Linac electron beam, 25 x 20 mm field, with a lead protector for the cornea and lens. A lead contact lens did not afford good results because it was too easily shifted on the cornea, owing to its weight. Therefore, we made a racket-shaped lead protector. Fixed well with tape, this protector afforded good protective effect. Three years after treatment, the patient has good visual function, with no recurrence. This racket-shaped lead protector is thought to be useful in radiation therapy for malignant lid tumors. (author)

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

    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

  6. Ultraviolet radiation therapy and UVR dose models

    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.

  7. Liver cancer and selective internal radiation therapy

    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

  8. Diagnostic imaging and radiation therapy equipment

    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

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

    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...

  10. Interfraction changes in the brain during radiation therapy

    Our study population consisted of 63 patients with brain tumours treated using image-guided radiation therapy(IGRT). Cranial IGRT corrections were expected to be small, it was found that interfraction changes occurred in a sizable proportion of these radiation therapy patients. Such changes affect clinical target volume coverage and critical structure avoidance. (author)

  11. 21 CFR 892.5840 - Radiation therapy simulation system.

    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...

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

    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

  13. Radiation therapy - what to ask your doctor

    ... 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 - ...

  14. Radiation therapy and photodynamic therapy for biliary tract and ampullary carcinomas

    Saito, Hiroya; Takada, Tadahiro; Miyazaki, Masaru; Miyakawa, Shuichi; Tsukada, Kazuhiro; Nagino, Masato; Kondo, Satoshi; Furuse, Junji; Tsuyuguchi, Toshio; Kimura, Fumio; Yoshitomi, Hideyuki; Nozawa, Satoshi; YOSHIDA, Masahiro; Wada, Keita; Amano, Hodaka

    2008-01-01

    The purpose of radiation therapy for unresectable biliary tract cancer is to prolong survival or prolong stent patency, and to provide palliation of pain. For unresectable bile duct cancer, there are a number of studies showing that radiation therapy is superior to the best supportive care. Although radiation therapy is used in many institutions, no large randomized controlled trials (RCTs) have been performed to date and the evidence level supporting the superiority of this treatment is low....

  15. Radiation pneumonitis after stereotactic radiation therapy for lung cancer

    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.

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

    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)

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

    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.

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

    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

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

    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

  20. Individual skin care during radiation therapy

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

    1998-11-01

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

  1. Conserved sex chromosomes across adaptively radiated anolis lizards

    Rovatsos, M.; Altmanová, M.; Pokorná, Martina; Kratochvíl, L.

    2014-01-01

    Roč. 68, č. 7 (2014), s. 2079-2085. ISSN 0014-3820 R&D Projects: GA ČR GAP506/10/0718 Institutional support: RVO:67985904 Keywords : adaptive radiation * Anolis * reptiles Subject RIV: EG - Zoology Impact factor: 4.612, year: 2014

  2. Optimal approach in early breast cancer: Radiation therapy

    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...

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

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

    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

  5. Adaptive radiation of Espeletia in the cold andean tropics.

    Monasterio, M; Sarmiento, L

    1991-12-01

    The genus Espeletia (Asteraceae) underwent an accelerated adaptive radiation in the new habitats of the high tropical Andes after the retreat of the glaciers. From the ancestral rainforest species, with tree-like forms, the genus diversified at high altitude, developing morphological and physiological adaptations to the peculiar combination of low-temperature, energy and nutrient stresses of the tropical periglacial environments. Espeletia offers an exceptional example of a taxon undergoing a rapid evolutionary process through the colonization of a totally original environment: the cold tropics. Here we review recent research on the ecological, biogeographical, taxonomic, morphological and physiological traits that have led to the adaptive radiation of Espeletia in this extreme habitat. PMID:21232517

  6. Radiation-induced lung injury outside the irradiated area after radiation therapy for breast cancer

    Organizing pneumonia (OP) and eosinophilic pneumonia (EP) are known as lung injuries after radiation therapy for breast cancer. In this study, we reported nine cases of OP and a case of EP after radiation therapy. All 10 women (62±10 years of age) were nonsmokers. Nine patients received endocrine therapy after radiation therapy. The mean intervals from completion of radiation therapy to occurrence of any symptoms were 119 days. All the patients have symptoms, but none are severe. Seven patients were treated with corticosteroids, and three were without treatment. All patients improved, but a relapse occurred in three (two treated with corticosteroid, one without treatment). Because of our findings and the previous studies, tobacco smoke may have played a suppressive role in the occurrence of lung injury in nonirradiated areas after radiation therapy in breast cancer patients, and endocrine therapy may have played a promotive role. (author)

  7. Polymer gel dosimetry system for radiation therapy

    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. Are Organisms Adapting to Ionizing Radiation at Chernobyl?

    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

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

    Wilms, Inge Linda; Rytter, Hana Malá

    Prism Adaptation Therapy (PAT) is an intervention method for treatment of attentional disorders, such as neglect e.g. 1,2. The method involves repeated pointing at specified targets with or without prism glasses using a specifically designed wooden box. The aim of this study was to ascertain...... direct feedback (physical finger) on pointing precision. Attempts to provide feedback indirectly via icons on the computer screen fail to create the aftereffects observed in the original PAT. The findings have direct implications for future implementations of computer-based methods in treatment of...

  10. Clinical impact of new radiation therapy techniques

    Full text: The cornerstone of external beam radiation therapy is the delivery of a therapeutic dose to the target tissues. Traditional '2D' techniques broadly rely on the physician to assimilate the clinical information (history, examination, and radiographs) to define the target volume which is then localized via fluoroscopy on a traditional simulator. This approach required an in-depth understanding of the relationship between surface anatomy, radiographically visible anatomy (i.e. bones on simulator films) and three dimensional soft tissue anatomy. Radiation therapy treatment beams were generally limited to orientations wherein the physician/planner could understand the three dimensional relationship between the internal structures and their projection onto a simulator film. Three dimensional treatment planning allowed the more direct incorporation of three dimensional imaging information into the planning process. The 3D relationship between internal targets and normal tissues seen on 3D imaging (e.g. computed tomography - CT), were therefore more accurately known. This facilitated the use of 'non-standard' beam orientations, and more conformal shaping of the treatment beams. Software allows incorporation of multi-modality three dimensional imaging with, for example, positron emission tomography (PET), magnetic resonance imaging (MRI), and single photon emission computed tomography (SPECT). Therefore, the vast anatomic/functional information from multiple three dimensional imaging modalities can be used in concert to facilitate accurate treatment delivery. Software allows such three dimensional information to be displayed and viewed from any orientation. Beam orientations and shapes are then chosen to encompass the target yet minimize, as possible, normal tissue exposure. Thus, 3D tools allow three dimensional anatomic information to be more accurately incorporated into the planning process. In almost all instances, the target is fully encompassed within each

  11. Recurrent spontaneous pneumothorax after radiation therapy to the thorax

    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.

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

    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.

  13. Radiation Therapy for Chloroma (Granulocytic Sarcoma)

    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.

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

    Jeppesen, Stefan S; 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...... 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....

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

    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. Radianttrademark Liquid Radioisotope Intravascular Radiation Therapy System

    RADIANTtrademark is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid β-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid β-source is Rhenium-188 in the form of sodium perrhenate (NaReO4), Rhenium-188 is primarily a β-emitter with a physical half-life of 17.0 hours. The maximum energy of the β-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified Championtrademark over-the-wire, and TNTtrademark rapid exchange stent delivery balloons. These balloons have thickened polyethylene walls to augment puncture resistance; dual radio-opaque markers and specially configured connectors

  17. Radiation therapy for the solitary plasmacytoma

    Esengül Koçak

    2010-06-01

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

  18. Insufficiency fractures following radiation therapy for gynecologic malignancies

    The purpose of this study was to investigate the incidence, clinical and radiological findings of insufficiency fractures (IF) of the female pelvis following radiation therapy. We retrospectively reviewed the radiation oncology records of 108 patients with gynecologic malignancies who underwent external beam radiation therapy of the whole pelvis. All patients underwent conventional radiography and computed tomography (CT) scan every 6 months in follow-up after radiation therapy and magnetic resonance imaging (MRI) and radionuclide bone scan were added when the patients complained of pelvic pain. Thirteen of 108 patients (12%) developed IF in the irradiated field with a median interval of 6 months (range 3-51) from the completion of external beam radiation therapy. All patients who developed IF were postmenopausal women. Age of the patients who developed IF was significantly higher than that of the other patients. The parts of IF were sacroiliac joints, pubis, sacral body and 5th lumbar vertebra and six of 14 patients had multiple lesions. Treatment with rest and nonsteroidal anti-inflammatory drugs lead to symptomatic relief in all patients, although symptoms lasted from 3 to 20 months. Radiation-induced pelvic IF following radiation therapy for gynecologic malignancies were frequently observed in the post-menopausal patients within 1 year after external beam radiation therapy. Symmetrical fractures of the bilateral sacroiliac joint and pubis were the characteristic pattern of pelvic IF. All patients healed with conservative treatment, and nobody became non-ambulant. (author)

  19. Natural health products and cancer chemotherapy and radiation therapy

    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.

  20. Radiation therapy and host immunity in malignant tumors

    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.)

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

    Abhilash

    2016-03-01

    Full Text Available INTRODUCTION Breast cancer is the most common cancer in women worldwide and a leading cause of cancer death in females and accounts for 1.8 million new cases and approximately 0.5 million deaths annually. Patients who present with locally advanced breast cancer (LABC require multidisciplinary team approach that incorporates diagnostic imaging, surgery, chemotherapy and histopathological assessment, including molecular-based studies, radiation, and, if indicated, biologic and hormonal therapies. Hypofractionated radiation therapy following mastectomy has been used in many institutions for several decades and have demonstrated equivalent local control, cosmetic and normal tissues between 50 Gy in 25 fractions and various hypofractionated radiotherapy prescriptions employing 13-16 fractions. Evidence suggests that hypofractionated radiotherapy may also be safe and effective for regional nodal disease. AIMS AND OBJECTIVES To compare the local control and side effects of hypofractionated radiation therapy with conventional radiation therapy in post mastectomy carcinoma breast with stage II and III and to compare the tolerability and compliance of both schedules. MATERIALS AND METHODS The study was conducted on 60 histopathologically proven patients of carcinoma of breast, treated surgically with modified radical mastectomy. Group I patients were given external radiation to chest flap and drainage areas, a dose of 39 Gy/13 fractions/3.1 weeks, a daily dose 3 Gy for 13 fractions in 4 days a week schedule and Group II patients were given external radiation to chest flap and drainage areas, a dose of 50 Gy/25 fractions/5 weeks, to receive a daily dose 2 Gy for 25 fractions in a 5 days a week schedule. RESULTS The median age at presentation in Group I and II was 48 and 50 years respectively. Locoregional control after completion of radiotherapy in Group I vs. Group II was 26/30 (86.7% vs. 27/30 (90% respectively. Acute reactions and their grades in Group

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

    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)

  3. CT findings of organizing pneumonia after radiation therapy in breast-conserving therapy for breast cancer

    Organizing pneumonia is known as a rare complication after radiation therapy in breast-conserving therapy for breast cancer. CT findings consist of consolidation and ground-glass opacities including the irradiated lung and patchy infiltrates in the nonirradiated lung. Steroid therapy is very effective, but relapse is frequently seen. In relapsed disease, lesions tend to appear in the different site from prior lesions. Radiologists should notice that organizing pneumonia is one form of radiation lung injury with good prognosis. (author)

  4. Stem Cell Therapy Remediates Reconstruction of the Craniofacial Skeleton After Radiation Therapy

    Deshpande, Sagar S.; Gallagher, Kathleen K.; Donneys, Alexis; Tchanque-Fossuo, Catherine N.; Sarhaddi, Deniz; Sun, Hongli; Krebsbach, Paul H; Buchman, Steven R.

    2013-01-01

    This study utilized transplanted bone marrow stromal cells (BMSCs) as a cellular replacement therapy to remedy radiation-induced injury and restore impaired new bone formation during distraction osteogenesis (DO). BMSC therapy brought about the successful generation of new bone and significantly improved both the rate and quality of a bony union of irradiated, distracted [X-ray radiation therapy (XRT)/DO] murine mandibles to the level of nonirradiated DO animals. The bone mineral density and ...

  5. Proton minibeam radiation therapy: Experimental dosimetry evaluation

    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

  6. Mesenchymal stem cell therapy for acute radiation syndrome.

    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

  7. Radiation Therapy Result of Polymorphic Reticulosis

    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.

  8. Results of radiation therapy for medulloblastoma

    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).

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

    Percy eLee

    2012-07-01

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

  10. Advances in Radiation Therapy in Pediatric Neuro-oncology.

    Bindra, Ranjit S; Wolden, Suzanne L

    2016-03-01

    Radiation therapy remains a highly effective therapy for many pediatric central nervous system tumors. With more children achieving long-term survival after treatment for brain tumors, late-effects of radiation have become an important concern. In response to this problem, treatment protocols for a variety of pediatric central nervous system tumors have evolved to reduce radiation fields and doses when possible. Recent advances in radiation technology such as image guidance and proton therapy have led to a new era of precision treatment with significantly less exposure to healthy tissues. These developments along with the promise of molecular classification of tumors and targeted therapies point to an optimistic future for pediatric neuro-oncology. PMID:26271789

  11. Adaptive radiation-induced epigenetic alterations mitigated by antioxidants

    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...

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

    Minni, John; Herold, David

    2015-01-01

    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. PMID:26705443

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

    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...

  14. Natural health products and cancer chemotherapy and radiation therapy

    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...

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

    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)

  16. Factors influencing radiation therapy student clinical placement satisfaction

    Bridge, Pete; Carmichael, Mary-Ann

    2014-01-01

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

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

    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. Persistence of endometrial activity after radiation therapy for cervical carcinoma

    Radiation therapy is a proved treatment for cervical carcinoma; however, it destroys ovarian function and has been thought to ablate the endometrium. Estrogen replacement therapy is often prescribed for patients with cervical carcinoma after radiation therapy. A review of records of six teaching hospitals revealed 16 patients who had endometrial sampling for uterine bleeding after standard radiation therapy for cervical carcinoma. Fifteen patients underwent dilatation and curettage, and one patient underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy when a dilatation and curettage was unsuccessful. Six patients had fibrosis and inflammation of the endometrial cavity, seven had proliferative endometrium, one had cystic hyperplasia, one had atypical adenomatous hyperplasia, and one had adenocarcinoma. Although the number of patients who have an active endometrium after radiation therapy for cervical carcinoma is not known, this report demonstrates that proliferative endometrium may persist, and these patients may develop endometrial hyperplasia or adenocarcinoma. Studies have indicated that patients with normal endometrial glands have an increased risk of developing endometrial adenocarcinoma if they are treated with unopposed estrogen. Patients who have had radiation therapy for cervical carcinoma should be treated with estrogen and a progestational agent to avoid endometrial stimulation from unopposed estrogen therapy

  19. Clinical study on sulpyrin therapy for radiation pneumonitis

    Yagi, Susumu; Watanabe, Masatoshi; Hashiguchi, Kohji; Kimura, Masashi; Sumi, Masaru; Umeki, Shigenobu; Hara, Hiroki; Soejima, Rinzo (Kawasaki Medical School, Kurashiki, Okayama (Japan))

    1990-11-01

    Radiation therapy is an effective treatment for cancer, however, irradiation of the chest may cause radiation pneumonitis as a severe pulmonary complication. Although this condition is responsive to steroid therapy, it is well known that therapy is an increased vulnerability to various infections in patients receiving long-term steroid therapy and exacerbation of the disease associated with a reduction in the dose. In this study, 10 patients with radiation pneumonitis received 3 divided daily oral of 0.9{similar to}1.2 g/day (15 mg/kg) of sulpyrin. The patients' fever disappeared within a few days after the beginning of treatment. Pneumonitis was roentgenographically stabilized, although the fibrotic and atrophic changes continued. No exacerbation of the disease was observed even after discontinuation of the therapy and the outcomes of all patients was satisfactory. These results suggest that sulpyrin was clinically effective for radiation pneumonitis, probably resulting from an anti-inflammatory effect due to prostaglandin synthesis inhibition. In the acute phase of radiation pneumonitis, the introduction of steroids appears to be delayed. This sulpyrin therapy may be a useful alternative for cases in which the steroid therapy in contraindicated. (author).

  20. Radiation dermatitis following electron beam therapy

    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

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

    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

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

    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.

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

    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, AdnexaR, AdnexaL, Prostate, SeminalVesc, PenileBulb, FemurR, and FemurL. 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.

  4. Radiation therapy in the treatment of macular degeneration: a review

    Macular degeneration is a major health problem. Less than 10 % of the cases can be successfully treated by laser therapy. Low dose radiation therapy (in the range of 20 Gy) appears to decrease neo-vascularization. These early results need to be confirmed through a randomized trial. (author)

  5. Optimization of protection of patients in radiation therapy

    Radiotherapy has been one of the main modalities of cancer treatment. Cancer patients are deliberately exposed to high doses of radiation with the aim of complete cure or palliation. Radiation therapy consists of complex processes involving several professionals working in interrelated activities and requiring the use of sophisticated equipment. Optimization of patient protection aims to prevent accidental exposures at any stage of the process. In the course of the treatment, normal tissues receive considerable amount of radiation which can lead to side effects or complications. Optimum treatment is achieved by delivering maximum dose to the target but minimum dose to the critical structures thus decreasing the possibility of developing unwanted complications. There are various ways designed to achieve this objective. These includes the following: the use of customized blocks which has been the standard practice in conventional two-dimensional radiotherapy; the innovative design of the multileaf collimator which together with advancement in imaging techniques and in computer technology have revolutionized the practice of radiotherapy in the last decade leading to the growth of 3-D conformal radiation therapy (3-D CRT) and intensity modulated radiation therapy (IMRT) and finally the use of imaging in image guided radiation therapy (IGRT). These advance techniques in radiation therapy will be discussed in the context of optimization of medical exposures. (author)

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

    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...

  7. Once-Daily Radiation Therapy for Inflammatory Breast Cancer

    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

  8. Once-Daily Radiation Therapy for Inflammatory Breast Cancer

    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

  9. Cranial Radiation Therapy and Damage to Hippocampal Neurogenesis

    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…

  10. The therapy of marrowy syndrome at radiation lesions

    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

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

    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

  12. Dosimetric verification in intensity modulated radiation therapy

    As part of dosimetric verification for IMRT intensity modulated radiation therapy, we examined the selection of a dosimeter in accordance with the purpose of physical measurement and the process of data analysis. Because of the high dose conformation in the target volume and minimum dose in the organs at risk (OAR) in IMRT, dosimetric verification is essential. Because the performance of dosimetric verification in a patient is not allowed, a physical phantom and dosimeter must be used. Dose verification using a physical phantom, from which the beam data optimized for a patient slated for IMRT are transferred, may cause latent error as a result of change in the depth of each beam toward an isocenter. This effect may change the dose distribution and prescription dose. The basic methods of dosimetric verification with physical measurement are point dosimetry, when the reference dose is given at a point by planning software, and volumetric dosimetry, when planning software gives the dose as a volumetric configuration. While the most accurate dosimetry is done using a calibrated ionization chamber, IMRT requires volumetric dosimetry using some kind of portal film or a polymer gel dosimeter, because of the need for dosimetric verification for an irregular dose distribution in IMRT. The importance of indirect dosimetry using these methods is to provide calibration as a dosimeter, absolute dose, and preservation of calibration. In our study, the verification of dose distribution for IMRT using portal film and RANDO phantom could be performed with an error of less than 2% in all cases. The measurement error for the central dose using a JARP-type ionization chamber and MixDP was less than 3% in all cases except for the case with the maximum error. At the moment, IMRT requires a great deal of effort in the processes of planning, dosimetric verification, and isocenter checking in every fraction to maintain high accuracy. Although the need for a large amount of effort in the

  13. Anesthesia for pediatric external beam radiation therapy

    Background: For very young patients, anesthesia is often required for radiotherapy. This results in multiple exposures to anesthetic agents over a short period of time. We report a consecutive series of children anesthetized for external beam radiation therapy (EBRT). Methods: Five hundred twelve children ≤ 16 years old received EBRT from January 1983 to February 1996. Patient demographics, diagnosis, anesthesia techniques, monitoring, airway management, complications, and outcome were recorded for the patients requiring anesthesia. Results: One hundred twenty-three of the 512 children (24%) required 141 courses of EBRT with anesthesia. Anesthetized patients ranged in age from 20 days to 11 years (mean 2.6 ± 1.8 ). The frequency of a child receiving EBRT and requiring anesthesia by age cohort was: ≤ 1 year (96%), 1-2 years (93%), 2-3 years (80%), 3-4 years (51%), 4-5 years (36%), 5-6 years (13%), 6-7 years (11%), and 7-16 years (0.7%). Diagnoses included: primary CNS tumor (28%), retinoblastoma (27%), neuroblastoma (20%), acute leukemia (9%), rhabdomyosarcoma (6%), and Wilms' tumor (4%). Sixty-three percent of the patients had been exposed to chemotherapy prior to EBRT. The mean number of anesthesia sessions per patient was 22 ± 16. Seventy-eight percent of the treatment courses were once daily and 22% were twice daily. Anesthesia techniques included: short-acting barbiturate induction + inhalation maintenance (21%), inhalation only (20%), ketamine (19%), propofol only (12%), propofol induction + inhalation maintenance (7%), ketamine induction + inhalation maintenance (6%), ketamine or short-acting barbiturate induction + inhalation maintenance (6%). Monitoring techniques included: EKG (95%), O2 saturation (93%), fraction of inspired O2 (57%), and end-tidal CO2 (55%). Sixty-four percent of patients had central venous access. Eleven of the 74 children with a central line developed sepsis (15%): 6 of the 11 were anesthetized with propofol (55%), 4 with a short

  14. Image-Guidance for Stereotactic Body Radiation Therapy

    The term stereotactic body radiation therapy (SBRT) describes a recently introduced external beam radiation paradigm by which small lesions outside the brain are treated under stereotactic conditions, in a single or few fractions of high-dose radiation delivery. Similar to the treatment planning and delivery process for cranial radiosurgery, the emphasis is on sparing of adjacent normal tissues through the creation of steep dose gradients. Thus, advanced methods for assuring an accurate relationship between the target volume position and radiation beam geometry, immediately prior to radiation delivery, must be implemented. Such methods can employ imaging techniques such as planar (e.g., x-ray) or volumetric (e.g., computed tomography [CT]) approaches and are commonly summarized under the general term image-guided radiation therapy (IGRT). This review summarizes clinical experience with volumetric and ultrasound based image-guidance for SBRT. Additionally, challenges and potential limitations of pre-treatment image-guidance are presented and discussed

  15. Acute and Chronic Cutaneous Reactions to Ionizing Radiation Therapy

    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...

  16. Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis

    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. Development of medical application methods using radiation. Radionuclide therapy

    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.

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

    In this project, we studied following subjects: 1. development of monoclonal antibodies and radiopharmaceuticals 2. clinical applications of radionuclide therapy 3. radioimmunoguided surgery 4. prevention of restenosis with intracoronary radiation. The results can be applied for the following objectives: 1) radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial. 2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research. 3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology

  19. Radiation Therapy for Neovascular Age-related Macular Degeneration

    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

  20. Radiation Therapy for Neovascular Age-related Macular Degeneration

    Kishan, Amar U. [Harvard Medical School, Boston, Massachusetts (United States); Modjtahedi, Bobeck S.; Morse, Lawrence S. [Department of Ophthalmology and Vision Sciences, University of California, Davis, Sacramento, California (United States); Lee, Percy, E-mail: percylee@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, California (United States)

    2013-03-01

    In the enormity of the public health burden imposed by age-related macular degeneration (ARMD), much effort has been directed toward identifying effective and efficient treatments. Currently, anti-vascular endothelial growth factor (VEGF) injections have demonstrated considerably efficacy in treating neovascular ARMD, but patients require frequent treatment to fully benefit. Here, we review the rationale and evidence for radiation therapy of ARMD. The results of early photon external beam radiation therapy are included to provide a framework for the sequential discussion of evidence for the usage of stereotactic radiation therapy, proton therapy, and brachytherapy. The evidence suggests that these 3 modern modalities can provide a dose-dependent benefit in the treatment of ARMD. Most importantly, preliminary data suggest that all 3 can be used in conjunction with anti-VEGF therapeutics, thereby reducing the frequency of anti-VEGF injections required to maintain visual acuity.

  1. Prototype demonstration of radiation therapy planning code system

    This is the final report of a one-year, Laboratory-Directed Research and Development project at the Los Alamos National Laboratory (LANL). Radiation therapy planning is the process by which a radiation oncologist plans a treatment protocol for a patient preparing to undergo radiation therapy. The objective is to develop a protocol that delivers sufficient radiation dose to the entire tumor volume, while minimizing dose to healthy tissue. Radiation therapy planning, as currently practiced in the field, suffers from inaccuracies made in modeling patient anatomy and radiation transport. This project investigated the ability to automatically model patient-specific, three-dimensional (3-D) geometries in advanced Los Alamos radiation transport codes (such as MCNP), and to efficiently generate accurate radiation dose profiles in these geometries via sophisticated physics modeling. Modem scientific visualization techniques were utilized. The long-term goal is that such a system could be used by a non-expert in a distributed computing environment to help plan the treatment protocol for any candidate radiation source. The improved accuracy offered by such a system promises increased efficacy and reduced costs for this important aspect of health care

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

    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.

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

    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

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

    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.

  5. Therapy palliative with 223Ra without special radiation protection measures?

    For nearly 2 years now as a therapy of the castration resistant prostata carcinoma a nuclide therapy with 223Ra-Dichloride (trade-mark Xofigo) is applied. Xofigo is applied by a medical specialist for nuclear medicine altogether 6 times in a monthly distance. The activity used in each case is according to the body weight (50 kBq/kg BW). This therapy is licensed by the supervisory authorities of the German federal countries as an ambulant therapy. Special radiation protection measures are only required when exceeding a given number of 17 patients per year as incorparation measurements.

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

    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...

  7. Adaptive response induced by occupational exposures to ionizing radiation

    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)

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

    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

  9. Technological progress in radiation therapy for brain tumors

    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.

  10. Radiation therapy for intracranial germ cell tumor

    Shimizu, Wakako; Takizawa, Yoshikazu; Yoshida, Hiroshi; Aruga, Moriyo; Arimizu, Noboru (Chiba Univ. (Japan). School of Medicine); Itami, Jun

    1993-05-01

    From 1974 through 1988, 27 patients with intracranial germ cell tumor underwent radiotherapy in Chiba University Hospital. Radiation field encompassed the whole neuroaxis in 19 patients, the local area in 5, and the whole brain in 3. Overall 5-year survival rate of all 27 patients was 88.9%. There was no significant difference in 5-year overall survival rate between the patients who were treated by the neuroaxis radiation and by the more limited fields. The most significant prognostic factor was pathology of the tumors. Germinoma and histology-unknown tumors which showed good response to irradiation have more favorable prognosis than embryonal carcinoma and choriocarcinoma. From our data, three possibilities emerged: (1) some germinomas might be controlled by localized radiation; (2) optimal dose might be 45[approx]50 Gy; (3) if histology-unknown tumor has good response to radiation at 20 Gy, the tumor can be treated by the same way as germinoma. (author).

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

    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)

  12. Extended-field radiation therapy for carcinoma of the cervix

    The survival of cervical carcinoma patients with paraaortic/high common iliac nodal metastases was evaluated by retrospective chart review during a 13-year interval. Thirty-three patients with cervical carcinoma and surgically documented nodal metastases received primary, extended-field radiation therapy. Overall 2-year and 5-year actuarial survival rates after diagnosis were 37% and 31%, respectively. Survival was analyzed in terms of the variables patient age, clinical stage, tumor histologic type, the presence of enlarged paraaortic/high common iliac lymph nodes, the extent of nodal involvement (microscopic versus macroscopic), the presence of intraperitoneal disease, and whether intracavitary brachytherapy was administered. The use of intracavitary radiation therapy was associated with improved local control and survival (P = 0.017). None of the other variables were statistically related to patient survival. Twenty-two of the patients died of cervical cancer and five are surviving without evidence of cancer. Four patients died of intercurrent disease. Two patients developed bowel-related radiation complications; both patients received chemotherapy concurrent with the radiation therapy. One of the two patients died of radiation enteritis. The use of extended-field radiation therapy does benefit a small group of patients and may result in extended patient survival

  13. Physical basis of heavy ion radiation therapy

    Physical foundation of a heavy ion radio-therapy was discussed, especially on a designing a spread Bragg peak with a ridge filter. A large radiobiological effectiveness will be positively utilized in the heavy ion radio-therapy. The biological effectiveness will be different depending on the depth in human body. This fact gives us difficult problems when we aim to kill uniformly the target cells in human body. As a first step to solve these problems, biological effectiveness of a mixed beam using monoenergetic low and high LET beams was examined and try to understand the results by the amorphous image of the track structure of the heavy ions. A research on a microscopic pattern of energy deposition will be important to solve biophysical problem in heavy ion radio-therapy. (author)

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

    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

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

    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.

  16. Influence of radiation therapy on oral Candida albicans colonization: a quantitative assessment

    An increase in quantity of oral Candida albicans was documented in patients receiving head and neck radiation therapy during and after therapy, as assessed by an oral-rinse culturing technique. The amount of the increase was greater in denture wearers and directly related to increasing radiation dose and increasing volume of parotid gland included in the radiation portal. A significant number of patients who did not carry C. albicans prior to radiation therapy developed positive cultures by 1 month after radiation therapy. The percentage of patients receiving head and neck radiation therapy who carried C. albicans prior to radiation therapy did not differ significantly from matched dental patient controls

  17. A computer based learning program for radiation therapy

    Many textbooks about radiation therapy for the education of medical, technical and scientific staff are available. But they are restricted to transfer of knowledge via text and figures. On the other hand movies and animated pictures can give you a more realistic impression of the procedures and technical equipment of a radiation therapy department. Therefore, an interactive multimedia teaching program was developed at the Universitaets-Krankenhaus Eppendorf for the department of radiation therapy. The electronic textbook runs under 'MS Windows 3.1 trademark ' (with multimedia extensions) and 'MS Windows 95 trademark ', contains eight chapters and can be used without any preliminary knowledge. The program has been tested by medical personnel, nurses, physicists and physicians and was generally welcome. The program was designed for people with different levels of education to reach as many users as possible. It was not created to replace textbooks but was designed for their supplement. (orig.)

  18. Radiation therapy of the nasopharyngeal cancer and its prognostic factors

    39 patients with the regional nasopharyngeal cancer (NPC) underwent radiation therapy from 1975 through 1984 in the Department of Radiology, Chiba University Hospital. A retrospective study was carried out to find out prognostic factors of the NPC patients. Radiation therapy was performed under megavoltage condition. 31 patients were given more than 50 Gy. 41% of the whole had T4 extension and 69% had lymph node metastasis. The pathological slides were reviewed and classified by the proposal of Shanmugaratnam. Advanced N-stage and the absence of the lymphocytic infiltration tended to affect the survival unfavorably, whereas the prognostic significance of histology, especially of keratinizing squamous cell carcinoma remained unclear. T4 lesion often recurred even with high dose radiation therapy. To improve the local control rate in NPC, wide field irradiation from the base of skull to the lower neck seemed necessary as well as the dosage greater than 66 Gy. (orig.)

  19. An international intercomparison of absorbed dose measurements for radiation therapy

    Dose intercomparison on an international basis has become an important component of quality assurance measurement i.e. to check the performance of absorbed dose measurements in radiation therapy. The absorbed dose to water measurements for radiation therapy at the SSDL, MINT have been regularly compared through international intercomparison programmes organised by the IAEA Dosimetry Laboratory, Seibersdorf, Austria such as IAEA/WHO TLD postal dose quality audits and the Intercomparison of therapy level ionisation chamber calibration factors in terms of air kerma and absorbed dose to water calibration factors. The results of these intercomparison in terms of percentage deviations for Cobalt 60 gamma radiation and megavoltage x-ray from medical linear accelerators participated by the SSDL-MINT during the year 1985-2001 are within the acceptance limit. (Author)

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

    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.

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

    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

  2. Determinants of job satisfaction among radiation therapy faculty.

    Swafford, Larry G; Legg, Jeffrey S

    2009-01-01

    Job satisfaction is one of the most significant predictors of employee retention in a variety of occupational settings, including health care and education. A national survey of radiation therapy educators (n = 90) has indicated that respondents are not satisfied with their jobs based on data collected using the Minnesota Satisfaction Questionnaire (MSQ). To predict the factors associated with job satisfaction or dissatisfaction, the authors used a nine-item questionnaire derived from the MSQ. Educators were grouped according to their job satisfaction scores, and multiple discriminant analysis was used to determine which factors were predictive of satisfaction among groups of educators. Statistical results indicate that ability utilization, institutional support, compensation, personnel, and job characteristics were key determinants of job satisfaction among radiation therapy educators. These results may better inform faculty and administration of important factors that can promote job satisfaction and retain faculty in radiation therapy education programs. PMID:19753428

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

    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)

  4. Tracheoinnominate artery fistula as a complication of radiation therapy

    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.

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

    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

  6. Analysis of variations in the dose delivered in radiation therapy

    The outcome of radiotherapy in cancer care is heavily dependent on the quality of the treatment. This work presents a review of how daily practice and the current availability of equipment for treatment planning and simulating as well as a number of other factors affect the radiation therapy quality in Argentina. The establishment of refreshing courses for all types of staffs involved in the treatments, modernization of equipment and strict routines in patient set up and quality control would give a significant contribution to a higher quality in radiation therapy. (author). 3 refs

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

    Khan, Faiz M; Mihailidis, Dimitris

    2011-01-01

    Khan's Lectures: Handbook of the Physics of Radiation Therapy will provide a digest of the material contained in The Physics of Radiation Therapy. Lectures will be presented somewhat similar to a PowerPoint format, discussing key points of individual chapters. Selected diagrams from the textbook will be used to initiate the discussion. New illustrations will used, wherever needed, to enhance the understanding of important concepts. Discussion will be condensed and often bulleted. Theoretical details will be referred to the textbook and the cited literature. A problem set (practice questions) w

  8. [Relapse prevention group therapy for paedophiles: French adaptation].

    Smith, J; Petibon, C

    2005-01-01

    Psychotherapy for sex offenders has only very recently started to develop in France. The French law on compulsory treatment for sex offenders was voted in 1998, and many mental health practitioners are not trained to treat such patients yet. In our ambulatory forensic consultation, sex offenders have been treated since 1992 and group psychotherapy has been offered to them since 1994. Our first therapeutic models were the North-American behavioural-cognitive therapy and Pithers' relapse prevention model. Behavioural-cognitive theory describes paedophilia as an acquired sexual preference maintained by positive reinforcement. Pithers (1990) considered that relapse only occurs in high-risk situations, and that high-risk situations always come after offence precursors. In North America, relapse prevention consists in helping paedophiles spot their high-risk situations and offence precursors, and enhance their skills to cope with such situations or to prevent them. Therapy programs were developed according to these models, aiming to help offenders develop such skills, ie empathy, social skills, cognitive restructuring, self-esteem, etc. Trying to apply these therapy programs in France, our team quickly realised that we would have to adapt them to French culture. On the one hand, behavioural-cognitive theory did not seem satisfactory enough in explaining paedophilic behaviour and paedophilic preference. On the other hand, behavioural-cognitive therapy made patients into children too much and increased resistance. Therapy based on programs seemed too rigid for French patients and therapists, and we often felt we were working on an issue that would have been much more accurate to work on a few sessions earlier, when this issue was spontaneously brought up by a patient. We believe change occurs all the more as issues are worked on at the right moment for the patient. Moreover, on a cultural point of view, we also realised the use of programs in psychotherapy was difficult to

  9. Radiation therapy for primary central nervous system lymphoma

    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.

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

    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

  11. Auger radiation targeted into DNA: a therapy perspective

    Auger electron emitters that can be targeted into DNA of tumour cells represent an attractive systemic radiation therapy goal. In the situation of DNA-associated decay, the high linear energy transfer (LET) of Auger electrons gives a high relative biological efficacy similar to that of α particles. In contrast to α radiation, however, Auger radiation is of low toxicity when decaying outside the cell nucleus, as in cytoplasm or outside cells during blood transport. The challenge for such therapies is the requirement to target a high percentage of all cancer cells. An overview of Auger radiation therapy approaches of the past decade shows several research directions and various targeting vehicles. The latter include hormones, peptides, halogenated nucleotides, oligonucleotides and internalising antibodies. Here, we will discuss the basic principles of Auger electron therapy as compared with vector-guided α and β radiation. We also review some radioprotection issues and briefly present the main advantages and disadvantages of the different targeting modalities that are under investigation. (orig.)

  12. Phenytoin Induced Erythema Multiforme after Cranial Radiation Therapy.

    Kazanci, Atilla; Tekkök, İsmail Hakkı

    2015-08-01

    The prophylactic use of phenytoin during and after brain surgery and cranial irradiation is a common measure in brain tumor therapy. Phenytoin has been associated with variety of adverse skin reactions including urticaria, erythroderma, erythema multiforme (EM), Stevens-Johnson syndrome, and toxic epidermal necrolysis. EM associated with phenytoin and cranial radiation therapy (EMPACT) is a rare specific entity among patients with brain tumors receiving radiation therapy while on prophylactic anti-convulsive therapy. Herein we report a 41-year-old female patient with left temporal glial tumor who underwent surgery and then received whole brain radiation therapy and chemotherapy. After 24 days of continous prophylactic phenytoin therapy the patient developed minor skin reactions and 2 days later the patient returned with generalized erythamatous and itchy maculopapuler rash involving neck, chest, face, trunk, extremities. There was significant periorbital and perioral edema. Painful mucosal lesions consisting of oral and platal erosions also occurred and prevented oral intake significantly. Phenytoin was discontinued gradually. Systemic admistration of corticosteroids combined with topical usage of steroids for oral lesions resulted in complete resolution of eruptions in 3 weeks. All cutaneous lesions in patients with phenytoin usage with the radiotherapy must be evoluated with suspicion for EM. PMID:26361537

  13. Radiation therapy for advanced laryngeal carcinoma

    From 1967 through 1985, 92 patients with T3 and T4 laryngeal carcinoma were treated with radiation at Osaka University Hospital. Of 92 patients, patients with 14 T3 and 29 T4 carcinoma were treated with a total dose of 60 Gy or more, and those with 14 T3 and 21 T4 carcinoma were treated with a total dose of 40 to 58 Gy and followed by total laryngectomy. Other 14 patients were palliatively treated with a total dose less than 60 Gy without surgery. The 5-year local control rates for T3 and T4 carcinoma treated with radical radiation were 48% and 24%, respectively. The 5-year cause-specific survival rates for T3 carcinoma treated with radical and preoperative radiotherapy were 48% and 71%, and corresponding figures for T4 carcinoma were 52% and 43%. There were no statistically significant differences between cause-specific survival rates of radical and preoperative groups. The 5-year cause-specific survival rates for T3N0 and T4N0 cases treated with radical radiation were 83% and 56%, and corresponding figures for T3N+ and T4N+ cases were 13% and 45%. Voice preservation rates of T3 and T4 patients treated with radical radiation were about 1/2 and 1/4, respectively. Considering the QOL of patients, radiotherapy for advanced carcinoma of larynx should be considered as a primary treatment especially for N0 cases. (author)

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

    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

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

    Salzburger Walter

    2011-04-01

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

  16. The radiation therapy of benign diseases

    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)

  17. Maxillary sinus carcinoma: result of radiation therapy

    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

  18. Cisplatin and derivatives with radiation therapy: for what clinical use?

    Since its discovery by Rosenberg in 1965, cisplatin and its derivatives have appeared as the most important chemotherapeutic agents, particularly for their radiosensitizing properties and their clinical use with radiation. In spite of numerous preclinical and clinical studies, optimal schedules of platin and radiotherapy combination have to be defined. The first part of this overview will describe biological mechanisms of interaction between radiation therapy and platinum derivatives. The second part will report the major clinical impact of their association. (author)

  19. Anonymization of DICOM Electronic Medical Records for Radiation Therapy

    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...

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

    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

  1. Optical tomography for measuring dose distribution in radiation therapy

    Kauppinen Matti

    2014-01-01

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

  2. Conserved sex chromosomes across adaptively radiated Anolis lizards.

    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

  3. Sexual dysfunctions after prostate cancer radiation therapy

    Sexual dysfunctions are a quality of life main concern following prostate cancer treatment. After both radiotherapy and brachytherapy, sexual function declines progressively, the onset of occurrence of erectile dysfunction being 12-18 months after both treatments. The pathophysiological pathways by which radiotherapy and brachytherapy cause erectile dysfunction are multi-factorial, as patient co-morbidities, arterial damage, exposure of neurovascular bundle to high levels of radiation, and radiation dose received by the corpora cavernosa at the crurae of the penis may be important in the aetiology of erectile dysfunction. Diagnosis and treatment of postradiation sexual dysfunctions must integrate pre-therapeutic evaluation and information to provide to the patient and his partner a multidisciplinary sexual medicine management. (authors)

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

    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...... clinical tolerances. CONCLUSIONS: A commercial (60)Co MR-IGRT device can produce highly conformal IMRT treatment plans similar in quality to linac IMRT for a variety of disease sites. Additional work is in progress to evaluate the clinical benefit of other novel features of this MR-IGRT system....

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

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

    2011-02-15

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

  6. Stem cell-based therapies for acute radiation syndrome

    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)

  7. Radiation-induced pseudotumor following therapy for soft tissue sarcoma

    Moore, Lacey F.; Kransdorf, Mark J. [Mayo Clinic, Department of Radiology, Jacksonville, FL (United States); Buskirk, Steven J. [Mayo Clinic, Department of Radiation Oncology, Jacksonville, FL (United States); O' Connor, Mary I. [Mayo Clinic, Department of Orthopedic Surgery, Jacksonville, FL (United States); Menke, David M. [Mayo Clinic, Department of Pathology, Jacksonville, FL (United States)

    2009-06-15

    The purpose of this study was to describe the prevalence and imaging appearance of radiation induced pseudotumors in patients following radiation therapy for extremity soft tissue sarcomas. We retrospectively reviewed the serial magnetic resonance (MR) images of 24 patients following radiation therapy for extremity soft tissue sarcomas. A total of 208 exams were reviewed (mean, 8.7 exams per patient) and included all available studies following the start of radiation therapy. Exams were analyzed for the identification of focal signal abnormalities within the surgical bed suggesting local tumor recurrence. Histopathologic correlation was available in nine patients suspected of having local tumor recurrence. Additional information recorded included patient demographics, tumor type and location, radiation type, and dose. The study group consisted of 12 men and 12 women, having an average age of 63 years (range, 39-88 years). Primary tumors were malignant fibrous histiocytoma (n = 13), leiomyosarcoma (n = 6), liposarcoma (n = 3), synovial sarcoma (n = 1), and extraskeletal chondrosarcoma (n = 1). All lesions were high-grade sarcomas, except for two myxoid liposarcomas. Average patient radiation dose was 5,658 cGy (range, 4,500-8,040 cGy). Average follow-up time was 63 months (range, 3-204 months). Focal signal abnormalities suggesting local recurrence were seen in nine (38%) patients. Three of the nine patients with these signal abnormalities were surgically proven to have radiation-induced pseudotumor. The pseudotumors developed between 11 and 61 months following the initiation of radiation therapy (mean, 38 months), with an average radiation dose of 5,527 cGy (range, 5,040-6,500 cGy). MR imaging demonstrated a relatively ill-defined ovoid focus of abnormal signal and intense heterogeneous enhancement with little or no associated mass effect. MR imaging of radiation-induced pseudotumor typically demonstrates a relatively ill-defined ovoid mass-like focus of intense

  8. Radiation-induced pseudotumor following therapy for soft tissue sarcoma

    The purpose of this study was to describe the prevalence and imaging appearance of radiation induced pseudotumors in patients following radiation therapy for extremity soft tissue sarcomas. We retrospectively reviewed the serial magnetic resonance (MR) images of 24 patients following radiation therapy for extremity soft tissue sarcomas. A total of 208 exams were reviewed (mean, 8.7 exams per patient) and included all available studies following the start of radiation therapy. Exams were analyzed for the identification of focal signal abnormalities within the surgical bed suggesting local tumor recurrence. Histopathologic correlation was available in nine patients suspected of having local tumor recurrence. Additional information recorded included patient demographics, tumor type and location, radiation type, and dose. The study group consisted of 12 men and 12 women, having an average age of 63 years (range, 39-88 years). Primary tumors were malignant fibrous histiocytoma (n = 13), leiomyosarcoma (n = 6), liposarcoma (n = 3), synovial sarcoma (n = 1), and extraskeletal chondrosarcoma (n = 1). All lesions were high-grade sarcomas, except for two myxoid liposarcomas. Average patient radiation dose was 5,658 cGy (range, 4,500-8,040 cGy). Average follow-up time was 63 months (range, 3-204 months). Focal signal abnormalities suggesting local recurrence were seen in nine (38%) patients. Three of the nine patients with these signal abnormalities were surgically proven to have radiation-induced pseudotumor. The pseudotumors developed between 11 and 61 months following the initiation of radiation therapy (mean, 38 months), with an average radiation dose of 5,527 cGy (range, 5,040-6,500 cGy). MR imaging demonstrated a relatively ill-defined ovoid focus of abnormal signal and intense heterogeneous enhancement with little or no associated mass effect. MR imaging of radiation-induced pseudotumor typically demonstrates a relatively ill-defined ovoid mass-like focus of intense

  9. Transformation delay of lymphocytes in patients undergoing radiation therapy

    Two types of assay systems to measure the effect of radiation on immune competence are described. The first, transformation, is measured by blast formation or uptake and incorporation of tritiated thymidine by lymphocytes. This measure is affected by a number of known cell responses to radiation such as division delay and delay in DNA synthesis. The second, called Bactec, is designed to measure lymphocyte metabolic activity. Data gathered on 37 patients with lung cancer show that the Bactec system provides a better index of the patient's immune status before and after radiation therapy

  10. Hypofractionated stereotactic radiation therapy for recurrent glioblastoma: single institutional experience

    Glioblastoma (GBM) is the most common malignant primary brain tumor in adults. Tumor control and survival have improved with the use of radiotherapy (RT) plus concomitant and adjuvant chemotherapy, but the prognosis remain poor. In most cases the recurrence occurs within 7–9 months after primary treatment. Currently, many approaches are available for the salvage treatment of patients with recurrent GBM, including resection, re-irradiation or systemic agents, but no standard of care exists. We analysed a cohort of patients with recurrent GBM treated with frame-less hypofractionated stereotactic radiation therapy with a total dose of 25 Gy in 5 fractions. Of 91 consecutive patients with newly diagnosed GBM treated between 2007 and 2012 with conventional adjuvant chemo-radiation therapy, 15 underwent salvage RT at recurrence. The median time interval between primary RT and salvage RT was 10.8 months (range, 6–54 months). Overall, patients undergoing salvage RT showed a longer survival, with a median survival of 33 vs. 9.9 months (p= 0.00149). Median overall survival (OS) from salvage RT was 9.5 months. No patients demonstrated clinically significant acute morbidity, and all patients were able to complete the prescribed radiation therapy without interruption. Our results suggest that hypofractionated stereotactic radiation therapy is effective and safe in recurrent GBM. However, until prospective randomized trials will confirm these results, the decision for salvage treatment should remain individual and based on a multidisciplinary evaluation of each patient

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

    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

    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. Radiation therapy in the management of patients with mesothelioma

    The results of radiation therapy in the management of 27 patients with malignant mesothelioma were reviewed. Eight patients were treated with a curative intent combining attempted surgical excision of tumor (thoracic in 6 and peritoneal in 2), aggressive radiation therapy, and combination chemotherapy using an adriamycin-containing regimen. One patient achieved a 2-year disease-free inteval followed by recurrence of tumor above the thoracic irradiation field. This patient was retreated with localized irradiation and is disease-free after 5 years of initial diagnosis. One patient has persistent abdominal disease at 18 months; the other 6 patients suffered local recurrence within 8-13 months of initiation of treatment. Radiation therapy was used in 19 other patients who received 29 courses for palliation of dyspnea, superior vena cava syndrome, dysphagia, or neurological symptoms of brain metastasis. A palliation index was used to determine the effectiveness of irradiation and revealed that relief of symptoms was complete or substantial in 5 treatment courses, moderately effective in 6 courses and inadequate in 18 treatment courses. Adequate palliation strongly correlated with a dose at or above 4,000 rad in 4 weeks. The management of patients with mesothelioma requires new and innovative approaches to increase the effectiveness of radiation therapy and minimize the significant potential combined toxicity of pulmonary irradiation and adriamycin

  14. Radiation therapy in the management of patients with mesothelioma

    Gordon, W. Jr.; Antman, K.H.; Greenberger, J.S.; Weichselbaum, R.R.; Chaffey, J.T.

    1982-01-01

    The results of radiation therapy in the management of 27 patients with malignant mesothelioma were reviewed. Eight patients were treated with a curative intent combining attempted surgical excision of tumor (thoracic in 6 and peritoneal in 2), aggressive radiation therapy, and combination chemotherapy using an adriamycin-containing regimen. One patient achieved a 2-year disease-free inteval followed by recurrence of tumor above the thoracic irradiation field. This patient was retreated with localized irradiation and is disease-free after 5 years of initial diagnosis. One patient has persistent abdominal disease at 18 months; the other 6 patients suffered local recurrence within 8-13 months of initiation of treatment. Radiation therapy was used in 19 other patients who received 29 courses for palliation of dyspnea, superior vena cava syndrome, dysphagia, or neurological symptoms of brain metastasis. A palliation index was used to determine the effectiveness of irradiation and revealed that relief of symptoms was complete or substantial in 5 treatment courses, moderately effective in 6 courses and inadequate in 18 treatment courses. Adequate palliation strongly correlated with a dose at or above 4,000 rad in 4 weeks. The management of patients with mesothelioma requires new and innovative approaches to increase the effectiveness of radiation therapy and minimize the significant potential combined toxicity of pulmonary irradiation and adriamycin.

  15. Waiting Lists for Radiation Therapy: A Case Study

    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.

  16. Radiation therapy for portal venous invasion by hepatocellular carcinoma

    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.

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

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

  18. In vivo dosimetry in radiation therapy in Sweden

    A prerequisite for achieving high radiation safety for patients receiving external beam radiation therapy is that the hospitals have a quality assurance program. The program should include include monitoring of the radiation dose given to the patient. Control measurements are performed both at the system level and at the individual level. Control measurement is normally performed using in vivo dosimetry, e.g. a method to measure the radiation dose at the individual level during the actual radiation treatment time. In vivo dosimetry has proven to be an important tool to detect and prevent serious errors in patient treatment. The purpose of this research project was to identify the extent to which vivo dosimetry is used and the methods available for this at Swedish radiation therapy clinics. The authority also wanted to get an overall picture of how hospitals manage results of in vivo dosimetry, and how clinics control radiation dose when using modern treatment techniques. The report reflects the situation in Swedish radiotherapy clinics 2007. The report shows that all hospitals use some form of in vivo dosimetry. The instruments used are mainly diodes and termoluminiscence dosimeters

  19. QA in Radiation Therapy: The RPC Perspective

    Ibbott, G. S.

    2010-11-01

    The Radiological Physics Center (RPC) is charged with assuring the consistent delivery of radiation doses to patients on NCI-sponsored clinical trials. To accomplish this, the RPC conducts annual mailed audits of machine calibration, dosimetry audit visits to institutions, reviews of treatment records, and credentialing procedures requiring the irradiation of anthropomorphic phantoms. Through these measurements, the RPC has gained an understanding of the level of quality assurance practiced in this cohort of institutions, and a database of measurements of beam characteristics of a large number of treatment machines. The results of irradiations of phantoms have yielded insight into the delivery of advanced technology treatment procedures.

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

    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 ...

  1. Ionizing radiation response effects on optical fibers in radiation therapy dosimetry applications

    Radiation effects on optical fibers result in two different effects: accumulated radiation damage resulting in a substantial loss of transmission and transient radiation response in which light is generated in the fiber material itself during exposure to radiation. In various medical applications, optical fibers are often exposed to radiation during certain clinical procedures which makes their radiation response and effect of concern to the medical community. Thus, this effect needs to be studied and quantified in that king of environment. This study involves radiation-resistant fibers and the quantification of their light emission response as a function of dose rate and irradiation field size for photon and electron beams at the various energies used in radiation therapy

  2. Thyroid cancer radioiodine therapy: health service performance and radiation safety

    Greek Atomic Energy Commission collected data related to radioiodine I-131 therapy (RAIT) delivery to differentiated thyroid carcinoma patients, for the period 2003-13, corresponding to 100 % of hospitals at national level. Radiation safety and health service performance outcome indicators were assessed. The numbers of hospitals and nuclear medicine (NM) therapy wards, as well as RAIT annual frequencies, have increased. Geographical inhomogeneous distribution of existing infrastructure is recorded. In some cases, the observed inefficient use of NM therapy wards seems to be due to lack of human resources (e.g. nurses). Regular assessment of appropriate key indicators could serve as a useful tool for radiation safety monitoring and health service performance improvement. (authors)

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

    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

  4. Thyroid cancer radioiodine therapy: health service performance and radiation safety.

    Vogiatzi, S; Liossis, A; Lamprinakou, M

    2015-07-01

    Greek Atomic Energy Commission collected data related to radioiodine I-131 therapy (RAIT) delivery to differentiated thyroid carcinoma patients, for the period 2003-13, corresponding to 100 % of hospitals at national level. Radiation safety and health service performance outcome indicators were assessed. The numbers of hospitals and nuclear medicine (NM) therapy wards, as well as RAIT annual frequencies, have increased. Geographical inhomogeneous distribution of existing infrastructure is recorded. In some cases, the observed inefficient use of NM therapy wards seems to be due to lack of human resources (e.g. nurses). Regular assessment of appropriate key indicators could serve as a useful tool for radiation safety monitoring and health service performance improvement. PMID:25809109

  5. Evaluation of neutron radiation field in carbon ion therapy

    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.

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

    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.

  7. Temporary corneal stem cell dysfunction after radiation therapy

    Radiation therapy can cause corneal and conjuctival abnormalities that sometimes require surgical treatment. Corneal stem cell dysfunction is described, which recovered after the cessation of radiation. Methods - A 44-year-old man developed a corneal epithelial abnormality associated with conjuctival and corneal inflammation following radiation therapy for maxillary cancer. Examination of brush cytology samples showed goblet cells in the upper and lower parts of the cornea, which showed increased fluorescein permeability, and intraepithelial lymphocytes. Impression cytology showed goblet cells in the same part of the cornea. Specular microscopy revealed spindle type epithelial cells. Patient follow up included artificial tears and an antibiotic ophthalmic ointment. The corneal abnormalities resolved after 4 months with improved visual acuity without any surgical intervention, but the disappearance of the palisades of Vogt did not recover at 1 year after radiation. Radiation therapy in this patient caused temporary stem cell dysfunction which resulted in conjunctivalisation in a part of the cornea. Although limbal stem cell function did not fully recover, this rare case suggested that medical options should be considered before surgery. (Author)

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

    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

  9. Patient dosimetry in intravascular radiation therapy

    Percutaneous transluminal coronary angioplasty is a well-accepted method for nonsurgical myocardial revascularization. However, the long-term success of this method is limited by the occurrence of restenosis. Endovascular brachytherapy has been put forward as a means to avoid restenosis. Since this technique involves the placement of a radioactive source in a catheter in the patient's arteries, the possible radiation risk should be considered. In this paper the effective dose of the patient associated with the use of Iridium-192 for IRT treatment has been calculated using Monte Carlo techniques. To put the results into perspective the effective dose form the PTCA procedure was also calculated using the same techniques. Calculations were based on the measurement of DAP (Dose Area Product) for the procedure. We found a mean effective dose of 9 mSv for both the PTCA procedures as for the IRT treatment. Thus leading to the conclusion that, from the perspective of radiation burden, the elimination of one PTCA procedure through the use of IRT is a benefit for the patient. (author)

  10. PET/CT in radiation therapy planning

    Regarding treatment planning in radiotherapy PET offers advantages in terms of tumor delineation and the description of biological processes. To define the real impact of this investigation in radiation treatment planning, following experimental, clinical and cost/benefit analysis are required. FDG-PET has a significant impact on GTV and PTV delineation in lung cancer and can detect lymph node involvement and differentiation of malignant tissue from atelectasis. In high-grade gliomas and meningiomas, methionine-PET helps to define the GTV and differentiate tumor from normal tissue. In head and neck cancer, cervix cancer and prostate cancer the value of FDG-PET for radiation treatment planning is still under investigation. For example, FDG-PET can be superior to CT and MRI in the detection of lymph node metastases in head and neck, unknown primary cancer and differentiation of viable tumor tissue after treatment. Therefore, it could play an important role in GTV definition and sparing of normal tissue. For other entities like gastro-intestinal cancer, lymphomas, sarcoma etc., the data of the literature are yet insufficient. The imaging of hypoxia, cell proliferation, angiogenesis, apoptosis and gene expression leads to the identification of different areas of a biologically heterogeneous tumor mass that can be individually targeted using IMRT. In addition, a biological dose distribution can be generated, the so-called dose painting. However, systematical experimental and clinical trials are necessary to validate this hypothesis. (orig.)

  11. Proton radiation therapy for clivus chordoma

    A 57-year-old male with clival chordoma developed severe hoarseness, dysphagia, and dysphonia 1 month after a second removal of the tumor. Magnetic resonance imaging demonstrated a mass 10 cm in diameter in the region of the middle clivus enhanced inhomogeneously by gadolinium-diethylenetriaminepenta-acetic acid, and a defect in the skull base. There was evidence of compression of the anterior surface of the pons. He received proton irradiation employing a pair of parallel opposed lateral proton beams. The dose aimed at the tumor mass was 75.5 Gy, to the pharyngeal wall less than 38 Gy, and to the anterior portion of the pons less than 30 Gy. Time dose and fractionation factor was calculated at 148. Thirty-one months following treatment, he was free of clinical neurological sequelae. Proton therapy should be considered in treatment planning following initial surgical removal or for inoperable clivus chordoma. (author)

  12. Intensity Modulated Radiation Therapy in Prostate Cancer

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

    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

  14. Clinical trial experience using erythropoietin during radiation therapy

    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.)

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

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

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

    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)

  17. Study on neutron radiation field of carbon ions therapy

    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.

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

    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.)

  19. Sexuality in gynecological patients undergoing radiation therapy treatments

    The gynecology patient undergoing radiation therapy treatments may experience physiological and psychological problems related to sexuality. The needs of this group must be met by the radiation oncology staff by their being informed, interested, and experienced in dealing with sexual problems created by radiation therapy treatments. Opportunities to obtain information and for discussion about how the disease and its treatments will affect sexual functioning must be provided for the patient and partner. It is important to remember that the ability to seek and preserve gratifying sexual function is of great importance to almost all women, regardless of age. The patient may feel much personal distress related to the disease, the treatments, and how they affect the way she feels as a sexual human being. Opportunities must be provided to share the feelings created by the treatment process and trained therapists should be available when intensive sexual counseling is needed

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

    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.

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

    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.

  2. Intensity-Modulated Radiation Therapy for Primary Brain Tumors

    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.

  3. Radiation therapy after breast augmentation or reconstruction

    This paper evaluates the feasibility and cosmetic results of definitive breast irradiation in the presence of a silicone prosthesis. Fourteen patients who presented between 1984 and 1989 with a diagnosis of primary (four patients) or locally recurrent (ten patients) breast cancer and whose augmented or reconstructed breasts were treated with radiation were evaluated for acute and late complications. Silicone gel implants were used in 13 patients and free injected silicone in one patient. The total dose ranged from 4,400 to 6,200 cGy with use of tangential photon fields or an en face electron field by megavoltage equipment. In several cases, electron boost was added to the tumor bed

  4. Quality assurance in radiation therapy: physical aspects

    Svensson, H.

    1984-06-01

    The present status of the quality assurance work regarding the physical aspects in radiation treatment is discussed. In particular, the situation in Europe is surveyed. An analysis of the errors in the delivered absorbed dose to a specified point in the irradiated patient shows that the uncertainty, to approximately the same degree, depends on the dose distribution determination, the dose planning and the patient irradiation. Following the procedure generally in use, the overall uncertainty will be about 8%. The random uncertainties are estimated as one standard deviation and non-random uncertainties to corresponding degree of uncertainty. It is argued that this level must be improved. Furthermore, dose intercomparisons show that in reality much larger errors occur in clinical practice. Different means to improve the situation are discussed.

  5. Stereotactic Body Radiation Therapy in Spinal Metastases

    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.

  6. Radiation effects in the stainless steel primary coolant supply adapter

    Farrell, K.

    1995-09-01

    The primary coolant supply adapter (PCSA) is a flanged, cylindrical collar of 316NG stainless steel that is part of the primary pressure boundary of the Advanced Neutron Source. The radiation fluxes on the PCSA are dominated by thermal neutrons. During its intended 40-year service life, the PCSA will receive a thermal neutron fluence of 1.8 {times} 10{sup 26} m{sup {minus}2} in its upper sections at a temperature of <1OO{degree}C. The PCSA will suffer radiation damage, caused primarily by the interaction of thermal neutrons with the 14% nickel in the steel, which will generate helium by the sequential reactions {sup 58}Ni (n,y){sup 59}Ni (n,{alpha}){sup 56}Fe and will concurrently produce significant atomic displacements per atom (dpa) from the {sup 59}Ni (n,{alpha}){sup 56}Fe recoils. It is estimated that the helium concentration and total atomic displacements in the upper parts of the PCSA will be about 430 atomic parts per million and 1 dpa, respectively. From newly compiled trend curves of tensile properties and fracture toughness data versus atomic displacements for 316 steel, it is deduced that the irradiated PCSA will retain at least 20% uniform tensile elongation and a fracture toughness of more than 200 Mpa{radical}m, which are judged adequate to resist brittle failure. Tberefore, employment of a neutron shield around the PCSA is unnecessary.

  7. Some computer graphical user interfaces in radiation therapy.

    Chow, James C L

    2016-03-28

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

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

    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.

  9. Influence of adaptative response to low dose radiation on radiation-induced thymic lymphoma in mice

    Objective: To search for influence of low dose radiation (LDR) on thymic lymphoma (TL) induced by carcinogenic dose radiation in C57BL /6J mice and its immunologic mechanism. Methods: The model was adopted that C57BL/6J mice were subjected to whole body irradiation with 1.75 Gy X-ray once every week for 4 weeks to induce TL. The incidence of TL was observed by microscopy 6 months after irradiation. The following indexes were examined:splenic NK cytotoxic activity, IL-2 and γ- IFN secretion activity, peritoneal macrophage phagocytosis and its TNFα secretion activity, the changes of thymocyte differentiation in mice irradiated with different dose 1 month after irradiation. Results: The incidences of Tl in mice irradiated with 25mGy or 75m Gy 6h or 12h before 1.75Gy irradiation were all lower than that in mice irradiated with 1.75Gy only, and it is more obvious in mice irradiated with 75mGy prior to carcinogenic dose radiation. Immune parameters mentioned above in mice irradiated with 75mGy 12h before 1.75Gy were higher than those in mice irradiated with 1.75 only and the majority approached to those of the sham-irradiated mice. The number of thymic CD4-CD8 cells or CD4-CD8- cells was lower and CD4+CD 8+ cells was higher in mice irradiated with 75mGy 12h before 1.75Gy than that in mice irradiated with 1.75Gy only. Conclusion: LDR can induce the adaptative response of radiation-induced TL, and prevent or reduce the onset of radiation-induced TL. The suppression mechanism may be related to the immuno-enhancement effect and the adaptive response induced by LDR, decreasing immune function damage caused by carcinogenic dose radiation, eliminating thymic pre-lymphoma cells before they from solid tumor

  10. An integrated ultrasound-computer dosimetry system for radiation therapy

    A highly interactive on-line computer-based radiation therapy planning system has been developed to allow first-hand participation by the physician for maximum input of clinical judgement in treatment planning. The system utilizes an ultrasound scanning device for acquisition of the patient's contour and anatomical information for simultaneous evaluation by the therapist and processing by the computer. The man-machine interaction and graphic data entry are achieved through a sonic graph pen digitizer mounted on the screen of a multi-colour video monitor. A second graph pen digitizer on a radiograph view box is used for digitization and entry to the computer of other graphic data sources. Radiation treatment parameters are graphically entered directly on the echogram of the patient's cross-sectional anatomy. The radiation dose distribution for a proposed plan is then computed and displayed superimposed in a contrasting colour on the echogram for further scrutiny by the therapist and possible modification. When an acceptable plan is produced, the radiation fields are accurately marked on the patient body in reference to the radiation ports displayed. The system is used for external beam planning with simple, multiple, and irregular fields and intracavitary and interstitial implant dosimetry. Since in this system the radiation delivery is planned based on the cross-sectional anatomy, it is well suited for planning of heavy particle beam therapy which utilizes the stopping characteristics of the accelerated particles in the absorbing medium. (author)

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

    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)

  12. Anaemia and radiation therapy; Anemie et radiotherapie

    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)

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

    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.

  14. Pulmonary function tests after radiation therapy following pneumonectomy

    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)

  15. Radiation Induced Rib Fractures on Bone Scan after Breast Cancer Surgery and Radiation Therapy

    Kim, Hae Won; Won, Kyoung Sook; Zeon, Seok Kil; Kim, Jin Hee [Keimyung University, School of Medicine, Daegu (Korea, Republic of)

    2009-08-15

    This study is to evaluate rib fractures on bone scan in breast cancer patients treated with breast cancer surgery and radiation therapy and to evaluate its relation with radiation therapy and operation modality. Two hundred seventy cases that underwent serial bone scan after breast cancer surgery and radiation therapy were enrolled. Bone scan and chest CT findings of rib fracture were analyzed. The rib uptake was seen in 74 of 270 cases (27.4%) on bone scan and 50 cases (18.5%) were confirmed to have rib fracture by chest CT. The rate of modified radical mastectomy in patients with rib fracture was significantly higher than that in patients without rib fracture (66.0% vs. 27.0%, p=0.000). The rate of additional radiation therapy to axillar or supraclavicular regions in patients with rib fracture was significantly higher than that in patients without rib fracture (62.0% vs. 28.6%, p=0.000). Rib fracture was seen most frequently at 1-2 years after radiation therapy (51.9%) and single rib fracture was seen most frequently (55.2%). Of total 106 rib fractures, focal rib uptake was seen in 94 ribs (88.7%) and diffuse rib uptake was seen in 12 ribs (11.3%). On one year follow-up bone scan, complete resolution of rib uptake was seen in 15 ribs (14.2%). On chest CT, the rate of fracture line in ribs with intense uptake was significantly higher than that in ribs with mild or moderate uptake (p=0.000). The rate of presence of fracture line in ribs with focal uptake was significantly higher than that in ribs with diffuse uptake (p=0.001). Rib fracture in breast cancer patients after radiation therapy was related to radiation portal and operation modality. It should be interpreted carefully as a differential diagnosis of bone metastasis.

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

    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.

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

    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

  18. Radiation therapy in early Glotic cancer

    Early vocal cord carcinomas (TiS or T1) in a cosecutive series of 177 patients treaded by primary radiotherapy over a 10-year period 1970-79 were analysed regarding treatment results. In 137 cases the tumours were invasive (T1N0M0) and in 40 cases carcinoma of in situ type (TiS). Patient were treated with cobalt 60 gamma radiation in fraction of 2 Gy up to a total dose of 64 Gy delivered as split course. Minimum follow-up time was 5 years. Tumour recurred in 21 cases (12%). All but 4 patients were rescued by subsequent surgery, giving 98% total survival. Treatment failures after primary radiotherapy were analysed in detail. Failures could not be attributed to treatment irregularities. No difference in pretreatment tomour size was detected when cured patients were compared with patients who relapsed. Biological factors that cause a relative radioresistance are considered to be the main reson for radiotherapy failures in early glottic cancer

  19. Radiation exposure in I-131 iodine therapy

    In the past five years, the applied I-131 radioactivity quantity has doubled with a constant number of beds. In 1984, it was 925 GBq (25 Ci). Despite this development, no changes in the professional radiation exposure were made out. The evaluation shows a dose smaller than 0.04 man Sv/TBq (0.16 man rem/Ci) of I-131 applied. This value is below the traceability limit of the film badges. The incorporation load of the personnel (27 members) was determined by monthly body counter measurements. Only in one measurement thyroid gland activity of 5 kBq (140 nCi) was detected. Most measurements did not show any incorporation; and the few positive results were below 0.74 kBq (20 nCi). The environmental load due to unfiltered release from patients' rooms was determined at the fence of the nuclear research plant. The maximum was 0.24 mSv/a thyroid gland dose of a small child in 1982 taking into account the measured 90% partion of organic compound iodine. The waste water is decayed following chemical treatment in storage tanks. (orig./HP)

  20. Late neuro endocrinological sequelae of radiation therapy

    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)

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

    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

  2. Recent London improvements in curative radiation therapy for relevant early prostate cancer.

    Plowman, P N

    2008-09-01

    Since the advent of PSA screening, the detection of early (organ confined) prostate cancer has improved. Although some indolent cancers in the elderly may be safely watched, the early diagnosis in younger men requires curative treatment. Two exciting modernized radiation therapy methods provide alternatives to major surgery and lead to cure rates equivalent to surgery. Modern intensity modulated external beam radiotherapy (IMRT) allows high-dose treatment to the prostate (+/- seminal vesicles) while maximally sparing the rectum (due to the extraordinary capability of creating a concavity in a high-dose radiation therapy volume). This has allowed escalation in the therapy dose to the prostate and improved cure rates. We have recently compared two different IMRT methods. Our introduction of "axial limits" rectal definition allows more accurate quantitation of relevant rectal sparing. Prostate radiation seed brachytherapy (Seattle 125-iodine method) provides a sophisticated, single-session radiation therapy method that has become the most popular curative method by busy men who want minimum interruption to their lives. The implant is "tailored" for the individual's gland size and shape, and in the London adaptation of the method there is interoperative monitoring of seed implantation, such that if any seed is slightly misplaced the information of deposition site is relayed back to a computer, which reconfigures the deposition of all subsequent seeds such that an ideal plan is achieved-dynamic, iterative, computer assisted implantation. The popularity of these two radiation techniques is largely due to the lesser rate of morbidity compared to surgery and the usual fast return to everyday life. PMID:18837905

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

    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.

  4. Stereotactic radiation therapy for progressive residual pilocytic astrocytomas.

    Lizarraga, Karlo J; Gorgulho, Alessandra; Lee, Steve P; Rauscher, Glenn; Selch, Michael T; DeSalles, Antonio A F

    2012-08-01

    This report shows the results of stereotactic radiation therapy for progressive residual pilocytic astrocytomas. Medical records of patients who had undergone stereotactic radiation therapy for a progressive residual pilocytic astrocytoma were reviewed. Between 1995 and 2010, 12 patients with progression of a residual pilocytic astrocytoma underwent stereotactic radiation therapy at UCLA. Presentation was headache (4), visual defects (3), hormonal disturbances (2), gelastic seizures (2) and ataxia (1). MRI showed a cystic (9), mixed solid/cystic (2) or solid tumor (1); located in the hypothalamus (5), midbrain (3), thalamus (2), optic chiasm (1) or deep cerebellum (1). Median age was 21 years (range 5-41). Nine tumors received stereotactic radiotherapy (SRT). Three tumors received stereotactic radiosurgery (SRS), two of them to their choline positive regions. SRT median total dose was 50.4 Gy (40-50.4 Gy) in a median of 28 fractions (20-28), using a median fraction dose of 1.8 Gy (1.8-2 Gy) to a median target volume of 6.5 cm(3). (2.4-33.57 cm(3)) SRS median dose was 18.75 Gy (16.66-20 Gy) to a median target volume of 1.69 cm(3) (0.74-2.22 cm(3)). Median follow-up time was 37.5 months. Actuarial long-term progression-free and disease-specific survival probabilities were 73.3 and 91.7 %, respectively. No radiation-induced complications were observed. Stereotactic radiation therapy is a safe and effective modality to control progressive residual pilocytic astrocytomas. Better outcomes are obtained with SRT to entire tumor volumes than with SRS targeting choline positive tumor regions. PMID:22644536

  5. Orthovoltage intraoperative radiation therapy for pancreatic adenocarcinoma

    Kapp Daniel S

    2010-11-01

    Full Text Available Abstract Purpose To analyze the outcomes of patients from a single institution treated with surgery and orthovoltage intraoperative radiotherapy (IORT for pancreatic adenocarcinoma. Methods We retrospectively reviewed 23 consecutive patients from 1990-2001 treated with IORT to 23 discrete sites with median and mean follow up of 6.5 and 21 months, respectively. Most tumors were located in the head of the pancreas (83% and sites irradiated included: tumor bed (57%, vessels (26%, both the tumor bed/vessels (13% and other (4%. The majority of patients (83% had IORT at the time of their definitive surgery. Three patients had preoperative chemoradiation (13%. Orthovoltage X-rays (200-250 kVp were employed via individually sized and beveled cone applicators. Additional mean clinical characteristics include: age 64 (range 41-81; tumor size 4 cm (range 1.4-11; and IORT dose 1106 cGy (range 600-1500. Post-operative external beam radiation (EBRT or chemotherapy was given to 65% and 76% of the assessable patients, respectively. Outcomes measured were infield control (IFC, loco-regional control (LRC, distant metastasis free survival (DMFS, overall survival (OS and treatment-related complications. Results Kaplan-Meier (KM 2-year IFC, LRC, DMFS and OS probabilities for the whole group were 83%, 61%, 26%, and 27%, respectively. Our cohort had three grade 3-5 complications associated with treatment (surgery and IORT. Conclusions Orthovoltage IORT following tumor reductive surgery is reasonably well tolerated and seems to confer in-field control in carefully selected patients. However, distant metastases remain the major problem for patients with pancreatic adenocarcinoma.

  6. Neurovisual outcome following proton radiation therapy

    From February 1981 to January 1984, 20 patients with a tumor of the upper clivus received proton irradiation at the Harvard Cyclotron Laboratory. For 15 patients with known neurovisual status (including visual acuity, color vision, visual field, and fundus examinations) we obtained a cumulative dose-volume histogram (DVH) of the optic nerves (ON) and the optic chiasm. The prescribed tumor doses ranged from 66.6 to 74.4 Cobalt Gray Equivalent (CGE) with a daily fraction size of 1.8 to 2.1 CGE. CGE is used because modulated protons have an RBE of 1.1 compared to 60Co. The follow-up ranged from 30 to 68 months (median 52). Two patients developed, 10 and 36 months post irradiation, a progressive visual deterioration affecting both eyes. This was attributed to an ON and a chiasm injury in one patient and to bilateral ON injury in the other patient. In the first patient, the dose-volume analysis indicated that approximately half of the ON and of the chiasm had received 65 CGE and 55 CGE, respectively. In the second patient, it indicated that a quarter of the left ON (LON) had received 55 CGE whereas the dose to the right ON (RON) was significantly less. This patient had diabetes mellitus which may be a predisposing factor. From this study, a complication rate of 20% (1/5) is observed when a substantial portion of the ON is taken to 65 CGE, while it doesn't exceed 12.5% (2/16) and 7.5% (1/13) at 55 CGE for the ON and for the chiasm, respectively. This suggests a tolerance dose implying a 10% rate of major complications close to 55 CGE. When a tumor requires a high radiation-dose, the exclusion of these structures at 55 to 60 Gy is recommended

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

    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

  8. Adapted Behavior Therapy for Persistently Depressed Primary Care Patients: An Open Trial

    Uebelacker, Lisa A.; Weisberg, Risa B.; Haggarty, Ryan; Miller, Ivan W.

    2009-01-01

    Major depressive disorder is commonly treated in primary care settings. Psychotherapy occurring in primary care should take advantage of the unique aspects of the setting and must adapt to the problems and limitations of the setting. In this open trial, the authors used a treatment development model to adapt behavior therapy for primary care…

  9. The potential of proton beam radiation therapy in breast cancer

    A group of Swedish oncologists and hospital physicists have estimated the number of patients in Sweden suitable for proton beam therapy. The estimations have been based on current statistics of tumour incidence, number of patients potentially eligible for radiation treatment, scientific support from clinical trials and model dose planning studies and knowledge of the dose-response relations of different tumours and normal tissues. In primary breast cancer, it is estimated that about 300 of the annually 3,425 irradiated patients can potentially be candidates for proton beam therapy to reduce late toxicity, mainly from the heart and lungs

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

    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.

  11. Accounting for radiation quality in heavy ion therapy

    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.)

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

    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…

  13. Delayed damage after radiation therapy for head and neck cancer

    I investigated radiation damage, including osteoradionecrosis, arising from tooth extraction in fields that had received radiation therapy for head and neck cancer, and evaluated the effectiveness of pilocarpine for xerostomia. Between January 1990 and April 1996, I examined 30 patients for bone changes after tooth extraction in fields irradiated at the Department of Oral Radiology, Osaka Dental University Hospital. Nineteen of the patients had been treated for nasopharyngeal cancer and 11 for oropharyngeal cancer. Between January and April 1996, 4 additional patients were given pilocarpine hydrochloride (3-mg, 6-mg and 9-mg of KSS-694 orally three times a day) for 12 weeks and evaluated every 4 weeks as a base line. One had been treated for nasopharyngeal carcinoma, two for cancer of the cheek and one for an unknown carcinoma. Eighteen of the patients (11 with nasopharyngeal carcinoma and 7 with oropharyngeal carcinoma) had extractions. Use of preoperative and postoperative radiographs indicated that damage to the bone following tooth extraction after radiation exposure was related to whether antibiotics were administered the day before the extraction, whether forceps or elevators were used, and whether the tooth was in the field of radiation. Xerostomia improved in all 4 of the patients who received 6-mg or 9-mg of pilocarpine. It improved saliva production and relieved the symptoms of xerostomia after radiation therapy for head and neck cancer, although there were minor side effects such as fever. This information can be used to improve the oral environment of patients who have received radiation therapy for head and neck cancer, and to better understand their oral environment. (author)

  14. Gold Nanoparticles and Their Alternatives for Radiation Therapy Enhancement

    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.

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

    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...

  16. [Hyperbaric oxygen therapy and radiation-induced hemorrhagic cystitis].

    Pires, Christophe; Irani, Jacques; Ouaki, Frédéric; Murat, François-Joseph; Doré, Bertrand

    2002-12-01

    Radiotherapy alone or in combination with other modalities is used in the treatment of a large number of pelvic tumours of urological or gynaecological origin. Despite constant progress in this field, medium-term and long-term complications remain frequent and often require difficult long-term management. Radiation cystitis is one of the most frequent complications and directly concerns urologists. Among the various treatment options for haemorrhagic cystitis, hyperbaric oxygen therapy appears to give good short-term and medium-term results. It is currently reserved for cases refractory to the standard treatments for radiation cystitis. PMID:12545623

  17. Cardiovascular radiation therapy - a multi-disciplinary textbook

    The textbook is the first of its kind in the German language that presents an exhaustive survey of the state-of-the-art in cardiovascular radiation therapy at international level. The contributions explain the causes of restenosis, the fundamental aspects and principles as well as the current practice in radiation treatment intended to improve the long-term effects of PTCA, and present initial results of clinical studies. Specialists from various branches of medicine contributed their specific experimental and clinical findings. (orig./CB)

  18. Role of radiation therapy in the treatment of parotid carcinomas

    Radiation therapy appears to be useful in postoperative management of patients with parotid gland tumors. Because the local recurrence rate is excessive, postoperative irradiation should be routinely considered for high grade mucoepidermoid carcinomas, all squamous cell, adeno- and undifferentiated carcinomas of the parotid. Doses should be at least equivalent to 6500 rads in 6 weeks to 4 cm. depth (or measured tumor depth). The radiation fields should cover the base of skull and lower neck to prevent extension of the cancer. (U.S.)

  19. Radiation shielding design calculation of gamma knife for therapy

    The author reports the method and results of radiation shielding calculation of the gamma knife for therapy which is composed of thirty 60Co sources each with 7.4 EBq, semi-spherical shield, lateral shielding cupboard and the shielding door. The shielding thicknesses of the back shield, the lateral shielding cupboard and the shielding door were calculated. The leakage radiation by test indicates that the shielding is sufficient safety for this Gamma knife and the Kerma rate of control calculated agrees with that by test

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

    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

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

    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...

  2. In-room CT techniques for image-guided radiation therapy

    Accurate patient setup and target localization are essential to advanced radiation therapy treatment. Significant improvement has been made recently with the development of image-guided radiation therapy, in which image guidance facilitates short treatment course and high dose per fraction radiotherapy, aiming at improving tumor control and quality of life. Many imaging modalities are being investigated, including x-ray computed tomography (CT), ultrasound imaging, positron emission tomography, magnetic resonant imaging, magnetic resonant spectroscopic imaging, and kV/MV imaging with flat panel detectors. These developments provide unique imaging techniques and methods for patient setup and target localization. Some of them are different; some are complementary. This paper reviews the currently available kV x-ray CT systems used in the radiation treatment room, with a focus on the CT-on-rails systems, which are diagnostic CT scanners moving on rails installed in the treatment room. We will describe the system hardware including configurations, specifications, operation principles, and functionality. We will review software development for image fusion, structure recognition, deformation correction, target localization, and alignment. Issues related to the clinical implementation of in-room CT techniques in routine procedures are discussed, including acceptance testing and quality assurance. Clinical applications of the in-room CT systems for patient setup, target localization, and adaptive therapy are also reviewed for advanced radiotherapy treatments

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

    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

  4. Radiation therapy for carcinoma of the major salivary glands

    From January 1967 through November 1991, a total of 135 patients with carcinoma of the major salivary glands (parotid: 95; submandibular: 39, sublingual: 1) were treated at our department. 40 patients had adenocarcinoma, 29 adenoid cystic carcinoma, 24 mucoepidermoid carcinoma and 16 squamous cell carcinoma. 100 patients were irradiated postoperatively and the remaining 35 were treated with radiation alone. Total radiation doses delivered were 50 Gy for the postoperative group and 50 to 66 Gy for the group receiving only radiation using a 60Co single portal with or without wedged paired or single electron portal boost. Actuarial five-year survivals after radiation therapy were 55% for the postoperative group and 26% for radiation only group (p=0.0004). The local control rates for the postoperative group were 83% for adenocarcinoma, 81% for adenoid cystic carcinoma, 83% for mucoepidermoid carcinoma and 62% for squamous cell carcinoma. Corresponding figures for the radiation only group were 40% for adenocarcinoma, 38% for adenoid cystic carcinoma and 33% for mucoepidermoid carcinoma. Conventional irradiation techniques continue to play an important role because they offer superior local control for postoperative patients with carcinoma of the major salivary glands. However, the local control rates for the radiation only group were only 30 to 40%, so that new irradiation modalities such as provided by a high LET machine are needed for these patients. (orig.)

  5. Radiation therapy for carcinoma of the major salivary glands

    Teshima, T. (Dept. of Radiology, Osaka Univ. Medical School (Japan)); Inoue, Ta. (Dept. of Radiology, Osaka Univ. Medical School (Japan)); Inoue, To. (Dept. of Radiation Oncology, Osaka Univ. Medical School (Japan)); Ikeda, H. (Dept. of Radiation Oncology, Osaka Univ. Medical School (Japan)); Yamazaki, H. (Dept. of Radiation Oncology, Osaka Univ. Medical School (Japan)); Ohtani, M. (Dept. of Radiology, Osaka Univ. Medical School (Japan)); Shimizutani, K. (Dept. of Radiology, Osaka Univ. Medical School (Japan)); Furukawa, S. (Dept. of Radiology, Osaka Univ. Medical School (Japan)); Kozuka, T. (Dept. of Radiology, Osaka Univ. Medical School (Japan)); Murayama, S. (National Inst. of Radiological Science, Chiba (Japan))

    1993-08-01

    From January 1967 through November 1991, a total of 135 patients with carcinoma of the major salivary glands (parotid: 95; submandibular: 39, sublingual: 1) were treated at our department. 40 patients had adenocarcinoma, 29 adenoid cystic carcinoma, 24 mucoepidermoid carcinoma and 16 squamous cell carcinoma. 100 patients were irradiated postoperatively and the remaining 35 were treated with radiation alone. Total radiation doses delivered were 50 Gy for the postoperative group and 50 to 66 Gy for the group receiving only radiation using a [sup 60]Co single portal with or without wedged paired or single electron portal boost. Actuarial five-year survivals after radiation therapy were 55% for the postoperative group and 26% for radiation only group (p=0.0004). The local control rates for the postoperative group were 83% for adenocarcinoma, 81% for adenoid cystic carcinoma, 83% for mucoepidermoid carcinoma and 62% for squamous cell carcinoma. Corresponding figures for the radiation only group were 40% for adenocarcinoma, 38% for adenoid cystic carcinoma and 33% for mucoepidermoid carcinoma. Conventional irradiation techniques continue to play an important role because they offer superior local control for postoperative patients with carcinoma of the major salivary glands. However, the local control rates for the radiation only group were only 30 to 40%, so that new irradiation modalities such as provided by a high LET machine are needed for these patients. (orig.)

  6. BGRT: Biologically guided radiation therapy - The future is fast approaching!

    Rapid advances in functional and biological imaging, predictive assays, and our understanding of the molecular and cellular responses underpinning treatment outcomes herald the coming of the long-sought goal of implementing patient-specific biologically guided radiation therapy (BGRT) in the clinic. Biological imaging and predictive assays have the potential to provide patient-specific, three-dimensional information to characterize the radiation response characteristics of tumor and normal structures. Within the next decade, it will be possible to combine such information with advanced delivery technologies to design and deliver biologically conformed, individualized therapies in the clinic. The full implementation of BGRT in the clinic will require new technologies and additional research. However, even the partial implementation of BGRT treatment planning may have the potential to substantially impact clinical outcomes

  7. Primary radiation therapy in the management of glomus tumours

    The records of five patients who received local irradiation for incompletely excised or inoperable glomus tumour were retrospectively reviewed. Age ranged from 25 to 46 years. There were two female and three male patients. Two patients who were solely treated by radiation therapy remain clinically disease free at 30 and 42 months respectively. Of the remaining three patients, where radiotherapy was delivered post operatively, one achieved complete remission and is well and alive at 60 months, whereas the other two patients were lost to follow up at 22 and 26 months respectively after showing an early clinical improvement. We advocate the efficiency of radiation therapy as primary treatment in the management of primary glomus tumour. (author). 14 refs., 2 tabs

  8. Conformal radiation therapy: technical requirements and clinical applications

    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

  9. Neutron radiation area monitoring system for proton therapy facilities

    A neutron radiation area monitoring system has been developed for proton accelerator facilities dedicated to cancer therapy. The system comprises commercial measurement equipment, computer hardware and a suite of software applications that were developed specifically for use in a medical accelerator environment. The system is designed to record and display the neutron dose-equivalent readings from 16 to 24 locations (depending on the size of the proton therapy centre) throughout the facility. Additional software applications provide for convenient data analysis, plotting, radiation protection reporting, and system maintenance and administration tasks. The system performs with a mean time between failures of >6 months. Required data storage capabilities and application execution times are met with inexpensive off-the-shelf computer hardware. (authors)

  10. Impact of dose calculation algorithm on radiation therapy

    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.

  11. Old but new methods in radiation oncology. Hyperbaric oxygen therapy

    The presence of hypoxic tumor cells is widely regarded as one of the main reasons behind the failure to control malignant tumors with radiotherapy treatments. Since hyperbaric oxygenation (HBO) improves the oxygen supply to the hypoxic tumor cells, HBO therapy has previously been used in combination with simultaneous radiotherapy to treat malignant tumors. In some clinical trials, significant improvements in local control and survival have been seen in cancers of the head and neck and the uterine cervix. However, the delivery of simultaneous HBO therapy and radiotherapy is both complex and time-consuming, with some trials reporting increased side effects. As a result, the regimen of HBO therapy in combination with simultaneous radiotherapy has yet to be used as a standard treatment for malignant tumors. In recent years, however, radiotherapy immediately after HBO therapy has been emerging as an attractive approach for overcoming hypoxia in cancer treatment. Several studies have reported that radiotherapy immediately after HBO therapy was safe and seemed to be effective in patients with high-grade gliomas. Also, this approach may protect normal tissues from radiation injury. To accurately estimate whether the delivery of radiotherapy immediately after HBO therapy can be beneficial in patients with high-grade gliomas and other cancers, further prospective studies are warranted. (author)

  12. Radiation therapy of lymphoblastic renal masses - benefit or hazard

    A child with non-Hodgkin lymphoma and massively enlarged kidneys received a single dose of 300 rad (3 Gy) to the right kidney before initiation of chemotherapy. Measurement of the split renal function with 99m-Tc-DTPA four days postirradiation revealed that the function of the right kidney had substantially deteriorated, suggesting that hazards may be involved with the use of radiation therapy for lymphoblastic renal masses

  13. Urethral strictures after radiation therapy for prostate cancer

    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.

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

    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

  15. 4D PET-CT guided radiation therapy

    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.

  16. ReVOLT: radiation-enhanced viral oncolytic therapy

    Viral oncolytic therapy has been pursued with renewed interest as the molecular basis of carcinogenesis and viral replication has been elucidated. Genetically engineered, attenuated viruses have been rationally constructed to achieve a therapeutic index in tumor cells compared with surrounding normal tissue. Many of these attenuated mutant viruses have entered clinical trials. Here we review the preclinical literature demonstrating the interaction of oncolytic viruses with ionizing radiation and provides a basis for future clinical trials

  17. Radiation therapy of tumours of the central nervous system

    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)

  18. ROENTGEN: case-based reasoning and radiation therapy planning.

    Berger, J.

    1992-01-01

    ROENTGEN is a design assistant for radiation therapy planning which uses case-based reasoning, an artificial intelligence technique. It learns both from specific problem-solving experiences and from direct instruction from the user. The first sort of learning is the normal case-based method of storing problem solutions so that they can be reused. The second sort is necessary because ROENTGEN does not, initially, have an internal model of the physics of its problem domain. This dependence on e...

  19. Stereotactic Body Radiation Therapy for Treatment of Spinal Bone Metastasis.

    Cihan, Yasemin Benderli

    2016-01-01

    Stereotactic body radiation therapy (SBRT) appears an effective and safe treatment modality for spinal bone metastasis, which can enhance local control and improve quality of life. Life expectation, predicted fracture risk, localization, quality, size and number of metastasis and presence or absence of nerve compression seem to be important factors in decision-making for treatment. Further studies are needed to identify subsets of patient which will most benefit from treatment. PMID:27039816

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

    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...

  1. Technological Advancements and Error Rates in Radiation Therapy Delivery

    Purpose: Technological advances in radiation therapy (RT) delivery have the potential to reduce errors via increased automation and built-in quality assurance (QA) safeguards, yet may also introduce new types of errors. Intensity-modulated RT (IMRT) is an increasingly used technology that is more technically complex than three-dimensional (3D)–conformal RT and conventional RT. We determined the rate of reported errors in RT delivery among IMRT and 3D/conventional RT treatments and characterized the errors associated with the respective techniques to improve existing QA processes. Methods and Materials: All errors in external beam RT delivery were prospectively recorded via a nonpunitive error-reporting system at Brigham and Women’s Hospital/Dana Farber Cancer Institute. Errors are defined as any unplanned deviation from the intended RT treatment and are reviewed during monthly departmental quality improvement meetings. We analyzed all reported errors since the routine use of IMRT in our department, from January 2004 to July 2009. Fisher’s exact test was used to determine the association between treatment technique (IMRT vs. 3D/conventional) and specific error types. Effect estimates were computed using logistic regression. Results: There were 155 errors in RT delivery among 241,546 fractions (0.06%), and none were clinically significant. IMRT was commonly associated with errors in machine parameters (nine of 19 errors) and data entry and interpretation (six of 19 errors). IMRT was associated with a lower rate of reported errors compared with 3D/conventional RT (0.03% vs. 0.07%, p = 0.001) and specifically fewer accessory errors (odds ratio, 0.11; 95% confidence interval, 0.01–0.78) and setup errors (odds ratio, 0.24; 95% confidence interval, 0.08–0.79). Conclusions: The rate of errors in RT delivery is low. The types of errors differ significantly between IMRT and 3D/conventional RT, suggesting that QA processes must be uniquely adapted for each technique

  2. Technological Advancements and Error Rates in Radiation Therapy Delivery

    Margalit, Danielle N., E-mail: dmargalit@partners.org [Harvard Radiation Oncology Program, Boston, MA (United States); Harvard Cancer Consortium and Brigham and Women' s Hospital/Dana Farber Cancer Institute, Boston, MA (United States); Chen, Yu-Hui; Catalano, Paul J.; Heckman, Kenneth; Vivenzio, Todd; Nissen, Kristopher; Wolfsberger, Luciant D.; Cormack, Robert A.; Mauch, Peter; Ng, Andrea K. [Harvard Cancer Consortium and Brigham and Women' s Hospital/Dana Farber Cancer Institute, Boston, MA (United States)

    2011-11-15

    Purpose: Technological advances in radiation therapy (RT) delivery have the potential to reduce errors via increased automation and built-in quality assurance (QA) safeguards, yet may also introduce new types of errors. Intensity-modulated RT (IMRT) is an increasingly used technology that is more technically complex than three-dimensional (3D)-conformal RT and conventional RT. We determined the rate of reported errors in RT delivery among IMRT and 3D/conventional RT treatments and characterized the errors associated with the respective techniques to improve existing QA processes. Methods and Materials: All errors in external beam RT delivery were prospectively recorded via a nonpunitive error-reporting system at Brigham and Women's Hospital/Dana Farber Cancer Institute. Errors are defined as any unplanned deviation from the intended RT treatment and are reviewed during monthly departmental quality improvement meetings. We analyzed all reported errors since the routine use of IMRT in our department, from January 2004 to July 2009. Fisher's exact test was used to determine the association between treatment technique (IMRT vs. 3D/conventional) and specific error types. Effect estimates were computed using logistic regression. Results: There were 155 errors in RT delivery among 241,546 fractions (0.06%), and none were clinically significant. IMRT was commonly associated with errors in machine parameters (nine of 19 errors) and data entry and interpretation (six of 19 errors). IMRT was associated with a lower rate of reported errors compared with 3D/conventional RT (0.03% vs. 0.07%, p = 0.001) and specifically fewer accessory errors (odds ratio, 0.11; 95% confidence interval, 0.01-0.78) and setup errors (odds ratio, 0.24; 95% confidence interval, 0.08-0.79). Conclusions: The rate of errors in RT delivery is low. The types of errors differ significantly between IMRT and 3D/conventional RT, suggesting that QA processes must be uniquely adapted for each technique

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

    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

  4. The use of recombination chambers at radiation therapy facilities

    Zielczynski, Mieczyslaw [Institute of Atomic Energy, 05-400 Swierk (Poland); Golnik, Natalia, E-mail: golnik@mchtr.pw.edu.p [Institute of Metrology and Biomedical Engineering, Warsaw University of Technology, Sw. A. Boboli 8, 02-525 Warsaw (Poland); Gryzinski, Michal A. [Institute of Atomic Energy, 05-400 Swierk (Poland); Tulik, Piotr [Institute of Atomic Energy, 05-400 Swierk (Poland); Institute of Metrology and Biomedical Engineering, Warsaw University of Technology, Sw. A. Boboli 8, 02-525 Warsaw (Poland)

    2010-12-15

    The paper presents an overview of the applications of recombination chambers for dosimetric measurements at radiotherapy facilities. The chambers were used at electron, proton and heavy ion accelerators, in the beam and in the vicinity of the accelerators at very different dose rates. The examples of measurements discussed in the paper include: the determination of the absorbed dose and radiation quality parameters of a 170 MeV proton beam and BNCT (boron neutron capture therapy) beam, neutron dose measurements at a phantom surface outside the beam of a 15 MV electron medical accelerator, determination of ambient dose equivalent, H* (10) outside the irradiated phantom in the proton therapy treatment room at JINR (Dubna, Russia), and at working places outside the shielding of the heavy ion therapy facility at GSI (Darmstadt, Germany).

  5. The use of recombination chambers at radiation therapy facilities

    The paper presents an overview of the applications of recombination chambers for dosimetric measurements at radiotherapy facilities. The chambers were used at electron, proton and heavy ion accelerators, in the beam and in the vicinity of the accelerators at very different dose rates. The examples of measurements discussed in the paper include: the determination of the absorbed dose and radiation quality parameters of a 170 MeV proton beam and BNCT (boron neutron capture therapy) beam, neutron dose measurements at a phantom surface outside the beam of a 15 MV electron medical accelerator, determination of ambient dose equivalent, H* (10) outside the irradiated phantom in the proton therapy treatment room at JINR (Dubna, Russia), and at working places outside the shielding of the heavy ion therapy facility at GSI (Darmstadt, Germany).

  6. Radiation Therapy in Malignant Tumors of the Parotid Gland

    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.

  7. Radiation Therapy in Malignant Tumors of the Parotid Gland

    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

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

    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

  9. Hyperbaric oxygen therapy for radiation-induced hemorrhagic cystitis

    Hyperbaric oxygen (HBO) therapy has recently emerged as a potential primary option for the management of hemorrhagic cystitis. We review our experience treating hemorrhagic cystitis with HBO. Between January 2001 and May 2007, eight patients with radiation-induced hemorrhagic cystitis underwent HBO therapy. There were five men and three women with a mean age of 64.3 years (47-73). Radiation was given for local disease, and the mean dosage delivered was 56.6 Gy (42-70). The mean duration between the onset of hematuria and the beginning of HBO therapy was 8.9 months (3-34). Mean follow-up period was 15.5 months (2-31). Hematuria resolved completely in six of the eight patients, one of whom suffered recurrence of hematuria and was treated with HBO until the hematuria resolved again. The response rate was 75%, compatible with the previous reports, and no side-effects of HBO were noted. HBO treatment should be attempted for radiation-induced hemorrhagic cystitis. (author)

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

    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

  11. Prophylaxis of heterotopic ossification: preoperative radiation therapy of elbow arthrolysis

    Objective: To assess the efficacy and side -effect of preoperative radiation therapy with 7-8 Gy in patients receiving elbow arthrolysis. Methods: Thirty-two patients with heterotopic ossification (HO) history at elbow were studied. Radiation therapy was given in 1 fraction of 7-8 Gy in 31 patients within 1-4 h before operation, and 2 fractions of 12 Gy in l patient (1 fraction of 8 Gy within 1-4 h before operation and 1 fraction of 4 Gy on the 6th day after operation). Three cases took NSAIDS for a short time after operation. The elbow HO classification at baseline and last follow-up were analyzed. Results: Median follow up was 28.25 months (range: 12-38.5 months). X-ray films showed that 7 (21.9%) patients developed new HO. Four (12.5%) developed into clinical HO with function failure. The elbow function of 19 (59.4%) cases became normal. All cases had no side effect but one had bony nonunion. The Graham and Hastings HO classification scores were significantly different between pre-operation and last follow-up (Z- 4.198, P<0.01). Conclusions: Preoperative radiation therapy of 7-8 Gy within 1-4 h of elbow arthrolysis is safe and effective. (authors)

  12. Adaptive response induced by occupational exposures to ionizing radiation

    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)

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

    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)

    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. Brachytherapy with an improved MammoSite Radiation Therapy System

    Karthik, Nanda; Keppel, Cynthia; Nazaryan, Vahagn

    2007-03-01

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

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

    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.

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

    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

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

    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

  19. Radiation therapy for age-related macular degeneration (ARMD)

    Authors' results of low dose radiation therapy for ARMD were described. CT scan simulation was performed to determine the irradiation field of posterior pole of eyeball to which more than 90% of radiation was to be absorbed. The photon beam of 6MV was irradiated as to avoid lens at 2 Gy/day for 1 or 2 weeks to attain 10 or 20 Gy in total, respectively. After the treatment, the process was followed every 3 months and examinations with fluorescence contrasting, for visual field and for adverse radiation effects were done every 6 months. Results of reduction, no change and increase of choroidal neovascularization plate within 1 y were seen in 7 (47%), 4 (27%) and 4 eyes (27%) per total 15 eyes, respectively, in the treated group with 10 Gy whereas those in the control untreated group were 1 (6%), 6 (35%) and 10 (59%) eyes per 17 eyes, respectively (P<0.05). In addition, the treatment was effective for improvement of serous abruption and of retinal edema and for keeping optesthesia. The radiation therapy with 20 Gy was one too recently introduced to give enough results but may be more promising. (K.H.)

  20. Radiation therapy for age-related macular degeneration (ARMD)

    Mandai, Michiko; Ogura, Yuichiro [Kyoto Univ. (Japan). Faculty of Medicine

    1996-09-01

    Authors` results of low dose radiation therapy for ARMD were described. CT scan simulation was performed to determine the irradiation field of posterior pole of eyeball to which more than 90% of radiation was to be absorbed. The photon beam of 6MV was irradiated as to avoid lens at 2 Gy/day for 1 or 2 weeks to attain 10 or 20 Gy in total, respectively. After the treatment, the process was followed every 3 months and examinations with fluorescence contrasting, for visual field and for adverse radiation effects were done every 6 months. Results of reduction, no change and increase of choroidal neovascularization plate within 1 y were seen in 7 (47%), 4 (27%) and 4 eyes (27%) per total 15 eyes, respectively, in the treated group with 10 Gy whereas those in the control untreated group were 1 (6%), 6 (35%) and 10 (59%) eyes per 17 eyes, respectively (P<0.05). In addition, the treatment was effective for improvement of serous abruption and of retinal edema and for keeping optesthesia. The radiation therapy with 20 Gy was one too recently introduced to give enough results but may be more promising. (K.H.)

  1. Aesthetic results following partial mastectomy and radiation therapy

    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

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

    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. Dental extractions in relation to radiation therapy of 224 patients

    The case histories of 224 patients treated with radiation therapy for head and neck malignancies at the Radiotherapy Clinic of the Univesity Central Hospital in Turku during the years 1974-77 are reviewed. Of the 92 patients surviving for 5 years, 90 were available for re-examination. The median radiation dosage was 61 Gy in 6 to 8 weeks in patients with squamous cell carcinoma and othe solid tumours and 43 Gy in 5 weeks in patients with lymphoma. The oral status of the patients was examined clinically and radiographically. From these pationts 45 teeth had been extracted before irradiation and 94 after irradiation. In no case had this resulted in osteoradionecrosis of the jaws. It is evident that the repairing of patient's teeth before radiation treatment, coupled with continuous preventive care of caries, will prevent serious complications from arising. (author)

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

    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.

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

    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

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

    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)

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

    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.

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

    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

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

    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

  10. Criteria for radiation therapy following breast-conserving surgery based EIC, TW, ly, and n factor

    The usefulness of postoperative radiation therapy following breast-conserving surgery has been accepted, but reports have been published which identify cases in which postoperative radiation therapy is not necessary. We therefore compared the postoperative disease-free rate in 65 cases by classifying them into a radiation therapy group and a non-radiation therapy group based on the level of extensive intraductal component (EIC) and lymphatic invasion (ly) and the presence or absence of n factor. The results of this comparison showed that in cases with the absence or minimal presence of EIC and the absence of ly, postoperative radiation therapy should no significant effect. Of these cases, those with negative TW and negative or unknown lymph node metastasis showed satisfactory postoperative results, even without radiation therapy. Furthermore, salvage operation was possible, even following recurrence. It is therefore thought that postoperative radiation therapy is not necessarily indicated in these cases. (author)

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

    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)

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

    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.

  13. Radiation therapy for intracranial ependymomas: impact of age on outcome

    Purpose: The records of patients with intracranial ependymoma who received radiation therapy at UCSF were reviewed retrospectively to evaluate the impact of Karnofsky performance status (KPS), age, histology, and treatment on outcome. Materials and Methods: Between 1978 and 1996, 45 patients with intracranial ependymoma received postoperative radiation therapy. Overall survival (OS) and progression free survival (PFS) were calculated from the date of diagnosis. Median follow up for surviving patients was 72 months. Ages ranged from 4 months to 56 years, with a median of 8 years. The tumor was infratentorial in 35 and supratentorial in 10. All patients had either biopsy (3), subtotal resection (30), or gross total resection (12). There were 29 low grade and 16 anaplastic ependymomas. Thirty-seven patients received standard fractionation to a median dose of 54 Gy. Eight patients received hyperfractionation at 1.0 Gy BID to a median dose of 72 Gy. Thirty-eight patients had partial brain irradiation and seven had craniospinal irradiation. Twenty-three patients received adjuvant chemotherapy. For the infants ≤ 3 years old (n=12), all but one had a subtotal resection and most received chemotherapy prior to radiation therapy. Seven infants received radiation therapy at the time of disease progression and five had radiation therapy prior to progression. Most of the patients > 3 years old were irradiated prior to progression. Results: The five-year actuarial OS and PFS were 65% and 46% for the whole group. Histology and treatment factors such as extent of resection, hyperfractionation, and adjuvant chemotherapy did not significantly affect outcome. Overall, (25(45)) patients had disease progression. Only two patients failed in the brain outside the primary site. Six patients developed leptomeningeal spread (four concurrent with local failure and two subsequent to local failure). Five-year OS for patients ≤ 3 years old was 21% versus 80% for patients > 3 years old (p=0

  14. External radiation therapy in early stage prostate cancer

    Optimal therapy for adenocarcinoma of the prostate is controversial. Numerous options are available, however, comparison of results is difficult in view of the insufficiency of phase III randomized trials comparing alternative treatment strategies. These options include such strategies as no curative therapy (so-called watchful waiting), radiotherapy (external and/or internal), cryotherapy, or radical prostatectomy. Clearly, a broad spectrum of clinical approaches. When reported experiences involving radiation therapy and radical prostatectomy are compared, surgical patients tend to be younger, of earlier stage, of higher performance status, and have lower pre-therapy PSA. These prognostic factors influence the probability of disease control, and since patient selection can have a profound impact on results reporting, these issues need to be carefully controlled. A review of patients who are potentially candidates for surgery at the University of Michigan treated with conformal therapy external beam treatment, indicates that these relatively early patients are doing well. These issues will be elaborated upon further during the presentation

  15. On adaptation to the effect of ionizing radiation

    Determination of the notion adaptation and its application in biology and medicine where this notion is understood as accomodation which does not result from pathological consequences (physiological adaptation) is considered. Reactions to influence of those medium factors. Which have no receptors in the organims and those which are destructive at any structural level of the organism should not be called adaptation reactions. 18 refs

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

    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.

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

    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

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

    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.

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

    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

  20. 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

    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