Science.gov

Sample records for radiotherapy treatment process

  1. Dose errors in the treatment planning process of cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Myint, W. Kenji

    This thesis reports on the examination of specific dose errors in the treatment planning process. This process begins with the acquisition of the treatment planning CT (computed tomography) dataset and ends with the calculation of dose in the patient. The treatment planning CT is a Hounsfield unit (HU) representation of the patient that is converted to relative electron density in the treatment planning system. The treatment planning system utilizes a dose calculation algorithm to predict the dose based on the relative electron density distribution of the patient. The sources of dose error investigated in this thesis can be categorized as: (i) errors in the HU representation of the patient; (ii) errors in the relative electron density distribution of the patient; and (iii) errors in the dose calculation algorithm. Errors in the dose calculation algorithms were examined in Chapter 3, where the accuracy of the Theraplan Plus treatment planning system's implementation of the pencil beam and collapsed cone convolution algorithms were investigated in lung-equivalent material. Both algorithms had difficulty modeling the broadening of the beam in the lung-equivalent material but the collapsed cone convolution algorithm generally showed consistently smaller dose errors than the pencil beam algorithm. As expected, the pencil beam model could not model any lateral electron transport and the largest dose errors were observed near lateral lung-acrylic interfaces. In chapter 4, objects present during dose delivery but not accounted for in the treatment planning CT dataset were investigated. These can be categorized as errors in the HU representation of the patient. One such example is the treatment tabletop present during delivery, but replaced with a different table during the CT scan. In this study, the attenuation of the beam by a carbon fiber treatment tabletop was quantified and a practical solution to account for the tabletop was proposed. It was determined that

  2. The Impact of Colleague Peer Review on the Radiotherapy Treatment Planning Process in the Radical Treatment of Lung Cancer.

    PubMed

    Rooney, K P; McAleese, J; Crockett, C; Harney, J; Eakin, R L; Young, V A L; Dunn, M A; Johnston, R E; Hanna, G G

    2015-09-01

    Modern radiotherapy uses techniques to reliably identify tumour and reduce target volume margins. However, this can potentially lead to an increased risk of geographic miss. One source of error is the accuracy of target volume delineation (TVD). Colleague peer review (CPR) of all curative-intent lung cancer plans has been mandatory in our institution since May 2013. At least two clinical oncologists review plans, checking treatment paradigm, TVD, prescription dose tumour and critical organ tolerances. We report the impact of CPR in our institution. Radiotherapy treatment plans of all patients receiving radical radiotherapy were presented at weekly CPR meetings after their target volumes were reviewed and signed off by the treating consultant. All cases and any resultant change to TVD (including organs at risk) or treatment intent were recorded in our prospective CPR database. The impact of CPR over a 13 month period from May 2013 to June 2014 is reported. One hundred and twenty-two patients (63% non-small cell lung carcinoma, 17% small cell lung carcinoma and 20% 'clinical diagnosis') were analysed. On average, 3.2 cases were discussed per meeting (range 1-8). CPR resulted in a change in treatment paradigm in 3% (one patient proceeded to induction chemotherapy, two patients had high-dose palliative radiotherapy). Twenty-one (17%) had a change in TVD and one (1%) patient had a change in dose prescription. In total, 6% of patients had plan adjustment after review of dose volume histogram. The introduction of CPR in our centre has resulted in a change in a component of the treatment plan for 27% of patients receiving curative-intent lung radiotherapy. We recommend CPR as a mandatory quality assurance step in the planning process of all radical lung plans. Copyright © 2015 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  3. [Statistical Process Control (SPC) can help prevent treatment errors without increasing costs in radiotherapy].

    PubMed

    Govindarajan, R; Llueguera, E; Melero, A; Molero, J; Soler, N; Rueda, C; Paradinas, C

    2010-01-01

    Statistical Process Control (SPC) was applied to monitor patient set-up in radiotherapy and, when the measured set-up error values indicated a loss of process stability, its root cause was identified and eliminated to prevent set-up errors. Set up errors were measured for medial-lateral (ml), cranial-caudal (cc) and anterior-posterior (ap) dimensions and then the upper control limits were calculated. Once the control limits were known and the range variability was acceptable, treatment set-up errors were monitored using sub-groups of 3 patients, three times each shift. These values were plotted on a control chart in real time. Control limit values showed that the existing variation was acceptable. Set-up errors, measured and plotted on a X chart, helped monitor the set-up process stability and, if and when the stability was lost, treatment was interrupted, the particular cause responsible for the non-random pattern was identified and corrective action was taken before proceeding with the treatment. SPC protocol focuses on controlling the variability due to assignable cause instead of focusing on patient-to-patient variability which normally does not exist. Compared to weekly sampling of set-up error in each and every patient, which may only ensure that just those sampled sessions were set-up correctly, the SPC method enables set-up error prevention in all treatment sessions for all patients and, at the same time, reduces the control costs. Copyright © 2009 SECA. Published by Elsevier Espana. All rights reserved.

  4. Concentration modulated skin marker for radiotherapy treatment planning process.

    PubMed

    Özgüven, Yıldıray; Yücel, Birsen; Özyürek, Betül; Karakuş, Gülderen; Özgüven, Yücel

    2013-03-01

    For conformal radiotherapy, it is feasible to achieve high accuracy in contouring the outline of the target volume in treatment planning process. In contouring process, target volume is occasionally defined by means of either surgical clips or skin marker during patient anatomical data acquisition. Treatment planning systems are predicting invalid radiation dose distributions by using surgical clips and skin marker within the patient. Purpose of this study is the production of new skin marker which affects less dose distributions of electron beam. The influences of lead and commercial markers on dose calculations in a 3D treatment planning systems were investigated in terms of electron beam energy and dose profile depth. Dose deviation with commercial marker was observed to smaller than lead marker. However this dose deviation was still at big value. In order to reduce of this value, barium sulfate suspension and ultrasound gel were mixed with different volumetric ratio. With the purpose of acception the most suitable marker for radiation therapy, obtained new suspensions were investigated in terms of visibility and dose deviation. B:G/1:10 marker was determined to cause optimum visibility and the lowest dose deviation on dose calculations in terms of electron beam energy and dose profile depth. Appropriate marker, mixture of substances such as barium sulfate suspension and ultrasound gel can be produced. This marker is both ease of usage and practical and economical. Each clinic can prepare marker which is peculiar to suspension with different concentration of substance for specific visibility. But, it should be taken into account resultant dose deviation to beam calculation depending on barium sulfate concentration. Copyright © 2012 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  5. Caring for children undergoing radiotherapy treatment: Swedish radiotherapy nurses' perceptions.

    PubMed

    Gårdling, J; Edwinson Månsson, M; Törnqvist, E; Hallström, I

    2015-12-01

    The aim was to explore radiotherapy nurses' perceptions of their experiences of caring for children undergoing radiotherapy treatment for cancer. Semi-structured interviews of 12 nurses were conducted. The interviews were analysed using a phenomenographical approach. All interviewees were women, and the group's mean age was 49 years. Caring for children during radiotherapy treatment was perceived as a complex task. Their perceptions included views on providing holistic care, creating a sense of security and being committed. Through holistic care the radiotherapy nurses took responsibility regarding care for the child and family, technical aspects of the radiotherapy procedure and the development of their profession. They tried to create a sense of security through individualized information and preparation, through teamwork with the child and family, and regarding anaesthetic personnel (if needed) while balancing the care they gave related to the child, to the family, to anaesthetic personnel, and to their own tasks. The radiotherapy nurses perceived themselves as committed in their care and reported being emotionally affected by sadness, but also joy. By clarifying radiotherapy nurses perceptions of caring for children guidelines can be developed to lessen anxiety and increase the sense of security amongst children undergoing radiotherapy treatment and their family members. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Vega library for processing DICOM data required in Monte Carlo verification of radiotherapy treatment plans.

    PubMed

    Locke, C; Zavgorodni, S

    2008-12-01

    Monte Carlo (MC) methods provide the most accurate to-date dose calculations in heterogeneous media and complex geometries, and this spawns increasing interest in incorporating MC calculations into treatment planning quality assurance process. This involves MC dose calculations for clinically produced treatment plans. To perform these calculations, a number of treatment plan parameters specifying radiation beam and patient geometries need to be transferred to MC codes, such as BEAMnrc and DOSXYZnrc. Extracting these parameters from DICOM files is not a trivial task, one that has previously been performed mostly using Matlab-based software. This paper describes the DICOM tags that contain information required for MC modeling of conformal and IMRT plans, and reports the development of an in-house DICOM interface, through a library (named Vega) of platform-independent, object-oriented C++ codes. The Vega library is small and succinct, offering just the fundamental functions for reading/modifying/writing DICOM files in a C++ program. The library, however, is flexible enough to extract all MC required data from DICOM files, and write MC produced dose distributions into DICOM files that can then be processed in a treatment planning system environment. The library can be made available upon request to the authors.

  7. Radiotherapy in the treatment of vertebral hemangiomas

    SciTech Connect

    Faria, S.L.; Schlupp, W.R.; Chiminazzo, H. Jr.

    1985-02-01

    Symptomatic vertebral hemangiomas are not common. Although radiotherapy has been used as treatment, the data are sparse concerning total dose, fractionation and results. The authors report nine patients with vertebral hemangioma treated with 3000-4000 rad, 200 rad/day, 5 fractions per week, followed from 6 to 62 months. Seventy-seven percent had complete or almost complete disappearance of the symptoms. Radiotherapy schedules are discussed.

  8. Radiotherapy Treatment Planning for Testicular Seminoma

    SciTech Connect

    Wilder, Richard B.; Buyyounouski, Mark K.; Efstathiou, Jason A.; Beard, Clair J.

    2012-07-15

    Virtually all patients with Stage I testicular seminoma are cured regardless of postorchiectomy management. For patients treated with adjuvant radiotherapy, late toxicity is a major concern. However, toxicity may be limited by radiotherapy techniques that minimize radiation exposure of healthy normal tissues. This article is an evidence-based review that provides radiotherapy treatment planning recommendations for testicular seminoma. The minority of Stage I patients who choose adjuvant treatment over surveillance may be considered for (1) para-aortic irradiation to 20 Gy in 10 fractions, or (2) carboplatin chemotherapy consisting of area under the curve, AUC = 7 Multiplication-Sign 1-2 cycles. Two-dimensional radiotherapy based on bony anatomy is a simple and effective treatment for Stage IIA or IIB testicular seminoma. Centers with expertise in vascular and nodal anatomy may consider use of anteroposterior-posteroanterior fields based on three-dimensional conformal radiotherapy instead. For modified dog-leg fields delivering 20 Gy in 10 fractions, clinical studies support placement of the inferior border at the top of the acetabulum. Clinical and nodal mapping studies support placement of the superior border of all radiotherapy fields at the top of the T12 vertebral body. For Stage IIA and IIB patients, an anteroposterior-posteroanterior boost is then delivered to the adenopathy with a 2-cm margin to the block edge. The boost dose consists of 10 Gy in 5 fractions for Stage IIA and 16 Gy in 8 fractions for Stage IIB. Alternatively, bleomycin, etoposide, and cisplatin chemotherapy for 3 cycles or etoposide and cisplatin chemotherapy for 4 cycles may be delivered to Stage IIA or IIB patients (e.g., if they have a horseshoe kidney, inflammatory bowel disease, or a history of radiotherapy).

  9. Oral verrucous carcinoma. Treatment with radiotherapy

    SciTech Connect

    Nair, M.K.; Sankaranarayanan, R.; Padmanabhan, T.K.; Madhu, C.S.

    1988-02-01

    Fifty-two cases of oral verrucous carcinoma treated with radiotherapy at the Regional Cancer Centre, Trivandrum, Kerala, India in 1982 were evaluated to determine the distribution within the oral cavity, clinical extent, and effectiveness of radiotherapy in controlling the disease. The most common site was the buccal mucosa. Fifty percent of the patients had clinically negative regional lymph nodes and 33% were in earlier stages (T1, T2, N0, and M0). The overall 3-year no evidence of disease (NED) survival rate was 44%. The 3-year NED survival rate with radium implant was 86%. We cannot comment on anaplastic transformation after radiotherapy because our treatment failures have not been subjected for biopsy concerning this matter. Because the results are comparable with those of well-differentiated squamous cell carcinoma, we think that the treatment policies advocated for oral squamous cell carcinoma are also applicable to oral verrucous carcinoma.

  10. Medical treatment for biochemical relapse after radiotherapy.

    PubMed

    Quero, L; Hennequin, C

    2014-10-01

    This article's purpose was to review the medical data justifying the use of a medical treatment for biochemical relapse after external beam radiotherapy. The MEDLINE database was searched to identify relevant information with the following medical subject headings: "prostate cancer", "radiotherapy" and "biochemical relapse". Prognostic factors affecting the overall survival of patients with a biochemical relapse after external beam radiotherapy have been identified: short prostate specific antigen (PSA)-doubling time (< 12 months), high PSA value (> 10 ng/mL) and short interval between treatment and biochemical relapse (< 18 months). If a second local treatment is not feasible, timing to initiate a salvage medical treatment is not defined. Particularly, randomized trials did not demonstrate a significant benefit of an early initiation of androgen deprivation treatment. Some retrospective studies suggest that an early androgen deprivation is justified if poor prognostic factors are found. However, if an androgen deprivation treatment is prescribed, intermittent schedule is non-inferior to a continuous administration and seems to offer a better quality of life. Many non-hormonal treatments have also been evaluated in this setting: only 5-alpha-reductase inhibitors could be proposed in some specific situations. In conclusion, the judicious use of a medical treatment for biochemical relapse is still debated. Given the natural history of this clinical situation, a simple surveillance is justified in many cases.

  11. Integer programming for improving radiotherapy treatment efficiency.

    PubMed

    Lv, Ming; Li, Yi; Kou, Bo; Zhou, Zhili

    2017-01-01

    Patients received by radiotherapy departments are diverse and may be diagnosed with different cancers. Therefore, they need different radiotherapy treatment plans and thus have different needs for medical resources. This research aims to explore the best method of scheduling the admission of patients receiving radiotherapy so as to reduce patient loss and maximize the usage efficiency of service resources. A mix integer programming (MIP) model integrated with special features of radiotherapy is constructed. The data used here is based on the historical data collected and we propose an exact method to solve the MIP model. Compared with the traditional First Come First Served (FCFS) method, the new method has boosted patient admission as well as the usage of linear accelerators (LINAC) and beds. The integer programming model can be used to describe the complex problem of scheduling radio-receiving patients, to identify the bottleneck resources that hinder patient admission, and to obtain the optimal LINAC-bed radio under the current data conditions. Different management strategies can be implemented by adjusting the settings of the MIP model. The computational results can serve as a reference for the policy-makers in decision making.

  12. Radiotherapy in the treatment of postoperative chylothorax

    PubMed Central

    2013-01-01

    Background Chylothorax is characterized by the presence of chyle in the pleural cavity. The healing rate of non-operative treatment varies enormously; the maximum success rate in series is 70%. We investigate the efficacy and outcomes of radiotherapy for postoperative chylothorax. Methods Chylothorax was identified based on the quantity and quality of the drainage fluid. Radiation was indicated if the daily chyle flow exceeded 450 ml after complete cessation of oral intake. Radiotherapy consisted of opposed isocentric portals to the mediastinum using 15 MV photon beams from a linear accelerator, a single dose of 1–1.5 Gy, and a maximum of five fractions per week. The radiation target area was the anatomical region between TH3 and TH10 depending on the localization of the resected lobe. The mean doses of the ionizing energy was 8.5 Gy ± 3.5 Gy. Results The median start date of the radiation was the fourth day after chylothorax diagnosis. The patients’ mediastinum was radiated an average of six times. Radiotherapy, in combination with dietary restrictions, was successful in all patients. The median time between the end of the radiation and the removal of the chest tube was one day. One patient underwent wound healing by secondary intention. The median time between the end of radiation and discharge was three days, and the overall hospital stay between the chylothorax diagnosis and discharge was 18 days (range: 11–30 days). After a follow-up of six months, no patient experienced chylothorax recurrence. Conclusions Our results suggest that radiotherapy in combination with dietary restriction in the treatment of postoperative chylothorax is very safe, rapid and successful. This novel interventional procedure can obviate repeat major thoracic surgery and shorten hospital stays and could be the first choice in the treatment of postthoracotomy chylothorax. PMID:23566741

  13. More Ions for Radiotherapy: About Treatment Planning and Track Simulations

    NASA Astrophysics Data System (ADS)

    Krämer, M.

    2017-03-01

    In the recent years, irradiation with swift light ions - from protons up to oxygen -has become an established method in tumour radiotherapy.A prerequisite for successful treatment is the sufficient knowledge of physical and radiobiological processes down to the microscopic or even nanoscopic scale. This report summarizes recent developments. In particular the application of ions other than protons and carbon will be addressed, as well as modelling approaches on the nanoscale.

  14. Statistical process control for radiotherapy quality assurance.

    PubMed

    Pawlicki, Todd; Whitaker, Matthew; Boyer, Arthur L

    2005-09-01

    Every quality assurance process uncovers random and systematic errors. These errors typically consist of many small random errors and a very few number of large errors that dominate the result. Quality assurance practices in radiotherapy do not adequately differentiate between these two sources of error. The ability to separate these types of errors would allow the dominant source(s) of error to be efficiently detected and addressed. In this work, statistical process control is applied to quality assurance in radiotherapy for the purpose of setting action thresholds that differentiate between random and systematic errors. The theoretical development and implementation of process behavior charts are described. We report on a pilot project is which these techniques are applied to daily output and flatness/symmetry quality assurance for a 10 MV photon beam in our department. This clinical case was followed over 52 days. As part of our investigation, we found that action thresholds set using process behavior charts were able to identify systematic changes in our daily quality assurance process. This is in contrast to action thresholds set using the standard deviation, which did not identify the same systematic changes in the process. The process behavior thresholds calculated from a subset of the data detected a 2% change in the process whereas with a standard deviation calculation, no change was detected. Medical physicists must make decisions on quality assurance data as it is acquired. Process behavior charts help decide when to take action and when to acquire more data before making a change in the process.

  15. Dosimetry audit of radiotherapy treatment planning systems.

    PubMed

    Bulski, Wojciech; Chełmiński, Krzysztof; Rostkowska, Joanna

    2015-07-01

    In radiotherapy Treatment Planning Systems (TPS) various calculation algorithms are used. The accuracy of dose calculations has to be verified. Numerous phantom types, detectors and measurement methodologies are proposed to verify the TPS calculations with dosimetric measurements. A heterogeneous slab phantom has been designed within a Coordinated Research Project (CRP) of the IAEA. The heterogeneous phantom was developed in the frame of the IAEA CRP. The phantom consists of frame slabs made with polystyrene and exchangeable inhomogeneity slabs equivalent to bone or lung tissue. Special inserts allow to position thermoluminescent dosimeters (TLD) capsules within the polystyrene slabs below the bone or lung equivalent slabs and also within the lung equivalent material. Additionally, there are inserts that allow to position films or ionisation chamber in the phantom. Ten Polish radiotherapy centres (of 30 in total) were audited during on-site visits. Six different TPSs and five calculation algorithms were examined in the presence of inhomogeneities. Generally, most of the results from TLD were within 5 % tolerance. Differences between doses calculated by TPSs and measured with TLD did not exceed 4 % for bone and polystyrene equivalent materials. Under the lung equivalent material, on the beam axis the differences were lower than 5 %, whereas inside the lung equivalent material, off the beam axis, in some cases they were of around 7 %. The TLD results were confirmed with the ionisation chamber measurements. The comparison results of the calculations and the measurements allow to detect limitations of TPS calculation algorithms. The audits performed with the use of heterogeneous phantom and TLD seem to be an effective tool for detecting the limitations in the TPS performance or beam configuration errors at audited radiotherapy departments.

  16. Ion beams in radiotherapy - from tracks to treatment planning

    NASA Astrophysics Data System (ADS)

    Krämer, M.; Scifoni, E.; Wälzlein, C.; Durante, M.

    2012-07-01

    Several dozen clinical sites around the world apply beams of fast light ions for radiotherapeutical purposes. Thus there is a vested interest in the various physical and radiobiological processes governing the interaction of ion beams with matter, specifically living systems. We discuss the various modelling steps which lead from basic interactions to the application in actual patient treatment planning. The nano- and microscopic scale is covered by sample calculations with our TRAX code. On the macroscopic scale we feature the TRiP98 treatment planning system, which was clinically used in GSI's radiotherapy pilot project.

  17. Radiotherapy treatments using Tsallis entropy statistical approach

    NASA Astrophysics Data System (ADS)

    D, Rodríguez-Pérez; O, Sotolongo-Grau; O, Sotolongo-Costa; C, Antoranz J.

    2014-03-01

    Several radiobiological models mimic the biologic effect of one single radiation dose on a living tissue. However, the actual fractionated radiotherapy requires accounting for a new magnitude, i.e., time. Here, we explore the biological consequences posed by the mathematical prolongation of a previous single radiation model to fractionated treatment. The survival fraction is obtained, together with the equivalent physical dose, in terms of a time dependent factor (similar to a repair coefficient) describing the tissue trend to recovering its radioresistance. The model describes how dose fractions add up to obtain the equivalent dose and how the repair coefficient poses a limit to reach an equivalent dose equal to the critical one that would completely annihilate the tumor. On the other hand, the surrounding healthy tissue is a limiting factor to treatment planning. This tissue has its own repair coefficient and thus should limit the equivalent dose of a treatment. Depending on the repair coefficient and the critical dose of each tissue, unexpected results (failure to fully remove the tumor) can be obtained. To illustrate these results and predictions, some realistic example calculations will be performed using parameter values within actual clinical ranges. In conclusion, the model warns about treatment limitations and proposes ways to overcome them.

  18. System Toward Automation in Radiotherapy Treatment: START

    NASA Astrophysics Data System (ADS)

    Cheng, Andrew Y. S.; Tsoi, Kenneth Y. P.

    1994-10-01

    START is a new automation system invented for nasopharyngeal carcinoma treatment. A laser scanner system capable of non-contact digitization of 3D surface is used to digitize the contours of the patient's face, shoulder and special landmark reference features of the patient. These features are stored in the computer in 3D digitized format. The digitized facial features with traced landmark reference features are used for fabrication of a true sized wood-particle laminates mould by a computer numerical controlled milling system. A Cobex mask is formed on this mould by using vacuum forming technique. With an image analysis and computer aided design system, the X-ray film with treatment window marked is traced automatically and converted to match the prescanned 3D information. A computer controlled 6-axis robot can precisely mark out the required areas on the Cobex cast for treatment. Finally, the patient receives radiotherapy treatment with the Cobex case as a positioning registration device. The new system will replace the manual procedure with better patient comfort, higher efficiency and enhanced accuracy.

  19. Collision prediction software for radiotherapy treatments.

    PubMed

    Padilla, Laura; Pearson, Erik A; Pelizzari, Charles A

    2015-11-01

    This work presents a method of collision predictions for external beam radiotherapy using surface imaging. The present methodology focuses on collision prediction during treatment simulation to evaluate the clearance of a patient's treatment position and allow for its modification if necessary. A Kinect camera (Microsoft, Redmond, WA) is used to scan the patient and immobilization devices in the treatment position at the simulator. The surface is reconstructed using the skanect software (Occipital, Inc., San Francisco, CA). The treatment isocenter is marked using simulated orthogonal lasers projected on the surface scan. The point cloud of this surface is then shifted to isocenter and converted from Cartesian to cylindrical coordinates. A slab models the treatment couch. A cylinder with a radius equal to the normal distance from isocenter to the collimator plate, and a height defined by the collimator diameter is used to estimate collisions. Points within the cylinder clear through a full gantry rotation with the treatment couch at 0°, while points outside of it collide. The angles of collision are reported. This methodology was experimentally verified using a mannequin positioned in an alpha cradle with both arms up. A planning CT scan of the mannequin was performed, two isocenters were marked in pinnacle, and this information was exported to AlignRT (VisionRT, London, UK)--a surface imaging system for patient positioning. This was used to ensure accurate positioning of the mannequin in the treatment room, when available. Collision calculations were performed for the two treatment isocenters and the results compared to the collisions detected the room. The accuracy of the Kinect-Skanect surface was evaluated by comparing it to the external surface of the planning CT scan. Experimental verification results showed that the predicted angles of collision matched those recorded in the room within 0.5°, in most cases (largest deviation -1.2°). The accuracy study for

  20. Collision prediction software for radiotherapy treatments

    SciTech Connect

    Padilla, Laura; Pearson, Erik A.; Pelizzari, Charles A.

    2015-11-15

    Purpose: This work presents a method of collision predictions for external beam radiotherapy using surface imaging. The present methodology focuses on collision prediction during treatment simulation to evaluate the clearance of a patient’s treatment position and allow for its modification if necessary. Methods: A Kinect camera (Microsoft, Redmond, WA) is used to scan the patient and immobilization devices in the treatment position at the simulator. The surface is reconstructed using the SKANECT software (Occipital, Inc., San Francisco, CA). The treatment isocenter is marked using simulated orthogonal lasers projected on the surface scan. The point cloud of this surface is then shifted to isocenter and converted from Cartesian to cylindrical coordinates. A slab models the treatment couch. A cylinder with a radius equal to the normal distance from isocenter to the collimator plate, and a height defined by the collimator diameter is used to estimate collisions. Points within the cylinder clear through a full gantry rotation with the treatment couch at 0° , while points outside of it collide. The angles of collision are reported. This methodology was experimentally verified using a mannequin positioned in an alpha cradle with both arms up. A planning CT scan of the mannequin was performed, two isocenters were marked in PINNACLE, and this information was exported to AlignRT (VisionRT, London, UK)—a surface imaging system for patient positioning. This was used to ensure accurate positioning of the mannequin in the treatment room, when available. Collision calculations were performed for the two treatment isocenters and the results compared to the collisions detected the room. The accuracy of the Kinect-Skanect surface was evaluated by comparing it to the external surface of the planning CT scan. Results: Experimental verification results showed that the predicted angles of collision matched those recorded in the room within 0.5°, in most cases (largest deviation

  1. Improving radiotherapy in cancer treatment: Promises and challenges

    PubMed Central

    Chen, Helen H.W.; Kuo, Macus Tien

    2017-01-01

    Effective radiotherapy for cancer has relied on the promise of maximally eradicating tumor cells while minimally killing normal cells. Technological advancement has provided state-of-the-art instrumentation that enables delivery of radiotherapy with great precision to tumor lesions with substantial reduced injury to normal tissues. Moreover, better understanding of radiobiology, particularly the mechanisms of radiation sensitivity and resistance in tumor lesions and toxicity in normal tissues, has improved the treatment efficacy of radiotherapy. Previous mechanism-based studies have identified many cellular targets that can affect radiation sensitivity, notably reactive oxygen species, DNA-damaging response signals, and tumor microenvironments. Several radiation sensitizers and protectors have been developed and clinically evaluated; however, many of these results are inconclusive, indicating that improvement remains needed. In this era of personalized medicine in which patients’ genetic variations, transcriptome and proteomics, tumor metabolism and microenvironment, and tumor immunity are available. These new developments have provided opportunity for new target discovery. Several radiotherapy sensitivity-associated “gene signatures” have been reported although clinical validations are needed. Recently, several immune modifiers have been shown to associate with improved radiotherapy in preclinical models and in early clinical trials. Combination of radiotherapy and immunocheckpoint blockade has shown promising results especially in targeting metastatic tumors through abscopal response. In this article, we succinctly review recent advancements in the areas of mechanism-driven targets and exploitation of new targets from current radio-oncogenomic and radiation-immunotherapeutic approaches that bear clinical implications for improving the treatment efficacy of radiotherapy.

  2. Synergistic Effects of Gold Nanocages in Hyperthermia and Radiotherapy Treatment

    NASA Astrophysics Data System (ADS)

    Zhang, Ai-wei; Guo, Wei-hua; Qi, Ya-fei; Wang, Jian-zhen; Ma, Xiang-xing; Yu, De-xin

    2016-06-01

    Gold nanocages (GNCs) are a promising material that not only converts near infrared (NIR) light to heat for the ablation of tumors but also acts as a radiosensitizer. The combination of hyperthermia and radiotherapy has a synergistic effect that can lead to significant tumor cell necrosis. In the current study, we synthesized GNCs that offered the combined effects of hyperthermia and radiotherapy. This combination strategy resulted in increased tumor cell apoptosis and significant tumor tissue necrosis. We propose that GNCs can be used for clinical treatment and to potentially overcome resistance to radiotherapy by clearly increasing the antitumor effect.

  3. Treatment of ameloblastoma and ameloblastic carcinoma with radiotherapy.

    PubMed

    Kennedy, William R; Werning, John W; Kaye, Frederic J; Mendenhall, William M

    2016-10-01

    The purpose of this study is to report our institutional experience using radiotherapy in the treatment of ameloblastoma and ameloblastic carcinoma. Three patients with ameloblastoma and 3 patients with ameloblastic carcinoma were treated with radiotherapy alone (2 patients) or surgery and postoperative radiotherapy (4 patients) at the University of Florida between 1973 and 2007. Follow-up ranged from 4.0 to 13.1 years with a median of 7.8 years. Radiotherapy complications were scored using the Common Terminology Criteria for Adverse Events, version 4.0. Local control was achieved in 4 of the 6 patients. One patient treated with RT alone for an unresectable ameloblastoma developed a local recurrence and metastases in both the cervical lymph nodes and lungs, but had excellent response to dual BRAF/MEK inhibition with dabrafenib and trametinib. Another patient treated with surgery and postoperative radiotherapy for an ameloblastic carcinoma recurred locally without metastasis, but was not salvaged. No significant treatment-related complications were observed. For patients with local recurrence or inadequate margins after surgery, adjuvant radiotherapy provides the potential for disease control. In the setting of metastatic disease, targeted therapies may provide an additional opportunity for salvage.

  4. [FMEA applied to the radiotherapy patient care process].

    PubMed

    Meyrieux, C; Garcia, R; Pourel, N; Mège, A; Bodez, V

    2012-10-01

    Failure modes and effects analysis (FMEA), is a risk analysis method used at the Radiotherapy Department of Institute Sainte-Catherine as part of a strategy seeking to continuously improve the quality and security of treatments. The method comprises several steps: definition of main processes; for each of them, description for every step of prescription, treatment preparation, treatment application; identification of the possible risks, their consequences, their origins; research of existing safety elements which may avoid these risks; grading of risks to assign a criticality score resulting in a numerical organisation of the risks. Finally, the impact of proposed corrective actions was then estimated by a new grading round. For each process studied, a detailed map of the risks was obtained, facilitating the identification of priority actions to be undertaken. For example, we obtain five steps in patient treatment planning with an unacceptable level of risk, 62 a level of moderate risk and 31 an acceptable level of risk. The FMEA method, used in the industrial domain and applied here to health care, is an effective tool for the management of risks in patient care. However, the time and training requirements necessary to implement this method should not be underestimated. Copyright © 2012 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  5. [Radiotherapy as primary treatment for chemodectoma?].

    PubMed

    Verniers, D; Van Limbergen, E; Leysen, J; Ostyn, F; Segers, A

    1990-01-01

    Chemodectomas are slowly growing tumours originating in the chemoreceptor bodies. The diagnosis is based on typical clinical symptoms and radiological investigation. CT scanning with contrast enhancement permits to establish diagnosis in most cases and gives a correct idea of tumour size, tumour extension, displacement of arteries and bone destruction. Small tympanic chemodectomas are successfully managed by surgery, without causing additional cranial nerve palsies. Surgery of larger lesions is frequently followed by a high percentage of local recurrence (greater than 50%) and important morbidity (neurologic sequelae). Our present series confirms that these tumours can successfully be treated by radiotherapy. Persisting local control rates can be obtained in more than 90% of cases with moderate doses (45-50 Gy in 5 weeks) of carefully planned radiotherapy.

  6. The role of radiotherapy in multimodal treatment of pancreatic carcinoma

    PubMed Central

    2010-01-01

    Pancreatic ductal carcinoma is one of the most lethal malignancies, but in recent years a number of positive developments have occurred in the management of pancreatic carcinoma. This article aims to give an overview of the current knowledge regarding the role of radiotherapy in the treatment of pancreatic ductal adenocarcinoma (PDAC). The results of meta-analyses, phase III-studies, and phase II-studies using chemoradiotherapy and chemotherapy for resectable and non-resectable PDAC were reviewed. The use of radiotherapy is discussed in the neoadjuvant and adjuvant settings as well as in the locally advanced situation. Whenever possible, radiotherapy should be performed as simultaneous chemoradiotherapy. Patients with PDAC should be offered entry into clinical trials to identify optimal treatment results. PMID:20615227

  7. PET/CT for radiotherapy: image acquisition and data processing.

    PubMed

    Bettinardi, V; Picchio, M; Di Muzio, N; Gianolli, L; Messa, C; Gilardi, M C

    2010-10-01

    This paper focuses on acquisition and processing methods in positron emission tomography/computed tomography (PET/CT) for radiotherapy (RT) applications. The recent technological evolutions of PET/CT systems are described. Particular emphasis is dedicated to the tools needed for the patient positioning and immobilization, to be used in PET/CT studies as well as during RT treatment sessions. The effect of organ and lesion motion due to patient's respiration on PET/CT imaging is discussed. Breathing protocols proposed to minimize PET/CT spatial mismatches in relation to respiratory movements are illustrated. The respiratory gated (RG) 4D-PET/CT techniques, developed to measure and compensate for organ and lesion motion, are then introduced. Finally a description is provided of different acquisition and data processing techniques, implemented with the aim at improving: i) image quality and quantitative accuracy of PET images, and ii) target volume definition and treatment planning in RT, by using specific and personalised motion information.

  8. Digital Imaging Techniques for Radiotherapy Treatment Verification

    NASA Astrophysics Data System (ADS)

    Leszczynski, Konrad Wojciech

    The curative effect of ionizing radiation depends strongly upon the precision with which dose is delivered to the prescribed target volume. The requirement for high geometric accuracy in patient positioning is even more stringent where complex treatment techniques are used, such as conformal, dynamic arc or truly 3-D (non-coplanar) beams. It is expected that digital on-line portal imaging devices will play a key role in the monitoring of radiation therapy treatments. Different approaches to on-line portal image acquisition have been compared, and the basic imaging properties of a video portal imager have been evaluated and discussed in this thesis. Analysis of the system performance indicates the most efficient ways to effect improvements in spatial resolution and signal-to-noise ratio. Digital image processing techniques for noise suppression and contrast enhancement have been developed and implemented in order to facilitate visual analysis of on-line portal images. Results obtained with phantom and clinical images indicate that improvement in image quality can be achieved using adaptive filtering and local histogram modification. A novel study of observer performance with on-line portal images showed that enhancement of contrast by selective local histogram modification significantly improves perceptibility of anatomical landmarks and assures higher accuracy in quantitative computer-assisted treatment verification. Fully automated treatment verification is the ultimate goal of on-line digital portal imaging. It should include analysis of size and shape of the radiation field as well as evaluation of placement of the field with respect to the internal anatomy of the patient. A computerized technique, has been developed, for extraction of the treatment field edges and for parametrization of the field, and examples of its application to automated analysis of size and shape of the radiation field are presented.

  9. Associations between nutritional status, weight loss, radiotherapy treatment toxicity and treatment outcomes in gastrointestinal cancer patients.

    PubMed

    Hill, Amanda; Kiss, Nicole; Hodgson, Belinda; Crowe, Timothy C; Walsh, Adam D

    2011-02-01

    Patients with gastrointestinal cancers are susceptible to nutritional deterioration which may be compounded by radiotherapy treatment toxicities. This study aimed to determine whether nutritional status at radiotherapy commencement or changes in nutritional status throughout radiotherapy were associated with treatment toxicity and outcomes in gastrointestinal cancer patients. Seventy-three gastrointestinal cancer patients receiving curative radiotherapy underwent medical record audits assessing body weight, radiotherapy toxicity, unplanned treatment breaks or hospital admissions and completion of prescribed treatment/s. Nutritional status was assessed in a subset of patients (n = 11) using the Patient-Generated Subjective Global Assessment tool. Seventy-five percent of patients lost weight throughout radiotherapy. Weight loss was significantly greater in patients experiencing unplanned radiotherapy breaks (-3.1% vs -1.6%, p < 0.05) and in patients not completing prescribed chemotherapy (-3.3% vs -1.6%, p < 0.05). Toxicity severity was strongly correlated with Patient-Generated Subjective Global Assessment score (rho = 0.839, p < 0.001) and was increased in patients experiencing unplanned admissions compared to those without admission (42.1% vs 9.3% with grade 3 toxicity respectively, p < 0.001). Deterioration in nutritional status during radiotherapy (as measured by weight loss) may be associated with poorer short-term treatment outcomes in gastrointestinal cancer patients. Patient numbers were too small to definitively determine the effect of nutritional status at radiotherapy commencement or changes in nutritional status throughout radiotherapy (defined by PG-SGA) on treatment outcomes. Further research is required to investigate this in larger, longer-term studies. Copyright © 2010. Published by Elsevier Ltd.

  10. Automatic liver contouring for radiotherapy treatment planning.

    PubMed

    Li, Dengwang; Liu, Li; Kapp, Daniel S; Xing, Lei

    2015-10-07

    To develop automatic and efficient liver contouring software for planning 3D-CT and four-dimensional computed tomography (4D-CT) for application in clinical radiation therapy treatment planning systems.The algorithm comprises three steps for overcoming the challenge of similar intensities between the liver region and its surrounding tissues. First, the total variation model with the L1 norm (TV-L1), which has the characteristic of multi-scale decomposition and an edge-preserving property, is used for removing the surrounding muscles and tissues. Second, an improved level set model that contains both global and local energy functions is utilized to extract liver contour information sequentially. In the global energy function, the local correlation coefficient (LCC) is constructed based on the gray level co-occurrence matrix both of the initial liver region and the background region. The LCC can calculate the correlation of a pixel with the foreground and background regions, respectively. The LCC is combined with intensity distribution models to classify pixels during the evolutionary process of the level set based method. The obtained liver contour is used as the candidate liver region for the following step. In the third step, voxel-based texture characterization is employed for refining the liver region and obtaining the final liver contours.The proposed method was validated based on the planning CT images of a group of 25 patients undergoing radiation therapy treatment planning. These included ten lung cancer patients with normal appearing livers and ten patients with hepatocellular carcinoma or liver metastases. The method was also tested on abdominal 4D-CT images of a group of five patients with hepatocellular carcinoma or liver metastases. The false positive volume percentage, the false negative volume percentage, and the dice similarity coefficient between liver contours obtained by a developed algorithm and a current standard delineated by the expert group

  11. Automatic liver contouring for radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Li, Dengwang; Liu, Li; Kapp, Daniel S.; Xing, Lei

    2015-09-01

    To develop automatic and efficient liver contouring software for planning 3D-CT and four-dimensional computed tomography (4D-CT) for application in clinical radiation therapy treatment planning systems. The algorithm comprises three steps for overcoming the challenge of similar intensities between the liver region and its surrounding tissues. First, the total variation model with the L1 norm (TV-L1), which has the characteristic of multi-scale decomposition and an edge-preserving property, is used for removing the surrounding muscles and tissues. Second, an improved level set model that contains both global and local energy functions is utilized to extract liver contour information sequentially. In the global energy function, the local correlation coefficient (LCC) is constructed based on the gray level co-occurrence matrix both of the initial liver region and the background region. The LCC can calculate the correlation of a pixel with the foreground and background regions, respectively. The LCC is combined with intensity distribution models to classify pixels during the evolutionary process of the level set based method. The obtained liver contour is used as the candidate liver region for the following step. In the third step, voxel-based texture characterization is employed for refining the liver region and obtaining the final liver contours. The proposed method was validated based on the planning CT images of a group of 25 patients undergoing radiation therapy treatment planning. These included ten lung cancer patients with normal appearing livers and ten patients with hepatocellular carcinoma or liver metastases. The method was also tested on abdominal 4D-CT images of a group of five patients with hepatocellular carcinoma or liver metastases. The false positive volume percentage, the false negative volume percentage, and the dice similarity coefficient between liver contours obtained by a developed algorithm and a current standard delineated by the expert group

  12. MR Imaging Based Treatment Planning for Radiotherapy of Prostate Cancer

    DTIC Science & Technology

    2007-02-01

    image- guided stereotactic localization in the hypofractionated treatment of lung cancer. Int. J. Rad. Oncol. Bio. Phys. 66: 738-747, 2006. Chapters...L, Ma C. Benefit of 3D image-guided stereotactic localization in the hypofractionated treatment of lung cancer. Proc. Medical Physics, 33(6), 1993...9. Amer AM, Mott J, Mackay RI, et al. Prediction of the benefits from dose-escalated hypofractionated intensity-modulated radiotherapy for

  13. Stereotactic fractionated radiotherapy for the treatment of benign meningiomas

    SciTech Connect

    Candish, Charles; McKenzie, Michael . E-mail: mmckenzi@bccancer.bc.edu; Clark, Brenda G.; Ma, Roy; Lee, Richard; Vollans, Emily; Robar, James; Gete, Ermias; Martin, Monty

    2006-11-15

    Purpose: To assess the use of stereotactic fractionated radiotherapy (SRT) for the treatment of meningiomas. Methods and Materials: Between April 1999 and October 2004, 38 patients underwent SRT. Of 34 patients (36 tumors) assessed, the median age was 53 years. The indication was primary treatment in 26 cases (no histology) and postoperative in 10 cases. The most common sites were cavernous sinus (17), optic nerve (6), and cerebellopontine angle (5). The median gross target volume and planning target volume were 8.9 cm{sup 3} and 18.9 cm{sup 3}, respectively. Stereotactic treatment was delivered with 6-MV photons with static conformal fields (custom-made blocks, 9 patients, and micromultileaf collimator, 25 patients). Median number of fields was six. The median dose prescribed was 50 Gy (range, 45-50.4 Gy) in 28 fractions. The median homogeneity and conformality indices were 1.1 and 1.79, respectively. Results: Treatment was well tolerated. Median follow-up was 26 months with 100% progression-free survival. One patient developed an area of possible radionecrosis related to previous radiotherapy, and 2 men developed mild hypogonadism necessitating testosterone replacement. The vision of 5 of 6 patients with optic pathway meningiomas improved or remained static. Conclusions: Stereotactic fractionated radiotherapy for the treatment of meningiomas is practical, and with early follow-up, seems to be effective.

  14. MR Imaging Based Treatment Planning for Radiotherapy of Prostate Cancer

    DTIC Science & Technology

    2005-02-01

    Ma C, Paskalev K, Jacob R, Chen L, Feigenberg S, Movsas B. Feasibility study for clinical implementation of dose hypofractionation with IMRT for...from or supported in part by this grant: NIH R01 (PI: Wang L): Improving treatment accuracy for hypofractionated SRT (submitted in Oct. 2004...E E K et al 2003 Evidence for efficacy without increased toxicity of hypofractionated radiotherapy for prostate carcinoma: early results of a Phase

  15. Partial differential equations-based segmentation for radiotherapy treatment planning.

    PubMed

    Gibou, Frederic; Levy, Doron; Cardenas, Carlos; Liu, Pingyu; Boyer, Arthur

    2005-04-01

    The purpose of this study is to develop automatic algorithms for the segmentation phase of radiotherapy treatment planning. We develop new image processing techniques that are based on solving a partial diferential equation for the evolution of the curve that identifies the segmented organ. The velocity function is based on the piecewise Mumford-Shah functional. Our method incorporates information about the target organ into classical segmentation algorithms. This information, which is given in terms of a three- dimensional wireframe representation of the organ, serves as an initial guess for the segmentation algorithm. We check the performance of the new algorithm on eight data sets of three diferent organs: rectum, bladder, and kidney. The results of the automatic segmentation were compared with a manual seg- mentation of each data set by radiation oncology faculty and residents. The quality of the automatic segmentation was measured with the k-statistics", and with a count of over- and undersegmented frames, and was shown in most cases to be very close to the manual segmentation of the same data. A typical segmentation of an organ with sixty slices takes less than ten seconds on a Pentium IV laptop.

  16. The synergistic effects of traditional Chinese herbs and radiotherapy for cancer treatment

    PubMed Central

    JIA, LILI; MA, SHUMEI; HOU, XUE; WANG, XIN; QASED, ABU BAKER LAYTH; SUN, XUEFEI; LIANG, NAN; LI, HUICHENG; YI, HEQING; KONG, DEJUAN; LIU, XIAODONG; FAN, FEIYUE

    2013-01-01

    Traditional Chinese medicine (TCM) has been demonstrated to have potent cytotoxic activity against certain malignant tumors. Ionizing radiation (IR) is one of the most effective methods used in the clinical treatment of cancer. The drawback of a single formula is that it limits the treatment efficacy for cancer, while comprehensive strategies require additional theoretical support. However, a combination of different antitumor treatment modalities is advantageous in restricting the non-specific toxicity often observed with an extremely high dose of a single regimen. The induction of apoptotic cell death is a significant process in tumor cells following radiotherapy or chemotherapy, and resistance to these treatments has been linked to a low propensity for apoptosis. Autophagy is a response of cancer cells to IR or chemotherapy, and involves the prominent formation of autophagic vacuoles in the cytoplasm. In this review, the synergistic effects of TCM and radiotherapy are summarized and the underlying mechanisms are illustrated, providing new therapeutic strategies for cancer. PMID:23760551

  17. Radiotherapy combined with surgery as treatment for advanced cervical cancer.

    PubMed

    Perches, R D; Lobaton, A T; Garcia, M C

    1983-12-01

    Experience obtained in a group of 44 patients with advanced cervical cancer is reported here. In this study, patients with residual cancer underwent laparotomy eight weeks after one or two different radiotherapy protocols. Sixty-eight percent of patients underwent radical surgery, 85% of patients pelvic exenterations, and 15% radical hysterectomies. In 27% of patients, no evidence of residual cancer was found in surgical specimens. Radical surgery was well tolerated, and one-third of patients were free of disease for one year or more. Control of disease was obtained in 50% of pelvic exenterations and in 60% of radical hysterectomies, regardless of prognosis, clinical stage or radiotherapy scheme. Although results show an improvement of up to 22% when comparing this to other more conventional treatments, we have concluded that we must obtain a wider experience in order to support our findings.

  18. Colonic explosion during treatment of radiotherapy complications in prostatic cancer

    PubMed Central

    TRASTULLI, STEFANO; BARILLARO, IVAN; DESIDERIO, JACOPO; DI ROCCO, GIORGIO; COCHETTI, GIOVANNI; MECARELLI, VALERIO; CIROCCHI, ROBERTO; SANTORO, ALBERTO; BOSELLI, CARLO; REDLER, ADRIANO; AVENIA, NICOLA; NOYA, GIUSEPPE

    2012-01-01

    The use of lasers has been of great importance in the field of endoscopy and surgery for their applications in coagulation and the ability to vaporize tissue. In the 1990s, new machines were introduced based on a different technology, the argon-plasma-coagulation (APC) system. This technology causes different biological effects without direct contact. An example is the hemostasis of bleeding. In the literature, several cases of complications have been reported during endoscopic treatment with APC. In this study, we report our experience of a case with colon explosion during an APC procedure for bleeding due to radiotherapy and also review the literature on the complications of APC treatment. PMID:23162622

  19. Dosimetry audit simulation of treatment planning system in multicenters radiotherapy

    NASA Astrophysics Data System (ADS)

    Kasmuri, S.; Pawiro, S. A.

    2017-07-01

    Treatment Planning System (TPS) is an important modality that determines radiotherapy outcome. TPS requires input data obtained through commissioning and the potentially error occurred. Error in this stage may result in the systematic error. The aim of this study to verify the TPS dosimetry to know deviation range between calculated and measurement dose. This study used CIRS phantom 002LFC representing the human thorax and simulated all external beam radiotherapy stages. The phantom was scanned using CT Scanner and planned 8 test cases that were similar to those in clinical practice situation were made, tested in four radiotherapy centers. Dose measurement using 0.6 cc ionization chamber. The results of this study showed that generally, deviation of all test cases in four centers was within agreement criteria with average deviation about -0.17±1.59 %, -1.64±1.92 %, 0.34±1.34 % and 0.13±1.81 %. The conclusion of this study was all TPS involved in this study showed good performance. The superposition algorithm showed rather poor performance than either analytic anisotropic algorithm (AAA) and convolution algorithm with average deviation about -1.64±1.92 %, -0.17±1.59 % and -0.27±1.51 % respectively.

  20. Randomized comparisons of radiotherapy and nitrosoureas for the treatment of malignant glioma after surgery

    SciTech Connect

    Walker, M.D.; Green, S.B.; Byar, D.P.

    1980-12-04

    Within three weeks of definitive surgical intervention, 467 patients with histologically proved malignant glioma were randomized to receive one of four treatment regimens: semustine (MeCCNU), radiotherapy, carmustine (BCNU) plus radiotherapy, or semustine plus radiotherapy. We analyzed the data for the total randomized population and for the 358 patients in whom the initial protocol specifications were met (the valid study group). Observed toxicity included acceptable skin reactions secondary to radiotherapy and reversible leukopenia and thrombocytopenia due to chemotherapy. Radiotherapy used alone or in combination with a nitrosourea significantly improved survival in comparison with semustine alone. The group receiving carmustine plus radiotherapy had the best survival, but the difference in survival between the groups receiving carmustine plus radiotherapy and semustine plus radiotherapy was not statistically significant. The combination of carmustine plus radiotherapy produced a modest benefit in long-term (18-month) survival as compared with radiotherapy alone, although the difference between survival curves was not significant at the 0.05 level. This study suggests that it is best to use radiotherapy in the post-surgical treatment of malignant glioma and to continue the search for an effective chemotherapeutic regimen to use in addition to radiotherapy.

  1. The Efficacy of Radiotherapy in the Treatment of Orbital Pseudotumor

    SciTech Connect

    Matthiesen, Chance; Bogardus, Carl; Thompson, J. Spencer; Farris, Bradley; Hildebrand, Lloyd; Wilkes, Byron; Syzek, Elizabeth; Algan, Ozer; Ahmad, Salahuddin; Herman, Terence

    2011-04-01

    Purpose: To review institutional outcomes for patients treated with external-beam radiotherapy (EBRT) for orbital pseudotumor. Methods and Materials: This is a single-institution retrospective review of 20 orbits in 16 patients diagnosed with orbital pseudotumor that received EBRT at the University of Oklahoma, Department of Radiation Oncology. Treated patients had a median follow-up of 16.5 months. Results: Fifteen patients (93.7%) were initially treated with corticosteroids. Eight had recurrence after steroid cessation, six were unable to taper corticosteroids completely or partially, and one experienced progression of symptoms despite corticosteroid therapy. Fourteen patients (87.5%) initially responded to radiotherapy indicated by clinical improvement of preradiation symptoms and/or tapering of corticosteroid dose. Mean EBRT dose was 20 Gy (range, 14-30 Gy). Thirteen patients (81.2%) continued to improve after radiation therapy. Patient outcomes were complete cessation of corticosteroid therapy in nine patients (56.3%) and reduced corticosteroid dose in four patients (25%). Radiotherapy did not achieve long-term control for three patients (18.7%), who still required preradiation corticosteroid dosages. Three patients received retreatment(s) of four orbits, of which two patients achieved long-term symptom control without corticosteroid dependence. One patient received retreatment to an orbit three times, achieving long-term control without corticosteroid dependence. No significant late effects have been observed in retreated patients. Conclusions: Radiotherapy is an effective treatment for acute symptomatic improvement and long-term control of orbital pseudotumor. Orbital retreatment can be of clinical benefit, without apparent increase in morbidity, when initial irradiation fails to achieve complete response.

  2. Multi-energy imagers for a radiotherapy treatment environment

    NASA Astrophysics Data System (ADS)

    Antonuk, Larry E.; Liu, Langechuan; Liang, Albert K.; El-Mohri, Youcef; Zhao, Qihua; Koniczek, Martin; Jiang, Hao

    2015-03-01

    Over the last ~15 years, the central goal in external beam radiotherapy of maximizing dose to the tumor while minimizing dose to surrounding normal tissues has been greatly facilitated by the development and clinical implementation of many innovations. These include megavoltage active matrix flat-panel imagers (MV AMFPIs) designed to image the treatment beam, and separate kilovoltage (kV) AMFPIs and x-ray sources designed to provide high-contrast projection and cone-beam CT images in the treatment room. While these systems provide clinically valuable information, a variety of advantages would accrue through introduction of the capability to produce clinically useful, high quality imaging information at multiple energies (e.g., kV and MV) from a single detector along the treatment beam direction. One possible approach for achieving this goal involves substitution of the x-ray converters used in conventional MV AMFPIs with thick, segmented crystalline scintillators designed for dual-energy operation, coupled with the addition of x-ray imaging beams that contain a significant diagnostic component. A second approach involves introduction of a large area, monolithic array of photon counting pixels with multiple energy thresholds and event counters, which could provide multi-spectral views of the treatment beam with improved contrast. In this paper, the motivations behind, and the merits of each approach are described. In addition, prospects for such dual-energy imagers and photon counting array designs are discussed in the context of the radiotherapy environment.

  3. Clinical application of multimodality imaging in radiotherapy treatment planning for rectal cancer.

    PubMed

    Wang, Yan Yang; Zhe, Hong

    2013-12-11

    Radiotherapy plays an important role in the treatment of rectal cancer. Three-dimensional conformal radiotherapy and intensity-modulated radiotherapy are mainstay techniques of radiotherapy for rectal cancer. However, the success of these techniques is heavily reliant on accurate target delineation and treatment planning. Computed tomography simulation is a cornerstone of rectal cancer radiotherapy, but there are limitations, such as poor soft-tissue contrast between pelvic structures and partial volume effects. Magnetic resonance imaging and positron emission tomography (PET) can overcome these limitations and provide additional information for rectal cancer treatment planning. PET can also reduce the interobserver variation in the definition of rectal tumor volume. However, there is a long way to go before these image modalities are routinely used in the clinical setting. This review summarizes the most promising studies on clinical applications of multimodality imaging in target delineation and treatment planning for rectal cancer radiotherapy.

  4. Dosimetric inter-institutional comparison in European radiotherapy centres: Results of IAEA supported treatment planning system audit.

    PubMed

    Gershkevitsh, Eduard; Pesznyak, Csilla; Petrovic, Borislava; Grezdo, Joseph; Chelminski, Krzysztof; do Carmo Lopes, Maria; Izewska, Joanna; Van Dyk, Jacob

    2014-05-01

    One of the newer audit modalities operated by the International Atomic Energy Agency (IAEA) involves audits of treatment planning systems (TPS) in radiotherapy. The main focus of the audit is the dosimetry verification of the delivery of a radiation treatment plan for three-dimensional (3D) conformal radiotherapy using high energy photon beams. The audit has been carried out in eight European countries - Estonia, Hungary, Latvia, Lithuania, Serbia, Slovakia, Poland and Portugal. The corresponding results are presented. The TPS audit reviews the dosimetry, treatment planning and radiotherapy delivery processes using the 'end-to-end' approach, i.e. following the pathway similar to that of the patient, through imaging, treatment planning and dose delivery. The audit is implemented at the national level with IAEA assistance. The national counterparts conduct the TPS audit at local radiotherapy centres through on-site visits. TPS calculated doses are compared with ion chamber measurements performed in an anthropomorphic phantom for eight test cases per algorithm/beam. A set of pre-defined agreement criteria is used to analyse the performance of TPSs. TPS audit was carried out in 60 radiotherapy centres. In total, 190 data sets (combination of algorithm and beam quality) have been collected and reviewed. Dosimetry problems requiring interventions were discovered in about 10% of datasets. In addition, suboptimal beam modelling in TPSs was discovered in a number of cases. The TPS audit project using the IAEA methodology has verified the treatment planning system calculations for 3D conformal radiotherapy in a group of radiotherapy centres in Europe. It contributed to achieving better understanding of the performance of TPSs and helped to resolve issues related to imaging, dosimetry and treatment planning.

  5. Role of Radiotherapy and Newer Techniques in the Treatment of GI Cancers.

    PubMed

    Hajj, Carla; Goodman, Karyn A

    2015-06-01

    The role of radiotherapy in multidisciplinary treatment of GI malignancies is well established. Recent advances in imaging as well as radiotherapy planning and delivery techniques have made it possible to target tumors more accurately while sparing normal tissues. Intensity-modulated radiotherapy is an advanced method of delivering radiation using cutting-edge technology to manipulate beams of radiation. The role of intensity-modulated radiotherapy is growing for many GI malignancies, such as cancers of the stomach, pancreas, esophagus, liver, and anus. Stereotactic body radiotherapy is an emerging treatment option for some GI tumors such as locally advanced pancreatic cancer and primary or metastatic tumors of the liver. Stereotactic body radiotherapy requires a high degree of confidence in tumor location and subcentimeter accuracy of the delivered dose. New image-guided techniques have been developed to overcome setup uncertainties at the time of treatment, including real-time imaging on the linear accelerator. Modern imaging techniques have also allowed for more accurate pretreatment staging and delineation of the primary tumor and involved sites. In particular, magnetic resonance imaging and positron emission tomography scans can be particularly useful in radiotherapy planning and assessing treatment response. Molecular biomarkers are being investigated as predictors of response to radiotherapy with the intent of ultimately moving toward using genomic and proteomic determinants of therapeutic strategies. The role of all of these new approaches in the radiotherapeutic management of GI cancers and the evolving role of radiotherapy in these tumor sites will be highlighted in this review.

  6. The NUKDOS software for treatment planning in molecular radiotherapy.

    PubMed

    Kletting, Peter; Schimmel, Sebastian; Hänscheid, Heribert; Luster, Markus; Fernández, Maria; Nosske, Dietmar; Lassmann, Michael; Glatting, Gerhard

    2015-09-01

    The aim of this work was the development of a software tool for treatment planning prior to molecular radiotherapy, which comprises all functionality to objectively determine the activity to administer and the pertaining absorbed doses (including the corresponding error) based on a series of gamma camera images and one SPECT/CT or probe data. NUKDOS was developed in MATLAB. The workflow is based on the MIRD formalism For determination of the tissue or organ pharmacokinetics, gamma camera images as well as probe, urine, serum and blood activity data can be processed. To estimate the time-integrated activity coefficients (TIAC), sums of exponentials are fitted to the time activity data and integrated analytically. To obtain the TIAC on the voxel level, the voxel activity distribution from the quantitative 3D SPECT/CT (or PET/CT) is used for scaling and weighting the TIAC derived from the 2D organ data. The voxel S-values are automatically calculated based on the voxel-size of the image and the therapeutic nuclide ((90)Y, (131)I or (177)Lu). The absorbed dose coefficients are computed by convolution of the voxel TIAC and the voxel S-values. The activity to administer and the pertaining absorbed doses are determined by entering the absorbed dose for the organ at risk. The overall error of the calculated absorbed doses is determined by Gaussian error propagation. NUKDOS was tested for the operation systems Windows(®) 7 (64 Bit) and 8 (64 Bit). The results of each working step were compared to commercially available (SAAMII, OLINDA/EXM) and in-house (UlmDOS) software. The application of the software is demonstrated using examples form peptide receptor radionuclide therapy (PRRT) and from radioiodine therapy of benign thyroid diseases. For the example from PRRT, the calculated activity to administer differed by 4% comparing NUKDOS and the final result using UlmDos, SAAMII and OLINDA/EXM sequentially. The absorbed dose for the spleen and tumour differed by 7% and 8

  7. What is changing in radiotherapy for the treatment of locally advanced nonsmall cell lung cancer patients? A review.

    PubMed

    Giaj-Levra, Niccoló; Ricchetti, Francesco; Alongi, Filippo

    2016-01-01

    Radiotherapy treatment continues to have a relevant impact in the treatment of nonsmall cell cancer (NSCLC). Use of concurrent chemotherapy and radiotherapy is considered the gold standard in the treatment of locally advanced NSCLC but clinical outcomes are not satisfactory. Introduction of new radiotherapy technology and chemotherapy regimens are under investigation in this setting with the goal to improve unsatisfactory results. We report how radiotherapy is changing in the treatment of locally advanced NSCLC.

  8. Role of intraoperative radiotherapy in the treatment of sacral chordoma.

    PubMed

    Jullien-Petrelli, A C; Asencio, J M; Orue-Echebarria, M I; Lozano, P; Álvarez, A; Serrano, J; Calvo, F M; Calvo-Haro, J A; Lasso, J M; García-Sabrido, J L

    2017-09-04

    Sacral chordoma is a rare entity with high local recurrence rates when complete resection is not achieved. Till date, there are not any series available in literature combining surgery and intraoperative radiotherapy (IORT). To report the experience of our Centre in the management of sacral chordoma combining radical resection with both external radiotherapy and intraoperative radiotherapy (IORT). Retrospective case series. 15 patients with sacral chordoma resected in our centre from 1998 to 2015. Overall survival (OS), Disease free survival and rates of local and distant recurrence. We retrospectively revised the records of all the patients with sacral chordoma resected in our centre from 1998 to December 2015. Overall survival (OS), Disease free survival and rates of local and distant recurrence were calculated. Results between patients treated with or without IORT were compared. A total of 15 patients were identified: 8 males and 7 females. Median age was 59 years (range 28-77). IORT was applied in 9 patients and 6 were treated with surgical resection without IORT. In 13 patients we performed the treatment of the primary tumor and in 2 patients we performed the treatment of recurrence disease. A posterior approach was used in 4 patients. Wide surgical margins (R0) were achieved in 6 patients, marginal margins (R1) in 7 patients and there were not any patient with intralesional (R2) margins. At a median follow up of 38 months (range 11-209 months), the 5 years OS in the IORT group was 100% versus 53% in the group of non-IORT (p=0.05). The median DFS in the IORT group was 85 months versus 41 months in the non-IORT group. In the group without IORT, two patients died and nobody died during the follow up in the group treated with IORT. High sacrectomy treated patients had a median survival of 41 months versus 90 months in low sacrectomy treated patients. DFS in patients without gluteal involvement was 100% at 5 years, and 40% in patients with gluteal involvement (fig

  9. Development and clinical introduction of automated radiotherapy treatment planning for prostate cancer

    NASA Astrophysics Data System (ADS)

    Winkel, D.; Bol, G. H.; van Asselen, B.; Hes, J.; Scholten, V.; Kerkmeijer, L. G. W.; Raaymakers, B. W.

    2016-12-01

    To develop an automated radiotherapy treatment planning and optimization workflow to efficiently create patient specifically optimized clinical grade treatment plans for prostate cancer and to implement it in clinical practice. A two-phased planning and optimization workflow was developed to automatically generate 77Gy 5-field simultaneously integrated boost intensity modulated radiation therapy (SIB-IMRT) plans for prostate cancer treatment. A retrospective planning study (n  =  100) was performed in which automatically and manually generated treatment plans were compared. A clinical pilot (n  =  21) was performed to investigate the usability of our method. Operator time for the planning process was reduced to  <5 min. The retrospective planning study showed that 98 plans met all clinical constraints. Significant improvements were made in the volume receiving 72Gy (V72Gy) for the bladder and rectum and the mean dose of the bladder and the body. A reduced plan variance was observed. During the clinical pilot 20 automatically generated plans met all constraints and 17 plans were selected for treatment. The automated radiotherapy treatment planning and optimization workflow is capable of efficiently generating patient specifically optimized and improved clinical grade plans. It has now been adopted as the current standard workflow in our clinic to generate treatment plans for prostate cancer.

  10. Erythema multiforme after radiotherapy with aromatase inhibitor administration in breast-conservation treatment for breast cancer.

    PubMed

    Nakatani, Kimiko; Matsumoto, Masaaki; Ue, Hironobu; Nishioka, Akihito; Tanaka, Yousuke; Kodama, Hajime; Sasaguri, Shiro; Ogawa, Yasuhiro

    2008-01-01

    Generalized eruptions associated with radiotherapy such as erythema multiforme (EM), Steven-Johnson syndrome and toxic epidermal necrolysis are uncommon reactions. A few cases of generalized eruptions during and after radiotherapy have been reported with the use of anticonvulsants and anticancer drugs. However, no reports have described mucocutaneous reactions associated with radiotherapy and concurrent use of anastrozole, an aromatase inhibitor. This report describes EM occurring after radiotherapy performed during breast-conserving treatment for breast cancer in a patient who was taking oral anastrozole.

  11. Development of Advanced Multi-Modality Radiation Treatment Planning Software for Neutron Radiotherapy and Beyond

    SciTech Connect

    Nigg, D; Wessol, D; Wemple, C; Harkin, G; Hartmann-Siantar, C

    2002-08-20

    The Idaho National Engineering and Environmental Laboratory (INEEL) has long been active in development of advanced Monte-Carlo based computational dosimetry and treatment planning methods and software for advanced radiotherapy, with a particular focus on Neutron Capture Therapy (NCT) and, to a somewhat lesser extent, Fast-Neutron Therapy. The most recent INEEL software system of this type is known as SERA, Simulation Environment for Radiotherapy Applications. As a logical next step in the development of modern radiotherapy planning tools to support the most advanced research, INEEL and Lawrence Livermore National Laboratory (LLNL), the developers of the PEREGRTNE computational engine for radiotherapy treatment planning applications, have recently launched a new project to collaborate in the development of a ''next-generation'' multi-modality treatment planning software system that will be useful for all modern forms of radiotherapy.

  12. Intensity-modulated radiotherapy for neoadjuvant treatment of gastric cancer

    SciTech Connect

    Knab, Brian; Rash, Carla; Farrey, Karl; Jani, Ashesh B. . E-mail: jani@rover.uchicago.edu

    2006-01-01

    Radiation therapy plays an integral role in the treatment of gastric cancer in the postsurgery setting, the inoperable/palliative setting, and, as in the case of the current report, in the setting of neoadjuvant therapy prior to surgery. Typically, anterior-posterior/posterior-anterior (AP/PA) or 3-field techniques are used. In this report, we explore the use of intensity-modulated radiotherapy (IMRT) treatment in a patient whose care was transferred to our institution after 3-field radiotherapy (RT) was given to a dose of 30 Gy at an outside institution. If the 3-field plan were continued to 50 Gy, the volume of irradiated liver receiving greater than 30 Gy would have been unacceptably high. To deliver the final 20 Gy, an opposed parallel AP/PA plan and an IMRT plan were compared to the initial 3-field technique for coverage of the target volume as well as dose to the kidneys, liver, small bowel, and spinal cord. Comparison of the 3 treatment techniques to deliver the final 20 Gy revealed reduced median and maximum dose to the whole kidney with the IMRT plan. For this 20-Gy boost, the volume of irradiated liver was lower for both the IMRT plan and the AP/PA plan vs. the 3-field plan. Comparing the IMRT boost plan to the AP/PA boost-dose range (<10 Gy) in comparison to the AP/PA plan; however, the IMRT plan irradiated a smaller liver volume within the higher dose region (>10 Gy) in comparison to the AP/PA plan. The IMRT boost plan also irradiated a smaller volume of the small bowel compared to both the 3-field plan and the AP/PA plan, and also delivered lower dose to the spinal cord in comparison to the AP/PA plan. Comparison of the composite plans revealed reduced dose to the whole kidney using IMRT. The V20 for the whole kidney volume for the composite IMRT plan was 30% compared to approximately 60% for the composite AP/PA plan. Overall, the dose to the liver receiving greater than 30 Gy was lower for the composite IMRT plan and was well below acceptable limits

  13. Precision, high dose radiotherapy: helium ion treatment of uveal melanoma

    SciTech Connect

    Saunders, W.M.; Char, D.H.; Quivey, J.M.; Castro, J.R.; Chen, G.T.Y.; Collier, J.M.; Cartigny, A.; Blakely, E.A.; Lyman, J.T.; Zink, S.R.

    1985-02-01

    The authors report on 75 patients with uveal melanoma who were treated by placing the Bragg peak of a helium ion beam over the tumor volume. The technique localizes the high dose region very tightly around the tumor volume. This allows critical structures, such as the optic disc and the macula, to be excluded from the high dose region as long as they are 3 to 4 mm away from the edge of the tumor. Careful attention to tumor localization, treatment planning, patient immobilization and treatment verification is required. With a mean follow-up of 22 months (3 to 60 months) the authors have had only five patients with a local recurrence, all of whom were salvaged with another treatment. Pretreatment visual acuity has generally been preserved as long as the tumor edge is at least 4 mm away from the macula and optic disc. The only serious complication to date has been an 18% incidence of neovascular glaucoma in the patients treated at our highest dose level. Clinical results and details of the technique are presented to illustrate potential clinical precision in administering high dose radiotherapy with charged particles such as helium ions or protons.

  14. Multimodality treatment with radiotherapy for huge hepatocellular carcinoma.

    PubMed

    Han, Hee Ji; Kim, Mi Sun; Cha, Jihye; Choi, Jin Sub; Han, Kwang Hyub; Seong, Jinsil

    2014-01-01

    For huge hepatocellular carcinoma (HCC), therapeutic decisions have varied from local therapy to systemic therapy, with radiotherapy (RT) playing only a palliative role. In this study, we investigated whether multimodality treatment involving RT could be effective in huge HCC. This study was performed in 116 patients with HCC >10 cm. The number of patients in stage II, III and IV was 12, 54 and 50, respectively. RT was given as a combined modality in most patients. The median dose was 45 Gy, with 1.8 Gy per fraction. The median overall survival (OS) and progression-free survival (PFS) were 14.8 and 6.5 months, respectively. The median infield PFS was not reached. Infield failure, outfield intrahepatic and extrahepatic failure were observed in 8.6, 18.1, and 12.1% of patients, respectively. For OS and PFS, number of tumors, initial alpha-fetoprotein (AFP) level, treatment response, percent AFP decrement, and hepatic resection were significant prognostic factors. Tumor characteristics and treatment response were significantly different between long-term survivors and the other patients. Although huge HCC presents an aggressive clinical course, multimodality approaches involving RT can offer an opportunity for prolonged survival. © 2014 S. Karger AG, Basel.

  15. External beam radiotherapy as curative treatment of prostate cancer.

    PubMed

    Pisansky, Thomas M

    2005-07-01

    External beam radiotherapy (RT) has been used as a curative treatment of prostate cancer for more than 5 decades, with the "modern" era emerging more than 3 decades ago. Its history is marked by gradual improvements punctuated by several quantum leaps that are increasingly driven by advancements in the computer and imaging sciences and by its integration with complementary forms of treatment. Consequently, the contemporary use of external beam RT barely resembles its earliest form, and this must be appreciated in the context of current patient care. The influence of predictive factors on the use and outcomes of external beam RT is presented, as is a selected review of the methods and outcomes of external beam RT as a single therapeutic intervention, in association with androgen suppression, or as a postoperative adjunct. Thus, the "state of the (radiotherapeutic) art" is presented to enhance the understanding of this treatment approach with the hope that this information will serve as a useful resource to physicians as they care for patients with prostate cancer.

  16. Squamous-cell carcinoma of the anus: progress in radiotherapy treatment.

    PubMed

    Glynne-Jones, Rob; Tan, David; Hughes, Robert; Hoskin, Peter

    2016-07-01

    Chemoradiotherapy is the standard-of-care treatment of squamous-cell carcinoma of the anus (SCCA), and this has not changed in decades. Radiation doses of 50-60 Gy, as used in many phase III trials, result in substantial late morbidities and fail to control larger and node-positive tumours. Technological advances in radiation therapy are improving patient outcomes and quality of life, and should be applied to patients with SCCA. Modern techniques such as intensity-modulated radiotherapy (IMRT), rotational IMRT, image-guided radiotherapy using cone-beam CT, and stereotactic techniques have enabled smaller margins and highly conformal plans, resulting in decreased radiation doses to the organs at risk and ensuring a shorter overall treatment time. In this Perspectives article, the use of novel approaches to target delineation, optimized radiotherapy techniques, adaptive radiotherapy, dose-escalation with external-beam radiotherapy (EBRT) or brachytherapy, and the potential for modified fractionation are discussed in the context of SCCA.

  17. [Development of an educational program starting from a process approach in a department of radiotherapy].

    PubMed

    Lenaerts, E; Delgaudine, M; Coucke, P

    2014-01-01

    In order to be able to implement technological evolution and organizational changes on a regular and continuous manner, the radiotherapy department initiated in 2007 a comprehensive policy of operational risk management and overall quality program. The leadership in the department is convinced that the management of professional skills is mandatory to implement rapidly new treatment techniques while simultaneously assuring a high level of quality for patient care. The "process approach" is based on a comprehensive description of all the processes building up the organization in order to check how every single process contributes to patient satisfaction. This kind of approach allows an enhanced visibility on the functioning of the department, a better control on the inter-individual relations, both between different professional groups among caregivers and between those latter and the patients. This approach yields a view on the gain obtained with each single process and leads to identification of failures in safety barriers. The process approach identifies the required professional skills in order to guarantee a high quality of care. This has resulted in the development of a training program tailored to the needs of a radiotherapy department. This training program has recently been submitted and validated by the university authorities and is nowadays registered as a certificate at the university of Liège.

  18. Monitor Unit Checking in Heterogeneous Stereotactic Body Radiotherapy Treatment Planning

    SciTech Connect

    Higgins, Patrick D.; Adolfson, Troy; Cho, L. Chinsoo; Saxena, Rishik

    2011-10-01

    Treatment of lung cancer using very-high-dose fractionation in small fields requires well-tested dose modeling, a method for density-averaging compound targets constructed from different parts of the breathing cycle, and monitor unit verification of the heterogeneity-corrected treatment plans. The quality and safety of each procedure are dependent on these factors. We have evaluated the dosimetry of our first 26 stereotactic body radiotherapy (SBRT) patients, including 260 treatment fields, planned with the Pinnacle treatment planning system. All targets were combined from full expiration and inspiration computed tomography scans and planned on the normal respiration scan with 6-MV photons. Combined GTVs (cGTVs) have been density-averaged in different ways for comparison of the effect on total monitor units. In addition, we have compared planned monitor units against hand calculations using 2 classic 1D correction methods: (1) effective attenuation and (2) ratio of Tissue-Maximum Ratios (TMRs) to determine the range of efficacy of simple verification methods over difficult-to-perform measurements. Different methods of density averaging for combined targets have been found to have minimal impact on total dose as evidenced by the range of total monitor units generated for each method. Nondensity-corrected treatment plans for the same fields were found to require about 8% more monitor units on average. Hand calculations, using the effective attenuation method were found to agree with Pinnacle calculations for nonproblematic fields to within {+-}10% for >95% of the fields tested. The ratio of TMRs method was found to be unacceptable. Reasonable choices for density-averaging of cGTVs using full inspiration/expiration scans should not strongly affect the planning dose. Verification of planned monitor units, as a check for problematic fields, can be done for 6-MV fields with simple 1D effective attenuation-corrected hand calculations.

  19. [The hypofractionated radiotherapy in the treatment of the prostate cancer: radiate less to treat more].

    PubMed

    Boissier, R; Gross, E

    2010-05-01

    The principle of the hypofractionation in radiotherapy is to deliver a higher dose by session and to reduce the duration of treatment. In the particular case of the cancer of prostate, a hypofractionned protocol allows to deliver an equivalent radiobiological dose identical even higher than a standard plan of irradiation. The hypofractionation is presented as a solution to improve the access to the care (fewer processing times by patient, more patients treated by machine) while increasing the quality of the care: better carcinologic control, less radiotoxicity. The objective of this article is to make a clarification on the hypofractionned radiotherapy in first intention in the treatment of the localized prostate cancer. We count three studies on large cohorts, comparing standard plans to 1.8-2 Gy/session and hypofractionned plans (2.5-3 Gy/session). The inferior carcinologic results of the two first comparative studies with regard to the study of phase I/II of the Cleveland clinic were owed to a sub-dosage of hypofractionned plans. The administered equivalent biological doses were lower than the at present recommended total doses and lower than the theoretical doses, calculated on the bases of an erroneous evaluation of the radiosensibility of the prostate cancer. In the comparative study of Arcangeli, the rate of survival without biological recurrence in 4 years (82%) was significantly to the advantage of the hypofractionned group, while reducing the duration of treatment of 3 weeks. Four comparative studies reported aigues/late toxicity, gastrointestinal (GI)/genito-urinary acceptable (GU) even lower with a hypofractionned plan. The hypofractionation is potentially the future of the radiotherapy in the treatment of the localized prostate cancer thanks to the technological innovation, but for all that does not constitute at present a standard.

  20. Retrieval with Clustering in a Case-Based Reasoning System for Radiotherapy Treatment Planning

    NASA Astrophysics Data System (ADS)

    Khussainova, Gulmira; Petrovic, Sanja; Jagannathan, Rupa

    2015-05-01

    Radiotherapy treatment planning aims to deliver a sufficient radiation dose to cancerous tumour cells while sparing healthy organs in the tumour surrounding area. This is a trial and error process highly dependent on the medical staff's experience and knowledge. Case-Based Reasoning (CBR) is an artificial intelligence tool that uses past experiences to solve new problems. A CBR system has been developed to facilitate radiotherapy treatment planning for brain cancer. Given a new patient case the existing CBR system retrieves a similar case from an archive of successfully treated patient cases with the suggested treatment plan. The next step requires adaptation of the retrieved treatment plan to meet the specific demands of the new case. The CBR system was tested by medical physicists for the new patient cases. It was discovered that some of the retrieved cases were not suitable and could not be adapted for the new cases. This motivated us to revise the retrieval mechanism of the existing CBR system by adding a clustering stage that clusters cases based on their tumour positions. A number of well-known clustering methods were investigated and employed in the retrieval mechanism. Results using real world brain cancer patient cases have shown that the success rate of the new CBR retrieval is higher than that of the original system.

  1. Prostate Bed Motion During Intensity-Modulated Radiotherapy Treatment

    SciTech Connect

    Klayton, Tracy; Price, Robert; Buyyounouski, Mark K.; Sobczak, Mark; Greenberg, Richard; Li, Jinsheng; Keller, Lanea; Sopka, Dennis; Kutikov, Alexander; Horwitz, Eric M.

    2012-09-01

    Purpose: Conformal radiation therapy in the postprostatectomy setting requires accurate setup and localization of the prostatic fossa. In this series, we report prostate bed localization and motion characteristics, using data collected from implanted radiofrequency transponders. Methods and Materials: The Calypso four-dimensional localization system uses three implanted radiofrequency transponders for daily target localization and real-time tracking throughout a course of radiation therapy. We reviewed the localization and tracking reports for 20 patients who received ultrasonography-guided placement of Calypso transponders within the prostate bed prior to a course of intensity-modulated radiation therapy at Fox Chase Cancer Center. Results: At localization, prostate bed displacement relative to bony anatomy exceeded 5 mm in 9% of fractions in the anterior-posterior (A-P) direction and 21% of fractions in the superior-inferior (S-I) direction. The three-dimensional vector length from skin marks to Calypso alignment exceeded 1 cm in 24% of all 652 fractions with available setup data. During treatment, the target exceeded the 5-mm tracking limit for at least 30 sec in 11% of all fractions, generally in the A-P or S-I direction. In the A-P direction, target motion was twice as likely to move posteriorly, toward the rectum, than anteriorly. Fifteen percent of all treatments were interrupted for repositioning, and 70% of patients were repositioned at least once during their treatment course. Conclusion: Set-up errors and motion of the prostatic fossa during radiotherapy are nontrivial, leading to potential undertreatment of target and excess normal tissue toxicity if not taken into account during treatment planning. Localization and real-time tracking of the prostate bed via implanted Calypso transponders can be used to improve the accuracy of plan delivery.

  2. [What is the role of intraoperative radiotherapy in breast cancer treatment?].

    PubMed

    Aumont, M

    2016-10-01

    Breast-conserving surgery followed by whole breast postoperative irradiation is considered to be the current standard treatment for patients with early stage breast cancer. It allows an excellent local tumour control with 6% of local recurrence. Over the last years, partial breast radiotherapy has been developed to reduce treatment volume and duration. Intraoperative radiotherapy is one of the techniques. It offers an excellent delineation of the tumour bed and high normal tissue sparing. This purpose of this review is to describe the different intraoperative radiotherapy techniques available, to assess their potential clinical efficiency and tolerance, the recommendations for new practice with a selected population of patients and for future research.

  3. Adjuvant treatment for Stage I seminoma: Why radiotherapy is better than carboplatin.

    PubMed

    Yathiraj, Prahlad H; Sharan, Krishna; Fernandes, Donald J; Vidyasagar, M S

    2016-01-01

    Adjuvant treatment options for Stage I seminoma include active surveillance, chemotherapy, and radiotherapy. Active surveillance may not be ideal for the average Indian patient. Of the two accepted adjuvant therapy options, namely single-dose carboplatin chemotherapy and radiotherapy to the retroperitoneal nodes, though it intuitively appears more appealing, a deeper review reveals the potential drawbacks of chemotherapy. This article highlights the misconceptions regarding carboplatin and provides reasons for an argument why radiotherapy is better when a patient with Stage I seminoma chooses to undergo adjuvant treatment.

  4. [Post-radiotherapy telangiectasias. Treatment with pulsed-dye laser. Sequential histological studies].

    PubMed

    Ruiz-Genao, Diana P; Córdoba, Susana; García-F-Villalta, Maria José; Dorado, José Maria; Fernández-Herrera, Jesús

    2006-06-01

    Chronic radiodermatitis after radiotherapy is a frequent sequela that may be worrying for the patient. Few cases have been published in the literature in which pulsed-dye laser has been used in the treatment of telangiectasias that appeared after radiotherapy for breast cancer. We present a female patient with radiodermatitis on the neck after radiotherapy for nasopharyngeal carcinoma. The patient received five sessions of pulsed-dye laser treatment (3 ms pulse duration, 7 mm spot size, fluence between 7 and 12 J/cm 2). Sequential histological studies were performed. The response to treatment was very good, with the lesions almost completely disappearing. The patient was very satisfied with the result. Pulsed-dye laser is a safe and effective treatment for chronic radiodermatitis of the neck after radiotherapy.

  5. Linear programming based on neural networks for radiotherapy treatment planning.

    PubMed

    Wu, X; Zhu, Y; Luo, L

    2000-03-01

    In this paper, we propose a neural network model for linear programming that is designed to optimize radiotherapy treatment planning (RTP). This kind of neural network can be easily implemented by using a kind of 'neural' electronic system in order to obtain an optimization solution in real time. We first give an introduction to the RTP problem and construct a non-constraint objective function for the neural network model. We adopt a gradient algorithm to minimize the objective function and design the structure of the neural network for RTP. Compared to traditional linear programming methods, this neural network model can reduce the time needed for convergence, the size of problems (i.e., the number of variables to be searched) and the number of extra slack and surplus variables needed. We obtained a set of optimized beam weights that result in a better dose distribution as compared to that obtained using the simplex algorithm under the same initial condition. The example presented in this paper shows that this model is feasible in three-dimensional RTP.

  6. Perspectives in Medical Applications of Monte Carlo Simulation Software for Clinical Practice in Radiotherapy Treatments

    NASA Astrophysics Data System (ADS)

    Boschini, Matteo; Giani, Simone; Ivanchenko, Vladimir; Rancoita, Pier-Giorgio

    2006-04-01

    We discuss the physics requirements to accurately model radiation dosimetry in the human body as performed for oncological radiotherapy treatment. Recent advancements in computing hardware and software simulation technology allow precise dose calculation in real-life imaging output, with speed suitable for clinical needs. An experimental programme, based on physics published literature, is proposed to demonstrate the actual possibility to improve the precision of radiotherapy treatment planning.

  7. Radiotherapy for Esthesioneuroblastoma: Is Elective Nodal Irradiation Warranted in the Multimodality Treatment Approach?

    SciTech Connect

    Noh, O Kyu; Lee, Sang-wook; Yoon, Sang Min; Kim, Sung Bae; Kim, Sang Yoon; Kim, Chang Jin; Jo, Kyung Ja; Choi, Eun Kyung; Song, Si Yeol; Kim, Jong Hoon; Ahn, Seung Do

    2011-02-01

    Purpose: The role of elective nodal irradiation (ENI) in radiotherapy for esthesioneuroblastoma (ENB) has not been clearly defined. We analyzed treatment outcomes of patients with ENB and the frequency of cervical nodal failure in the absence of ENI. Methods and Materials: Between August 1996 and December 2007, we consulted with 19 patients with ENB regarding radiotherapy. Initial treatment consisted of surgery alone in 2 patients; surgery and postoperative radiotherapy in 4; surgery and adjuvant chemotherapy in 1; surgery, postoperative radiotherapy, and chemotherapy in 3; and chemotherapy followed by radiotherapy or concurrent chemoradiotherapy in 5. Five patients did not receive planned radiotherapy because of disease progression. Including 2 patients who received salvage radiotherapy, 14 patients were treated with radiotherapy. Elective nodal irradiation was performed in 4 patients with high-risk factors, including 3 with cervical lymph node metastasis at presentation. Results: Fourteen patients were analyzable, with a median follow-up of 27 months (range, 7-64 months). The overall 3-year survival rate was 73.4%. Local failure occurred in 3 patients (21.4%), regional cervical failure in 3 (21.4%), and distant failure in 2 (14.3%). No cervical nodal failure occurred in patients treated with combined systemic chemotherapy regardless of ENI. Three cervical failures occurred in the 4 patients treated with ENI or neck dissection (75%), none of whom received systemic chemotherapy. Conclusions: ENI during radiotherapy for ENB seems to play a limited role in preventing cervical nodal failure. Omitting ENI may be an option if patients are treated with a combination of radiotherapy and chemotherapy.

  8. Role of Radiotherapy as Curative Treatment of Extramammary Paget's Disease

    SciTech Connect

    Hata, Masaharu; Omura, Motoko; Koike, Izumi; Wada, Hidefumi; Miyagi, Etsuko; Tayama, Yoshibumi; Odagiri, Kazumasa; Minagawa, Yumiko; Ogino, Ichiro; Inoue, Tomio

    2011-05-01

    Purpose: Extramammary Paget's disease (EMPD) is a relatively rare malignancy that usually arises in the genital areas. Wide surgical excision remains the standard and most reliable curative treatment of EMPD. However, surgery is sometimes not possible, because many patients are elderly, and complete excision can be difficult owing to the tumor location. We, therefore, performed a review to determine the role of radiotherapy (RT) for EMPD. Methods and Materials: A total of 22 patients with EMPD in their external genitalia (4 men and 18 women, age 52-94 years at RT) underwent RT with curative intent. Nine patients had regional lymph node metastases. A total dose of 45-70.2 Gy (median, 60) was delivered to the pelvis, including the tumors, in 25-39 fractions (median, 33). Results: In all but 3 patients, the irradiated tumors were controlled during a follow-up period of 8-133 months (median, 42). Of the 22 patients, 13 developed recurrences, including local progression within the radiation field in 3 and lymph node and/or distant metastases outside the radiation field in 10, at 3-43 months after treatment. The 2- and 5-year local progression-free rates were 91% and 84%, respectively. Of the 22 patients, 7 patients had died at 33-73 months after RT. The cause of death was tumor progression in 4, infectious pneumonia in 2, and renal failure in 1 patient. The overall and cause-specific survival rates were 100% for both at 2 years and 53% and 73% at 5 years, respectively. No therapy-related Grade 3 or greater toxicity was observed. Conclusions: RT is safe and effective for patients with EMPD. It appears to contribute to prolonged survival as a result of good tumor control.

  9. Adjuvant Radiotherapy for Gastric Cancer: A Dosimetric Comparison of 3-Dimensional Conformal Radiotherapy, Tomotherapy (registered) and Conventional Intensity Modulated Radiotherapy Treatment Plans

    SciTech Connect

    Dahele, Max; Skinner, Matthew; Schultz, Brenda; Cardoso, Marlene; Bell, Chris; Ung, Yee C.

    2010-07-01

    Some patients with gastric cancer benefit from post-operative chemo-radiotherapy, but adequately irradiating the planning target volume (PTV) whilst avoiding organs at risk (OAR) can be difficult. We evaluate 3-dimensional conformal radiotherapy (CRT), conventional intensity-modulated radiotherapy (IMRT) and helical tomotherapy (TT). TT, 2 and 5-field (F) CRT and IMRT treatment plans with the same PTV coverage were generated for 5 patients and compared. Median values are reported. The volume of left/right kidney receiving at least 20Gy (V20) was 57/51% and 51/60% for 2 and 5F-CRT, and 28/14% for TT and 27/19% for IMRT. The volume of liver receiving at least 30Gy (V30) was 45% and 62% for 2 and 5F-CRT, and 37% for TT and 35% for IMRT. With TT, 98% of the PTV received 95-105% of the prescribed dose, compared with 45%, 34% and 28% for 2F-CRT, 5F-CRT and IMRT respectively. Using conventional metrics, conventional IMRT can achieve comparable PTV coverage and OAR sparing to TT, but at the expense of PTV dose heterogeneity. Both irradiate large volumes of normal tissue to low doses. Additional studies are needed to demonstrate the clinical impact of these technologies.

  10. The primary treatment of advanced vocal cord cancer: laryngectomy or radiotherapy

    SciTech Connect

    van den Bogaert, W.; Ostyn, F.; van der Schueren, E.

    1983-03-01

    When different treatment modalities yield equal results in cancer treatment, the least mutilating is preferred. If results are different, however, the survival rate after treatment must be weighed against the quality of life. Considerable controversy exists concerning the primary treatment modality for advanced glottic cancer, with some authors defending surgery (with or without radiotherapy) and others defending radiotherapy as sole treatment, with laryngectomy reserved for local failures. From a group of 102 patients with T3 and T4 tumors, 65 were treated with a laryngectomy. Uncorrected survival at 5 years was 48%, local control was 75%. A group of 35 patients were treated with radiotherapy. Survival was 22% at 5 years, local control 23%, with rescue surgery 37%. These unfavorable results are related to the negative selection of patients for radiotherapy (inoperable, bad cooperation). In 14 patients who were operable but refused laryngectomy the final local control was 53%, with voice preservation in 34%; survival, however, remained low (27% at 5 years). Primary surgery seems to provide better chances for ultimate survival than radiotherapy alone. At the moment, it is not yet clear if a proportion of patients can be selected for whom a more conservative attitude can be allowed, with laryngectomy reserved for poor regression or recurrences after radiotherapy.

  11. Conformal Radiotherapy in the Treatment of Advanced Juvenile Nasopharyngeal Angiofibroma With Intracranial Extension: An Institutional Experience

    SciTech Connect

    Chakraborty, Santam; Ghoshal, Sushmita; Patil, Vijay Maruti; Oinam, Arun Singh; Sharma, Suresh C.

    2011-08-01

    Purpose: To describe the results of conformal radiotherapy in advanced juvenile nasopharyngeal angiofibroma in a tertiary care institution. Methods and Materials: Retrospective chart review was conducted for 8 patients treated with conformal radiotherapy between 2006 and 2009. The median follow-up was 17 months. All patients had Stage IIIB disease with intracranial extension. Radiotherapy was considered as treatment because patients were deemed inoperable owing to extensive intracranial/intraorbital extension or proximity to optic nerve. All but 1 patient were treated with intensity-modulated radiotherapy using seven coplanar fields. Median (range) dose prescribed was 39.6 (30-46) Gy. Actuarial analysis of local control and descriptive analysis of toxicity profile was conducted. Results: Despite the large and complex target volume (median planning target volume, 292 cm{sup 3}), intensity-modulated radiotherapy achieved conformal dose distributions (median van't Reit index, 0.66). Significant sparing of the surrounding organs at risk was obtained. No significant Grade 3/4 toxicities were experienced during or after treatment. Actual local control at 2 years was 87.5%. One patient died 1 month after radiotherapy secondary to massive epistaxis. The remaining 7 patients had progressive resolution of disease and were symptom-free at last follow-up. Persistent rhinitis was the only significant toxicity, seen in 1 patient. Conclusions: Conformal radiotherapy results in good local control with minimal acute and late side effects in juvenile nasopharyngeal angiofibromas, even in the presence of advanced disease.

  12. A client–server framework for 3D remote visualization of radiotherapy treatment space

    PubMed Central

    Santhanam, Anand P.; Min, Yugang; Dou, Tai H.; Kupelian, Patrick; Low, Daniel A.

    2013-01-01

    Radiotherapy is safely employed for treating wide variety of cancers. The radiotherapy workflow includes a precise positioning of the patient in the intended treatment position. While trained radiation therapists conduct patient positioning, consultation is occasionally required from other experts, including the radiation oncologist, dosimetrist, or medical physicist. In many circumstances, including rural clinics and developing countries, this expertise is not immediately available, so the patient positioning concerns of the treating therapists may not get addressed. In this paper, we present a framework to enable remotely located experts to virtually collaborate and be present inside the 3D treatment room when necessary. A multi-3D camera framework was used for acquiring the 3D treatment space. A client–server framework enabled the acquired 3D treatment room to be visualized in real-time. The computational tasks that would normally occur on the client side were offloaded to the server side to enable hardware flexibility on the client side. On the server side, a client specific real-time stereo rendering of the 3D treatment room was employed using a scalable multi graphics processing units (GPU) system. The rendered 3D images were then encoded using a GPU-based H.264 encoding for streaming. Results showed that for a stereo image size of 1280 × 960 pixels, experts with high-speed gigabit Ethernet connectivity were able to visualize the treatment space at approximately 81 frames per second. For experts remotely located and using a 100 Mbps network, the treatment space visualization occurred at 8–40 frames per second depending upon the network bandwidth. This work demonstrated the feasibility of remote real-time stereoscopic patient setup visualization, enabling expansion of high quality radiation therapy into challenging environments. PMID:23440605

  13. Exogenous insulin treatment after hypofractionated radiotherapy in cats with diabetes mellitus and acromegaly.

    PubMed

    Dunning, M D; Lowrie, C S; Bexfield, N H; Dobson, J M; Herrtage, M E

    2009-01-01

    The optimal treatment for feline acromegaly has yet to be established. Surgical and medical therapies are minimally effective although radiotherapy might have greater efficacy. The purpose of this study was to review the response and outcome of cats with acromegaly and insulin-resistant diabetes mellitus (DM) to radiotherapy. That radiotherapy improves glycemic control in cats with acromegaly and that improved glycemic control is due to remission of clinical acromegaly; demonstrated by a fall in serum insulin-like growth factor-1 (IGF-1) concentrations. Fourteen cats with naturally occurring acromegaly. Retrospective case review; records of all cats treated for acromegaly with radiotherapy were reviewed from 1997 to 2008. Cats were selected on the basis of compatible clinical signs, laboratory features, and diagnostic imaging findings. Fourteen cats received radiotherapy, delivered in 10 fractions, 3 times a week to a total dose of 3,700 cGy. Thirteen of 14 cats had improved diabetic control after radiotherapy. These improvements were sustained for up to 60 months. DM progressed in 2 cats and 1 did not respond. Seven cats responded before the final treatment. Ten cats were euthanized, 1 as a consequence of radiotherapy. In 8 cats in which IGF-1 was measured after treatment, changes in its concentration did not reflect the clinical improvement in glycemic control. Radiotherapy represents an effective treatment for cats with insulin-resistant DM resulting from acromegaly. IGF-1 concentration after treatment does not provide a suitable method by which remission from either acromegaly or insulin-resistant DM may be assessed.

  14. Movie making as a cognitive distraction for paediatric patients receiving radiotherapy treatment: qualitative interview study

    PubMed Central

    Shrimpton, Bradley J M; Willis, David J; Tongs, Cáthal D; Rolfo, Aldo G

    2013-01-01

    Objectives To establish the outcomes achieved by using an innovative movie-making programme designed to reduce fear of radiotherapy among paediatric patients. Design Qualitative descriptive evaluation based on semistructured, qualitative interviews with purposeful sampling and thematic analysis. Setting Tertiary Cancer Centre. Participants 20 parents of paediatric patients who had produced a movie of their radiation therapy experience and were in a follow-up phase of cancer management. Results Participants attributed a broad range of outcomes to the movie-making program. These included that the programme had helped reduce anxiety and distress exhibited by paediatric patients and contributed to a willingness to receive treatment. Other outcomes were that the completed movies had been used in school reintegration and for maintaining social connections. Conclusions Allowing children to create a video of their experience of radiotherapy provided a range of benefits to paediatric patients that varied according to their needs. For some patients, movie-making offered a valuable medium for overcoming fear of the unknown as well as increasing understanding of treatment processes. For others, the development of a personalised video offered an important cognitive/attentional distraction through engaging with an age-appropriate activity. Together these outcomes helped children maintain self-control and a positive outlook. PMID:23328308

  15. Short treatment time and excellent treatment outcome in accelerated hyperfractionated radiotherapy for T1 glottic cancer.

    PubMed

    Tamaki, Yukihisa; Hieda, Yoko; Yoshida, Rika; Yoshizako, Takeshi; Fuchiwaki, Takafumi; Aoi, Noriaki; Sekihara, Kazumasa; Kitajima, Kazuhiro; Kawauchi, Hideyuki; Kitagaki, Hajime; Sasaki, Ryohei; Inomata, Taisuke

    2015-11-01

    Accelerated hyperfractionated radiotherapy was performed as treatment for patients with T1 glottic cancer, and its utility was evaluated based on treatment outcomes and adverse effects. Fifty-eight men who had undergone radiotherapy were retrospectively reviewed. Tumor classification was Tis in 4 patients, T1a in 38, and T1b in 16. Histological examination revealed squamous cell carcinoma in 55 patients. Travel time from home to hospital was 0-1 hour for 24 patients, 1-2 hours for 9, and >2 hours for 25. Laser vaporization was performed prior to radiotherapy in 38 patients, and 19 patients received concurrent chemotherapy with an agent such as S-1. Patients were irradiated twice daily using an irradiation container. Most patients received a dose of 1.5 Gy/fraction up to a total of 60 Gy. The median overall treatment time was 30 days, with a median observation period of 59.6 months. A complete response was observed in all patients. The 5-year overall survival, disease-free survival, and local control rates were 97.2%, 93.2%, and 97.8%, respectively. Although grade 3 pharyngeal mucositis was observed in 2 patients, there were no other grade 3 or higher acute adverse events. As late toxicity, grade 2 laryngeal edema and grade 1 laryngeal hemorrhage were observed in 1 patient each, but no serious events such as laryngeal necrosis or laryngeal stenosis were observed. In conclusion, this treatment method brings excellent outcome and will substantially reduce the treatment duration among patients who need to stay at nearby hotels while undergoing treatment at hospitals in rural areas.

  16. Stereotactic Body Radiotherapy for Treatment of Adrenal Metastases

    SciTech Connect

    Chawla, Sheema; Chen, Yuhchyau; Katz, Alan W.; Muhs, Ann G.; Philip, Abraham; Okunieff, Paul; Milano, Michael T.

    2009-09-01

    Purpose: To investigate the dosimetry and outcomes of patients undergoing stereotactic body radiotherapy (SBRT) for metastases to the adrenal glands. Methods and Materials: At University of Rochester, patients have been undergoing SBRT for limited metastases since 2001. We retrospectively reviewed 30 patients who had undergone SBRT for adrenal metastases from various primary sites, including lung (n = 20), liver (n = 3), breast (n = 3), melanoma (n = 1), pancreas (n = 1), head and neck (n = 1), and unknown primary (n = 1). Results: Of the 30 patients, 14 with five or fewer metastatic lesions (including adrenal) underwent SBRT, with the intent of controlling all known sites of metastatic disease, and 16 underwent SBRT for palliation or prophylactic palliation of bulky adrenal metastases. The prescribed dose ranged from 16 Gy in 4 fractions to 50 Gy in 10 fractions. The median dose was 40 Gy. Of the 30 patients, 24 had >3 months of follow-up with serial computed tomography. Of these 24 patients, 1 achieved a complete response, 15 achieved a partial response, 4 had stable disease, and 4 developed progressive disease. No patient developed symptomatic progression of their adrenal metastases. The 1-year survival, local control, and distant control rate was 44%, 55%, and 13%, respectively. No patient developed Radiation Therapy Oncology Group Grade 2 or greater toxicity. Conclusion: SBRT for adrenal metastases is well tolerated. Most patients developed widespread metastases shortly after treatment. Local control was poor, although this was a patient population selected for adverse risk factors, such as bulky disease. Additional studies are needed to determine the efficacy of SBRT for oligometastatic adrenal metastases, given the propensity of these patients to develop further disease progression.

  17. Could Radiotherapy Effectiveness Be Enhanced by Electromagnetic Field Treatment?

    PubMed Central

    Francisco, Artacho-Cordón; del Mar, Salinas-Asensio María; Irene, Calvente; Sandra, Ríos-Arrabal; Josefa, León; Elisa, Román-Marinetto; Nicolás, Olea; Isabel, Núñez María

    2013-01-01

    One of the main goals in radiobiology research is to enhance radiotherapy effectiveness without provoking any increase in toxicity. In this context, it has been proposed that electromagnetic fields (EMFs), known to be modulators of proliferation rate, enhancers of apoptosis and inductors of genotoxicity, might control tumor recruitment and, thus, provide therapeutic benefits. Scientific evidence shows that the effects of ionizing radiation on cellular compartments and functions are strengthened by EMF. Although little is known about the potential role of EMFs in radiotherapy (RT), the radiosensitizing effect of EMFs described in the literature could support their use to improve radiation effectiveness. Thus, we hypothesized that EMF exposure might enhance the ionizing radiation effect on tumor cells, improving the effects of RT. The aim of this paper is to review reports of the effects of EMFs in biological systems and their potential therapeutic benefits in radiotherapy. PMID:23867611

  18. Unilateral Radiotherapy for the Treatment of Tonsil Cancer

    SciTech Connect

    Chronowski, Gregory M.; Garden, Adam S.; Morrison, William H.; Frank, Steven J.; Schwartz, David L.; Shah, Shalin J.; Beadle, Beth M.; Gunn, G. Brandon; Kupferman, Michael E.; Ang, Kian K.; Rosenthal, David I.

    2012-05-01

    Purpose: To assess, through a retrospective review, clinical outcomes of patients with squamous cell carcinoma of the tonsil treated at the M. D. Anderson Cancer Center with unilateral radiotherapy techniques that irradiate the involved tonsil region and ipsilateral neck only. Methods and Materials: Of 901 patients with newly diagnosed squamous cell carcinoma of the tonsil treated with radiotherapy at our institution, we identified 102 that were treated using unilateral radiotherapy techniques. All patients had their primary site of disease restricted to the tonsillar fossa or anterior pillar, with <1 cm involvement of the soft palate. Patients had TX (n = 17 patients), T1 (n = 52), or T2 (n = 33) disease, with Nx (n = 3), N0 (n = 33), N1 (n = 23), N2a (n = 21), or N2b (n = 22) neck disease. Results: Sixty-one patients (60%) underwent diagnostic tonsillectomy before radiotherapy. Twenty-seven patients (26%) underwent excision of a cervical lymph node or neck dissection before radiotherapy. Median follow-up for surviving patients was 38 months. Locoregional control at the primary site and ipsilateral neck was 100%. Two patients experienced contralateral nodal recurrence (2%). The 5-year overall survival and disease-free survival rates were 95% and 96%, respectively. The 5-year freedom from contralateral nodal recurrence rate was 96%. Nine patients required feeding tubes during therapy. Of the 2 patients with contralateral recurrence, 1 experienced an isolated neck recurrence and was salvaged with contralateral neck dissection only and remains alive and free of disease. The other patient presented with a contralateral base of tongue tumor and involved cervical lymph node, which may have represented a second primary tumor, and died of disease. Conclusions: Unilateral radiotherapy for patients with TX-T2, N0-N2b primary tonsil carcinoma results in high rates of disease control, with low rates of contralateral nodal failure and a low incidence of acute toxicity

  19. Radiotherapy treatment planning based on Monte Carlo techniques

    NASA Astrophysics Data System (ADS)

    Juste, Belén; Miró, Rafael; Campayo, Juan M.; Díez, Sergio; Verdú, Gumersindo

    2010-07-01

    At the present, treatment planning systems (TPS) used in radiotherapy treatments use determinist correlations based on measurements in water to evaluate doses in the volume of interest and dose distributions around it. Nevertheless, it is well known that doses assigned with this type of planner can be problematic, especially in the presence of heterogeneities. The present work has developed a computational model using the Monte Carlo (MC) code MCNP5 (Monte Carlo N-Particle) for the simulation of a 6 MeV photon beam emitted by Elekta Precise medical linear accelerator treatment head. The model includes the major components of the accelerator head and the cube-shaped heterogeneous water tank " RFA-300". A low-density heterogeneity has been placed inside this water tank. It consists of a extruded polystyrene piece (97% air and 3% polystyrene) whose dimensions are 30 cm×10 cm×8 cm and with a density of 0.0311 g/cm 3. Calculations were performed for a photon beam setting 10 cm×10 cm and 20 cm×20 cm irradiation field sizes at 100 cm distance from source. The MC simulation is able to predict the absorbed dose distribution within the water tank using the *F8 or FMESH4 tally. These results have been compared with experimental values measured at the Hospital Clínic Universitari de Valencia. Dosimetric parameters calculated by simulation at the water tank and the experimental measures agreed, with an average deviation inside the heterogeneity region of 3%. Simulation results have been also compared with dose curves predicted by a commercial TPS in the same irradiation conditions, focusing attention on the accuracy that both systems reach in the dose calculation at the interphase zone and inside the heterogeneity. In contrast, TPS results overestimate the dose inside the heterogeneity and after it, with a maximum deviation of 7% for the 6 MeV photon beam and a field size of 20 cm×20 cm. We can conclude that the algorithms of computation of the TPS are not able to predict

  20. Quality assurance of radiotherapy in cancer treatment: toward improvement of patient safety and quality of care.

    PubMed

    Ishikura, Satoshi

    2008-11-01

    The process of radiotherapy (RT) is complex and involves understanding of the principles of medical physics, radiobiology, radiation safety, dosimetry, radiation treatment planning, simulation and interaction of radiation with other treatment modalities. Each step in the integrated process of RT needs quality control and quality assurance (QA) to prevent errors and to give high confidence that patients will receive the prescribed treatment correctly. Recent advances in RT, including intensity-modulated and image-guided RT, focus on the need for a systematic RTQA program that balances patient safety and quality with available resources. It is necessary to develop more formal error mitigation and process analysis methods, such as failure mode and effect analysis, to focus available QA resources optimally on process components. External audit programs are also effective. The International Atomic Energy Agency has operated both an on-site and off-site postal dosimetry audit to improve practice and to assure the dose from RT equipment. Several countries have adopted a similar approach for national clinical auditing. In addition, clinical trial QA has a significant role in enhancing the quality of care. The Advanced Technology Consortium has pioneered the development of an infrastructure and QA method for advanced technology clinical trials, including credentialing and individual case review. These activities have an impact not only on the treatment received by patients enrolled in clinical trials, but also on the quality of treatment administered to all patients treated in each institution, and have been adopted globally; by the USA, Europe and Japan also.

  1. Severe cutaneous toxicity following treatment with radiotherapy and cetuximab: a case report.

    PubMed

    Azad, Arun

    2009-01-07

    While the addition of cetuximab to radiotherapy improves clinical outcomes in locoregionally advanced head and neck squamous cell cancers, there are a small number of reports of severe radiation dermatitis occurring with this therapeutic combination. We present the case of a 69 year old male who developed severe radiation dermatitis following treatment with cetuximab and radiotherapy for a locoregionally advanced head and neck squamous cell cancer.

  2. Resistance of Nonmelanoma Skin Cancer to Nonsurgical Treatments. Part II: Photodynamic Therapy, Vismodegib, Cetuximab, Intralesional Methotrexate, and Radiotherapy.

    PubMed

    Gracia-Cazaña, T; Salazar, N; Zamarrón, A; Mascaraque, M; Lucena, S R; Juarranz, Á

    2016-11-01

    A wide range of treatments is now available for nonmelanoma skin cancer, including 5-fluorouracil, ingenol mebutate, imiquimod, diclofenac, photodynamic therapy, methotrexate, cetuximab, vismodegib, and radiotherapy. All are associated with high clinical and histologic response rates. However, some tumors do not respond due to resistance, which may be primary or acquired. Study of the resistance processes is a broad area of research that aims to increase our understanding of the nature of each tumor and the biologic features that make it resistant, as well as to facilitate the design of new therapies directed against these tumors. In this second article, having covered the topical treatments of nonmelanoma skin cancer, we review resistance to other nonsurgical treatments, such as monoclonal antibodies against basal and squamous cell carcinomas, intralesional chemotherapy, photodynamic therapy, and radiotherapy.

  3. A semiautomatic tool for prostate segmentation in radiotherapy treatment planning

    PubMed Central

    2014-01-01

    Background Delineation of the target volume is a time-consuming task in radiotherapy treatment planning, yet essential for a successful treatment of cancers such as prostate cancer. To facilitate the delineation procedure, the paper proposes an intuitive approach for 3D modeling of the prostate by slice-wise best fitting ellipses. Methods The proposed estimate is initialized by the definition of a few control points in a new patient. The method is not restricted to particular image modalities but assumes a smooth shape with elliptic cross sections of the object. A training data set of 23 patients was used to calculate a prior shape model. The mean shape model was evaluated based on the manual contour of 10 test patients. The patient records of training and test data are based on axial T1-weighted 3D fast-field echo (FFE) sequences. The manual contours were considered as the reference model. Volume overlap (Vo), accuracy (Ac) (both ratio, range 0-1, optimal value 1) and Hausdorff distance (HD) (mm, optimal value 0) were calculated as evaluation parameters. Results The median and median absolute deviation (MAD) between manual delineation and deformed mean best fitting ellipses (MBFE) was Vo (0.9 ± 0.02), Ac (0.81 ± 0.03) and HD (4.05 ± 1.3)mm and between manual delineation and best fitting ellipses (BFE) was Vo (0.96 ± 0.01), Ac (0.92 ± 0.01) and HD (1.6 ± 0.27)mm. Additional results show a moderate improvement of the MBFE results after Monte Carlo Markov Chain (MCMC) method. Conclusions The results emphasize the potential of the proposed method of modeling the prostate by best fitting ellipses. It shows the robustness and reproducibility of the model. A small sample test on 8 patients suggest possible time saving using the model. PMID:24460666

  4. Dosimetric verification of radiotherapy treatment planning systems in Serbia: national audit.

    PubMed

    Rutonjski, Laza; Petrović, Borislava; Baucal, Milutin; Teodorović, Milan; Cudić, Ozren; Gershkevitsh, Eduard; Izewska, Joanna

    2012-09-12

    Independent external audits play an important role in quality assurance programme in radiation oncology. The audit supported by the IAEA in Serbia was designed to review the whole chain of activities in 3D conformal radiotherapy (3D-CRT) workflow, from patient data acquisition to treatment planning and dose delivery. The audit was based on the IAEA recommendations and focused on dosimetry part of the treatment planning and delivery processes. The audit was conducted in three radiotherapy departments of Serbia. An anthropomorphic phantom was scanned with a computed tomography unit (CT) and treatment plans for eight different test cases involving various beam configurations suggested by the IAEA were prepared on local treatment planning systems (TPSs). The phantom was irradiated following the treatment plans for these test cases and doses in specific points were measured with an ionization chamber. The differences between the measured and calculated doses were reported. The measurements were conducted for different photon beam energies and TPS calculation algorithms. The deviation between the measured and calculated values for all test cases made with advanced algorithms were within the agreement criteria, while the larger deviations were observed for simpler algorithms. The number of measurements with results outside the agreement criteria increased with the increase of the beam energy and decreased with TPS calculation algorithm sophistication. Also, a few errors in the basic dosimetry data in TPS were detected and corrected. The audit helped the users to better understand the operational features and limitations of their TPSs and resulted in increased confidence in dose calculation accuracy using TPSs. The audit results indicated the shortcomings of simpler algorithms for the test cases performed and, therefore the transition to more advanced algorithms is highly desirable.

  5. Physicochemical treatment processes

    SciTech Connect

    Grasso, D.; Morico, K.; Kock, N.; Flood, K.; Armstrong, R. ); Walters, R. ); Ellis, G. ); Chin, Yuping )

    1990-06-01

    This article discussed work done and accomplishments made in various methods and processes for physicochemical wastewater treatment. Processes discussed include general, precipitation, coagulation/flocculation, sedimentation/flotation, filtration, adsorption, ion exchange, membrane processes, mass transfer processes, phtotlytic processes, and oxidation/reduction processes.

  6. Oesophagus side effects related to the treatment of oesophageal cancer or radiotherapy of other thoracic malignancies.

    PubMed

    Adebahr, Sonja; Schimek-Jasch, Tanja; Nestle, Ursula; Brunner, Thomas B

    2016-08-01

    The oesophagus as a serial organ located in the central chest is frequent subject to "incidental" dose application in radiotherapy for several thoracic malignancies including oesophageal cancer itself. Especially due to the radiosensitive mucosa severe radiotherapy induced sequelae can occur, acute oesophagitis and strictures as late toxicity being the most frequent side-effects. In this review we focus on oesophageal side effects derived from treatment of gastrointestinal cancer and secondly provide an overview on oesophageal toxicity from conventional and stereotactic fractionated radiotherapy to the thoracic area in general. Available data on pathogenesis, frequency, onset, and severity of oesophageal side effects are summarized. Whereas for conventional radiotherapy the associations of applied doses to certain volumes of the oesophagus are well described, the tolerance dose to the mediastinal structures for hypofractionated therapy is unknown. The review provides available attempts to predict the risk of oesophageal side effects from dosimetric parameters of SBRT.

  7. Radiotherapy dose enhancement using BNCT in conventional LINACs high-energy treatment: Simulation and experiment

    PubMed Central

    Alikaniotis, Katia; Borla, Oscar; Monti, Valeria; Vivaldo, Gianna; Zanini, Alba; Giannini, Gianrossano

    2016-01-01

    Aim To employ the thermal neutron background that affects the patient during a traditional high-energy radiotherapy treatment for BNCT (Boron Neutron Capture Therapy) in order to enhance radiotherapy effectiveness. Background Conventional high-energy (15–25 MV) linear accelerators (LINACs) for radiotherapy produce fast secondary neutrons in the gantry with a mean energy of about 1 MeV due to (γ, n) reaction. This neutron flux, isotropically distributed, is considered as an unavoidable undesired dose during the treatment. Considering the moderating effect of human body, a thermal neutron fluence is localized in the tumour area: this neutron background could be employed for BNCT by previously administering 10B-Phenyl-Alanine (10BPA) to the patient. Materials and methods Monte Carlo simulations (MCNP4B-GN code) were performed to estimate the total amount of neutrons outside and inside human body during a traditional X-ray radiotherapy treatment. Moreover, a simplified tissue equivalent anthropomorphic phantom was used together with bubble detectors for thermal and fast neutron to evaluate the moderation effect of human body. Results Simulation and experimental results confirm the thermal neutron background during radiotherapy of 1.55E07 cm−2 Gy−1. The BNCT equivalent dose delivered at 4 cm depth in phantom is 1.5 mGy-eq/Gy, that is about 3 Gy-eq (4% of X-rays dose) for a 70 Gy IMRT treatment. Conclusions The thermal neutron component during a traditional high-energy radiotherapy treatment could produce a localized BNCT effect, with a localized therapeutic dose enhancement, corresponding to 4% or more of photon dose, following tumour characteristics. This BNCT additional dose could thus improve radiotherapy, acting as a localized radio-sensitizer. PMID:26933394

  8. Use of hyperthermia and radiotherapy in treatment of a large mast cell sarcoma in a dog.

    PubMed

    Legorreta, R A; Denman, D L; Kelley, M C; Lewis, G C

    1988-12-15

    A large infiltrating mast cell sarcoma in a dog, which had been refractory before surgical excision, was controlled 2 months after completion of a combined radiotherapy and hyperthermia regimen. Treatment resulted in rapid tumor necrosis and resultant ulceration of adjacent skin. Ulceration was transient, resolving concurrently with tumor control. Radiation was administered as 3.5-Gy fractions 3 times/week, resulting in a total dose of 45.5 Gy in 13 treatments. Hyperthermia (44 C for 30 minutes) was given 4 to 5 hours after radiotherapy, once a week during the first 3 weeks of treatment.

  9. A multicriteria framework with voxel-dependent parameters for radiotherapy treatment plan optimization

    SciTech Connect

    Zarepisheh, Masoud; Uribe-Sanchez, Andres F.; Li, Nan; Jia, Xun; Jiang, Steve B.

    2014-04-15

    Purpose: To establish a new mathematical framework for radiotherapy treatment optimization with voxel-dependent optimization parameters. Methods: In the treatment plan optimization problem for radiotherapy, a clinically acceptable plan is usually generated by an optimization process with weighting factors or reference doses adjusted for a set of the objective functions associated to the organs. Recent discoveries indicate that adjusting parameters associated with each voxel may lead to better plan quality. However, it is still unclear regarding the mathematical reasons behind it. Furthermore, questions about the objective function selection and parameter adjustment to assure Pareto optimality as well as the relationship between the optimal solutions obtained from the organ-based and voxel-based models remain unanswered. To answer these questions, the authors establish in this work a new mathematical framework equipped with two theorems. Results: The new framework clarifies the different consequences of adjusting organ-dependent and voxel-dependent parameters for the treatment plan optimization of radiation therapy, as well as the impact of using different objective functions on plan qualities and Pareto surfaces. The main discoveries are threefold: (1) While in the organ-based model the selection of the objective function has an impact on the quality of the optimized plans, this is no longer an issue for the voxel-based model since the Pareto surface is independent of the objective function selection and the entire Pareto surface could be generated as long as the objective function satisfies certain mathematical conditions; (2) All Pareto solutions generated by the organ-based model with different objective functions are parts of a unique Pareto surface generated by the voxel-based model with any appropriate objective function; (3) A much larger Pareto surface is explored by adjusting voxel-dependent parameters than by adjusting organ-dependent parameters, possibly

  10. Radiotherapy treatment of keloid scars with a kilovoltage X-ray parallel pair.

    PubMed

    Eaton, David J; Barber, Elizabeth; Ferguson, Leila; Mark Simpson, G; Collis, Christopher H

    2012-03-01

    An established treatment for keloids is surgery and radiotherapy, using a single applied field. However, earlobe keloids lend themselves to a parallel opposed pair approach. Delivery with a superficial X-ray unit is practicable and improves homogeneity within the treatment volume. It has been implemented in this centre since 2007.

  11. Optimization of Breast Cancer Treatment by Dynamic Intensity Modulated Electron Radiotherapy

    DTIC Science & Technology

    2006-04-01

    AD_________________ Award Number: DAMD17-01-1-0435 TITLE: Optimization of Breast Cancer Treatment by...Optimization of Breast Cancer Treatment by Dynamic Intensity Modulated Electron Radiotherapy 5b. GRANT NUMBER DAMD17-01-1-0435 5c. PROGRAM ELEMENT

  12. Application of failure mode and effects analysis to treatment planning in scanned proton beam radiotherapy

    PubMed Central

    2013-01-01

    Background A multidisciplinary and multi-institutional working group applied the Failure Mode and Effects Analysis (FMEA) approach to the actively scanned proton beam radiotherapy process implemented at CNAO (Centro Nazionale di Adroterapia Oncologica), aiming at preventing accidental exposures to the patient. Methods FMEA was applied to the treatment planning stage and consisted of three steps: i) identification of the involved sub-processes; ii) identification and ranking of the potential failure modes, together with their causes and effects, using the risk probability number (RPN) scoring system, iii) identification of additional safety measures to be proposed for process quality and safety improvement. RPN upper threshold for little concern of risk was set at 125. Results Thirty-four sub-processes were identified, twenty-two of them were judged to be potentially prone to one or more failure modes. A total of forty-four failure modes were recognized, 52% of them characterized by an RPN score equal to 80 or higher. The threshold of 125 for RPN was exceeded in five cases only. The most critical sub-process appeared related to the delineation and correction of artefacts in planning CT data. Failures associated to that sub-process were inaccurate delineation of the artefacts and incorrect proton stopping power assignment to body regions. Other significant failure modes consisted of an outdated representation of the patient anatomy, an improper selection of beam direction and of the physical beam model or dose calculation grid. The main effects of these failures were represented by wrong dose distribution (i.e. deviating from the planned one) delivered to the patient. Additional strategies for risk mitigation, easily and immediately applicable, consisted of a systematic information collection about any known implanted prosthesis directly from each patient and enforcing a short interval time between CT scan and treatment start. Moreover, (i) the investigation of

  13. Helium ions for radiotherapy? Physical and biological verifications of a novel treatment modality.

    PubMed

    Krämer, Michael; Scifoni, Emanuele; Schuy, Christoph; Rovituso, Marta; Tinganelli, Walter; Maier, Andreas; Kaderka, Robert; Kraft-Weyrather, Wilma; Brons, Stephan; Tessonnier, Thomas; Parodi, Katia; Durante, Marco

    2016-04-01

    Modern facilities for actively scanned ion beam radiotherapy allow in principle the use of helium beams, which could present specific advantages, especially for pediatric tumors. In order to assess the potential use of these beams for radiotherapy, i.e., to create realistic treatment plans, the authors set up a dedicated (4)He beam model, providing base data for their treatment planning system TRiP98, and they have reported that in this work together with its physical and biological validations. A semiempirical beam model for the physical depth dose deposition and the production of nuclear fragments was developed and introduced in TRiP98. For the biological effect calculations the last version of the local effect model was used. The model predictions were experimentally verified at the HIT facility. The primary beam attenuation and the characteristics of secondary charged particles at various depth in water were investigated using (4)He ion beams of 200 MeV/u. The nuclear charge of secondary fragments was identified using a ΔE/E telescope. 3D absorbed dose distributions were measured with pin point ionization chambers and the biological dosimetry experiments were realized irradiating a Chinese hamster ovary cells stack arranged in an extended target. The few experimental data available on basic physical processes are reproduced by their beam model. The experimental verification of absorbed dose distributions in extended target volumes yields an overall agreement, with a slight underestimation of the lateral spread. Cell survival along a 4 cm extended target is reproduced with remarkable accuracy. The authors presented a simple simulation model for therapeutical (4)He beams which they introduced in TRiP98, and which is validated experimentally by means of physical and biological dosimetries. Thus, it is now possible to perform detailed treatment planning studies with (4)He beams, either exclusively or in combination with other ion modalities.

  14. Feasibility Study of Intensity-Modulated Radiotherapy (IMRT) Treatment Planning Using Brain Functional MRI

    SciTech Connect

    Chang Jenghwa Kowalski, Alex; Hou, Bob; Narayana, Ashwatha

    2008-04-01

    The purpose of this work was to study the feasibility of incorporating functional magnetic resonance imaging (fMRI) information for intensity modulated radiotherapy (IMRT) treatment planning of brain tumors. Three glioma patients were retrospectively replanned for radiotherapy (RT) with additional fMRI information. The fMRI of each patient was acquired using a bilateral finger-tapping paradigm with a gradient echo EPI (Echo Planer Imaging) sequence. The fMRI data were processed using the Analysis of Functional Neuroimaging (AFNI) software package for determining activation volumes, and the volumes were fused with the simulation computed tomography (CT) scan. The actived pixels in left and right primary motor cortexes (PMCs) were contoured as critical structures for IMRT planning. The goal of replanning was to minimize the RT dose to the activation volumes in the PMC regions, while maintaining a similar coverage to the planning target volume (PTV) and keeping critical structures within accepted dose tolerance. Dose-volume histograms of the treatment plans with and without considering the fMRI information were compared. Beam angles adjustment or additional beams were needed for 2 cases to meet the planning criteria. Mean dose to the contralateral and ipsilateral PMC was significantly reduced by 66% and 55%, respectively, for 1 patient. For the other 2 patients, mean dose to contralateral PMC region was lowered by 73% and 69%. In general, IMRT optimization can reduce the RT dose to the PMC regions without compromising the PTV coverage or sparing of other critical organs. In conclusion, it is feasible to incorporate the fMRI information into the RT treatment planning. IMRT planning allows a significant reduction in RT dose to the PMC regions, especially if the region does not lie within the PTV.

  15. Helium ions for radiotherapy? Physical and biological verifications of a novel treatment modality

    SciTech Connect

    Krämer, Michael Scifoni, Emanuele; Schuy, Christoph; Rovituso, Marta; Maier, Andreas; Kaderka, Robert; Kraft-Weyrather, Wilma; Tinganelli, Walter; Durante, Marco; Brons, Stephan; Tessonnier, Thomas; Parodi, Katia

    2016-04-15

    Purpose: Modern facilities for actively scanned ion beam radiotherapy allow in principle the use of helium beams, which could present specific advantages, especially for pediatric tumors. In order to assess the potential use of these beams for radiotherapy, i.e., to create realistic treatment plans, the authors set up a dedicated {sup 4}He beam model, providing base data for their treatment planning system TRiP98, and they have reported that in this work together with its physical and biological validations. Methods: A semiempirical beam model for the physical depth dose deposition and the production of nuclear fragments was developed and introduced in TRiP98. For the biological effect calculations the last version of the local effect model was used. The model predictions were experimentally verified at the HIT facility. The primary beam attenuation and the characteristics of secondary charged particles at various depth in water were investigated using {sup 4}He ion beams of 200 MeV/u. The nuclear charge of secondary fragments was identified using a ΔE/E telescope. 3D absorbed dose distributions were measured with pin point ionization chambers and the biological dosimetry experiments were realized irradiating a Chinese hamster ovary cells stack arranged in an extended target. Results: The few experimental data available on basic physical processes are reproduced by their beam model. The experimental verification of absorbed dose distributions in extended target volumes yields an overall agreement, with a slight underestimation of the lateral spread. Cell survival along a 4 cm extended target is reproduced with remarkable accuracy. Conclusions: The authors presented a simple simulation model for therapeutical {sup 4}He beams which they introduced in TRiP98, and which is validated experimentally by means of physical and biological dosimetries. Thus, it is now possible to perform detailed treatment planning studies with {sup 4}He beams, either exclusively or in

  16. Early versus delayed postoperative radiotherapy for treatment of low-grade gliomas

    PubMed Central

    Sarmiento, J Manuel; Venteicher, Andrew S; Patil, Chirag G

    2015-01-01

    Background In most people with low-grade gliomas (LGG), the primary treatment regimen remains a combination of surgery followed by postoperative radiotherapy. However, the optimal timing of radiotherapy is controversial. It is unclear whether to use radiotherapy in the early postoperative period, or whether radiotherapy should be delayed until tumour progression occurs. Objectives To assess the effects of early postoperative radiotherapy versus radiotherapy delayed until tumour progression for low-grade intracranial gliomas in people who had initial biopsy or surgical resection. Search methods We searched up to September 2014 the following electronic databases: the Cochrane Register of Controlled Trials (CENTRAL, Issue 8, 2014), MEDLINE (1948 to Aug week 3, 2014), and EMBASE (1980 to Aug week 3, 2014) to identify trials for inclusion in this Cochrane review. Selection criteria We included randomised controlled trials (RCTs) that compared early versus delayed radiotherapy following biopsy or surgical resection for the treatment of people with newly diagnosed intracranial LGG (astrocytoma, oligodendroglioma, mixed oligoastrocytoma, astroblastoma, xanthoastrocytoma, or ganglioglioma). Radiotherapy may include conformal external beam radiotherapy (EBRT) with linear accelerator or cobalt-60 sources, intensity-modulated radiotherapy (IMRT), or stereotactic radiosurgery (SRS). Data collection and analysis Three review authors independently assessed the trials for inclusion and risk of bias, and extracted study data. We resolved any differences between review authors by discussion. Adverse effects were also extracted from the study report. We performed meta-analyses using a random-effects model with inverse variance weighting. Main results We included one large, multi-institutional, prospective RCT, involving 311 participants; the risk of bias in this study was unclear. This study found that early postoperative radiotherapy is associated with an increase in time to

  17. Review of ultrasound image guidance in external beam radiotherapy: I. Treatment planning and inter-fraction motion management

    NASA Astrophysics Data System (ADS)

    Fontanarosa, Davide; van der Meer, Skadi; Bamber, Jeffrey; Harris, Emma; O'Shea, Tuathan; Verhaegen, Frank

    2015-02-01

    In modern radiotherapy, verification of the treatment to ensure the target receives the prescribed dose and normal tissues are optimally spared has become essential. Several forms of image guidance are available for this purpose. The most commonly used forms of image guidance are based on kilovolt or megavolt x-ray imaging. Image guidance can also be performed with non-harmful ultrasound (US) waves. This increasingly used technique has the potential to offer both anatomical and functional information. This review presents an overview of the historical and current use of two-dimensional and three-dimensional US imaging for treatment verification in radiotherapy. The US technology and the implementation in the radiotherapy workflow are described. The use of US guidance in the treatment planning process is discussed. The role of US technology in inter-fraction motion monitoring and management is explained, and clinical studies of applications in areas such as the pelvis, abdomen and breast are reviewed. A companion review paper (O’Shea et al 2015 Phys. Med. Biol. submitted) will extensively discuss the use of US imaging for intra-fraction motion quantification and novel applications of US technology to RT.

  18. LINAC radiosurgery and radiotherapy treatment of acoustic neuromas. 2007.

    PubMed

    Likhterov, Ilya; Allbright, Robert M; Selesnick, Samuel H

    2008-04-01

    This article provides an introduction to radiation therapy as it applies to intracranial tumors. It also provides a review of the natural growth progression of acoustic neuromas and accuracy of tumor size determination. Literature on the use of linear accelerator stereotactic radiosurgery and fractionated radiotherapy in acoustic neuroma management is reviewed and summarized. Specifically, the rates of reported tumor control, hearing preservation, facial and trigeminal nerve complications, and hydrocephalus are analyzed. Although the complication rates associated with linear accelerator therapy are relatively low, hearing preservation is poor and acoustic neuroma control is variable.

  19. LINAC radiosurgery and radiotherapy treatment of acoustic neuromas.

    PubMed

    Likhterov, Ilya; Allbright, Robert M; Selesnick, Samuel H

    2007-06-01

    This article provides an introduction to radiation therapy as it applies to intracranial tumors. It also provides a review of the natural growth progression of acoustic neuromas and accuracy of tumor size determination. Literature on the use of linear accelerator stereotactic radiosurgery and fractionated radiotherapy in acoustic neuroma management is reviewed and summarized. Specifically, the rates of reported tumor control, hearing preservation, facial and trigeminal nerve complications, and hydrocephalus are analyzed. Although the complication rates associated with linear accelerator therapy are relatively low, hearing preservation is poor and acoustic neuroma control is variable.

  20. Cone Beam Computed Tomography-Derived Adaptive Radiotherapy for Radical Treatment of Esophageal Cancer

    SciTech Connect

    Hawkins, Maria A.; Brooks, Corrinne; Hansen, Vibeke N.; Aitken, Alexandra; Tait, Diana M.

    2010-06-01

    Purpose: To investigate the potential for reduction in normal tissue irradiation by creating a patient specific planning target volume (PTV) using cone beam computed tomography (CBCT) imaging acquired in the first week of radiotherapy for patients receiving radical radiotherapy. Methods and materials: Patients receiving radical RT for carcinoma of the esophagus were investigated. The PTV is defined as CTV(tumor, nodes) plus esophagus outlined 3 to 5 cm cranio-caudally and a 1.5-cm circumferential margin is added (clinical plan). Prefraction CBCT are acquired on Days 1 to 4, then weekly. No correction for setup error made. The images are imported into the planning system. The tumor and esophagus for the length of the PTV are contoured on each CBCT and 5 mm margin is added. A composite volume (PTV1) is created using Week 1 composite CBCT volumes. The same process is repeated using CBCT Week 2 to 6 (PTV2). A new plan is created using PTV1 (adaptive plan). The coverage of the 95% isodose of PTV1 is evaluated on PTV2. Dose-volume histograms (DVH) for lungs, heart, and cord for two plans are compared. Results: A total of 139 CBCT for 14 cases were analyzed. For the adaptive plan the coverage of the 95% prescription isodose for PTV1 = 95.6% +- 4% and the PTV2 = 96.8% +- 4.1% (t test, 0.19). Lungs V20 (15.6 Gy vs. 10.2 Gy) and heart mean dose (26.9 Gy vs. 20.7 Gy) were significantly smaller for the adaptive plan. Conclusions: A reduced planning volume can be constructed within the first week of treatment using CBCT. A single plan modification can be performed within the second week of treatment with considerable reduction in organ at risk dose.

  1. Place of radiotherapy in the treatment of synovial sarcoma

    SciTech Connect

    Carson, J.H.; Harwood, A.R.; Cummings, B.J.; Fornasier, V.; Langer, F.; Quirt, I.

    1981-01-01

    This paper reviews 36 patients with synovial sarcoma; 18 were referred within three months of surgery. None had undergone en bloc excision and all were treated with post-operative radiotherapy. Local control and survival were analyzed with respect to Tumor Node Metastasis Classification, histology, site of primary and surgical procedure. Eight patients with T1-2N0M0 tumors were alive and well (minimum two year follow-up) following excision and radiotherapy; 7 had a normally functional extremity. In contrast, only one of 8 patients with T3N0M0 tumors is alive and well. Seven of 8 patients with well or moderately differentiated histology were alive and well whereas no patient with poorly differentiated histologies survived. Six of 7 patients were alive and well if their tumor was distal to the elbow or knee whereas none of those who had a primary thigh synovial sarcoma survived. Eighteen patients were referred with recurrent disease and 2 were salvaged. A management policy is proposed for synovial sarcoma with the integrated use of surgery, radiation and chemotherapy; it emphasizes optimal cure rates and a functional extremity reserving amputation for salvage.

  2. Routine EPID in-vivo dosimetry in a reference point for conformal radiotherapy treatments

    NASA Astrophysics Data System (ADS)

    Fidanzio, Andrea; Azario, Luigi; Greco, Francesca; Cilla, Savino; Piermattei, Angelo

    2015-04-01

    In-vivo dosimetry (IVD) in external beam radiotherapy is used to detect major clinically relevant differences between planned and delivered dose. Moreover, a detailed analysis of its results, when routinely reported and discussed by the radiotherapy staff, can limit the likelihood of error transmission to many treatments. A first experience of routine EPID-based IVD in a reference point has been performed in our department for 3D-CRT treatments over a three-year period. More than 14 000 images were acquired and 1287 treatment plans were verified. The IVD checks were obtained three times in the first week and then weekly. Tolerance levels of ±5% for pelvic-abdomen, head-neck and breast irradiations and ±6% for lung treatments were adopted for the in-vivo measured dose per fraction. A statistical analysis of the IVD results was performed grouping the data by: anatomical regions, treatment units, open and wedged fields and gantry angles. About 10% of the checked doses per fraction showed dosimetric discrepancies out of the tolerance levels. The causes of the discrepancies were 70% delivery or planning errors, 20% morphological changes and 10% procedural limitations. 41 cases (3.2%) have required special investigations because their in-vivo doses per fraction, averaged over the first three sessions, were out of the tolerance levels and in 19 cases (1.5%) the deviations gave rise to an intervention. Statistically significant differences of average variations between planned and delivered doses were observed for: (i) 30° wedged 10 MV fields with respect to those of other wedged or open 10 MV fields delivered by two linacs, due to the incorrect TPS implementation of that wedge transmission factor; (ii) anterior-posterior and posterior-anterior beams with respect to the other gantry orientations for one linac, due to the beam attenuation introduced by the treatment couch; (iii) lateral fields with respect to medial fields of breast irradiations for all linacs, due

  3. Routine EPID in-vivo dosimetry in a reference point for conformal radiotherapy treatments.

    PubMed

    Fidanzio, Andrea; Azario, Luigi; Greco, Francesca; Cilla, Savino; Piermattei, Angelo

    2015-04-21

    In-vivo dosimetry (IVD) in external beam radiotherapy is used to detect major clinically relevant differences between planned and delivered dose. Moreover, a detailed analysis of its results, when routinely reported and discussed by the radiotherapy staff, can limit the likelihood of error transmission to many treatments. A first experience of routine EPID-based IVD in a reference point has been performed in our department for 3D-CRT treatments over a three-year period. More than 14,000 images were acquired and 1287 treatment plans were verified. The IVD checks were obtained three times in the first week and then weekly. Tolerance levels of ± 5% for pelvic-abdomen, head-neck and breast irradiations and ± 6% for lung treatments were adopted for the in-vivo measured dose per fraction. A statistical analysis of the IVD results was performed grouping the data by: anatomical regions, treatment units, open and wedged fields and gantry angles. About 10% of the checked doses per fraction showed dosimetric discrepancies out of the tolerance levels. The causes of the discrepancies were 70% delivery or planning errors, 20% morphological changes and 10% procedural limitations. 41 cases (3.2%) have required special investigations because their in-vivo doses per fraction, averaged over the first three sessions, were out of the tolerance levels and in 19 cases (1.5%) the deviations gave rise to an intervention. Statistically significant differences of average variations between planned and delivered doses were observed for: (i) 30° wedged 10 MV fields with respect to those of other wedged or open 10 MV fields delivered by two linacs, due to the incorrect TPS implementation of that wedge transmission factor; (ii) anterior-posterior and posterior-anterior beams with respect to the other gantry orientations for one linac, due to the beam attenuation introduced by the treatment couch; (iii) lateral fields with respect to medial fields of breast irradiations for all linacs, due to

  4. Combined treatment with interstitial hyperthermia and interstitial radiotherapy in an animal tumor model.

    PubMed

    Ruifrok, A C; Levendag, P C; Lakeman, R F; Deurloo, I K; Visser, A G

    1991-06-01

    An interstitial hyperthermia system operating at 27 MHz has been developed at the Dr. Daniel den Hoed Cancer Center. To test this system in combination with interstitial radiotherapy and to study the interactions of interstitial radiotherapy and interstitial hyperthermia, animal experiments were performed using rhabdomyosarcoma type R1 transplanted in the flanks of female Wag/Rij rats. Using the 27 MHz system, it appeared feasible to obtain hyperthermic temperatures. In this experiment a thermal dose of 44 degrees C for 30 minutes was delivered by controlling the temperature at the periphery of the tumor to 44 degrees C. The interstitial heating applicators were inserted in four standard afterloading catheters implanted with a fixed spacing of 7 mm; the same catheters were used for the radioactive sources for interstitial radiotherapy treatment following the interstitial hyperthermia sessions. Interstitial radiotherapy was given by means of four Ir192 wires with an average activity of 4.5.10(7) Bq/cm. Minimum tumor doses of 20 to 115 Gy with a mean dose rate of 47 cGy/hour were applied. Interstitial hyperthermia alone resulted in a growth delay (GD1) of 6 +/- 2 days without significant reduction of tumor volume. The 50% tumor cure dose after interstitial radiotherapy alone was 95 +/- 9 Gy. Combination of interstitial hyperthermia and interstitial radiotherapy resulted in reduction of the 50% tumor cure dose to 48 +/- 13 Gy. The dose-effect data for cure for these modalities are compared to existing data for external irradiation and external hyperthermia in the same tumor model. It was found that the addition of hyperthermia to different modes of irradiation, that is, either to single dose or protracted radiotherapy, results in a common level of radiosensitivity through impaired repair of sublethal damage. This study demonstrates the feasibility of the 27 MHz heating system in achieving hyperthermic temperatures; in the combined modality experiments a thermal

  5. Nonrigid Image Registration for Head and Neck Cancer Radiotherapy Treatment Planning With PET/CT

    SciTech Connect

    Ireland, Rob H. . E-mail: r.ireland@sheffield.ac.uk; Dyker, Karen E.; Barber, David C.; Wood, Steven M.; Hanney, Michael B.; Tindale, Wendy B.; Woodhouse, Neil; Hoggard, Nigel; Conway, John; Robinson, Martin H.

    2007-07-01

    Purpose: Head and neck radiotherapy planning with positron emission tomography/computed tomography (PET/CT) requires the images to be reliably registered with treatment planning CT. Acquiring PET/CT in treatment position is problematic, and in practice for some patients it may be beneficial to use diagnostic PET/CT for radiotherapy planning. Therefore, the aim of this study was first to quantify the image registration accuracy of PET/CT to radiotherapy CT and, second, to assess whether PET/CT acquired in diagnostic position can be registered to planning CT. Methods and Materials: Positron emission tomography/CT acquired in diagnostic and treatment position for five patients with head and neck cancer was registered to radiotherapy planning CT using both rigid and nonrigid image registration. The root mean squared error for each method was calculated from a set of anatomic landmarks marked by four independent observers. Results: Nonrigid and rigid registration errors for treatment position PET/CT to planning CT were 2.77 {+-} 0.80 mm and 4.96 {+-} 2.38 mm, respectively, p = 0.001. Applying the nonrigid registration to diagnostic position PET/CT produced a more accurate match to the planning CT than rigid registration of treatment position PET/CT (3.20 {+-} 1.22 mm and 4.96 {+-} 2.38 mm, respectively, p = 0.012). Conclusions: Nonrigid registration provides a more accurate registration of head and neck PET/CT to treatment planning CT than rigid registration. In addition, nonrigid registration of PET/CT acquired with patients in a standardized, diagnostic position can provide images registered to planning CT with greater accuracy than a rigid registration of PET/CT images acquired in treatment position. This may allow greater flexibility in the timing of PET/CT for head and neck cancer patients due to undergo radiotherapy.

  6. Comparison of Intensity-modulated Radiotherapy, Adaptive Radiotherapy, Proton Radiotherapy, and Adaptive Proton Radiotherapy for Treatment of Locally Advanced Head and Neck Cancer

    PubMed Central

    Simone, Charles B.; Ly, David; Dan, Tu D.; Ondos, John; Ning, Holly; Belard, Arnaud; O'Connell, John; Miller, Robert W.; Simone, Nicole L.

    2011-01-01

    Background and Purpose Various radiotherapy planning methods for locally advanced squamous cell carcinoma of the head and neck (SCCHN) have been proposed to decrease normal tissue toxicity. We compare IMRT, adaptive IMRT, proton therapy (IMPT), and adaptive IMPT for SCCHN. Materials and Methods Initial and re-simulation CT images from 10 consecutive patients with SCCHN were used to quantify dosimetric differences between photon and proton therapy. Contouring was performed on both CTs, and plans (n=40 plans) and dose volume histograms were generated. Results The mean GTV volume decreased 53.4% with re-simulation. All plans provided comparable PTV coverage. Compared with IMRT, adaptive IMRT significantly reduced the maximum dose to the mandible (p=0.020) and mean doses to the contralateral parotid gland (p=0.049) and larynx (p=0.049). Compared with IMRT and adaptive IMRT, IMPT significantly lower the maximum doses to the spinal cord (p<0.002 for both) and brainstem (p<0.002 for both) and mean doses to the larynx (p<0.002 for both) and ipsilateral (p=0.004 IMRT, p=0.050 adaptive) and contralateral (p<0.002 IMRT, p=0.010 adaptive) parotid glands. Adaptive IMPT significantly reduced doses to all critical structures compared with IMRT and adaptive IMRT and several critical structures compared with non-adaptive IMPT. Conclusions Although adaptive IMRT reduced dose to several normal structures compared with standard IMRT, non-adaptive proton therapy had a more favorable dosimetric profile than IMRT or adaptive IMRT and may obviate the need for adaptive planning. Protons allowed significant sparing of the spinal cord, parotid glands, larynx, and brainstem and should be considered for SCCHN to decrease normal tissue toxicity while still providing optimal tumor coverage. PMID:21663988

  7. Comparison of intensity-modulated radiotherapy, adaptive radiotherapy, proton radiotherapy, and adaptive proton radiotherapy for treatment of locally advanced head and neck cancer.

    PubMed

    Simone, Charles B; Ly, David; Dan, Tu D; Ondos, John; Ning, Holly; Belard, Arnaud; O'Connell, John; Miller, Robert W; Simone, Nicole L

    2011-12-01

    Various radiotherapy planning methods for locally advanced squamous cell carcinoma of the head and neck (SCCHN) have been proposed to decrease normal tissue toxicity. We compare IMRT, adaptive IMRT, proton therapy (IMPT), and adaptive IMPT for SCCHN. Initial and re-simulation CT images from 10 consecutive patients with SCCHN were used to quantify dosimetric differences between photon and proton therapy. Contouring was performed on both CTs, and plans (n=40 plans) and dose-volume histograms were generated. The mean GTV volume decreased 53.4% with re-simulation. All plans provided comparable PTV coverage. Compared with IMRT, adaptive IMRT significantly reduced the maximum dose to the mandible (p=0.020) and mean doses to the contralateral parotid gland (p=0.049) and larynx (p=0.049). Compared with IMRT and adaptive IMRT, IMPT significantly lowered the maximum doses to the spinal cord (p<0.002 for both) and brainstem (p<0.002 for both) and mean doses to the larynx (p<0.002 for both) and ipsilateral (p=0.004 IMRT, p=0.050 adaptive) and contralateral (p<0.002 IMRT, p=0.010 adaptive) parotid glands. Adaptive IMPT significantly reduced doses to all critical structures compared with IMRT and adaptive IMRT and several critical structures compared with non-adaptive IMPT. Although adaptive IMRT reduced dose to several normal structures compared with standard IMRT, non-adaptive proton therapy had a more favorable dosimetric profile than IMRT or adaptive IMRT and may obviate the need for adaptive planning. Protons allowed significant sparing of the spinal cord, parotid glands, larynx, and brainstem and should be considered for SCCHN to decrease normal tissue toxicity while still providing optimal tumor coverage. Published by Elsevier Ireland Ltd.

  8. Process-based quality management for clinical implementation of adaptive radiotherapy

    SciTech Connect

    Noel, Camille E.; Santanam, Lakshmi; Parikh, Parag J.; Mutic, Sasa

    2014-08-15

    Purpose: Intensity-modulated adaptive radiotherapy (ART) has been the focus of considerable research and developmental work due to its potential therapeutic benefits. However, in light of its unique quality assurance (QA) challenges, no one has described a robust framework for its clinical implementation. In fact, recent position papers by ASTRO and AAPM have firmly endorsed pretreatment patient-specific IMRT QA, which limits the feasibility of online ART. The authors aim to address these obstacles by applying failure mode and effects analysis (FMEA) to identify high-priority errors and appropriate risk-mitigation strategies for clinical implementation of intensity-modulated ART. Methods: An experienced team of two clinical medical physicists, one clinical engineer, and one radiation oncologist was assembled to perform a standard FMEA for intensity-modulated ART. A set of 216 potential radiotherapy failures composed by the forthcoming AAPM task group 100 (TG-100) was used as the basis. Of the 216 failures, 127 were identified as most relevant to an ART scheme. Using the associated TG-100 FMEA values as a baseline, the team considered how the likeliness of occurrence (O), outcome severity (S), and likeliness of failure being undetected (D) would change for ART. New risk priority numbers (RPN) were calculated. Failures characterized by RPN ≥ 200 were identified as potentially critical. Results: FMEA revealed that ART RPN increased for 38% (n = 48/127) of potential failures, with 75% (n = 36/48) attributed to failures in the segmentation and treatment planning processes. Forty-three of 127 failures were identified as potentially critical. Risk-mitigation strategies include implementing a suite of quality control and decision support software, specialty QA software/hardware tools, and an increase in specially trained personnel. Conclusions: Results of the FMEA-based risk assessment demonstrate that intensity-modulated ART introduces different (but not necessarily

  9. Process-based quality management for clinical implementation of adaptive radiotherapy.

    PubMed

    Noel, Camille E; Santanam, Lakshmi; Parikh, Parag J; Mutic, Sasa

    2014-08-01

    Intensity-modulated adaptive radiotherapy (ART) has been the focus of considerable research and developmental work due to its potential therapeutic benefits. However, in light of its unique quality assurance (QA) challenges, no one has described a robust framework for its clinical implementation. In fact, recent position papers by ASTRO and AAPM have firmly endorsed pretreatment patient-specific IMRT QA, which limits the feasibility of online ART. The authors aim to address these obstacles by applying failure mode and effects analysis (FMEA) to identify high-priority errors and appropriate risk-mitigation strategies for clinical implementation of intensity-modulated ART. An experienced team of two clinical medical physicists, one clinical engineer, and one radiation oncologist was assembled to perform a standard FMEA for intensity-modulated ART. A set of 216 potential radiotherapy failures composed by the forthcoming AAPM task group 100 (TG-100) was used as the basis. Of the 216 failures, 127 were identified as most relevant to an ART scheme. Using the associated TG-100 FMEA values as a baseline, the team considered how the likeliness of occurrence (O), outcome severity (S), and likeliness of failure being undetected (D) would change for ART. New risk priority numbers (RPN) were calculated. Failures characterized by RPN ≥ 200 were identified as potentially critical. FMEA revealed that ART RPN increased for 38% (n = 48/127) of potential failures, with 75% (n = 36/48) attributed to failures in the segmentation and treatment planning processes. Forty-three of 127 failures were identified as potentially critical. Risk-mitigation strategies include implementing a suite of quality control and decision support software, specialty QA software/hardware tools, and an increase in specially trained personnel. Results of the FMEA-based risk assessment demonstrate that intensity-modulated ART introduces different (but not necessarily more) risks than standard IMRT and may be

  10. Process-based quality management for clinical implementation of adaptive radiotherapy

    PubMed Central

    Noel, Camille E.; Santanam, Lakshmi; Parikh, Parag J.; Mutic, Sasa

    2014-01-01

    Purpose: Intensity-modulated adaptive radiotherapy (ART) has been the focus of considerable research and developmental work due to its potential therapeutic benefits. However, in light of its unique quality assurance (QA) challenges, no one has described a robust framework for its clinical implementation. In fact, recent position papers by ASTRO and AAPM have firmly endorsed pretreatment patient-specific IMRT QA, which limits the feasibility of online ART. The authors aim to address these obstacles by applying failure mode and effects analysis (FMEA) to identify high-priority errors and appropriate risk-mitigation strategies for clinical implementation of intensity-modulated ART. Methods: An experienced team of two clinical medical physicists, one clinical engineer, and one radiation oncologist was assembled to perform a standard FMEA for intensity-modulated ART. A set of 216 potential radiotherapy failures composed by the forthcoming AAPM task group 100 (TG-100) was used as the basis. Of the 216 failures, 127 were identified as most relevant to an ART scheme. Using the associated TG-100 FMEA values as a baseline, the team considered how the likeliness of occurrence (O), outcome severity (S), and likeliness of failure being undetected (D) would change for ART. New risk priority numbers (RPN) were calculated. Failures characterized by RPN ≥ 200 were identified as potentially critical. Results: FMEA revealed that ART RPN increased for 38% (n = 48/127) of potential failures, with 75% (n = 36/48) attributed to failures in the segmentation and treatment planning processes. Forty-three of 127 failures were identified as potentially critical. Risk-mitigation strategies include implementing a suite of quality control and decision support software, specialty QA software/hardware tools, and an increase in specially trained personnel. Conclusions: Results of the FMEA-based risk assessment demonstrate that intensity-modulated ART introduces different (but not necessarily

  11. Pain and quality of life in patients undergoing radiotherapy for spinal metastatic disease treatment

    PubMed Central

    2013-01-01

    Background Radiotherapy is an important tool in the control of pain in patients with spinal metastatic disease. We aimed to evaluate pain and of quality of life of patients with spinal metastatic disease undergoing radiotherapy with supportive treatment. Methods The study enrolled 30 patients. From January 2008 to January 2010, patients selection included those treated with a 20 Gy tumour dose in five fractions. Patients completed the visual analogue scale for pain assessment and the SF-36 questionnaire for quality of life assessment. Results The most frequent primary sites were breast, multiple myeloma, prostate and lymphoma. It was found that 14 spinal metastatic disease patients (46.66%) had restricted involvement of three or fewer vertebrae, while 16 patients (53.33%) had cases involving more than three vertebrae. The data from the visual analogue scale evaluation of pain showed that the average initial score was 5.7 points, the value 30 days after the end of radiotherapy was 4.60 points and the average value 6 months after treatment was 4.25 points. Notably, this final value was 25.43% lower than the value from the initial analysis. With regard to the quality of life evaluation, only the values for the functional capability and social aspects categories of the questionnaire showed significant improvement. Conclusion Radiotherapy with supportive treatment appears to be an important tool for the treatment of pain in patients with spinal metastatic disease. PMID:23418821

  12. The Development and Evaluation of a Virtual Radiotherapy Treatment Machine Using an Immersive Visualisation Environment

    ERIC Educational Resources Information Center

    Bridge, P.; Appleyard, R. M.; Ward, J. W.; Philips, R.; Beavis, A. W.

    2007-01-01

    Due to the lengthy learning process associated with complicated clinical techniques, undergraduate radiotherapy students can struggle to access sufficient time or patients to gain the level of expertise they require. By developing a hybrid virtual environment with real controls, it was hoped that group learning of these techniques could take place…

  13. Chinese herbal medicines as adjuvant treatment during chemo- or radio-therapy for cancer.

    PubMed

    Qi, Fanghua; Li, Anyuan; Inagaki, Yoshinori; Gao, Jianjun; Li, Jijun; Kokudo, Norihiro; Li, Xiao-Kang; Tang, Wei

    2010-12-01

    Numerous studies have indicated that in cancer treatment Chinese herbal medicines in combination with chemo- or radio-therapy can be used to enhance the efficacy of and diminish the side effects and complications caused by chemo- and radio-therapy. Therefore, an understanding of Chinese herbal medicines is needed by physicians and other health care providers. This review provides evidence for use of Chinese herbal medicines as adjuvant cancer treatment during chemo- or radio-therapy. First, Chinese herbal medicines (e.g. Astragalus, Turmeric, Ginseng, TJ-41, PHY906, Huachansu injection, and Kanglaite injection) that are commonly used by cancer patients for treating the cancer and/or reducing the toxicity induced by chemo- or radio-therapy are discussed. Preclinical and clinical studies have shown that these Chinese herbal medicines possess great advantages in terms of suppressing tumor progression, increasing the sensitivity of chemo- and radio-therapeutics, improving an organism's immune system function, and lessening the damage caused by chemo- and radio-therapeutics. Second, clinical trials of Chinese herbal medicines as adjuvant cancer treatment are reviewed. By reducing side effects and complications during chemo- and radio-therapy, these Chinese herbal medicines have a significant effect on reducing cancer-related fatigue and pain, improving respiratory tract infections and gastrointestinal side effects including diarrhea, nausea, and vomiting, protecting liver function, and even ameliorating the symptoms of cachexia. This review should contribute to an understanding of Chinese herbal medicines as adjuvant treatment for cancer and provide useful information for the development of more effective anti-cancer drugs.

  14. Dosimetric Comparison Between 3-Dimensional Conformal and Robotic SBRT Treatment Plans for Accelerated Partial Breast Radiotherapy.

    PubMed

    Goggin, L M; Descovich, M; McGuinness, C; Shiao, S; Pouliot, J; Park, C

    2016-06-01

    treatment times and 50% lower number of delivered monitor units (MU) were achievable with CyberKnife-multi-leaf collimator than with CyberKnife-Iris. The CyberKnife-multi-leaf collimator treatment times were comparable to 3-dimensional conformal radiotherapy, however, the number of MU delivered was approximately 2.5 times larger. The suitability of 10 + 2 mm margins warrants further investigation. © The Author(s) 2015.

  15. Dosimetric Feasibility of Hypofractionated Proton Radiotherapy for Neoadjuvant Pancreatic Cancer Treatment

    SciTech Connect

    Kozak, Kevin R.; Kachnic, Lisa A.; Adams, Judith C; Crowley, Elizabeth M.; Alexander, Brian M.; Mamon, Harvey J.; Ryan, David P.; DeLaney, Thomas F.; Hong, Theodore S. . E-mail: tshong1@partners.org

    2007-08-01

    Purpose: To evaluate tumor and normal tissue dosimetry of a 5 cobalt gray equivalent (CGE) x 5 fraction proton radiotherapy schedule, before initiating a clinical trial of neoadjuvant, short-course proton radiotherapy for pancreatic adenocarcinoma. Methods and Materials: The first 9 pancreatic cancer patients treated with neoadjuvant intensity-modulated radiotherapy (1.8 Gy x 28) at the Massachusetts General Hospital had treatment plans generated using a 5 CGE x 5 fraction proton regimen. To facilitate dosimetric comparisons, clinical target volumes and normal tissue volumes were held constant. Plans were optimized for target volume coverage and normal tissue sparing. Results: Hypofractionated proton and conventionally fractionated intensity-modulated radiotherapy plans both provided acceptable target volume coverage and dose homogeneity. Improved dose conformality provided by the hypofractionated proton regimen resulted in significant sparing of kidneys, liver, and small bowel, evidenced by significant reductions in the mean doses, expressed as percentage prescribed dose, to these structures. Kidney and liver sparing was most evident in low-dose regions ({<=}20% prescribed dose for both kidneys and {<=}60% prescribed dose for liver). Improvements in small-bowel dosimetry were observed in high- and low-dose regions. Mean stomach and duodenum doses, expressed as percentage prescribed dose, were similar for the two techniques. Conclusions: A proton radiotherapy schedule consisting of 5 fractions of 5 CGE as part of neoadjuvant therapy for adenocarcinoma of the pancreas seems dosimetrically feasible, providing excellent target volume coverage, dose homogeneity, and normal tissue sparing. Hypofractionated proton radiotherapy in this setting merits Phase I clinical trial investigation.

  16. The role of PET in target localization for radiotherapy treatment planning.

    PubMed

    Rembielak, Agata; Price, Pat

    2008-02-01

    Positron emission tomography (PET) is currently accepted as an important tool in oncology, mostly for diagnosis, staging and restaging purposes. It provides a new type of information in radiotherapy, functional rather than anatomical. PET imaging can also be used for target volume definition in radiotherapy treatment planning. The need for very precise target volume delineation has arisen with the increasing use of sophisticated three-dimensional conformal radiotherapy techniques and intensity modulated radiation therapy. It is expected that better delineation of the target volume may lead to a significant reduction in the irradiated volume, thus lowering the risk of treatment complications (smaller safety margins). Better tumour visualisation also allows a higher dose of radiation to be applied to the tumour, which may lead to better tumour control. The aim of this article is to review the possible use of PET imaging in the radiotherapy of various cancers. We focus mainly on non-small cell lung cancer, lymphoma and oesophageal cancer, but also include current opinion on the use of PET-based planning in other tumours including brain, uterine cervix, rectum and prostate.

  17. Does the Time of Radiotherapy Affect Treatment Outcomes? A Review of the Literature.

    PubMed

    Chan, S; Rowbottom, L; McDonald, R; Bjarnason, G A; Tsao, M; Danjoux, C; Barnes, E; Popovic, M; Lam, H; DeAngelis, C; Chow, E

    2017-04-01

    Circadian rhythm-dependent cell cycle progression produces daily variations in radiosensitivity. This literature review aims to summarise the data on whether radiotherapy outcomes differ depending on administration time. A literature search was conducted on Ovid Medline, Embase, Cochrane Central Register of Controlled Trials and PubMed using key words such as 'radiotherapy', 'circadian rhythm', 'treatment outcome' and 'survival'. Articles evaluating the correlation between radiotherapy time and outcomes in cancer patients were included and relevant information was extracted. Nine studies met the inclusion criteria. Four investigated lung cancer patients undergoing stereotactic radiosurgery for brain metastases, with one study observing improved local control and survival in patients treated in the morning. Another two studies with breast and cervical cancer patients observed that the prevalence of toxicities was higher in afternoon and morning cohorts, respectively. Two studies in head and neck cancer patients found trends indicating morning patients experienced less oral mucositis. Increased toxicities and biochemical failure rates were associated with evening treatment in prostate cancer patients. As inconsistencies in the literature exist regarding the time dependency of radiotherapy outcomes, further investigation is warranted.

  18. BEAM: a Monte Carlo code to simulate radiotherapy treatment units.

    PubMed

    Rogers, D W; Faddegon, B A; Ding, G X; Ma, C M; We, J; Mackie, T R

    1995-05-01

    This paper describes BEAM, a general purpose Monte Carlo code to simulate the radiation beams from radiotherapy units including high-energy electron and photon beams, 60Co beams and orthovoltage units. The code handles a variety of elementary geometric entities which the user puts together as needed (jaws, applicators, stacked cones, mirrors, etc.), thus allowing simulation of a wide variety of accelerators. The code is not restricted to cylindrical symmetry. It incorporates a variety of powerful variance reduction techniques such as range rejection, bremsstrahlung splitting and forcing photon interactions. The code allows direct calculation of charge in the monitor ion chamber. It has the capability of keeping track of each particle's history and using this information to score separate dose components (e.g., to determine the dose from electrons scattering off the applicator). The paper presents a variety of calculated results to demonstrate the code's capabilities. The calculated dose distributions in a water phantom irradiated by electron beams from the NRC 35 MeV research accelerator, a Varian Clinac 2100C, a Philips SL75-20, an AECL Therac 20 and a Scanditronix MM50 are all shown to be in good agreement with measurements at the 2 to 3% level. Eighteen electron spectra from four different commercial accelerators are presented and various aspects of the electron beams from a Clinac 2100C are discussed. Timing requirements and selection of parameters for the Monte Carlo calculations are discussed.

  19. Early clinical evaluation of a novel three-dimensional structure delineation software tool (SCULPTER) for radiotherapy treatment planning.

    PubMed

    McBain, C A; Moore, C J; Green, M M L; Price, G; Sykes, J S; Amer, A; Khoo, V S; Price, P

    2008-08-01

    Modern radiotherapy treatment planning (RTP) necessitates increased delineation of target volumes and organs at risk. Conventional manual delineation is a laborious, time-consuming and subjective process. It is prone to inconsistency and variability, but has the potential to be improved using automated segmentation algorithms. We carried out a pilot clinical evaluation of SCULPTER (Structure Creation Using Limited Point Topology Evidence in Radiotherapy) - a novel prototype software tool designed to improve structure delineation for RTP. Anonymized MR and CT image datasets from patients who underwent radiotherapy for bladder or prostate cancer were studied. An experienced radiation oncologist used manual and SCULPTER-assisted methods to create clinically acceptable organ delineations. SCULPTER was also tested by four other RTP professionals. Resulting contours were compared by qualitative inspection and quantitatively by using the volumes of the structures delineated and the time taken for completion. The SCULPTER tool was easy to apply to both MR and CT images and diverse anatomical sites. SCULPTER delineations closely reproduced manual contours with no significant volume differences detected, but SCULPTER delineations were significantly quicker (p<0.05) in most cases. In conclusion, clinical application of SCULPTER resulted in rapid and simple organ delineations with equivalent accuracy to manual methods, demonstrating proof-of-principle of the SCULPTER system and supporting its potential utility in RTP.

  20. Radiotherapy in fascial fibromatosis: a case series, literature review and considerations for treatment of early-stage disease.

    PubMed

    Grenfell, Solveig; Borg, Martin

    2014-10-01

    Palmar and plantar fascial fibromatoses are benign hyperproliferative disorders of the deep fascia of the palm and sole. This study seeks to examine the role of radiotherapy in the management of fascial fibromatosis. Six consecutive cases of early-stage fascial fibromatosis treated with radiotherapy at the Adelaide Radiotherapy Centre between July 2008 and May 2011 were analysed. The results of the case series were compared with a systematic review of the literature. All six cases regressed or showed a reduction of symptoms following radiotherapy. Treatment was well tolerated with minor toxicities. Median follow-up for the case series was 38.5 months. The systematic review identified seven studies describing the use of radiotherapy as primary treatment for fascial fibromatosis between 1946 and 2013. The literature indicates that radiotherapy can prevent disease progression and improve symptoms for early-stage disease, with low likelihood of significant toxicities. Early results from our case series are consistent with the literature, showing that radiotherapy can provide an effective management option for patients with early-stage fascial fibromatosis, and justify consideration of radiotherapy as a primary treatment for early-stage disease. © 2014 The Royal Australian and New Zealand College of Radiologists.

  1. Comparative treatment planning on localized prostate carcinoma conformal photon- versus proton-based radiotherapy.

    PubMed

    Mock, Ulrike; Bogner, Joachim; Georg, Dietmar; Auberger, Thomas; Pötter, Richard

    2005-07-01

    To assess the potential benefit of proton-beam therapy in comparison to 3-D conformal photon therapy and photon- based intensity-modulated radiotherapy (IMRT) in prostate carcinoma for various stages of disease. In five patients a 3-D conformal proton-based (two lateral beams) irradiation technique was compared with 3-D conformal photon-beam radiotherapy (four-field box) and IMRT (seven beams). For each patient different target volumes (CTVs) were defined according to early, intermediate and advanced stages of disease: CTV I consisted of the prostate gland, CTV II encompassed prostate and basis of seminal vesicles, and CTV III the prostate and seminal vesicles. Corresponding planning target volumes PTV I-III were defined by uniformly adding a margin of 5 mm to CTV I-III. Dose-volume histograms (DVHs) were analyzed for the different PTVs and various organs at risk (OARs), i.e., rectal wall, bladder, both femoral heads. In addition, maximum and mean doses were derived for the various structures and irradiated non-target tissue volumes were compared for PTV I-III and the different irradiation techniques. Finally, dose conformity and target dose homogeneity were assessed. With photon- and proton-based radiotherapy techniques similar dose distributions were determined for PTV I-III: mean and maximum PTV dose values were between 99-104% and 102-107% of the normalized total doses (70 Gy), respectively. Conformity indices varied from 1.4 to 1.5 for the photon techniques, whereas for proton-beam radiotherapy values ranged from 1.1 to 1.4. Both the 3-D conformal and the IMRT photon treatment technique resulted in increased mean doses (approximately 40-80%) for OARs when compared to protons. With both photon techniques non-target tissue volumes were irradiated to higher doses (mean dose difference > or = 70%) compared to proton-beam radiotherapy. Differences occurred mainly at the low and medium dose levels, whereas in high dose levels similar values were obtained. In

  2. Celastrol Potentiates Radiotherapy by Impairment of DNA Damage Processing in Human Prostate Cancer

    SciTech Connect

    Dai Yao; DeSano, Jeffrey T.; Meng Yang; J, Qing; Ljungman, Mats; Lawrence, Theodore S.; Xu Liang

    2009-07-15

    Purpose: Celastrol is an active ingredient of traditional herbal medicine and has recently been identified as a potent natural proteasome inhibitor. In the present study, we evaluated the radiosensitizing potential of celastrol in the human prostate cancer PC-3 model. Methods and Materials: Clonogenic assays were performed to determine the radiosensitizing effect of celastrol. Apoptosis was examined by flow cytometry using Annexin V and propidium iodide staining and by a caspase-3 activation assay. DNA damage processing was examined by immunofluorescent staining and Western blot for phosphorylated H2AX ({gamma}H2AX). The PC-3 xenograft model in the athymic nude mouse was used for the determination of the in vivo efficacy of celastrol combined with radiotherapy. The tumor samples were also analyzed for apoptosis and angiogenesis. Results: Celastrol sensitized PC-3 cells to ionizing radiation (IR) in a dose- and schedule-dependent manner, in which pretreatment with celastrol for 1 h followed by IR achieved maximal radiosensitization. Celastrol significantly prolonged the presence of IR-induced {gamma}H2AX and increased IR-induced apoptosis. Celastrol, combined with fractionated radiation, significantly inhibited PC-3 tumor growth in vivo without obvious systemic toxicity. The combination treatment increased {gamma}H2AX levels and apoptosis, induced cleavage of poly(adenosine diphosphate-ribose)polymerase and Mcl-1, and reduced angiogenesis in vivo compared with either treatment alone. Conclusion: Celastrol sensitized PC-3 cells to radiation both in vitro and in vivo by impairing DNA damage processing and augmenting apoptosis. Celastrol might represent a promising new adjuvant regimen for the treatment of hormone-refractory prostate cancer.

  3. Results of radiotherapy and vitamin E in the treatment of Peyronie's disease.

    PubMed

    Rodrigues, C I; Njo, K H; Karim, A B

    1995-02-01

    A retrospective analysis of 38 patients with Peyronie's disease treated with primary radiotherapy in the period of 1975-1993. Important complaints were curvature of the penis during erection for 92% of the patients, painful erection for 68%, and problems with sexual intercourse for 37.5%. Average size of all indurated plaques was 2.5 cm. The average pretreatment duration of symptoms was 9.5 months. All 38 patients were irradiated with orthovoltage radiotherapy (200 and 250 kV photons) with a total dose of 9 Gy in 5 alternating days (regimen A). Because of minimal response, 16 patients were irradiated again with another 9 Gy in 5 days and finally received 18 Gy (regimen B). With regimen A, a satisfying improvement was achieved for the majority of the patients: 65% experienced less penile pain during erection, 40% reported less curvature of the penis, and 47% experienced an improvement of their sex life. With the higher dose of regimen B there was an additional improvement for a minority of the patients: 25% reported less pain during erection, 21% had less curvature, and 29% experienced an improved sex life. With regimen A, pain improvement was statistically significantly superior when compared to regimen B. For all other improvements (curvature, sexual intercourse, and induration) no dose-response relation could be demonstrated between regimen A and the higher dose regimen B. No patient experienced any radiation-induced morbidity. After evaluating regimen A and regimen B, the overall result was that 76% experienced less pain, 60% reported an improved sex life, and 48% had a diminished curvature during erection. From this analysis it can be concluded that the distressing symptoms of Peyronie's disease can be treated successfully with radiotherapy. Radiotherapy proves to be a safe, noninvasive treatment method without causing morbidity. Low-dose radiotherapy with only a few fractions is recommended for an effective treatment result.

  4. Carbon wastewater treatment process

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.

    1974-01-01

    A new powdered-carbon treatment process is being developed for the elimination of the present problems, associated with the disposal of biologically active sewage waste solids, and with water reuse. This counter-current flow process produces an activated carbon, which is obtained from the pyrolysis of the sewage solids, and utilizes this material to remove the adulterating materials from the water. Additional advantages of the process are the elimination of odors, the removal of heavy metals, and the potential for energy conservation.

  5. Carbon wastewater treatment process

    NASA Technical Reports Server (NTRS)

    Humphrey, M. F.; Simmons, G. M.; Dowler, W. L.

    1974-01-01

    A new powdered-carbon treatment process is being developed for the elimination of the present problems, associated with the disposal of biologically active sewage waste solids, and with water reuse. This counter-current flow process produces an activated carbon, which is obtained from the pyrolysis of the sewage solids, and utilizes this material to remove the adulterating materials from the water. Additional advantages of the process are the elimination of odors, the removal of heavy metals, and the potential for energy conservation.

  6. 3D printed facial laser scans for the production of localised radiotherapy treatment masks - A case study.

    PubMed

    Briggs, Matthew; Clements, Helen; Wynne, Neil; Rennie, Allan; Kellett, Darren

    This study investigates the use of 3D printing for patients that require localised radiotherapy treatment to the face. The current process involves producing a lead mask in order to protect the healthy tissue from the effects of the radiotherapy. The mask is produced by applying a thermoplastic sheet to the patient's face and allowing to set hard. This can then be used as a mould to create a plaster impression of the patient's face. A sheet of lead is then hammered on to the plaster to create a bespoke fitted face mask. This process can be distressing for patients and can be problematic when the patient is required to remain motionless for a prolonged time while the thermoplastic sets. In this study, a 1:1 scale 3D print of a patient's face was generated using a laser scanner. The lead was hammered directly on to the surface of the 3D print in order to create a bespoke fitted treatment mask. This eliminated the thermoplastic moulding stage and significantly reduced the time needed for the patient to be in clinic. The higher definition impression of the the face resulted in a more accurate, better fitting treatment mask.

  7. Preoperative radiotherapy in rectal cancer treatment -- is it really a gold standard?

    PubMed

    Pătraşcu, Tr; Doran, H; Mihalache, O

    2014-01-01

    Preoperative radiotherapy in the treatment of rectal cancer was thought to be an achievement of similar importance to total mesorectal excision (TME), for the therapeutic management of rectal malignancies. However, numerous criticisms have been discussed in this field lately. We have analysed the two main purposes of preoperative radiation: possible sphincter preservation and the conversion of a non-resectable tumor into a resectable one in a series of 31 consecutive patients, operated in our clinic. In 20 of them, preoperative radio chemoradiotherapy was applied, while 11 patients were firstly operated and then irradiated. The surgical procedure included total mesorectal excision in 30 patients, as part of a low anterior resection,in 13 cases and of an abdominal perineal resection, in the other 17 cases. We have found that preoperative radiotherapy improves the local recurrence rate but has no influence on the overall survival rate. However, we should not overlook the adverse effects of this method: toxicity of radiotherapy on the small bowel and the urinary bladder, the healing of the perineal wounds and the risk of anastomotic leaks. We concluded in favor of elective preoperative radiotherapy in selected cases: any T4 tumors, T3 tumors which threaten the mesorectal fascia on MRI, whenever there is a suspicion of nodal involvement and also for very low tumors. Celsius.

  8. [Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry].

    PubMed

    Villani, N; Gérard, K; Marchesi, V; Huger, S; François, P; Noël, A

    2010-06-01

    The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (IMRT) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. At Alexis-Vautrin center, pretreatment quality controls in IMRT for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multileaf collimator). Correlation between dose measured at one point, given with the EPID and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. The study allowed to demonstrate the feasibility to reduce the time devoted to

  9. Male Malignant Phyllodes Breast Tumor After Prophylactic Breast Radiotherapy and Bicalutamide Treatment: A Case Report.

    PubMed

    Karihtala, Peeter; Rissanen, Tarja; Tuominen, Hannu

    2016-07-01

    Phyllodes tumor in male breast is an exceptionally rare neoplasm with only few published case reports. Herein, we present a case of malignant phyllodes tumor in male breast nine years after prophylactic breast 10 Gy radiotherapy and after nine year bicalutamide treatment. The imaging findings of the tumor and pathological correlation are also presented. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  10. Three-dimensional power Doppler ultrasound in cervical carcinoma: monitoring treatment response to radiotherapy.

    PubMed

    Huang, Y-F; Cheng, Y-M; Wu, Y-P; Chen, H H W; Hsu, K-F; Wu, Y-H; Chou, C-Y

    2013-07-01

    To investigate, using three-dimensional power Doppler ultrasound (3D-PDU), alterations in cervical intratumoral vascularization during and after radiotherapy. Between 2004 and 2009 we enrolled into the study 37 patients with FIGO Stages IB1-IIB cervical carcinoma who were undergoing radiotherapy. Serial 3D-PDU scans were performed during treatment, providing ultrasonographic measurement of tumor size, vascularization index, flow index and vascularization flow index, as well as monthly for 3 months post-treatment and tri-monthly thereafter, until vascularity was undetectable on two consecutive occasions. Physical examination, cervical cytology and serum marker evaluation were performed every 3-6 months for the first 5 years following treatment. Patients evaluated after a 2-year tumor-free interval and those with clinically assessed positive findings at follow-up underwent 3D-PDU to detect possible local disease. A total of 329 3D-PDU scans were performed in the 37 women. Cervical tumors and intratumoral vascularization disappeared within 3 months following radiotherapy, except in one patient with persistent disease. Nine patients had disease relapse, in four of whom the recurrence was local. In three of these four, there was recurrence of tumor and vascularization after a complete response. At follow-up, 3D-PDU detected local disease with 75.0% sensitivity and 98.5% specificity, while serum markers detected local disease among 34 patients with squamous cell carcinoma with 20.0% sensitivity and 77.3% specificity. Compared with serum markers in cervical squamous cell carcinoma, 3D-PDU has higher sensitivity and specificity for detecting local recurrence or persistence in cervical carcinoma. Thus, 3D-PDU combined with clinical assessment may be a new and safe method for monitoring radiotherapy treatment response and detecting local recurrence. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.

  11. Implications for breast cancer treatment from increased autotaxin production in adipose tissue after radiotherapy.

    PubMed

    Meng, Guanmin; Tang, Xiaoyun; Yang, Zelei; Benesch, Matthew G K; Marshall, Alison; Murray, David; Hemmings, Denise G; Wuest, Frank; McMullen, Todd P W; Brindley, David N

    2017-09-01

    We have previously established that adipose tissue adjacent to breast tumors becomes inflamed by tumor-derived cytokines. This stimulates autotaxin (ATX) secretion from adipocytes, whereas breast cancer cells produce insignificant ATX. Lysophosphatidate produced by ATX promotes inflammatory cytokine secretion in a vicious inflammatory cycle, which increases tumor growth and metastasis and decreases response to chemotherapy. We hypothesized that damage to adipose tissue during radiotherapy for breast cancer should promote lysophosphatidic acid (LPA) signaling and further inflammatory signaling, which could potentially protect cancer cells from subsequent fractions of radiation therapy. To test this hypothesis, we exposed rat and human adipose tissue to radiation doses (0.25-5 Gy) that were expected during radiotherapy. This exposure increased mRNA levels for ATX, cyclooxygenase-2, IL-1β, IL-6, IL-10, TNF-α, and LPA1 and LPA2 receptors by 1.8- to 5.1-fold after 4 to 48 h. There were also 1.5- to 2.5-fold increases in the secretion of ATX and 14 inflammatory mediators after irradiating at 1 Gy. Inhibition of the radiation-induced activation of NF-κB, cyclooxygenase-2, poly (ADP-ribose) polymerase-1, or ataxia telangiectasia and Rad3-related protein blocked inflammatory responses to γ-radiation. Consequently, collateral damage to adipose tissue during radiotherapy could establish a comprehensive wound-healing response that involves increased signaling by LPA, cyclooxygenase-2, and other inflammatory mediators that could decrease the efficacy of further radiotherapy or chemotherapy.-Meng, G., Tang, X., Yang, Z., Benesch, M. G. K., Marshall, A., Murray, D., Hemmings, D. G., Wuest, F., McMullen, T. P. W., Brindley, D. N. Implications for breast cancer treatment from increased autotaxin production in adipose tissue after radiotherapy. © FASEB.

  12. The value of temozolomide in combination with radiotherapy during standard treatment for newly diagnosed glioblastoma.

    PubMed

    Park, Chul-Kee; Lee, Se-Hoon; Kim, Tae Min; Choi, Seung Hong; Park, Sung-Hye; Heo, Dae Seog; Kim, Il Han; Jung, Hee-Won

    2013-04-01

    The current best standard care for glioblastoma still has limitations and unsatisfactory outcomes in patients with an unmethylated O-6-methylguanine-DNA methyltransferase (MGMT) promoter. Whether the effects of temozolomide are primarily due to its concomitant use with radiotherapy or are also mediated by their independent use in the adjuvant phase remain unclear. To validate the concomitant use of temozolomide in the standard protocol, we compared the overall survival of two prospective patient groups: one treated with radiotherapy alone followed by adjuvant temozolomide (RT → TMZ group) and the other treated with concomitant radiotherapy and temozolomide followed by adjuvant temozolomide (CCRT-TMZ group). Each patient in the RT → TMZ group (n = 25) was matched with two patients in the CCRT-TMZ group (n = 50) with respect to age, extent of resection, MGMT promoter methylation status, and postsurgical performance status to minimize the influence of confounding factors. In patients with MGMT promoter methylation, the CCRT-TMZ group showed superior overall survival (OS; median, 41.0 months) and progression-free survival (PFS; median, 24.0 months) compared with the RT → TMZ group. However, the OS and PFS did not differ between the CCRT-TMZ and the RT → TMZ groups in the patients without MGMT promoter methylation. Although this data is from a retrospective analysis using small number of patients, the study might indicate that concomitant use of temozolomide with radiotherapy is a crucial step in the standard treatment for glioblastoma patients with MGMT promoter methylation. And the use of temozolomide, either concurrently or by adjuvant after radiotherapy, remains a questionable value for those with an unmethylated MGMT promoter.

  13. Treatment outcomes after adjuvant radiotherapy following surgery for patients with stage I endometrial cancer.

    PubMed

    Kim, Jiyoung; Lee, Kyung-Ja; Park, Kyung-Ran; Ha, Boram; Kim, Yi-Jun; Jung, Wonguen; Lee, Rena; Kim, Seung Cheol; Moon, Hye Sung; Ju, Woong; Kim, Yun Hwan; Lee, Jihae

    2016-12-01

    The purpose of this study is to evaluate the treatment outcomes of adjuvant radiotherapy using vaginal brachytherapy (VB) with a lower dose per fraction and/or external beam radiotherapy (EBRT) following surgery for patients with stage I endometrial carcinoma. The subjects were 43 patients with the International Federation of Gynecology and Obstetrics (FIGO) stage I endometrial cancer who underwent adjuvant radiotherapy following surgery between March 2000 and April 2014. Of these, 25 received postoperative VB alone, while 18 received postoperative EBRT to the whole pelvis; 3 of these were treated with EBRT plus VB. The median EBRT dose was 50.0 Gy (45.0-50.4 Gy) and the VB dose was 24 Gy in 6 fractions. Tumor dose was prescribed at a depth of 5 mm from the cylinder surface and delivered twice per week. The median follow-up period for all patients was 57 months (range, 9 to 188 months). Five-year disease-free survival (DFS) and overall survival (OS) for all patients were 92.5% and 95.3%, respectively. Adjuvant radiotherapy was performed according to risk factors and stage IB, grade 3 and lymphovascular invasion were observed more frequently in the EBRT group. Five-year DFS for EBRT and VB alone were 88.1% and 96.0%, respectively (p = 0.42), and 5-year OS for EBRT and VB alone were 94.4% and 96%, respectively (p = 0.38). There was no locoregional recurrence in any patient. Two patients who received EBRT and 1 patient who received VB alone developed distant metastatic disease. Two patients who received EBRT had severe complications, one each of grade 3 gastrointestinal complication and pelvic bone insufficiency fracture. Adjuvant radiotherapy achieved high DFS and OS with acceptable toxicity in stage I endometrial cancer. VB (with a lower dose per fraction) may be a viable option for selected patients with early-stage endometrial cancer following surgery.

  14. Evaluation of the Radiotherapy Treatment Planning in the Presence of a Magnetic Valve Tissue Expander

    PubMed Central

    Trombetta, Débora M.; Cardoso, Simone C.; Alves, Victor G. L.; Facure, Alessandro; Batista, Delano V. S.; da Silva, Ademir X.

    2015-01-01

    The combination of radiotherapy treatments and breast reconstruction, using temporary tissue expanders, generates several concerns due to the presence of a magnetic valve inside the radiation field. The objective of this work is to evaluate a radiotherapy treatment planning for a patient using a tissue expander. Isodose curve maps, obtained using radiochromic films, were compared to the ones calculated with two different dose calculation algorithms of the Eclipse radiotherapy Treatment Planning System (TPS), considering the presence or absence of the heterogeneity. The TPS calculation considering the presence of the heterogeneity shows changes around 5% in the isodose curves when they were compared with the calculation without heterogeneity correction. This calculation did not take in account the real density value of the heterogeneity. This limitation was quantified to be around 10% in comparison with the TPS calculation and experimental measurements using the radiochromic film. These results show that the magnetic valve should be taken in account in dose calculations of the TPS. With respect to the AAA and Pencil Beam Convolution algorithms, when the calculation is compared with the real distribution, AAA presents a distribution more similar to experimental dose distribution. PMID:25679529

  15. Telemedicine in radiotherapy: a study exploring remote treatment planning, supervision and economics.

    PubMed

    Norum, Jan; Bruland, Øyvind S; Spanne, Oddvar; Bergmo, Trine; Green, Tor; Olsen, Dag R; Olsen, Jan H; Sjåeng, Elisabeth E; Burkow, Tatiana

    2005-01-01

    In January 2002, the departments of radiotherapy at the University Hospital of North Norway and the Norwegian Radium Hospital were connected through a 2 Mbit/s digital telecommunication line. The treatment planning systems at the two institutions were connected and videoconferencing units were installed. We explored the feasibility of remote treatment planning, supervision, second opinions and education. Tests involved two dummy cases and six patients. Remote simulation procedures were carried out for five patients. A cost-minimization analysis was performed. Treatment planning was not completely successful as the software could not handle plans including bolus or weighting between the fields. Remote supervision was possible. A common patient record and radiotherapy system, including digital imaging, digital prescription and approval forms and digital signature, were felt to be desirable. The threshold (break-even point) comparing the costs of telemedicine with those of transportation by air was 12 patients/year. Telemedicine in radiotherapy appears to be feasible, but some limitations must be overcome.

  16. MR Imaging Based Treatment Planning for Radiotherapy of Prostate Cancer

    DTIC Science & Technology

    2008-02-01

    C-M Ma. Benefit of three-dimensional image-guided stereotactic localization in the hypofractionated treatment of lung cancer. International... hypofractionated treatment of lung cancer. Medical Physics, 2006; 33: 1993 11. Chen Z, Ma C, Li J, Paskalev K, Price R, Luo W, Fan J, Stathakis S, Chen Y, Lin T...study for clinical implementation of dose hypofractionation with IMRT for prostate cancer. Proc. Medical Physics, 31(6), 1788, 2004. Lili Chen

  17. SU-E-T-148: Efficient Verification Method for Modulated Electron Radiotherapy Treatment Plans

    SciTech Connect

    Henzen, D; Chatelain, C; Manser, P; Frei, D; Volken, W; Joosten, A; Loessl, K; Aebersold, D M; Fix, M K; Neuenschwander, H

    2014-06-01

    Purpose: For shallow tumors, modulated electron radiotherapy (MERT) promises a reduction of dose to distal organs at risk. At our institution a framework was developed in order to create treatment plans for MERT employing both forward and inverse optimization. In this work, an efficient quality assurance (QA) process is established. Methods: Treatment plans for three different tumor sites were created using an inverse optimization. These plans consist of 6–12 segments and energies between 6 and 18 MeV. An already established QA process for photon IMRT plans is now extended to additionally handle MERT plans. First, the dose distributions are calculated in a homogenous water phantom. For this task a dedicated Monte Carlo (MC) framework for MERT is used. Second, the segments are applied on a stand-alone amorphous silicon electronic portal imaging device (EPID) using a source-to-surface distance of 70 cm. This device was calibrated for electron beams in a previous work. An in-house developed analysis software, is then utilized for comparisons and evaluation of the measured and calculated dose distributions. Results: For all three plans the calculated dose distributions agree well with the measured ones. Using a 2D gamma comparison (2% of dose max/2 mm and 10% dose threshold) passing rates >98% are achieved.The dose calculation for each plan on the water phantom, using voxels of 0.2×0.2×0.2 cm{sup 3}, takes at maximum 30 min on a single core Pentium 2.66 GHz system with 6 GB RAM, to reach a statistical uncertainty of 2% (1 std. dev.). Conclusion: An already established QA procedure for IMRT photon plans was applied for MERT. The dedicated MC framework and the use of EPID measurements allow an efficient QA procedure in a clinical environment. This work was supported by Varian Medical Systems.

  18. [Laryngeal conservative surgery in patients candidates for combined treatment with chemo-radiotherapy].

    PubMed

    Gallegos-Hernández, José Francisco; Cruz-Esquivel, Iván; Ortiz-Maldonado, Alma Lilia; Minauro-Muñoz, Gerardo Gabriel; Arias-Ceballos, Héctor; Pichardo-Romero, Pablo

    2016-01-01

    The standard of care for advanced-stage laryngeal cancer is combined treatment (chemo-radiotherapy). However, the complications with this treatment are not few, mainly in swallowing. Conservative laryngeal surgery remains an effective alternative for cancer control without the complications of chemo-radiotherapy. Retrospective study was conducted on patients with laryngeal cancer cT3, cN0 with paraglottic infiltration, fixation of the vocal cord, minimal invasion of the hyo-thyroepiglottic space, but with normal arytenoid mobility and no sub-glottic extension, were treated with subtotal supracricoid laryngectomy. Complications, sequels of treatment, and local recurrence were evaluated. Bronchial aspiration was studied with radioactive swallow. There were 25 patients, 22 with negative surgical margins, one had tumour contact with the surgical margins, and 2 were positive. Two patients received postoperative radiotherapy. The mean decannulation was 15 days and removal of nasogastric tube 25 days. During the mean follow-up of 26 months, none of the patients had tumour recurrence or required conversion to total laryngectomy. In all patients swallowing has been normal and none required permanent or temporary tracheotomy or definitive gastrostomy. The voice is considered intelligible in all patients. Radioactive swallow showed aspiration in 15/25 patients, with none being clinically relevant. There were postoperative complications in 5 patients, and 4 patients required re-intervention but no conversion to total laryngectomy. Conservative surgery is an effective surgical-alternative to chemo-radiotherapy in patients with locally advanced laryngeal cancer, providing oncological control, acceptable complications and minimal sequels. Although most patients have aspiration, this does not affect functional status. Copyright © 2015. Published by Masson Doyma México S.A.

  19. Treatment-related toxicity and symptom-related bother following postoperative radiotherapy for prostate cancer

    PubMed Central

    Sia, Michael; Rodrigues, George; Menard, Cynthia; Bayley, Andrew; Bristow, Robert; Chung, Peter; Gospodarowicz, Mary; Milosevic, Michael; Warde, Padraig; Catton, Charles

    2010-01-01

    Introduction: Patients have reported late effects and symptom-related bother following postoperative radiotherapy for prostate cancer. Methods: Patients treated with postoperative radiotherapy were surveyed at a median 56 months after radiotherapy using the Prostate Cancer Radiation Therapy instrument. A retrospective review was undertaken to obtain Radiation Therapy Oncology Group-Late Effects Normal Tissue (RTOG-LENT) toxicity scores at baseline and during follow-up. Results: Survey response was 64.5%. Median prostate bed radiation dose was 66 Gy given at a median 14 months after surgery. Adjuvant hormone therapy was given for 2 to 3 years to 40 patients; 22 received salvage therapy. PCRT impairment subscales were reported as mild for gastrointestinal dysfunction, moderate for genitourinary dysfunction and marked for sexual dysfunction. The use of one or more incontinence pads daily was reported by 25.6% and was similar to 23% use reported at baseline. Frequent or worse urinary frequency or hematuria was reported by 4.8%, and by 8.4% of respondents for bowel dysfunction. Moderate to severe disruption from bowel and bladder dysfunction was reported by up to 5.4% and 2.4% of respondents, respectively. Erectile function was described as poor to none in 88.3% of respondents, and dissatisfaction with sexual functioning was reported by 42.7%. Counselling or treatment was offered to 59% of those followed. Conclusion: Combined surgery and postoperative radiotherapy are associated with low and moderate rates of bowel and bladder dysfunction respectively, with low reported bother. High levels of sexual dysfunction and bother are seen following combined therapy. More effective pre- and post-treatment counselling are required, along with research into more effective prevention and treatment strategies. PMID:20368892

  20. PET/CT for Radiotherapy Treatment Planning in Patients With Soft Tissue Sarcomas

    SciTech Connect

    Karam, Irene; Devic, Slobodan; Hickeson, Marc; Roberge, David; Turcotte, Robert E.; Freeman, Carolyn R.

    2009-11-01

    Purpose: To study the possibility of incorporating positron emission tomography/computed tomography (PET/CT) information into radiotherapy treatment planning in patients with high-grade soft tissue sarcomas (STS). Methods and Materials: We studied 17 patients treated with preoperative radiotherapy at our institution from 2005 to 2007. All patients had a high-grade STS and had had a staging PET/CT scan. For each patient, an MRI-based gross tumor volume (GTV), considered to be the contemporary standard for radiotherapy treatment planning, was outlined on a T1-gadolinium enhanced axial MRI (GTV{sub MRI}), and a second set of GTVs were outlined using different threshold values on PET images (GTV{sub PET}). PET-based target volumes were compared with the MRI-based GTV. Threshold values for target contouring were determined as a multiple (from 2 to 10 times) of the background soft tissue uptake values (B) sampled over healthy tissue. Results: PET-based GTVs contoured using a threshold value of 2 or 2.5 most closely resembled the GTV{sub MRI} volumes. Higher threshold values lead to PET volumes much smaller than the GTV{sub MRI}. The standard deviations between the average volumes of GTV{sub PET} and GTV{sub MRI} ratios for all thresholds were large, ranging from 36% for 2 xB up to 93% for 10 xB. Maximum uptake-to-background ratio correlated poorly with the maximum standardized uptake values. Conclusions: It is unlikely that PET/CT will make a significant contribution in GTV definition for radiotherapy treatment planning in patients with STS using threshold methods on PET images. Future studies will focus on molecular imaging and tumor physiology.

  1. Three-dimensional conformal radiotherapy in the treatment of prostate cancer in Australia and New Zealand: Report on a survey of radiotherapy centres and the proceedings of a consensus workshop.

    PubMed

    Tai, K-H; Duchesne, G; Turner, S; Kneebone, A; See, A; Gogna, K; Berry, M

    2004-12-01

    There is an increasing use of 3-D conformal radiotherapy (3DCRT) in the radiotherapeutic management of prostate cancer. The Faculty of Radiation Oncology Genito-Urinary Group carried out a survey of Australian and New Zealand radiotherapy centres in the preparation of a consensus workshop. Of the 19 centres that were represented, there were 24 radiation oncologists, 16 radiation therapists and 12 medical physicists. The survey collected demographic information and data on the practices undertaken at those centres when delivering curative radiotherapy in the treatment of prostate cancer. There was much variation in the delivery of treatment in the areas of patient set-up, contouring of target volumes and organs of interest during computer planning, the techniques and the dose constraints used in these techniques, the use of adjuvant androgen deprivation therapy and the quality assurance processes used in monitoring effects of treatment. This variability reflects the range of data in the published literature. Emerging trends of practices were also identified. This is a first report on a multi-disciplinary approach to the development of guidelines in 3DCRT of prostate cancer.

  2. Integration of second cancer risk calculations in a radiotherapy treatment planning system

    NASA Astrophysics Data System (ADS)

    Hartmann, M.; Schneider, U.

    2014-03-01

    Second cancer risk in patients, in particular in children, who were treated with radiotherapy is an important side effect. It should be minimized by selecting an appropriate treatment plan for the patient. The objectives of this study were to integrate a risk model for radiation induced cancer into a treatment planning system which allows to judge different treatment plans with regard to second cancer induction and to quantify the potential reduction in predicted risk. A model for radiation induced cancer including fractionation effects which is valid for doses in the radiotherapy range was integrated into a treatment planning system. From the three-dimensional (3D) dose distribution the 3D-risk equivalent dose (RED) was calculated on an organ specific basis. In addition to RED further risk coefficients like OED (organ equivalent dose), EAR (excess absolute risk) and LAR (lifetime attributable risk) are computed. A risk model for radiation induced cancer was successfully integrated in a treatment planning system. Several risk coefficients can be viewed and used to obtain critical situations were a plan can be optimised. Risk-volume-histograms and organ specific risks were calculated for different treatment plans and were used in combination with NTCP estimates for plan evaluation. It is concluded that the integration of second cancer risk estimates in a commercial treatment planning system is feasible. It can be used in addition to NTCP modelling for optimising treatment plans which result in the lowest possible second cancer risk for a patient.

  3. [Corticosteroids and radiotherapy in the treatment of Graves' ophthalmopathy].

    PubMed

    Nasr, Elie; Khater, Sherine; Nehme-Nasr, Dolly; Azoury, Fares; Jambart, Selim

    2010-01-01

    Graves' ophthalmopathy is a debilitating disease impairing the quality of life of affected individuals. The management of moderate-to-severe active Graves' ophthalmopathy is a major therapeutic challenge, and the treatment outcome is often unsatisfactory. We have carried out a retrospective study to assess the efficacy of combined orbital irradiation and systemic corticosteroids. Ten patients were included; all patients had received 20 Grays to the retrobulbar tissues in ten fractions, and oral or intravenous glucocorticoids. The main therapeutic outcome measures were the criteria of Donaldson and co-workers and a self-assessment evaluation. The quality of life outcome was also evaluated by the GO-QOL (Graves' ophthalmopathy quality of life) questionnaire. Seven patients (70%) demonstrated improvement in ocular parameters; the response was excellent in three cases, good in three cases and fair in one case. Three patients showed no response to the treatment. The self-assessment evaluation showed that 75% of patients were satisfied with the results of the treatment. Proptosis was the most responsive sign to radiation and steroids. A duration of the eye disease of more than 18 months was associated with less improvement and a higher failure of the treatment. Concerning the quality of life, the score for visual fonctionning was 882 +/- 18.2 after treatment, while the score for appearance was 63.3 +/- 23.3. In conclusion, a combination of orbital irradiation and systemic steroids is associated with 70% of favorable responses, but the quality of life is not restored in the same proportions and remains impaired after treatment.

  4. Similar Treatment Outcomes for Radical Cystectomy and Radical Radiotherapy in Invasive Bladder Cancer Treated at a United Kingdom Specialist Treatment Center

    SciTech Connect

    Kotwal, Sanjeev; Choudhury, Ananya; Johnston, Colin; Paul, Alan B.; Whelan, Peter; Kiltie, Anne E.

    2008-02-01

    Purpose: To conduct a retrospective analysis within a large university teaching hospital, comparing outcomes between patients receiving either radical surgery or radiotherapy as curative treatment for bladder cancer. Patients and Methods: Between March 1996 and December 2000, 169 patients were treated radically for muscle-invasive bladder cancer. Data were collected from patient notes. Statistical analyses were performed using Kaplan-Meier methods and Cox proportional hazards regression analysis to compare radiotherapy and surgical outcome data. Results: There was no difference in overall, cause-specific, and distant recurrence-free survival at 5 years between the two groups, despite the radiotherapy group being older (median age, 75.3 years vs. 68.2 years). There were 31 local bladder recurrences in the radiotherapy group (24 solitary), but there was no significant difference in distant recurrence-free survival. In a more recent (2002-2006) cohort, the median age of radiotherapy patients but not the cystectomy patients was higher than in the 1996-2000 cohort (78.4 years vs. 75.3 years for radiotherapy and 67.9 years vs. 68.2 years for surgery). Conclusions: Although the patients undergoing radical cystectomy were significantly younger than the radiotherapy patients, treatment modality did not influence survival. Bladder cancer patients are an increasingly elderly group. Radical radiotherapy is a viable treatment option for these patients, with the advantage of organ preservation.

  5. Intraoperative Radiotherapy for Breast Cancer: The Lasting Effects of a Fleeting Treatment

    PubMed Central

    Rosenberg, Anne L.

    2014-01-01

    In well-selected patients who choose to pursue breast conservation therapy (BCT) for early-stage breast cancer, partial breast irradiation (PBI) delivered externally or intraoperatively, may be a viable alternative to conventional whole breast irradiation. Two large, contemporary randomized trials have demonstrated breast intraoperative radiotherapy (IORT) to be noninferior to whole breast external beam radiotherapy (EBRT) when assessing for ipsilateral breast tumor recurrence in select patients. Additionally, IORT and other PBI techniques are likely to be more widely adopted in the future because they improve patient convenience by offering an accelerated course of treatment. Coupled with these novel techniques for breast radiotherapy (RT) are distinct toxicity profiles and unique cosmetic alterations that differ from conventional breast EBRT and have the potential to impact disease surveillance and patient satisfaction. This paper will review the level-one evidence for treatment efficacy as well as important secondary endpoints like RT toxicity, breast cosmesis, quality of life, patient satisfaction, and surveillance mammography following BCT with IORT. PMID:25180098

  6. Monte Carlo simulation of the photoneutron field in linac radiotherapy treatments with different collimation systems

    NASA Astrophysics Data System (ADS)

    Zanini, A.; Durisi, E.; Fasolo, F.; Ongaro, C.; Visca, L.; Nastasi, U.; Burn, K. W.; Scielzo, G.; Adler, J. O.; Annand, J. R. M.; Rosner, G.

    2004-02-01

    Bremsstrahlung photon beams produced by linac accelerators are currently the most commonly used method of radiotherapy for tumour treatments. When the photon energy exceeds 10 MeV the patient receives an undesired dose due to photoneutron production in the accelerator head. In the last few decades, new sophisticated techniques such as multileaf collimators have been used for a better definition of the target volume. In this case it is crucial to evaluate the photoneutron dose produced after giant dipole resonance (GDR) excitation of the high Z materials (mainly tungsten and lead) constituting the collimator leaves in view of the optimization of the radiotherapy treatment. A Monte Carlo approach has been used to calculate the photoneutron dose arising from the GDR reaction during radiotherapy with energetic photon beams. The simulation has been performed using the code MCNP4B-GN which is based on MCNP4B, but includes a new routine GAMMAN to model photoneutron production. Results for the facility at IRCC (Istituto per la Ricerca e la Cura del Cancro) Candiolo (Turin), which is based on 18 MV x-rays from a Varian Clinac 2300 C/D, are presented for a variety of different collimator configurations.

  7. Prevention and treatment of chemo- and radiotherapy-induced oral mucositis.

    PubMed

    Demarosi, F; Bez, C; Carrassi, A

    2002-05-01

    The administration of many chemo-radiotherapy regimens in patients with cancer may be complicated by toxicities that limit the clinicians' abilities to deliver the most effective doses of active agents. Oral mucositis is a major dose-limiting toxic effect and the most important cause of morbidity in patients undergoing chemo-radiotherapy for head and neck cancers, in patients undergoing bone marrow transplantation and those receiving certain chemotherapeutic agents for a variety of human malignancies. The intent of this paper is to review preventive strategies and treatment approaches for patients with established oral mucositis. Many agents of differing mechanisms of action have been used in the prevention and treatment of oral mucositis induced by anticancer therapies. Currently, no intervention is completely successful at preventing or treating oral mucositis. The several solutions, drugs and methods used and studied in the prophylaxis and therapy of chemotherapy or radiotherapy-induced oral mucositis reflects the need of new, more efficient tools in the management of this complication. Current studies and our increasing understanding of the etiology and pathogenesis of oral mucositis will lead to new approaches to the management and improved quality of life for these patients.

  8. Monte Carlo simulation of the photoneutron field in linac radiotherapy treatments with different collimation systems.

    PubMed

    Zanini, A; Durisi, E; Fasolo, F; Ongaro, C; Visca, L; Nastasi, U; Burn, K W; Scielzo, G; Adler, J O; Annand, J R M; Rosner, G

    2004-02-21

    Bremsstrahlung photon beams produced by linac accelerators are currently the most commonly used method of radiotherapy for tumour treatments. When the photon energy exceeds 10 MeV the patient receives an undesired dose due to photoneutron production in the accelerator head. In the last few decades, new sophisticated techniques such as multileaf collimators have been used for a better definition of the target volume. In this case it is crucial to evaluate the photoneutron dose produced after giant dipole resonance (GDR) excitation of the high Z materials (mainly tungsten and lead) constituting the collimator leaves in view of the optimization of the radiotherapy treatment. A Monte Carlo approach has been used to calculate the photoneutron dose arising from the GDR reaction during radiotherapy with energetic photon beams. The simulation has been performed using the code MCNP4B-GN which is based on MCNP4B, but includes a new routine GAMMAN to model photoneutron production. Results for the facility at IRCC (Istituto per la Ricerca e la Cura del Cancro) Candiolo (Turin), which is based on 18 MV x-rays from a Varian Clinac 2300 C/D, are presented for a variety of different collimator configurations.

  9. Intracatheter hyperthermia and iridium-192 radiotherapy in the treatment of bile duct carcinoma.

    PubMed

    Wong, J Y; Vora, N L; Chou, C K; McDougall, J A; Chan, K W; Findley, D O; Forell, B W; Luk, K H; Philben, V J; Beatty, J D

    1988-02-01

    We report a case of a patient with locally advanced bile duct carcinoma treated with 4500 cGy external beam radiotherapy, followed 3 weeks later by intracatheter 915 MHz microwave hyperthermia and radiotherapy delivered through a biliary U-tube placed at the time of surgery. Heating was to 43-45 degrees C for 1 hour followed immediately by intracatheter Iridium-192 seeds to deliver 5000 cGy over a 72 hour period. Prior to treatment, a thermal dosimetry study in phanton was conducted, using the same type of U-tube catheter tubing as in the patient. Orthogonal X rays of the patient's porta hepatis region were used to reconstruct the catheter geometry in the phantom. Proper insertion depth was determined thermographically to obtain maximum heating at the center of the tumor. The maximum SAR was 8.8 watts per kilogram per watt input. During the treatment, the average power applied was 30 W. Six months after therapy, the patient is asymptomatic. Although alkaline phosphatase, SGOT and SGPT have remained elevated, bilirubin has returned to normal and computerized tomographic scans and cholangiograms remain stable. A duodenal ulcer developed after therapy and is healing well with conservative medical management. This case demonstrates that hyperthermia applied through biliary drainage catheters is technically feasible and clinically tolerated. We believe the use of intracatheter hyperthermia in conjunction with external and/or intracatheter radiotherapy in selected patients with unresectable bile duct carcinomas warrants further study.

  10. Low-Dose Involved-Field Radiotherapy as Alternative Treatment of Nodular Lymphocyte Predominance Hodgkin's Lymphoma

    SciTech Connect

    Haas, Rick L.M. Girinsky, Theo; Aleman, Berthe; Henry-Amar, Michel; Boer, Jan-Paul de; Jong, Daphne de

    2009-07-15

    Purpose: Nodular lymphocyte predominance Hodgkin's lymphoma is a very rare disease, characterized by an indolent clinical course, with sometimes very late relapses occurring in a minority of all patients. Considerable discussion is ongoing on the treatment of primary and relapsed disease. Patients and Methods: A group of 9 patients were irradiated to a dose of 4 Gy on involved areas only. Results: After a median follow-up of 37 months (range, 6-66), the overall response rate was 89%. Six patients had complete remission (67%), two had partial remission (22%), and one had stable disease (11%). Of 8 patients, 5 developed local relapse 9-57 months after radiotherapy. No toxicity was noted. Conclusion: In nodular lymphocyte predominance Hodgkin's lymphoma, low-dose radiotherapy provided excellent response rates and lasting remissions without significant toxicity.

  11. Postoperative Radiotherapy for the Treatment of Solitary Fibrous Tumor With Malignant Transformation of the Pelvic

    PubMed Central

    Gao, Chao; Zhang, Yong; Jing, Ming; Qu, Wei; Li, Jia; Zhao, Xiang-Rong; Yu, Yong-Hua

    2016-01-01

    Abstract Solitary fibrous tumor of the pelvic is an uncommon neoplasm with nonspecific symptoms. Reports of malignant transformation are especially rare. We report a case of solitary fibrous tumor in pelvic. A unique feature of our case compared with previously reported is that this patient relapsed with malignant transformation and had significant response to radiotherapy. The patient was initially treated with surgery, followed by postoperative dimensional conformal intensity modulated radiation therapy (dynamic MLC VRIAN 23EX Linac, inversely optimized by the Eclipse system) to provide a radical cure for residual tumor. In this case, there were no signs of recurrence after six and a half years of further follow-up, indicating that postoperation radiotherapy may be an effective treatment for SFT with malignant transformation in pelvic. PMID:26765426

  12. [Case report: a gastrectomized patient under treatment with chemotherapy and radiotherapy].

    PubMed

    Cañones Castelló, María Estrella

    2008-01-01

    The adjuvant treatment of gastric cancer includes radiotherapy and chemotherapy. The patient underwent gastrectomy on November 10, 2006 and began adjuvant chemotherapy (McDonald scheme) on january 2, 2007, finishing on june 1, 2007. Radiotherapy was started on February 6, 2007 and finished on March 16, 2007. The care plan presented was designed following the Virginia Henderson model and is routinely used at the Reina Sofía Hospital. This care plan follows the NANDA, NOC and NIC taxonomies and is based on the following nursing diagnoses: risk of infection, fear, and disposition to improve knowledge. During the clinical course, two new nursing diagnoses were identified: deterioration of oral mucosa and skin integrity.

  13. Dose calculation accuracies in whole breast radiotherapy treatment planning: a multi-institutional study.

    PubMed

    Hatanaka, Shogo; Miyabe, Yuki; Tohyama, Naoki; Kumazaki, Yu; Kurooka, Masahiko; Okamoto, Hiroyuki; Tachibana, Hidenobu; Kito, Satoshi; Wakita, Akihisa; Ohotomo, Yuko; Ikagawa, Hiroyuki; Ishikura, Satoshi; Nozaki, Miwako; Kagami, Yoshikazu; Hiraoka, Masahiro; Nishio, Teiji

    2015-07-01

    Our objective in this study was to evaluate the variation in the doses delivered among institutions due to dose calculation inaccuracies in whole breast radiotherapy. We have developed practical procedures for quality assurance (QA) of radiation treatment planning systems. These QA procedures are designed to be performed easily at any institution and to permit comparisons of results across institutions. The dose calculation accuracy was evaluated across seven institutions using various irradiation conditions. In some conditions, there was a >3 % difference between the calculated dose and the measured dose. The dose calculation accuracy differs among institutions because it is dependent on both the dose calculation algorithm and beam modeling. The QA procedures in this study are useful for verifying the accuracy of the dose calculation algorithm and of the beam model before clinical use for whole breast radiotherapy.

  14. The efficacy of orgotein in the treatment of acute toxicity due to radiotherapy on head and neck tumors.

    PubMed

    Valencia, Javier; Velilla, Carmen; Urpegui, Angel; Alvarez, Ignacio; Llorens, M Angeles; Coronel, Pilar; Polo, Sonia; Bascón, Natividad; Escó, Ricardo

    2002-01-01

    To assess the efficacy of orgotein in the treatment of acute secondary effects of radiotherapy on head and neck tumors. Data were collected on 41 patients who received radiotherapy for tumors of the head and neck. Radiotherapy was the exclusive treatment in 19.5% of cases, with surgery in 24.4%, chemotherapy in 48.8%, and with both in 7.3%. The toxicity requiring use of orgotein was: oropharynx mucositis (26.8%), dysphagia (34.2%), or both (39%), in grade 2 or more according to the RTOG scale. Orgotein (8 mg i.m.) was administered every 48 hrs until radiotherapy was finished. The overall response rate was 92.5%; a complete response was obtained in 12 patients (30%) and partial in 25 (62.5%). The reduction in toxicity at the end of radiotherapy was one grade in 18 patients (45%), 2 grades in 16 (40%), 3 in 2 patients (5%), and 4 grades in the only patient with grade 4 acute toxicity. A statistically significant influence was shown in obtaining complete response: laryngeal tumor location (P = 0.037), duration of radiotherapy of more than 53 days (P = 0.002), discontinuation for non-toxic reasons (P = 0.008). We consider that orgotein is highly effective in dealing with acute secondary effects of radiotherapy on the head and neck area.

  15. Treatment Planning Study to Determine Potential Benefit of Intensity-Modulated Radiotherapy Versus Conformal Radiotherapy for Unresectable Hepatic Malignancies

    SciTech Connect

    Eccles, Cynthia L.; Bissonnette, Jean-Pierre; Craig, Tim; Taremi, Mojgan; Wu Xia; Dawson, Laura A.

    2008-10-01

    Purpose: To compare intensity-modulated radiotherapy (IMRT) with conformal RT (CRT) for hypofractionated isotoxicity liver RT and explore dose escalation using IMRT for the same/improved nominal risk of liver toxicity in a treatment planning study. Methods and Materials: A total of 26 CRT plans were evaluated. Prescription doses (24-54 Gy within six fractions) were individualized on the basis of the effective liver volume irradiated maintaining {<=}5% risk of radiation-induced liver disease. The dose constraints included bowel (0.5 cm{sup 3}) and stomach (0.5 cm{sup 3}) to {<=}30 Gy, spinal cord to {<=}25 Gy, and planning target volume (PTV) to {<=}140% of the prescribed dose. Two groups were evaluated: (1) PTV overlapping or directly adjacent to serial functioning normal tissues (n = 14), and (2) the liver as the dose-limiting normal tissue (n = 12). IMRT plans using direct machine parameter optimization maintained the CRT plan beam arrangements, an estimated radiation-induced liver disease risk of 5%, and underwent dose escalation, if all normal tissue constraints were maintained. Results: IMRT improved PTV coverage in 19 of 26 plans (73%). Dose escalation was feasible in 9 cases by an average of 3.8 Gy (range, 0.6-13.2) in six fractions. Three of seven plans without improved PTV coverage had small gross tumor volumes ({<=}105 cm{sup 3}) already receiving 54 Gy, the maximal prescription dose allowed. In the remaining cases, the PTV range was 9.6-689 cm{sup 3}; two had overlapped organs at risk; and one had four targets. IMRT did not improve these plans owing to poor target coverage (n = 2) and nonliver (n = 2) dose limits. Conclusion: Direct machine parameter optimization IMRT improved PTV coverage while maintaining normal tissue tolerances in most CRT liver plans. Dose escalation was possible in a minority of patients.

  16. Involved-Node Radiotherapy and Modern Radiation Treatment Techniques in Patients With Hodgkin Lymphoma

    SciTech Connect

    Paumier, Amaury; Ghalibafian, Mithra; Beaudre, Anne; Ferreira, Ivaldo; Pichenot, Charlotte; Messai, Taha; Lessard, Nathalie Athalie; Lefkopoulos, Dimitri; Girinsky, Theodore

    2011-05-01

    Purpose: To assess the clinical outcome of the involved-node radiotherapy (INRT) concept using modern radiation treatments (intensity-modulated radiotherapy [IMRT]or deep-inspiration breath-hold radiotherapy [DIBH) in patients with localized supradiaphragmatic Hodgkin lymphoma. Methods and Materials: All but 2 patients had early-stage Hodgkin lymphoma, and they were treated with chemotherapy prior to irradiation. Radiation treatments were delivered using the INRT concept according to European Organization for Research and Treatment of Cancer guidelines. IMRT was performed with the patient free-breathing. For the adapted breath-hold technique, a spirometer dedicated to DIBH radiotherapy was used. Three-dimensional conformal radiotherapy was performed with those patients. Results: Fifty patients with Hodgkin lymphoma (48 patients with primary Hodgkin lymphoma, 1 patient with recurrent disease, and 1 patient with refractory disease) entered the study from January 2003 to August 2008. Thirty-two patients were treated with IMRT, and 18 patients were treated with the DIBH technique. The median age was 28 years (range, 17-62 years). Thirty-four (68%) patients had stage I - (I-IIA) IIA disease, and 16 (32%) patients had stage I - (I-IIB) IIB disease. All but 3 patients received three to six cycles of adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD). The median radiation doses to patients treated with IMRT and DIBH were, respectively, 40 Gy (range, 21.6-40 Gy) and 30.6 Gy (range, 19.8-40 Gy). Protection of various organs at risk was satisfactory. Median follow-up was 53.4 months (range, 19.1-93 months). The 5-year progression-free and overall survival rates for the whole population were 92% (95% confidence interval [CI], 80%-97%) and 94% (95% CI, 75%-98%), respectively. Recurrences occurred in 4 patients: 2 patients had in-field relapses, and 2 patients had visceral recurrences. Grade 3 acute lung toxicity (transient pneumonitis) occurred in 1 case. Conclusions

  17. Prophylactic treatment of mycotic mucositis in radiotherapy of patients with head and neck cancers.

    PubMed

    Koc, Mehmet; Aktas, Esin

    2003-02-01

    Patients undergoing radiotherapy for head and neck cancer are at increased risk of developing oral candidiasis. The objective of this study was to investigate the clinical Candida mucositis and interruptions in radiotherapy in patients suffering from head and neck cancer, receiving fluconazole in comparison with a control group without specific prophylaxis. Eighty consecutive patients were randomized in a prospective double-blind trial of prophylactic oral fluconazole or treatment with the same drug when mycotic infections appeared. Adult head and neck cancer patients who were undergoing treatment with radiotherapy and/or chemotherapy, radiotherapeutic coverage of the entire oropharynx and oral cavity at least 3 cm anterior to the retromolar trigone and receiving a total dose of more than 6000 cGy and Karnofsky Performance Status (KPS) >70 were included in the study. Group A received radiation therapy plus fluconazole (Fluzole 100 mg/day) starting from the sixth irradiation session throughout the treatment; 40 patients in group B received the same baseline treatment, but were given fluconazole only when mycotic infections appeared. We evaluated 37 patients in group A and the first 37 patients were evaluated in group B. Three of the patients in group A (8.1%) and 14 of the patients in group B (37.8%) demonstrated clinical candidasis. Radiotherapy was interrupted in all of these patients. The differences between the two groups were statistically significant with respect to clinical candidiasis (P = 0.005). The median discontinuation time was 5 days (range, 3-7 days) in group A and 7 days (range, 4-10 days) in group B. The median dose resulting in clinical candidiasis was 3200 cGy (range, 2200-5800 cGy) in all groups. In the fluconazole group it was 4200 cGy and in the control group 2800 cGy. These results suggest that patients undergoing head and neck radiation therapy are at risk of developing candidiasis and that fluconazole may be used to reduce the frequency of

  18. Cobalt 60 radiotherapy for treatment of squamous cell carcinoma of the nasal cavity and paranasal sinuses in three horses.

    PubMed

    Walker, M A; Schumacher, J; Schmitz, D G; McMullen, W C; Ruoff, W W; Crabill, M R; Hawkins, J F; Hogan, P M; McClure, S R; Vacek, J R; Edwards, J F; Helman, R G; Frelier, P F

    1998-03-15

    Three adult horses underwent aggressive treatment of squamous cell carcinoma of the nasal cavity and paranasal sinuses, using course-fractionated cobalt 60 radiotherapy. Squamous cell carcinoma of the nasal cavity and paranasal sinuses is not commonly diagnosed in horses. Historically, horses with this type of neoplasm have not been treated or have undergone some form of surgery. The prognosis for long-term survival or cure has been poor. Long-term results of cobalt 60 radiotherapy were good to excellent and exceeded those usually reported for horses treated surgically. On the basis of these results, use of radiotherapy for these neoplasms is recommended.

  19. American Association of Physicists in Medicine Radiation Therapy Committee Task Group 53: quality assurance for clinical radiotherapy treatment planning.

    PubMed

    Fraass, B; Doppke, K; Hunt, M; Kutcher, G; Starkschall, G; Stern, R; Van Dyke, J

    1998-10-01

    In recent years, the sophistication and complexity of clinical treatment planning and treatment planning systems has increased significantly, particularly including three-dimensional (3D) treatment planning systems, and the use of conformal treatment planning and delivery techniques. This has led to the need for a comprehensive set of quality assurance (QA) guidelines that can be applied to clinical treatment planning. This document is the report of Task Group 53 of the Radiation Therapy Committee of the American Association of Physicists in Medicine. The purpose of this report is to guide and assist the clinical medical physicist in developing and implementing a comprehensive but viable program of quality assurance for modern radiotherapy treatment planning. The scope of the QA needs for treatment planning is quite broad, encompassing image-based definition of patient anatomy, 3D beam descriptions for complex beams including multileaf collimator apertures, 3D dose calculation algorithms, and complex plan evaluation tools including dose volume histograms. The Task Group recommends an organizational framework for the task of creating a QA program which is individualized to the needs of each institution and addresses the issues of acceptance testing, commissioning the planning system and planning process, routine quality assurance, and ongoing QA of the planning process. This report, while not prescribing specific QA tests, provides the framework and guidance to allow radiation oncology physicists to design comprehensive and practical treatment planning QA programs for their clinics.

  20. Forward treatment planning for modulated electron radiotherapy (MERT) employing Monte Carlo methods

    SciTech Connect

    Henzen, D. Manser, P.; Frei, D.; Volken, W.; Born, E. J.; Lössl, K.; Aebersold, D. M.; Fix, M. K.; Neuenschwander, H.; Stampanoni, M. F. M.

    2014-03-15

    Purpose: This paper describes the development of a forward planning process for modulated electron radiotherapy (MERT). The approach is based on a previously developed electron beam model used to calculate dose distributions of electron beams shaped by a photon multi leaf collimator (pMLC). Methods: As the electron beam model has already been implemented into the Swiss Monte Carlo Plan environment, the Eclipse treatment planning system (Varian Medical Systems, Palo Alto, CA) can be included in the planning process for MERT. In a first step, CT data are imported into Eclipse and a pMLC shaped electron beam is set up. This initial electron beam is then divided into segments, with the electron energy in each segment chosen according to the distal depth of the planning target volume (PTV) in beam direction. In order to improve the homogeneity of the dose distribution in the PTV, a feathering process (Gaussian edge feathering) is launched, which results in a number of feathered segments. For each of these segments a dose calculation is performed employing the in-house developed electron beam model along with the macro Monte Carlo dose calculation algorithm. Finally, an automated weight optimization of all segments is carried out and the total dose distribution is read back into Eclipse for display and evaluation. One academic and two clinical situations are investigated for possible benefits of MERT treatment compared to standard treatments performed in our clinics and treatment with a bolus electron conformal (BolusECT) method. Results: The MERT treatment plan of the academic case was superior to the standard single segment electron treatment plan in terms of organs at risk (OAR) sparing. Further, a comparison between an unfeathered and a feathered MERT plan showed better PTV coverage and homogeneity for the feathered plan, with V{sub 95%} increased from 90% to 96% and V{sub 107%} decreased from 8% to nearly 0%. For a clinical breast boost irradiation, the MERT plan

  1. Radiotherapy in the Treatment of Patients With Unresectable Extrahepatic Cholangiocarcinoma

    SciTech Connect

    Ghafoori, A. Paiman; Nelson, John W.; Willett, Christopher G.; Chino, Junzo; Tyler, Douglas S.; Hurwitz, Herbert I.; Uronis, Hope E.; Morse, Michael A.; Clough, Robert W.; Czito, Brian G.

    2011-11-01

    Purpose: Extrahepatic cholangiocarcinoma is an uncommon but lethal malignancy. We analyzed the role of definitive chemoradiotherapy for patients with nonmetastatic, locally advanced extrahepatic cholangiocarcinoma treated at a single institution. Methods and Materials: This retrospective analysis included 37 patients who underwent external beam radiation therapy (EBRT) with concurrent chemotherapy and/or brachytherapy (BT) for locally advanced extrahepatic cholangiocarcinoma. Local control (LC) and overall survival (OS) were assessed, and univariate regression analysis was used to evaluate the effects of patient- and treatment-related factors on clinical outcomes. Results: Twenty-three patients received EBRT alone, 8 patients received EBRT plus BT, and 6 patients received BT alone (median follow-up of 14 months). Two patients were alive without evidence of recurrence at the time of analysis. Actuarial OS and LC rates at 1 year were 59% and 90%, respectively, and 22% and 71%, respectively, at 2 years. Two patients lived beyond 5 years without evidence of recurrence. On univariate analysis, EBRT with or without BT improved LC compared to BT alone (97% vs. 56% at 1 year; 75% vs. 56% at 2 years; p = 0.096). Patients who received EBRT alone vs. BT alone also had improved LC (96% vs. 56% at 1 year; 80% vs. 56% at 2 years; p = 0.113). Age, gender, tumor location (proximal vs. distal), histologic differentiation, EBRT dose ({<=} or >50 Gy), EBRT planning method (two-dimensional vs. three-dimensional), and chemotherapy were not associated with patient outcomes. Conclusions: Patients with locally advanced extrahepatic cholangiocarcinoma have poor survival. Long-term survival is rare. The majority of patients treated with EBRT had local control at the time of death, suggesting that symptoms due to the local tumor effect might be effectively controlled with radiation therapy, and EBRT is an important element of treatment. Novel treatment approaches are indicated in the therapy

  2. RADIOTHERAPY IN THE TREATMENT OF PATIENTS WITH UNRESECTABLE EXTRAHEPATIC CHOLANGIOCARCINOMA

    PubMed Central

    Ghafoori, A. Paiman; Nelson, John W.; Willett, Christopher G.; Chino, Junzo; Tyler, Douglas S.; Hurwitz, Herbert I.; Uronis, Hope E.; Morse, Michael A.; Clough, Robert W.; Czito, Brian G.

    2014-01-01

    Purpose Extrahepatic cholangiocarcinoma is an uncommon but lethal malignancy. We analyzed the role of definitive chemoradiotherapy for patients with nonmetastatic, locally advanced extrahepatic cholangiocarcinoma treated at a single institution. Methods and Materials This retrospective analysis included 37 patients who underwent external beam radiation therapy (EBRT) with concurrent chemotherapy and/or brachytherapy (BT) for locally advanced extrahepatic cholangiocarcinoma. Local control (LC) and overall survival (OS) were assessed, and univariate regression analysis was used to evaluate the effects of patient- and treatment-related factors on clinical outcomes. Results Twenty-three patients received EBRT alone, 8 patients received EBRT plus BT, and 6 patients received BT alone (median follow-up of 14 months). Two patients were alive without evidence of recurrence at the time of analysis. Actuarial OS and LC rates at 1 year were 59% and 90%, respectively, and 22% and 71%, respectively, at 2 years. Two patients lived beyond 5 years without evidence of recurrence. On univariate analysis, EBRT with or without BT improved LC compared to BT alone (97% vs. 56% at 1 year; 75% vs. 56% at 2 years; p = 0.096). Patients who received EBRT alone vs. BT alone also had improved LC (96% vs. 56% at 1 year; 80% vs. 56% at 2 years; p = 0.113). Age, gender, tumor location (proximal vs. distal), histologic differentiation, EBRT dose (≤ or >50 Gy), EBRT planning method (two-dimensional vs. three-dimensional), and chemotherapy were not associated with patient outcomes. Conclusions Patients with locally advanced extrahepatic cholangiocarcinoma have poor survival. Long-term survival is rare. The majority of patients treated with EBRT had local control at the time of death, suggesting that symptoms due to the local tumor effect might be effectively controlled with radiation therapy, and EBRT is an important element of treatment. Novel treatment approaches are indicated in the therapy for

  3. Voxel-based dose prediction with multi-patient atlas selection for automated radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    McIntosh, Chris; Purdie, Thomas G.

    2017-01-01

    Automating the radiotherapy treatment planning process is a technically challenging problem. The majority of automated approaches have focused on customizing and inferring dose volume objectives to be used in plan optimization. In this work we outline a multi-patient atlas-based dose prediction approach that learns to predict the dose-per-voxel for a novel patient directly from the computed tomography planning scan without the requirement of specifying any objectives. Our method learns to automatically select the most effective atlases for a novel patient, and then map the dose from those atlases onto the novel patient. We extend our previous work to include a conditional random field for the optimization of a joint distribution prior that matches the complementary goals of an accurately spatially distributed dose distribution while still adhering to the desired dose volume histograms. The resulting distribution can then be used for inverse-planning with a new spatial dose objective, or to create typical dose volume objectives for the canonical optimization pipeline. We investigated six treatment sites (633 patients for training and 113 patients for testing) and evaluated the mean absolute difference in all DVHs for the clinical and predicted dose distribution. The results on average are favorable in comparison to our previous approach (1.91 versus 2.57). Comparing our method with and without atlas-selection further validates that atlas-selection improved dose prediction on average in whole breast (0.64 versus 1.59), prostate (2.13 versus 4.07), and rectum (1.46 versus 3.29) while it is less important in breast cavity (0.79 versus 0.92) and lung (1.33 versus 1.27) for which there is high conformity and minimal dose shaping. In CNS brain, atlas-selection has the potential to be impactful (3.65 versus 5.09), but selecting the ideal atlas is the most challenging.

  4. Radiation-induced bowel injury: the impact of radiotherapy on survivorship after treatment for gynaecological cancers

    PubMed Central

    Kuku, S; Fragkos, C; McCormack, M; Forbes, A

    2013-01-01

    Background: The number of women surviving cancer who live with symptoms of bowel toxicity affecting their quality of life continues to rise. In this retrospective study, we sought to describe and analyse the presenting clinical features in our cohort, and evaluate possible predictors of severity and chronicity in women with radiation-induced bowel injury after treatment for cervical and endometrial cancers. Methods: Review of records of 541 women treated within the North London Gynaecological Cancer Network between 2003 and 2010 with radiotherapy with or without chemotherapy for cervical and endometrial cancer identified 152 women who reported significant new bowel symptoms after pelvic radiation. Results: Factor analysis showed that the 14 most common and important presenting symptoms could be ‘clustered' into 3 groups with predictive significance for chronicity and severity of disease. Median follow-up for all patients was 60 months. Univariate analysis showed increasing age, smoking, extended field radiation, cervical cancer treatment and the need for surgical intervention to be significant predictors for severity of ongoing disease at last follow-up. On multivariate analysis, only age, cancer type (cervix) and symptom combinations/‘cluster' of (bloating, flatulence, urgency, rectal bleeding and per-rectal mucus) were found to be significant predictors of disease severity. Fifteen (19%) women in the cervical cancer group had radiation-induced bowel injury requiring surgical intervention compared with five (6.7%) in the endometrial cancer group. Conclusion: Women with cervical cancer are younger and appear to suffer more severe symptoms of late bowel toxicity, whereas women treated for endometrial cancer suffer milder more chronic disease. The impact of radiation-induced bowel injury and the effect on cancer survivorship warrants further research into investigation of predictors of severe late toxicity. There is a need for prospective trials to aid early

  5. Effect of self-selected music on adults' anxiety and subjective experiences during initial radiotherapy treatment: a randomised controlled trial and qualitative research.

    PubMed

    O'Callaghan, Clare; Sproston, Michael; Wilkinson, Kate; Willis, David; Milner, Alvin; Grocke, Denise; Wheeler, Greg

    2012-08-01

    Patients may experience radiotherapy as anxiety provoking, especially during unfamiliar initial treatment. This study examines whether patients' use of self-selected music while undergoing first radiotherapy treatment reduces anxiety, and how patients describe their first radiotherapy experience with or without self-selected music. Using quantitative and qualitative methods, 100 participants preparing to commence radiotherapy were assigned to the initial radiotherapy session either with self-selected music or without music. In both participant groups, the Spielberger State Anxiety Inventory measured pre- and post-radiotherapy levels, music preference questions examined future music desires during treatment and a semistructured questionnaire examined additional subjective experiences. Overall, participants were not highly anxious pre-radiotherapy, anxiety decreased in both music and control groups following radiotherapy (P = 0.008) and this change was not different between groups (P = 0.35). However, music group participants were significantly more likely to want music in future radiotherapy sessions (P = 0.007). Some reported a benefit from the music in terms of feeling supported, distracted or that treatment time seemed faster. Participants in both groups often commended helpful staff. Negative reactions were only occasional. Although preferred music does not reduce anxiety, it can support some patients undergoing initial radiotherapy and departmental staff should invite patients to bring music to radiotherapy, provide music libraries and offer to play patient selected music during treatments. © 2012 The Authors. Journal of Medical Imaging and Radiation Oncology © 2012 The Royal Australian and New Zealand College of Radiologists.

  6. A comparison between anisotropic analytical and multigrid superposition dose calculation algorithms in radiotherapy treatment planning

    SciTech Connect

    Wu, Vincent W.C.; Tse, Teddy K.H.; Ho, Cola L.M.; Yeung, Eric C.Y.

    2013-07-01

    Monte Carlo (MC) simulation is currently the most accurate dose calculation algorithm in radiotherapy planning but requires relatively long processing time. Faster model-based algorithms such as the anisotropic analytical algorithm (AAA) by the Eclipse treatment planning system and multigrid superposition (MGS) by the XiO treatment planning system are 2 commonly used algorithms. This study compared AAA and MGS against MC, as the gold standard, on brain, nasopharynx, lung, and prostate cancer patients. Computed tomography of 6 patients of each cancer type was used. The same hypothetical treatment plan using the same machine and treatment prescription was computed for each case by each planning system using their respective dose calculation algorithm. The doses at reference points including (1) soft tissues only, (2) bones only, (3) air cavities only, (4) soft tissue-bone boundary (Soft/Bone), (5) soft tissue-air boundary (Soft/Air), and (6) bone-air boundary (Bone/Air), were measured and compared using the mean absolute percentage error (MAPE), which was a function of the percentage dose deviations from MC. Besides, the computation time of each treatment plan was recorded and compared. The MAPEs of MGS were significantly lower than AAA in all types of cancers (p<0.001). With regards to body density combinations, the MAPE of AAA ranged from 1.8% (soft tissue) to 4.9% (Bone/Air), whereas that of MGS from 1.6% (air cavities) to 2.9% (Soft/Bone). The MAPEs of MGS (2.6%±2.1) were significantly lower than that of AAA (3.7%±2.5) in all tissue density combinations (p<0.001). The mean computation time of AAA for all treatment plans was significantly lower than that of the MGS (p<0.001). Both AAA and MGS algorithms demonstrated dose deviations of less than 4.0% in most clinical cases and their performance was better in homogeneous tissues than at tissue boundaries. In general, MGS demonstrated relatively smaller dose deviations than AAA but required longer computation time.

  7. Physical aspects of external beam radiotherapy for the treatment of malignant pleural mesothelioma

    SciTech Connect

    Soubra, M.; Dunscombe, P.B.; Hodson, D.I.; Wong, G. )

    1990-06-01

    The optimization of radiotherapy for the treatment of malignant mesothelioma highlights many of the currently outstanding problems in clinical radiation physics. The experimental investigation of an intuitively attractive irradiation technique with combined photon and electron beams using a specially constructed phantom has established that, due to the penetration in low density material of both primary electrons and those secondary to photon irradiation, the normal lung tissue is not spared to any significant degree by such a technique. Furthermore, great care needs to be exercised in the treatment planning calculations for this approach if absolute dosimetry errors as large as 50% are to be avoided.

  8. Monte Carlo treatment planning for molecular targeted radiotherapy within the MINERVA system

    NASA Astrophysics Data System (ADS)

    Lehmann, Joerg; Hartmann Siantar, Christine; Wessol, Daniel E.; Wemple, Charles A.; Nigg, David; Cogliati, Josh; Daly, Tom; Descalle, Marie-Anne; Flickinger, Terry; Pletcher, David; DeNardo, Gerald

    2005-03-01

    The aim of this project is to extend accurate and patient-specific treatment planning to new treatment modalities, such as molecular targeted radiation therapy, incorporating previously crafted and proven Monte Carlo and deterministic computation methods. A flexible software environment is being created that allows planning radiation treatment for these new modalities and combining different forms of radiation treatment with consideration of biological effects. The system uses common input interfaces, medical image sets for definition of patient geometry and dose reporting protocols. Previously, the Idaho National Engineering and Environmental Laboratory (INEEL), Montana State University (MSU) and Lawrence Livermore National Laboratory (LLNL) had accrued experience in the development and application of Monte Carlo based, three-dimensional, computational dosimetry and treatment planning tools for radiotherapy in several specialized areas. In particular, INEEL and MSU have developed computational dosimetry systems for neutron radiotherapy and neutron capture therapy, while LLNL has developed the PEREGRINE computational system for external beam photon-electron therapy. Building on that experience, the INEEL and MSU are developing the MINERVA (modality inclusive environment for radiotherapeutic variable analysis) software system as a general framework for computational dosimetry and treatment planning for a variety of emerging forms of radiotherapy. In collaboration with this development, LLNL has extended its PEREGRINE code to accommodate internal sources for molecular targeted radiotherapy (MTR), and has interfaced it with the plugin architecture of MINERVA. Results from the extended PEREGRINE code have been compared to published data from other codes, and found to be in general agreement (EGS4—2%, MCNP—10%) (Descalle et al 2003 Cancer Biother. Radiopharm. 18 71-9). The code is currently being benchmarked against experimental data. The interpatient variability of

  9. Monte Carlo Treatment Planning for Molecular Targeted Radiotherapy within the MINERVA System

    SciTech Connect

    Lehmann, J; Siantar, C H; Wessol, D E; Wemple, C A; Nigg, D; Cogliati, J; Daly, T; Descalle, M; Flickinger, T; Pletcher, D; DeNardo, G

    2004-09-22

    The aim of this project is to extend accurate and patient-specific treatment planning to new treatment modalities, such as molecular targeted radiation therapy, incorporating previously crafted and proven Monte Carlo and deterministic computation methods. A flexible software environment is being created that allows planning radiation treatment for these new modalities and combining different forms of radiation treatment with consideration of biological effects. The system uses common input interfaces, medical image sets for definition of patient geometry, and dose reporting protocols. Previously, the Idaho National Engineering and Environmental Laboratory (INEEL), Montana State University (MSU), and Lawrence Livermore National Laboratory (LLNL) had accrued experience in the development and application of Monte Carlo-based, three-dimensional, computational dosimetry and treatment planning tools for radiotherapy in several specialized areas. In particular, INEEL and MSU have developed computational dosimetry systems for neutron radiotherapy and neutron capture therapy, while LLNL has developed the PEREGRINE computational system for external beam photon-electron therapy. Building on that experience, the INEEL and MSU are developing the MINERVA (Modality Inclusive Environment for Radiotherapeutic Variable Analysis) software system as a general framework for computational dosimetry and treatment planning for a variety of emerging forms of radiotherapy. In collaboration with this development, LLNL has extended its PEREGRINE code to accommodate internal sources for molecular targeted radiotherapy (MTR), and has interfaced it with the plug-in architecture of MINERVA. Results from the extended PEREGRINE code have been compared to published data from other codes, and found to be in general agreement (EGS4 - 2%, MCNP - 10%)(Descalle et al. 2003). The code is currently being benchmarked against experimental data. The interpatient variability of the drug pharmacokinetics in MTR

  10. Advanced chemoresistant breast cancer responding to multidisciplinary treatment with hyperthermia, radiotherapy, and intraarterial infusion.

    PubMed

    Yokoyama, Goro; Fujii, Teruhiko; Ogo, Etsuyo; Yanaga, Hiroshi; Toh, Uhi; Yamaguchi, Miki; Mishima, Mai; Takamori, Shinzo; Shirouzu, Kazuo; Yamana, Hideaki

    2005-04-01

    We employed multidisciplinary therapy, consisting of hyperthermia, radiotherapy, and intraarterial infusion, for a patient with progressive advanced breast cancer that was resistant to epirubicin hydrochloride and cyclophosphamide (EC) therapy as well as being resistant to docetaxel hydrate, and obtained a good therapeutic response. Because estrogen and progesterone receptors were both negative and HER2 was 3(+), administration of trastuzumab was started, and this patient has shown no signs of recurrence at 33 months after our treatment. The results suggested that our multidisciplinary therapy can be an effective method for the treatment of progressive breast cancer showing resistance to major chemotherapy agents such as anthracyclines and taxanes.

  11. Monte Carlo treatment planning for molecular targeted radiotherapy within the MINERVA system.

    PubMed

    Lehmann, Joerg; Hartmann Siantar, Christine; Wessol, Daniel E; Wemple, Charles A; Nigg, David; Cogliati, Josh; Daly, Tom; Descalle, Marie-Anne; Flickinger, Terry; Pletcher, David; Denardo, Gerald

    2005-03-07

    The aim of this project is to extend accurate and patient-specific treatment planning to new treatment modalities, such as molecular targeted radiation therapy, incorporating previously crafted and proven Monte Carlo and deterministic computation methods. A flexible software environment is being created that allows planning radiation treatment for these new modalities and combining different forms of radiation treatment with consideration of biological effects. The system uses common input interfaces, medical image sets for definition of patient geometry and dose reporting protocols. Previously, the Idaho National Engineering and Environmental Laboratory (INEEL), Montana State University (MSU) and Lawrence Livermore National Laboratory (LLNL) had accrued experience in the development and application of Monte Carlo based, three-dimensional, computational dosimetry and treatment planning tools for radiotherapy in several specialized areas. In particular, INEEL and MSU have developed computational dosimetry systems for neutron radiotherapy and neutron capture therapy, while LLNL has developed the PEREGRINE computational system for external beam photon-electron therapy. Building on that experience, the INEEL and MSU are developing the MINERVA (modality inclusive environment for radiotherapeutic variable analysis) software system as a general framework for computational dosimetry and treatment planning for a variety of emerging forms of radiotherapy. In collaboration with this development, LLNL has extended its PEREGRINE code to accommodate internal sources for molecular targeted radiotherapy (MTR), and has interfaced it with the plugin architecture of MINERVA. Results from the extended PEREGRINE code have been compared to published data from other codes, and found to be in general agreement (EGS4-2%, MCNP-10%) (Descalle et al 2003 Cancer Biother. Radiopharm. 18 71-9). The code is currently being benchmarked against experimental data. The interpatient variability of the

  12. Development of an ATM-based radiology consultation workstation for radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Kempner, Kenneth M.; Chow, David; Choyke, Peter L.; Cox, Jerome R., Jr.; Elson, Jeremy E.; Johnson, Calvin A.; Okunieff, Paul; Ostrow, Harold; Pfeifer, John C.; Martino, Robert L.

    1997-05-01

    The radiology consultation workstation is a multimedia, medical imaging workstation being developed for use in an electronic radiology environment, utilizing a prototype asynchronous transfer mode telemedicine network, in support of radiotherapy treatment planning. A radiation oncologist in the radiation oncology department, and a radiologist in the Diagnostic Radiology Department, will be able to consult, utilizing high-quality audio/video channels and high-resolution medical image displays, prior to the design of a treatment plan. Organ and lesion contouring is performed via a shared-cursor feature, in a consultation mode, allowing medical specialists to fully interact during the identification and delineation of lesions and other features.

  13. Prophylaxis versus treatment: Is there a better way to manage radiotherapy-induced nausea and vomiting?

    SciTech Connect

    Horiot, Jean-Claude . E-mail: horiotjc@dijon.fnclcc.fr

    2004-11-15

    Nausea and vomiting are two of the most distressing side effects of radiotherapy and cytotoxic drugs, which currently are often combined to treat moderately advanced and advanced solid tumors. Inadequate control of these symptoms may result in significant patient suffering and decrease in the patient's quality of life, which has been shown to decrease patients' compliance to treatment, with potential impact on disease outcome. It is, therefore, important that radiation oncologists recognize the need for adequate prophylactic treatment of radiation-induced nausea and vomiting (RINV) to avoid the detrimental effects on patients' quality of life, and optimize chances for cure. The 5-hydroxytryptamine type 3 (5-HT{sub 3})-receptor antagonists have been proved to provide effective antiemetic therapy in patients undergoing highly emetogenic radiotherapy. Nevertheless, several large surveys have shown that optimal treatments are not always used. Hence, a risk exists that waiting for RINV symptoms rather than prescribing prophylactic antiemetic treatment may lead to increased patient suffering, poorer disease control, and less cost-effective therapy options. Prophylactic management with an effective 5-HT{sub 3}-receptor antagonist should offer a better treatment option for patients at high to moderate risk of RINV. Adequate control of RINV should contribute to patient compliance to treatment, improved therapy outcomes, and decreased burdens on nursing and health care resources.

  14. [Radiotherapy of bone metastases].

    PubMed

    Thureau, S; Vieillard, M-H; Supiot, S; Lagrange, J-L

    2016-09-01

    Radiotherapy plays a major role in palliative treatment of bone metastases. Recent developments of stereotactic radiotherapy and intensity modulated radiation therapy give the possibility to treat oligometastatic diseases. The objective of this paper is to report indications and treatment modalities of radiotherapy in these situations.

  15. AutoLock: a semiautomated system for radiotherapy treatment plan quality control.

    PubMed

    Dewhurst, Joseph M; Lowe, Matthew; Hardy, Mark J; Boylan, Christopher J; Whitehurst, Philip; Rowbottom, Carl G

    2015-05-08

    A semiautomated system for radiotherapy treatment plan quality control (QC), named AutoLock, is presented. AutoLock is designed to augment treatment plan QC by automatically checking aspects of treatment plans that are well suited to computational evaluation, whilst summarizing more subjective aspects in the form of a checklist. The treatment plan must pass all automated checks and all checklist items must be acknowledged by the planner as correct before the plan is finalized. Thus AutoLock uniquely integrates automated treatment plan QC, an electronic checklist, and plan finalization. In addition to reducing the potential for the propagation of errors, the integration of AutoLock into the plan finalization workflow has improved efficiency at our center. Detailed audit data are presented, demonstrating that the treatment plan QC rejection rate fell by around a third following the clinical introduction of AutoLock.

  16. Modified radiotherapy technique in the treatment of medulloblastoma

    SciTech Connect

    Dewit, L.; Van Dam, J.; Rijnders, A.; Van De Velde, G.; Ang, K.K.; Van Der Schueren, E.

    1984-02-01

    Craniospinal irradiation is a standard treatment technique in patients who receive surgery for medulloblastoma. In most centers megavoltage photon irradiation is used, resulting in significant irradiation exposure to critical organs. In order to overcome this difficulty, the authors recently modified the technique applied in their center, by using high energy electrons (20 MeV) for irradiation of the spinal cord. The reliability of this technique was checked by performing dosimetry in a specially constructed wax phantom. Attention was focused upon dose variations at the junction of fields. Furthermore, the influence of vertebrae on the absorbed dose distribution of high energy electrons is presented. This technique seems to be safe and reliable in selected patients (children and teenagers).

  17. Postoperative Irradiation of Gynecologic Malignancies: Improving Treatment Delivery Using Aperture-Based Intensity-Modulated Radiotherapy

    SciTech Connect

    Nadeau, Sylvain . E-mail: sylvainn@rrsb.nb.ca; Bouchard, Myriam; Germain, Isabelle; Raymond, Paul-Emile; Beaulieu, Frederic; Beaulieu, Luc; Roy, Rene; Gingras, Luc

    2007-06-01

    Purpose: To evaluate dosimetric and treatment delivery advantages of aperture-based intensity-modulated radiotherapy (AB-IMRT) for the treatment of patients receiving whole pelvic radiotherapy for gynecologic malignancies. Methods and Materials: Nineteen patients undergoing pelvic radiotherapy after resection of endometrial cancers were selected. A 45-Gy dose was prescribed to the target volume delineated on a planning CT scan. An in-house inverse planning system, Ballista, was used to develop a treatment plan using aperture-based multileaf collimator segments. This approach was compared with conventional four-field, enlarged four-field, and static beamlet-based IMRT (BB-IMRT) techniques in terms of target coverage, dose-volume histogram statistics for surrounding normal tissues, and numbers of segments and monitor units (MU). Results: Three quarters (76.4%) of the planning target volume received the prescription dose with conventional four-field plans. With adequate target coverage, the Ballista plans significantly reduced the volume of bowel and bladder irradiated at the prescribed dose (p < 0.001), whereas the two approaches provided equivalent results for the rectum (p 0.5). On the other hand, AB-IMRT and BB-IMRT plans showed only small differences in dose-volume histogram statistics of unknown clinical impact, whereas Ballista plan delivery required on average 73% and 59% fewer segments and MU, respectively. Conclusion: With respect to conventional techniques, AB-IMRT for the treatment of gynecologic malignancies provides dosimetric advantages similar to those with BB-IMRT but with clear treatment delivery improvements.

  18. Tally and geometry definition influence on the computing time in radiotherapy treatment planning with MCNP Monte Carlo code.

    PubMed

    Juste, B; Miro, R; Gallardo, S; Santos, A; Verdu, G

    2006-01-01

    The present work has simulated the photon and electron transport in a Theratron 780 (MDS Nordion) (60)Co radiotherapy unit, using the Monte Carlo transport code, MCNP (Monte Carlo N-Particle), version 5. In order to become computationally more efficient in view of taking part in the practical field of radiotherapy treatment planning, this work is focused mainly on the analysis of dose results and on the required computing time of different tallies applied in the model to speed up calculations.

  19. Should adjuvant radiotherapy to the supraclavicular fossa be routinely given in patients with breast conservative treatment?

    PubMed

    Wang, Chun-Wei; Kuo, Wen-Hong; Chang, King-Jen; Huang, Chiun-Sheng; Cheng, Jason Chia-Hsien

    2007-08-01

    To analyze the overall outcome, supraclavicular fossa (SCF) recurrence rate, and pattern of failure in breast cancer patients treated with conservative surgery and adjuvant radiotherapy excluding SCF treatment. A total of 143 patients were enrolled in the study. Ninety-two percent of patients were stages I and II, and 8% were stage III. The median age was 44 years, and 31% of patients were Radiotherapy was delivered to the ipsilateral breast excluding the SCF. The 5-year overall survival rate of the cohort was 95%, and disease-free survival rate was 91%. The cumulative incidence of SCF recurrence was 18% in patients with involved axillary nodes (N) >/= 4, and 0.8% in patients with N < 4. The 5-year SCF-recurrence-free survival in patients with N >/= 4 and N < 4 was 80% and 99%, respectively (P < 0.001). N >/= 4 was the only independent predictor for locoregional control (P = 0.045), disease-free survival (P = 0.001), and overall survival (P = 0.008) in multivariate analysis. Women with N >/= 4 have a significantly higher risk of SCF recurrence and poorer survival. The SCF might be safely spared in patients with N < 4, but should be routinely included in the radiotherapy design for those with N >/= 4.

  20. Combination ibandronate and radiotherapy for the treatment of bone metastases: Clinical evaluation and radiologic assessment

    SciTech Connect

    Vassiliou, Vassilios; Kalogeropoulou, Christine; Christopoulos, Christos; Solomou, Ekaterini; Leotsinides, Michael; Kardamakis, Dimitrios . E-mail: kardim@med.upatras.gr

    2007-01-01

    Purpose: Ibandronate is a single-nitrogen, noncyclic bisphosphonate with proven efficacy for reducing metastatic bone pain. In this study, we assessed the palliative effects of combined ibandronate and radiotherapy. Methods and Materials: Forty-five patients with bone metastases from various solid tumors received external-beam radiotherapy, 30-40 Gy over 3-4.5, weeks combined with 10 cycles of monthly intravenous ibandronate, 6 mg. Results: After combined therapy, mean bone pain scores (graded from 0 to 10) were reduced from 6.3 at baseline to 0.8 after 3 months, with further reductions at later time points (all p < 0.001). Opioid use decreased from 84% of patients at baseline (38/45) to 24% (11/45) at 3 months, with further subsequent reductions (all p < 0.001). Mean performance status and functioning scores also significantly improved. Bone density (assessed by computed tomography scan) increased by 20% vs. baseline at 3 months, 46% at 6 months, and 73% at 10 months (all p < 0.001). Lesion improvement was also demonstrated by magnetic resonance imaging. Treatment was well tolerated with no renal toxicity. Conclusions: In this pilot study, combined radiotherapy and ibandronate provided substantial bone pain relief and increased bone density. Computed tomography-based or magnetic resonance imaging-based evaluations offer objective methods for assessing therapeutic outcomes.

  1. A feasibility study of treatment verification using EPID cine images for hypofractionated lung radiotherapy

    NASA Astrophysics Data System (ADS)

    Tang, Xiaoli; Lin, Tong; Jiang, Steve

    2009-09-01

    We propose a novel approach for potential online treatment verification using cine EPID (electronic portal imaging device) images for hypofractionated lung radiotherapy based on a machine learning algorithm. Hypofractionated radiotherapy requires high precision. It is essential to effectively monitor the target to ensure that the tumor is within the beam aperture. We modeled the treatment verification problem as a two-class classification problem and applied an artificial neural network (ANN) to classify the cine EPID images acquired during the treatment into corresponding classes—with the tumor inside or outside of the beam aperture. Training samples were generated for the ANN using digitally reconstructed radiographs (DRRs) with artificially added shifts in the tumor location—to simulate cine EPID images with different tumor locations. Principal component analysis (PCA) was used to reduce the dimensionality of the training samples and cine EPID images acquired during the treatment. The proposed treatment verification algorithm was tested on five hypofractionated lung patients in a retrospective fashion. On average, our proposed algorithm achieved a 98.0% classification accuracy, a 97.6% recall rate and a 99.7% precision rate. This work was first presented at the Seventh International Conference on Machine Learning and Applications, San Diego, CA, USA, 11-13 December 2008.

  2. The first patient treatment of electromagnetic-guided real time adaptive radiotherapy using MLC tracking for lung SABR.

    PubMed

    Booth, Jeremy T; Caillet, Vincent; Hardcastle, Nicholas; O'Brien, Ricky; Szymura, Kathryn; Crasta, Charlene; Harris, Benjamin; Haddad, Carol; Eade, Thomas; Keall, Paul J

    2016-10-01

    Real time adaptive radiotherapy that enables smaller irradiated volumes may reduce pulmonary toxicity. We report on the first patient treatment of electromagnetic-guided real time adaptive radiotherapy delivered with MLC tracking for lung stereotactic ablative body radiotherapy. A clinical trial was developed to investigate the safety and feasibility of MLC tracking in lung. The first patient was an 80-year old man with a single left lower lobe lung metastasis to be treated with SABR to 48Gy in 4 fractions. In-house software was integrated with a standard linear accelerator to adapt the treatment beam shape and position based on electromagnetic transponders implanted in the lung. MLC tracking plans were compared against standard ITV-based treatment planning. MLC tracking plan delivery was reconstructed in the patient to confirm safe delivery. Real time adaptive radiotherapy delivered with MLC tracking compared to standard ITV-based planning reduced the PTV by 41% (18.7-11cm(3)) and the mean lung dose by 30% (202-140cGy), V20 by 35% (2.6-1.5%) and V5 by 9% (8.9-8%). An emerging technology, MLC tracking, has been translated into the clinic and used to treat lung SABR patients for the first time. This milestone represents an important first step for clinical real-time adaptive radiotherapy that could reduce pulmonary toxicity in lung radiotherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Radiotherapy. The mainstay in the treatment of early glottic carcinoma

    SciTech Connect

    Pellitteri, P.K.; Kennedy, T.L.; Vrabec, D.P.; Beiler, D.; Hellstrom, M. )

    1991-03-01

    Early squamous cell carcinoma of the glottis may be effectively treated with surgery or radiation therapy. Controversy exists as to whether radiation therapy effects survival at the expense of vocal function by ultimately requiring more total laryngectomies for salvage of local tumor recurrence. This study reviewed the medical records of 185 patients with T1 or T2, NO invasive squamous cell carcinoma of the glottis treated with primary radiation therapy between 1969 and 1984. All patients were followed up for a minimum of 5 years after completion of therapy. One hundred sixty-one patients met the criteria for local control analysis. Radiation therapy controlled disease in 93% (105 of 113) of patients with T1 lesions and 73% (38 of 48) of those with T2 tumors. Ultimate control of disease for T1 and T2 lesions, including surgical salvage, was 111 (98%) of 113 and 44 (92%) of 48 patients, respectively. The rate of successful surgical salvage was 75% (T1) and 70% (T2). The T2 lesions with impaired vocal cord mobility or anterior commissure disease were identified as being at increased risk for recurrence after primary radiation therapy. Overall voice preservation was 90%. Our data demonstrate that radiation therapy effects disease-free survival rates that are comparable to those produced by surgery, without sacrificing voice. Although a small percentage of patients with selected early glottic lesions may be more effectively treated with primary conservation surgery, these data do not support a change in philosophy concerning primary treatment of early glottic cancer with radiation therapy.

  4. An integrated Monte Carlo dosimetric verification system for radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Yamamoto, T.; Mizowaki, T.; Miyabe, Y.; Takegawa, H.; Narita, Y.; Yano, S.; Nagata, Y.; Teshima, T.; Hiraoka, M.

    2007-04-01

    An integrated Monte Carlo (MC) dose calculation system, MCRTV (Monte Carlo for radiotherapy treatment plan verification), has been developed for clinical treatment plan verification, especially for routine quality assurance (QA) of intensity-modulated radiotherapy (IMRT) plans. The MCRTV system consists of the EGS4/PRESTA MC codes originally written for particle transport through the accelerator, the multileaf collimator (MLC), and the patient/phantom, which run on a 28-CPU Linux cluster, and the associated software developed for the clinical implementation. MCRTV has an interface with a commercial treatment planning system (TPS) (Eclipse, Varian Medical Systems, Palo Alto, CA, USA) and reads the information needed for MC computation transferred in DICOM-RT format. The key features of MCRTV have been presented in detail in this paper. The phase-space data of our 15 MV photon beam from a Varian Clinac 2300C/D have been developed and several benchmarks have been performed under homogeneous and several inhomogeneous conditions (including water, aluminium, lung and bone media). The MC results agreed with the ionization chamber measurements to within 1% and 2% for homogeneous and inhomogeneous conditions, respectively. The MC calculation for a clinical prostate IMRT treatment plan validated the implementation of the beams and the patient/phantom configuration in MCRTV.

  5. Low-Dose-Rate Californium-252 Neutron Intracavitary Afterloading Radiotherapy Combined With Conformal Radiotherapy for Treatment of Cervical Cancer

    SciTech Connect

    Zhang Min; Xu Hongde; Pan Songdan; Lin Shan; Yue Jianhua; Liu Jianren

    2012-07-01

    Purpose: To study the efficacy of low-dose-rate californium-252 ({sup 252}Cf) neutron intracavitary afterloading radiotherapy (RT) combined with external pelvic RT for treatment of cervical cancer. Methods and Materials: The records of 96 patients treated for cervical cancer from 2006 to 2010 were retrospectively reviewed. For patients with tumors {<=}4 cm in diameter, external beam radiation was performed (1.8 Gy/day, five times/week) until the dose reached 20 Gy, and then {sup 252}Cf neutron intracavitary afterloading RT (once/week) was begun, and the frequency of external beam radiation was changed to four times/week. For patients with tumors >4 cm, {sup 252}Cf RT was performed one to two times before whole-pelvis external beam radiation. The tumor-eliminating dose was determined by using the depth limit of 5 mm below the mucosa as the reference point. In all patients, the total dose of the external beam radiation ranged from 46.8 to 50 Gy. For {sup 252}Cf RT, the dose delivered to point A was 6 Gy/fraction, once per week, for a total of seven times, and the total dose was 42 Gy. Results: The mean {+-} SD patient age was 54.7 {+-} 13.7 years. Six patients had disease assessed at stage IB, 13 patients had stage IIA, 49 patients had stage IIB, 3 patients had stage IIIA, 24 patients had stage IIIB, and 1 patient had stage IVA. All patients obtained complete tumor regression (CR). The mean {+-} SD time to CR was 23.5 {+-} 3.4 days. Vaginal bleeding was fully controlled in 80 patients within 1 to 8 days. The mean {+-} SD follow-up period was 27.6 {+-} 12.7 months (range, 6-48 months). Five patients died due to recurrence or metastasis. The 3-year survival and disease-free recurrence rates were 89.6% and 87.5 %, respectively. Nine patients experienced mild radiation proctitis, and 4 patients developed radiocystitis. Conclusions: Low-dose-rate {sup 252}Cf neutron RT combined with external pelvic RT is effective for treating cervical cancer, with a low incidence of

  6. Low-dose-rate californium-252 neutron intracavitary afterloading radiotherapy combined with conformal radiotherapy for treatment of cervical cancer.

    PubMed

    Zhang, Min; Xu, Hong-De; Pan, Song-Dan; Lin, Shan; Yue, Jian-Hua; Liu, Jian-Ren

    2012-07-01

    To study the efficacy of low-dose-rate californium-252 ((252)Cf) neutron intracavitary afterloading radiotherapy (RT) combined with external pelvic RT for treatment of cervical cancer. The records of 96 patients treated for cervical cancer from 2006 to 2010 were retrospectively reviewed. For patients with tumors ≤4 cm in diameter, external beam radiation was performed (1.8 Gy/day, five times/week) until the dose reached 20 Gy, and then (252)Cf neutron intracavitary afterloading RT (once/week) was begun, and the frequency of external beam radiation was changed to four times/week. For patients with tumors >4 cm, (252)Cf RT was performed one to two times before whole-pelvis external beam radiation. The tumor-eliminating dose was determined by using the depth limit of 5 mm below the mucosa as the reference point. In all patients, the total dose of the external beam radiation ranged from 46.8 to 50 Gy. For (252)Cf RT, the dose delivered to point A was 6 Gy/fraction, once per week, for a total of seven times, and the total dose was 42 Gy. The mean ± SD patient age was 54.7 ± 13.7 years. Six patients had disease assessed at stage IB, 13 patients had stage IIA, 49 patients had stage IIB, 3 patients had stage IIIA, 24 patients had stage IIIB, and 1 patient had stage IVA. All patients obtained complete tumor regression (CR). The mean ± SD time to CR was 23.5 ± 3.4 days. Vaginal bleeding was fully controlled in 80 patients within 1 to 8 days. The mean ± SD follow-up period was 27.6 ± 12.7 months (range, 6-48 months). Five patients died due to recurrence or metastasis. The 3-year survival and disease-free recurrence rates were 89.6% and 87.5 %, respectively. Nine patients experienced mild radiation proctitis, and 4 patients developed radiocystitis. Low-dose-rate (252)Cf neutron RT combined with external pelvic RT is effective for treating cervical cancer, with a low incidence of complications. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Diffusion tensor imaging: possible implications for radiotherapy treatment planning of patients with high-grade glioma.

    PubMed

    Jena, R; Price, S J; Baker, C; Jefferies, S J; Pickard, J D; Gillard, J H; Burnet, N G

    2005-12-01

    Radiotherapy treatment planning for high-grade gliomas (HGG) is hampered by the inability to image peri-tumoural white-matter infiltration. Diffusion tensor imaging (DTI) is an imaging technique that seems to show white-matter abnormalities resulting from tumour infiltration that cannot be visualised by conventional computed tomography or magnetic resonance imaging (MRI). We propose a new term, the image-based high-risk volume (IHV) for such abnormalities, which are distinct from the gross-tumour volume (GTV). For IHV based on DTI, we use the term IHVDTI. This study assesses the value of DTI for the individualisation of radiotherapy treatment planning for patients with HGG. Seven patients with biopsy-proven HGG were included in a theoretical planning exercise, comparing standard planning techniques with individualised plans based on DTI. Standard plans were generated using a 2.5 cm clinical target volume (CTV) margin added to the GTV. For DTI-based plans, the CTV was generated by adding a 1 cm margin to the IHVDTI. Estimates of normal tissue complication probability (NTCP) were calculated and used to estimate the level of dose escalation that could be achieved using the DTI-based plans. The use of DTI resulted in non-uniform margins being added to the GTV to encompass areas at high risk of tumour involvement, but, in six out of seven cases, the IHVDTI was encapsulated by the standard CTV margin. In all cases, DTI could be used to reduce the size of the planning-target volume (PTV) (mean 35%, range 18-46%), resulting in escalated doses (mean 67 Gy, range 64-74 Gy), with NTCP levels that matched the conventional treatment plans. DTI can be used to individualise radiotherapy target volumes, and reduction in the CTV permits modest dose escalation without an increase in NTCP. DTI may also be helpful in stratifying patients according to the degree of white-matter infiltration.

  8. Dermatologic radiotherapy in the treatment of extensive basal cell carcinomas: a retrospective study.

    PubMed

    Piccinno, R; Benardon, S; Gaiani, F M; Rozza, M; Caccialanza, M

    2017-08-01

    The increase of the number of new cases for year of basal cell carcinoma (BCC) has brought also an increase of BCC difficult to treat (extensive, locally advanced and high risk forms). To evaluate retrospectively the results obtained with dermatologic radiotherapy (RT) for better defining the indications respect to new emerging treatments. A series of extensive 115 BCC treated with RT from 1977 to 2014 were selected for the study, since endowed with histological diagnosis on the amount of 181 extensive BCC. RT was performed with conventional energies (50-160 kV) administering a total dose ranging from 47 to 85 Gy (median 55 Gy). The mean follow up was 40.66 months (median 21 months). A statistical evaluation was performed with chi-square test to analyse the possible correlations among therapeutic and cosmetic results and size, localisation and clinical type of the lesions. A complete remission (CR) was obtained in 70.43%, a partial remission (PR) in 20% of the lesions treated, while in 9.56% a no response (NR) or not evaluable response (NER) was registered. In 19% of the lesions a relapse was observed, with a five-year cure-rate of 55.13%. Cosmetic results were good in 28%, acceptable in 50% and not acceptable in 22% of the lesions in CR. In six lesions, localised at the trunk region, a chronic radiodermatitis developed. A statistically significative correlation was observed between therapeutic results and size, between cosmetic results and size and between therapeutic results and clinical type of BCC. The treatment of extensive BCC is still a challenge and radiotherapy is one of the possible choices, preferred in the elderly, in relapsing cases, after incomplete excision, and in difficult localisations of the face. Radiotherapy might be included in sequential schedules of treatment to improve final results.

  9. Improving the efficiency of breast radiotherapy treatment planning using a semi-automated approach.

    PubMed

    Mitchell, Robert A; Wai, Philip; Colgan, Ruth; Kirby, Anna M; Donovan, Ellen M

    2017-01-01

    To reduce treatment planning times while maintaining plan quality through the introduction of semi-automated planning techniques for breast radiotherapy. Automatic critical structure delineation was examined using the Smart Probabilistic Image Contouring Engine (SPICE) commercial autosegmentation software (Philips Radiation Oncology Systems, Fitchburg, WI) for a cohort of ten patients. Semiautomated planning was investigated by employing scripting in the treatment planning system to automate segment creation for breast step-and-shoot planning and create objectives for segment weight optimization; considerations were made for three different multileaf collimator (MLC) configurations. Forty patients were retrospectively planned using the script and a planning time comparison performed. The SPICE heart and lung outlines agreed closely with clinician-defined outlines (median Dice Similarity Coefficient > 0.9); median difference in mean heart dose was 0.0 cGy (range -10.8 to 5.4 cGy). Scripted treatment plans demonstrated equivalence with their clinical counterparts. No statistically significant differences were found for target parameters. Minimal ipsilateral lung dose increases were also observed. Statistically significant (P < 0.01) time reductions were achievable for MLCi and Agility MLC (Elekta Ltd, Crawley, UK) plans (median 4.9 and 5.9 min, respectively). The use of commercial autosegmentation software enables breast plan adjustment based on doses to organs at risk. Semi-automated techniques for breast radiotherapy planning offer modest reductions in planning times. However, in the context of a typical department's breast radiotherapy workload, minor savings per plan translate into greater efficiencies overall. © 2016 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  10. Magnitude, Impact, and Management of Respiration-induced Target Motion in Radiotherapy Treatment: A Comprehensive Review

    PubMed Central

    Yoganathan, S. A.; Maria Das, K. J.; Agarwal, Arpita; Kumar, Shaleen

    2017-01-01

    Tumors in thoracic and upper abdomen regions such as lungs, liver, pancreas, esophagus, and breast move due to respiration. Respiration-induced motion introduces uncertainties in radiotherapy treatments of these sites and is regarded as a significant bottleneck in achieving highly conformal dose distributions. Recent developments in radiation therapy have resulted in (i) motion-encompassing, (ii) respiratory gating, and (iii) tracking methods for adapting the radiation beam aperture to account for the respiration-induced target motion. The purpose of this review is to discuss the magnitude, impact, and management of respiration-induced tumor motion. PMID:28974854

  11. Treatment outcomes after adjuvant radiotherapy following surgery for patients with stage I endometrial cancer

    PubMed Central

    Kim, Jiyoung; Lee, Kyung-Ja; Park, Kyung-Ran; Ha, Boram; Kim, Yi-Jun; Jung, Wonguen; Lee, Rena; Kim, Seung Cheol; Moon, Hye Sung; Ju, Woong; Kim, Yun Hwan; Lee, Jihae

    2016-01-01

    Purpose The purpose of this study is to evaluate the treatment outcomes of adjuvant radiotherapy using vaginal brachytherapy (VB) with a lower dose per fraction and/or external beam radiotherapy (EBRT) following surgery for patients with stage I endometrial carcinoma. Materials and Methods The subjects were 43 patients with the International Federation of Gynecology and Obstetrics (FIGO) stage I endometrial cancer who underwent adjuvant radiotherapy following surgery between March 2000 and April 2014. Of these, 25 received postoperative VB alone, while 18 received postoperative EBRT to the whole pelvis; 3 of these were treated with EBRT plus VB. The median EBRT dose was 50.0 Gy (45.0–50.4 Gy) and the VB dose was 24 Gy in 6 fractions. Tumor dose was prescribed at a depth of 5 mm from the cylinder surface and delivered twice per week. Results The median follow-up period for all patients was 57 months (range, 9 to 188 months). Five-year disease-free survival (DFS) and overall survival (OS) for all patients were 92.5% and 95.3%, respectively. Adjuvant radiotherapy was performed according to risk factors and stage IB, grade 3 and lymphovascular invasion were observed more frequently in the EBRT group. Five-year DFS for EBRT and VB alone were 88.1% and 96.0%, respectively (p = 0.42), and 5-year OS for EBRT and VB alone were 94.4% and 96%, respectively (p = 0.38). There was no locoregional recurrence in any patient. Two patients who received EBRT and 1 patient who received VB alone developed distant metastatic disease. Two patients who received EBRT had severe complications, one each of grade 3 gastrointestinal complication and pelvic bone insufficiency fracture. Conclusion Adjuvant radiotherapy achieved high DFS and OS with acceptable toxicity in stage I endometrial cancer. VB (with a lower dose per fraction) may be a viable option for selected patients with early-stage endometrial cancer following surgery. PMID:27703126

  12. The role of texture analysis in imaging as an outcome predictor and potential tool in radiotherapy treatment planning

    PubMed Central

    Alobaidli, S; McQuaid, S; South, C; Prakash, V; Evans, P

    2014-01-01

    Predicting a tumour's response to radiotherapy prior to the start of treatment could enhance clinical care management by enabling the personalization of treatment plans based on predicted outcome. In recent years, there has been accumulating evidence relating tumour texture to patient survival and response to treatment. Tumour texture could be measured from medical images that provide a non-invasive method of capturing intratumoural heterogeneity and hence could potentially enable a prior assessment of a patient's predicted response to treatment. In this article, work presented in the literature regarding texture analysis in radiotherapy in relation to survival and outcome is discussed. Challenges facing integrating texture analysis in radiotherapy planning are highlighted and recommendations for future directions in research are suggested. PMID:25051978

  13. Intrathecal Methotrexate and Craniospinal Radiotherapy Can Be an Effective Treatment of Carcinomatous Meningitis in Patients with Breast Cancer: Case Reports

    PubMed Central

    Meissner, Magdalena; Addeo, Alfredo

    2016-01-01

    Introduction Carcinomatous meningitis in breast cancer occurs as a complication in up to 5% of all cases. It is a very devastating diagnosis, with a median patient survival of about 3 months. Treatment is very controversial, and different modalities of treatment have been used but none of them show significant benefit for overall survival. Case Reports We report 2 cases of carcinomatous meningitis in breast cancer patients. They received a similar treatment of a combination of intrathecal (IT) methotrexate followed by craniospinal radiotherapy. Both patients survived for many years after treatment and are in complete clinical and radiological remission. Conclusion Meningeal metastasis from breast cancer can be very effectively treated with IT and/or systemic chemotherapy followed by craniospinal radiotherapy. Further studies are needed to determine the effectiveness of this sequential combination of chemotherapy with radiotherapy. PMID:27920689

  14. SU-C-17A-07: The Development of An MR Accelerator-Enabled Planning-To-Delivery Technique for Stereotactic Palliative Radiotherapy Treatment of Spinal Metastases

    SciTech Connect

    Hoogcarspel, S J; Kontaxis, C; Velden, J M van der; Bol, G H; Vulpen, M van; Lagendijk, J J W; Raaymakers, B W

    2014-06-01

    Purpose: To develop an MR accelerator-enabled online planning-todelivery technique for stereotactic palliative radiotherapy treatment of spinal metastases. The technical challenges include; automated stereotactic treatment planning, online MR-based dose calculation and MR guidance during treatment. Methods: Using the CT data of 20 patients previously treated at our institution, a class solution for automated treatment planning for spinal bone metastases was created. For accurate dose simulation right before treatment, we fused geometrically correct online MR data with pretreatment CT data of the target volume (TV). For target tracking during treatment, a dynamic T2-weighted TSE MR sequence was developed. An in house developed GPU based IMRT optimization and dose calculation algorithm was used for fast treatment planning and simulation. An automatically generated treatment plan developed with this treatment planning system was irradiated on a clinical 6 MV linear accelerator and evaluated using a Delta4 dosimeter. Results: The automated treatment planning method yielded clinically viable plans for all patients. The MR-CT fusion based dose calculation accuracy was within 2% as compared to calculations performed with original CT data. The dynamic T2-weighted TSE MR Sequence was able to provide an update of the anatomical location of the TV every 10 seconds. Dose calculation and optimization of the automatically generated treatment plans using only one GPU took on average 8 minutes. The Delta4 measurement of the irradiated plan agreed with the dose calculation with a 3%/3mm gamma pass rate of 86.4%. Conclusions: The development of an MR accelerator-enabled planning-todelivery technique for stereotactic palliative radiotherapy treatment of spinal metastases was presented. Future work will involve developing an intrafraction motion adaptation strategy, MR-only dose calculation, radiotherapy quality-assurance in a magnetic field, and streamlining the entire treatment

  15. Boosting runtime-performance of photon pencil beam algorithms for radiotherapy treatment planning.

    PubMed

    Siggel, M; Ziegenhein, P; Nill, S; Oelfke, U

    2012-10-01

    Pencil beam algorithms are still considered as standard photon dose calculation methods in Radiotherapy treatment planning for many clinical applications. Despite their established role in radiotherapy planning their performance and clinical applicability has to be continuously adapted to evolving complex treatment techniques such as adaptive radiation therapy (ART). We herewith report on a new highly efficient version of a well-established pencil beam convolution algorithm which relies purely on measured input data. A method was developed that improves raytracing efficiency by exploiting the capability of modern CPU architecture for a runtime reduction. Since most of the current desktop computers provide more than one calculation unit we used symmetric multiprocessing extensively to parallelize the workload and thus decreasing the algorithmic runtime. To maximize the advantage of code parallelization, we present two implementation strategies - one for the dose calculation in inverse planning software, and one for traditional forward planning. As a result, we could achieve on a 16-core personal computer with AMD processors a superlinear speedup factor of approx. 18 for calculating the dose distribution of typical forward IMRT treatment plans. Copyright © 2011 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  16. Comparison of selected dose calculation algorithms in radiotherapy treatment planning for tissues with inhomogeneities

    NASA Astrophysics Data System (ADS)

    Woon, Y. L.; Heng, S. P.; Wong, J. H. D.; Ung, N. M.

    2016-03-01

    Inhomogeneity correction is recommended for accurate dose calculation in radiotherapy treatment planning since human body are highly inhomogeneous with the presence of bones and air cavities. However, each dose calculation algorithm has its own limitations. This study is to assess the accuracy of five algorithms that are currently implemented for treatment planning, including pencil beam convolution (PBC), superposition (SP), anisotropic analytical algorithm (AAA), Monte Carlo (MC) and Acuros XB (AXB). The calculated dose was compared with the measured dose using radiochromic film (Gafchromic EBT2) in inhomogeneous phantoms. In addition, the dosimetric impact of different algorithms on intensity modulated radiotherapy (IMRT) was studied for head and neck region. MC had the best agreement with the measured percentage depth dose (PDD) within the inhomogeneous region. This was followed by AXB, AAA, SP and PBC. For IMRT planning, MC algorithm is recommended for treatment planning in preference to PBC and SP. The MC and AXB algorithms were found to have better accuracy in terms of inhomogeneity correction and should be used for tumour volume within the proximity of inhomogeneous structures.

  17. Fractionated Stereotactic Radiotherapy in the Treatment of Vestibular Schwannoma (Acoustic Neuroma): Predicting the Risk of Hydrocephalus;Vestibular schwannoma; Hydrocephalus; Fractionated; Stereotactic radiotherapy

    SciTech Connect

    Powell, Ceri; Micallef, Caroline; Gonsalves, Adam; Wharram, Bev; Ashley, Sue; Brada, Michael

    2011-07-15

    Purpose: To determine the incidence and predictive factors for the development of hydrocephalus in patients with acoustic neuromas (AN) treated with fractionated stereotactic radiotherapy. Patients and Methods: Seventy-two patients with AN were treated with fractionated stereotactic radiotherapy between 1998 and 2007 (45-50 Gy in 25-30 fractions over 5 to 6 weeks). The pretreatment MRI scan was assessed for tumor characteristics and anatomic distortion independently of subsequent outcome and correlated with the risk of hydrocephalus. Results: At a median follow-up of 49 months (range, 1-120 months), 5-year event-free survival was 95%. Eight patients (11%) developed hydrocephalus within 19 months of radiotherapy, which was successfully treated. On univariate analysis, pretreatment factors predictive of hydrocephalus were maximum diameter (p = 0.005), proximity to midline (p = 0.009), displacement of the fourth ventricle (p = 0.02), partial effacement of the fourth ventricle (p < 0.001), contact with the medulla (p = 0.005), and more brainstem structures (p = 0.004). On multivariate analysis, after adjusting for fourth ventricular effacement, no other variables remained independently associated with hydrocephalus formation. Conclusions: Fractionated stereotactic radiotherapy results in excellent tumor control of AN, albeit with a risk of developing hydrocephalus. Patients at high risk, identified as those with larger tumors with partial effacement of the fourth ventricle before treatment, should be monitored more closely during follow-up. It would also be preferable to offer treatment to patients with progressive AN while the risk of hydrocephalus is low, before the development of marked distortion of fourth ventricle before tumor diameter significantly exceeds 2 cm.

  18. Stereotactic Fractionated Radiotherapy in the Treatment of Juxtapapillary Choroidal Melanoma: The McGill University Experience

    SciTech Connect

    Al-Wassia, Rolina; Dal Pra, Alan; Shun, Kitty; Shaban, Ahmed; Corriveau, Christine; Edelstein, Chaim; Deschenes, Jean; Ruo, Russel; Patrocinio, Horacio; Cury, Fabio L.B.; DeBlois, Francois; Shenouda, George

    2011-11-15

    Purpose: To report our experience with linear accelerator-based stereotactic fractionated radiotherapy in the treatment of juxtapapillary choroidal melanoma. Methods and Materials: We performed a retrospective review of 50 consecutive patients diagnosed with juxtapapillary choroidal melanoma and treated with linear accelerator-based stereotactic fractionated radiotherapy between April 2003 and December 2009. Patients with small to medium sized lesions (Collaborative Ocular Melanoma Study classification) located within 2 mm of the optic disc were included. The prescribed radiation dose was 60 Gy in 10 fractions. The primary endpoints included local control, enucleation-free survival, and complication rates. Results: The median follow-up was 29 months (range, 1-77 months). There were 31 males and 29 females, with a median age of 69 years (range, 30-92 years). Eighty-four percent of the patients had medium sized lesions, and 16% of patients had small sized lesions. There were four cases of local progression (8%) and three enucleations (6%). Actuarial local control rates at 2 and 5 years were 93% and 86%, respectively. Actuarial enucleation-free survival rates at 2 and 5 years were 94% and 84%, respectively. Actuarial complication rates at 2 and 5 years were 33% and 88%, respectively, for radiation-induced retinopathy; 9.3% and 46.9%, respectively, for dry eye; 12% and 53%, respectively, for cataract; 30% and 90%, respectively, for visual loss [Snellen acuity (decimal equivalent), <0.1]; 11% and 54%, respectively, for optic neuropathy; and 18% and 38%, respectively, for neovascular glaucoma. Conclusions: Linear accelerator-based stereotactic fractionated radiotherapy using 60 Gy in 10 fractions is safe and has an acceptable toxicity profile. It has been shown to be an effective noninvasive treatment for juxtapapillary choroidal melanomas.

  19. Physician Expectations of Treatment Outcomes for Patients With Brain Metastases Referred for Whole Brain Radiotherapy

    SciTech Connect

    Barnes, Elizabeth A.; Chow, Edward; Tsao, May N.; Bradley, Nicole M.; Doyle, Meagan; Li, Kathy; Lam, Kelvin; Danjoux, Cyril

    2010-01-15

    Purpose: Patients with advanced cancer are referred to our Rapid Response Radiotherapy Program for quick access to palliative radiotherapy. The primary objective of this prospective study was to determine the physician expectations of the treatment outcomes for patients with brain metastases referred for whole brain radiotherapy (WBRT). The secondary objectives were to determine the factors influencing the expectations and to examine the accuracy of the physician-estimated patient survival. Methods and Materials: Patients were identified during a 17-month period. The referring physicians were sent a survey by facsimile to be completed and returned before the patient consultation. Information was sought on the patient's disease status, the physician's expectations of WBRT, the estimated patient survival and performance status, and physician demographic data. Results: A total of 137 surveys were sent out, and the overall response rate was 57.7%. The median patient age was 66 years (range, 35-87), 78.5% had multiple brain metastases, 42.3% had a controlled primary tumor, and 62.3% had extracranial disease. WBRT was thought to stabilize neurologic symptoms, improve quality of life, and allow for a Decadron (dexamethasone) taper by >=94.9% of the referring physicians; 87.0% thought WBRT would improve performance status; 77.9% thought it would improve neurologic symptoms; and 40.8% thought it would improve survival. The referring physicians estimated patient survival as a median of 6.0 months; however, the actual survival was a median of 2.5 months, for a median individual difference of 1.9 months (p < .0001). Conclusion: Physicians referring patients with brain metastases for consideration of WBRT are often overly optimistic when estimating the clinical benefit of the treatment and overestimate patient survival. These findings highlight the need for education and additional research in this field.

  20. Postoperative electron beam radiotherapy for keloids: treatment outcome and factors associated with occurrence and recurrence.

    PubMed

    Lee, Sun Young; Park, Jin

    2015-02-01

    In the treatment of keloids, the recurrence after surgical excision is relatively high. Various types of adjuvant therapy such as radiotherapy and corticosteroid injection have been used to reduce the recurrence. The aim of this study was to determine the appropriate time for initiating postoperative radiotherapy and to analyze factors associated with the occurrence and recurrence of keloids. Of these 37 lesions, 22 were located in the ear lobe, 6 in the helix of the auricle, 4 on the shoulder, 3 on the chest wall, and 2 on the abdomen. Causative factors were piercings (n=24), trauma (n=5), previous surgical lesions or bacillus Calmette-Guerin vaccination lesions (n=3) and acne (n=2). Radiation therapy was initiated within 24 h in 24 lesions, between 24 and 72 h in 6 lesions, and after more than 72 h in 7 lesions. Seven lesions recurred, including 5 recurrences in high stretch-tension regions (p=0.010). Initial treatments were administered within 24 h in 1 lesion and more than 72 h after surgical excision in 6 lesions (p<0.0001). In the 19 patients with family histories, maternal and paternal genetic predispositions were present in 14 and 5 patients, respectively (p=0.033). Radiotherapy should be initiated within 72 h of surgical excision. Location in a high stretch-tension region was significantly associated with recurrence. Patients with a family history showed a significant tendency toward maternal genetic predisposition. Therefore, combination therapy should be considered to reduce the occurrence and recurrence of keloids, and careful observation is required.

  1. Preoperative radiotherapy for inoperable stage II endometrial cancer: insights into improving treatment and outcomes.

    PubMed

    Lee, Marette H; Aquino-Parsons, Christina; Hoskins, Paul J; Lim, Peter; Kwon, Janice S

    2013-07-01

    To review recurrence patterns and survival outcomes of women receiving preoperative radiotherapy for clinical stage II endometrial cancer in British Columbia. We performed a retrospective population-based cohort study of all patients with clinical stage II endometrial cancer who were referred to the British Columbia Cancer Agency from 2000 to 2008, deemed ineligible for primary surgery, and therefore offered preoperative radiotherapy followed by surgery. Patient demographics, uterine risk factors, timing and details of treatments, and timing and sites of recurrence were obtained from patient records. Primary outcome measures were the sites and rates of recurrence and recurrence-free survival. We identified 29 patients with a mean age of 61 years (range 41 to 83) and median follow-up of 3.1 years (range 0.3 to 5.3). Three-year overall survival was 79%, and median recurrence-free survival was 2.5 years. Eight patients had recurrence of disease (27.6%), with a median time to recurrence of 1.3 years, (range 0.4 to 2.7). Six of these eight women had two or more high-risk uterine factors (deep myometrial invasion, grade 3 tumour), ovarian involvement, or adverse histological type (carcinosarcoma), compared with only one of 21 patients without recurrence. Seven of eight women had recurrence outside the radiated volume of tissue. Median survival after recurrence was 1.0 years (range 0.4 to 2.2). Women with clinical stage II endometrial cancer had a significant risk of recurrence when treated with preoperative radiotherapy followed by surgery. They were more likely to have distant recurrences, implying the need for an alternate treatment paradigm.

  2. Radiation-induced temporo-mandibular joint disorder in post-radiotherapy nasopharyngeal carcinoma patients: assessment and treatment.

    PubMed

    Wu, Vincent W C; Lam, Ying-Na

    2016-06-01

    Nasopharyngeal carcinoma (NPC) is endemic in southern China, and its incidence in Hong Kong is relatively high. Radiotherapy is the mainstay treatment for NPC due to its relatively high radiosensitivity and deep-seated anatomical position, which is not readily accessible by surgery. Although the technique of radiotherapy in NPC has been advancing and offers promising treatment outcome, complications around the irradiation areas are inevitable and the quality of life of the post-radiotherapy patients is often compromised. Trismus, which is defined as the restricted mouth opening or jaw movement due to the disorder of temporo-mandibular joint (TMJ), is one of the possible late complications for radiotherapy of NPC and is found in 5-17% of the post-radiotherapy (post-RT) patients. Trismus at early stage may only affect the speech, but in severe cases nutritional intake and oral hygiene condition may deteriorate seriously. This article reviewed the possible causes of radiation-induced TMJ damage, the various assessments including imaging modalities and possible treatments. The conclusion is that the availability of simple, yet effective examinations for trismus is essential for delaying the progression and restoring TMJ functions. Although there is no absolutely effective treatment for trismus, many supportive, restorative and palliative management are possible under different clinical situations.

  3. [Extensor mechanism allograft and radiotherapy in the treatment of soft tissue sarcomas around the knee: Presentation of two clinical cases].

    PubMed

    Illana-Mahiques, M; Baixauli-García, F; Angulo-Sánchez, M A; Amaya-Valero, J V; García-Forcada, I L

    2015-01-01

    Knee involvement of soft tissue sarcomas is rare and very difficult to treat. Reconstruction of the extensor mechanism of the knee is essential to restore the functionality. Functional outcome is compromised by poor soft tissue coverage, adjuvant local radiotherapy, and resection of the extensor apparatus. No results were found in the literature as regards treatment by resection and reconstruction of the extensor mechanism in combination with adjuvant radiotherapy. The effects of radiotherapy are also unknown in the allografts. . Two cases are presented of soft tissue sarcoma around de knee treated by resection, reconstruction of the extensor mechanism with cryopreserved cadaver allograft, and local radiotherapy. After more than 3 years of follow up, both patients are free of disease and have a good joint balance. Resection of the tumor with adequate safety margins and reconstruction using cadaveric allograft preserves the extensor mechanism and function of the limb. The soft tissue coverage is an added problem that can be solved by propeller fasciocutaneous flap coverage. After surgery, the limb must be immobilized with a knee brace locked in extension. Local radiotherapy contributes to local control of the disease. The reconstruction of the extensor mechanism of the knee with allograft is a functional alternative to amputation, and it does not contraindicate adjuvant radiotherapy to improve local control of the disease. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

  4. Radiotherapy and Hyperthermia for Treatment of Primary Locally Advanced Cervix Cancer: Results in 378 Patients

    SciTech Connect

    Franckena, Martine Lutgens, Ludy C.; Koper, Peter C.; Kleynen, Catharina E.; Steen-Banasik, Elsbieta M. van der; Jobsen, Jan J.; Leer, Jan Willem; Creutzberg, Carien L.; Dielwart, Michel F.; Norden, Yvette van; Canters, Richard A.M.; Rhoon, Gerard C. van; Zee, Jacoba van der

    2009-01-01

    Purpose: To report response rate, pelvic tumor control, survival, and late toxicity after treatment with combined radiotherapy and hyperthermia (RHT) for patients with locally advanced cervical carcinoma (LACC) and compare the results with other published series. Methods and Materials: From 1996 to 2005, a total of 378 patients with LACC (International Federation of Gynecology and Obstetrics Stage IB2-IVA) were treated with RHT. External beam radiotherapy (RT) was applied to 46-50.4 Gy and combined with brachytherapy. The hyperthermia (HT) was prescribed once weekly. Primary end points were complete response (CR) and local control. Secondary end points were overall survival, disease-specific survival, and late toxicity. Patient, tumor, and treatment characteristics predictive for the end points were identified in univariate and multivariate analyses. Results: Overall, a CR was achieved in 77% of patients. At 5 years, local control, disease-specific survival, and incidence of late toxicity Common Terminology Criteria for Adverse Events Grade 3 or higher were 53%, 47%, and 12%, respectively. In multivariate analysis, number of HT treatments emerged as a predictor of outcome in addition to commonly identified prognostic factors. Conclusions: The CR, local control, and survival rates are similar to previously observed results of RHT in the randomized Dutch Deep Hyperthermia Trial. Reported treatment results for currently applied combined treatment modalities (i.e., RT with chemotherapy and/or HT) do not permit definite conclusions about which combination is superior. The present results confirm previously shown beneficial effects from adding HT to RT and justify the application of RHT as first-line treatment in patients with LACC as an alternative to chemoradiation.

  5. Involved field radiotherapy for limited stage Hodgkin lymphoma: balancing treatment efficacy against long-term toxicities.

    PubMed

    Goda, Jayant S; Tsang, Richard W

    2009-09-01

    Limited stage Hodgkin lymphoma (HL) refers to patients with stage IA or IIA disease in the absence of any bulky mass or unfavourable prognostic factors. In this group, the long-term disease control with treatment can be expected in more than 90%, and management has now been directed to make strategies to reduce late morbidities related to therapy. With the advent of very effective chemotherapy, the role of radiation therapy has evolved from a first line single modality treatment, to an adjuvant therapy following brief cycles of chemotherapy. Optimal radiation volume and dose parameters have been refined in the combined modality setting. Furthermore, with the progress in diagnostic functional imaging and advances in radiotherapy, it is possible to accurately deliver low to moderate doses of radiation to defined regions resulting in durable control of disease. This review will evaluate the literature that shapes the current standard of care in limited stage Hodgkin lymphoma with special emphasis on the use of limited field radiotherapy.

  6. Analysis of electromagnetic transponders tracking data to quantify intrafraction prostate motion during radiotherapy treatments

    NASA Astrophysics Data System (ADS)

    Carrara, M.; Giandini, T.; Bonfantini, F.; Avuzzi, B.; Villa, S.; Bedini, N.; Morlino, S.; Carabelli, G.; Frasca, S.; Valdagni, R.; Pignoli, E.

    2017-02-01

    The Calypso tracking system (Varian, Palo Alto, CA, USA) is used to track the prostate isocenter on patients undergoing prostate radiotherapy after implantation of electromagnetic transponders. Aim of this study was to assign 226 recorded prostate tracks to different patterns of prostate intrafraction motion (i.e. stable target (ST), continuous target drift (CTD) and irregular wave motion (IWM)) and excursion (i.e. transient excursion (TE), persistent excursion (PE) and high-frequency excursion (HFE)). Relative frequencies of STs, CTDs and IWMs were 51.8%, 44.6% and 3.6%, respectively. TEs, PEs and HFEs were revealed in 9.4%, 5.4% and 14.3% cases, respectively, with maximum values of 8.0 mm, 8.7 mm and 15.5 mm, respectively. The equation D(t) = 8.0*10-3 mm/s * t + 0.93 mm was established to calculate the average prostate drift D with time t. Intrafraction prostate motion and excursions can be significant and should be in particular taken into account with treatment deliveries that require a prolonged treatment time, as for instance stereotactic body radiotherapy (SBRT) or hadrontherapy.

  7. Concurrent multimodality image segmentation by active contours for radiotherapy treatment planning

    SciTech Connect

    El Naqa, Issam; Yang Deshan; Apte, Aditya; Khullar, Divya; Mutic, Sasa; Zheng Jie; Bradley, Jeffrey D.; Grigsby, Perry; Deasy, Joseph O.

    2007-12-15

    Multimodality imaging information is regularly used now in radiotherapy treatment planning for cancer patients. The authors are investigating methods to take advantage of all the imaging information available for joint target registration and segmentation, including multimodality images or multiple image sets from the same modality. In particular, the authors have developed variational methods based on multivalued level set deformable models for simultaneous 2D or 3D segmentation of multimodality images consisting of combinations of coregistered PET, CT, or MR data sets. The combined information is integrated to define the overall biophysical structure volume. The authors demonstrate the methods on three patient data sets, including a nonsmall cell lung cancer case with PET/CT, a cervix cancer case with PET/CT, and a prostate patient case with CT and MRI. CT, PET, and MR phantom data were also used for quantitative validation of the proposed multimodality segmentation approach. The corresponding Dice similarity coefficient (DSC) was 0.90{+-}0.02 (p<0.0001) with an estimated target volume error of 1.28{+-}1.23% volume. Preliminary results indicate that concurrent multimodality segmentation methods can provide a feasible and accurate framework for combining imaging data from different modalities and are potentially useful tools for the delineation of biophysical structure volumes in radiotherapy treatment planning.

  8. Upfront gefitinib/erlotinib treatment followed by concomitant radiotherapy for advanced lung cancer: a mono-institutional experience.

    PubMed

    Chang, Chih-Chia; Chi, Kwan-Hwa; Kao, Shang-Jyh; Hsu, Pei-Sung; Tsang, Yuk-Wah; Chang, Heng-Jui; Yeh, Yu-Wung; Hsieh, Yei-San; Jiang, Jiunn-Song

    2011-08-01

    Upfront tyrosine kinase inhibitor (TKI) has proved effective for selective advanced lung cancer patients in Taiwan. We hypothesized that early integration of radiotherapy during TKI treatment would decrease the chance of drug resistance and prolong progression-free survival (PFS). This study included 25 patients with stage IIIb or IV non-squamous cell, non-small cell lung cancer (NSqCLC) who responded to upfront TKI treatment. Multi-target radiotherapy was administered during the TKI treatment course. Tomotherapy comprising a hypofractionated schedule with a dose of 40-50 Gy in 16-20 fractions was used for individual metastatic lesions. The patients' median follow-up duration was 30 months (range, 9-62 months). Of the 23 patients who had stage IV disease, 9 had oligometastases (≤5 gross target volumes) and 14 were in the more advanced stages of the disease. Twelve patients received more than 1 cycle of radiotherapy (median, 3; range, 2-6) with TKI being the only systemic treatment before they were salvaged with chemotherapy. The overall response rate after radiotherapy was 84.0%, and the median PFS was 16 months. The 3-year overall survival rate was 62.5% (95% confidence interval [CI], 39.1-85.8%). Toxicities were generally tolerated but it is necessary to prevent radiation-induced pneumonitis. We showed that combined first-line TKI therapy and early multi-target radiotherapy are very effective in selected patients that respond to TKI, when the status of mutations in the epidermal growth factor receptor (EGFR) are not known before the treatment. Our data may aid expansion of the effectiveness of TKI treatment through radiotherapy in Asian patients with stage IV NSqCLC. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  9. RTtxGap: An android radiobiological tool for compensation of radiotherapy treatment interruption

    NASA Astrophysics Data System (ADS)

    Yusoff, A. L.; Mohamad, M.; Abdullah, R.; Bhavaraju, V. M. K.; Nik Idris, N. R.

    2016-03-01

    Treatment interruption is not uncommon in radiotherapy. Common reasons for treatment interruption include machine breakdown, holidays and patient severe radiation reactions. Here RTtxGap, an Android application to assist calculations of compensation for treatment gap, is reported. It uses linear quadratic (LQ) model to calculate the biological effective dose (BED) that is used to solve for treatment gap compensations. Solutions are calculated using BED equation, with consideration for tissue proliferation. The accuracy of results has been verified using LQL Equiv software to be accurate within 1%. Five treatment interruption examples were used to illustrate the capability of the software to calculate the treatment compensation schedules. Solving these examples also illustrates the general consensus regarding compensating for unscheduled treatment interruptions, which ultimately involves balancing the BEDs of tumour and organ at risk. In addition to compensation for treatment gap, RTtxGap can also be used to calculate equivalent total dose in 2-Gy fraction (EQD2), to modify treatment schedule and to calculate alternative dose prescriptions having the same isoeffect.

  10. Glioblastoma Treatment: Bypassing the Toxicity of Platinum Compounds by Using Liposomal Formulation and Increasing Treatment Efficiency With Concomitant Radiotherapy

    SciTech Connect

    Charest, Gabriel; Sanche, Leon; Fortin, David; Mathieu, David; Paquette, Benoit

    2012-09-01

    Purpose: Treatments of glioblastoma with cisplatin or oxaliplatin only marginally improve the overall survival of patients and cause important side effects. To prevent adverse effects, improve delivery, and optimize the tumor response to treatment in combination with radiotherapy, a potential approach consists of incorporating the platinum agent in a liposome. Methods and Materials: In this study, cisplatin, oxaliplatin, carboplatin, Lipoplatin (the liposomal formulation of cisplatin), and Lipoxal (the liposomal formulation of oxaliplatin) were tested on F98 glioma orthotopically implanted in Fischer rats. The platinum compounds were administered by intracarotid infusion and were assessed for the ability to reduce toxicity, improve cancer cell uptake, and increase survival of animals when combined or not combined with radiotherapy. Results: The tumor uptake was 2.4-fold more important for Lipoxal than the liposome-free oxaliplatin. Lipoxal also improved the specificity of oxaliplatin as shown by a higher ratio of tumor to right hemisphere uptake. Surprisingly, Lipoplatin led to lower tumor uptake compared with cisplatin. However, Lipoplatin had the advantage of largely reducing the toxicity of cisplatin and allowed us to capitalize on the anticancer activity of this agent. Conclusion: Among the five platinum compounds tested, carboplatin showed the best increase in survival when combined with radiation for treatment of glioma implanted in Fischer rats.

  11. Multiobjective optimization with a modified simulated annealing algorithm for external beam radiotherapy treatment planning

    SciTech Connect

    Aubry, Jean-Francois; Beaulieu, Frederic; Sevigny, Caroline; Beaulieu, Luc; Tremblay, Daniel

    2006-12-15

    Inverse planning in external beam radiotherapy often requires a scalar objective function that incorporates importance factors to mimic the planner's preferences between conflicting objectives. Defining those importance factors is not straightforward, and frequently leads to an iterative process in which the importance factors become variables of the optimization problem. In order to avoid this drawback of inverse planning, optimization using algorithms more suited to multiobjective optimization, such as evolutionary algorithms, has been suggested. However, much inverse planning software, including one based on simulated annealing developed at our institution, does not include multiobjective-oriented algorithms. This work investigates the performance of a modified simulated annealing algorithm used to drive aperture-based intensity-modulated radiotherapy inverse planning software in a multiobjective optimization framework. For a few test cases involving gastric cancer patients, the use of this new algorithm leads to an increase in optimization speed of a little more than a factor of 2 over a conventional simulated annealing algorithm, while giving a close approximation of the solutions produced by a standard simulated annealing. A simple graphical user interface designed to facilitate the decision-making process that follows an optimization is also presented.

  12. Reenlargement of radiation necrosis after stereotactic radiotherapy for brain metastasis from lung cancer during bevacizumab treatment.

    PubMed

    Furuuchi, Koji; Nishiyama, Akihiro; Yoshioka, Hiroshige; Yokoyama, Toshihide; Ishida, Tadashi

    2017-03-01

    We describe a 55-year-old man who received stereotactic radiotherapy (SRT) for the treatment of brain metastasis from lung adenocarcinoma. Fourteen months after SRT, right-sided hemiparesis developed, and magnetic resonance imaging revealed progression of perifocal edema and an enhanced lesion. Cerebral radiation necrosis was diagnosed, and treatment with bevacizumab was initiated. The lesion clearly responded to bevacizumab therapy, but reenlarged 8 months later and was surgically resected. Histopathological analysis of the resected specimen revealed large areas of necrosis; however, viable tumor cells were detected in the necrotic areas. Reenlargement of the necrotic lesion was attributed to the recurrence of lung cancer. Copyright © 2016 The Japanese Respiratory Society. Published by Elsevier B.V. All rights reserved.

  13. Treatment of equine cutaneous neoplasia by radiotherapy using iridium 192 linear sources.

    PubMed

    Wyn-Jones, G

    1983-10-01

    The treatment of equine cutaneous tumours by conventional or cryosurgical techniques can be limited where the position of the tumour makes radical excision or freezing impractical or dangerous. Radiotherapy provides an effective and practical alternative. The use of iridium pins with guide needles allows accurate positioning of sources and uniform radiation fields to be achieved. The subsequent removal of the pins reduces the period of incapacity and reduces the radiation risk when compared to permanently implanted sources. Twenty-seven tumours on 26 horses were treated by this method with a 100 per cent success rate after a single irradiation. The technique of implantation is described and the criteria used to select cases and to assess the efficacy of this treatment are discussed.

  14. A One-Step Cone-Beam CT-Enabled Planning-to-Treatment Model for Palliative Radiotherapy-From Development to Implementation

    SciTech Connect

    Wong, Rebecca K.S.; Letourneau, Daniel; Varma, Anita; Bissonnette, Jean Pierre; Fitzpatrick, David; Grabarz, Daniel; Elder, Christine; Martin, Melanie; Bezjak, Andrea; Panzarella, Tony; Gospodarowicz, Mary; Jaffray, David A.

    2012-11-01

    Purpose: To develop a cone-beam computed tomography (CT)-enabled one-step simulation-to-treatment process for the treatment of bone metastases. Methods and Materials: A three-phase prospective study was conducted. Patients requiring palliative radiotherapy to the spine, mediastinum, or abdomen/pelvis suitable for treatment with simple beam geometry ({<=}2 beams) were accrued. Phase A established the accuracy of cone-beam CT images for the purpose of gross tumor target volume (GTV) definition. Phase B evaluated the feasibility of implementing the cone-beam CT-enabled planning process at the treatment unit. Phase C evaluated the online cone-beam CT-enabled process for the planning and treatment of patients requiring radiotherapy for bone metastases. Results: Eighty-four patients participated in this study. Phase A (n = 9) established the adequacy of cone-beam CT images for target definition. Phase B (n = 45) established the quality of treatment plans to be adequate for clinical implementation for bone metastases. When the process was applied clinically in bone metastases (Phase C), the degree of overlap between planning computed tomography (PCT) and cone-beam CT for GTV and between PCT and cone-beam CT for treatment field was 82% {+-} 11% and 97% {+-} 4%, respectively. The oncologist's decision to accept the plan under a time-pressured environment remained of high quality, with the cone-beam CT-generated treatment plan delivering at least 90% of the prescribed dose to 100% {+-} 0% of the cone-beam CT planning target volume (PTV). With the assumption that the PCT PTV is the gold-standard target, the cone-beam CT-generated treatment plan delivered at least 90% and at least 95% of dose to 98% {+-} 2% and 97% {+-} 5% of the PCT PTV, respectively. The mean time for the online planning and treatment process was 32.7 {+-} 4.0 minutes. Patient satisfaction was high, with a trend for superior satisfaction with the cone-beam CT-enabled process. Conclusions: The cone-beam CT

  15. A one-step cone-beam CT-enabled planning-to-treatment model for palliative radiotherapy-from development to implementation.

    PubMed

    Wong, Rebecca K S; Letourneau, Daniel; Varma, Anita; Bissonnette, Jean Pierre; Fitzpatrick, David; Grabarz, Daniel; Elder, Christine; Martin, Melanie; Bezjak, Andrea; Panzarella, Tony; Gospodarowicz, Mary; Jaffray, David A

    2012-11-01

    To develop a cone-beam computed tomography (CT)-enabled one-step simulation-to-treatment process for the treatment of bone metastases. A three-phase prospective study was conducted. Patients requiring palliative radiotherapy to the spine, mediastinum, or abdomen/pelvis suitable for treatment with simple beam geometry (≤2 beams) were accrued. Phase A established the accuracy of cone-beam CT images for the purpose of gross tumor target volume (GTV) definition. Phase B evaluated the feasibility of implementing the cone-beam CT-enabled planning process at the treatment unit. Phase C evaluated the online cone-beam CT-enabled process for the planning and treatment of patients requiring radiotherapy for bone metastases. Eighty-four patients participated in this study. Phase A (n = 9) established the adequacy of cone-beam CT images for target definition. Phase B (n = 45) established the quality of treatment plans to be adequate for clinical implementation for bone metastases. When the process was applied clinically in bone metastases (Phase C), the degree of overlap between planning computed tomography (PCT) and cone-beam CT for GTV and between PCT and cone-beam CT for treatment field was 82% ± 11% and 97% ± 4%, respectively. The oncologist's decision to accept the plan under a time-pressured environment remained of high quality, with the cone-beam CT-generated treatment plan delivering at least 90% of the prescribed dose to 100% ± 0% of the cone-beam CT planning target volume (PTV). With the assumption that the PCT PTV is the gold-standard target, the cone-beam CT-generated treatment plan delivered at least 90% and at least 95% of dose to 98% ± 2% and 97% ± 5% of the PCT PTV, respectively. The mean time for the online planning and treatment process was 32.7 ± 4.0 minutes. Patient satisfaction was high, with a trend for superior satisfaction with the cone-beam CT-enabled process. The cone-beam CT-enabled palliative treatment process is feasible and is ready for

  16. Radiotherapy in conjunction with superficial and intracavitary hyperthermia for the treatment of solid tumors: survival and thermal parameters.

    PubMed

    Triantopoulou, S; Efstathopoulos, E; Platoni, K; Uzunoglou, N; Kelekis, N; Kouloulias, V

    2013-02-01

    Hyperthermia is an effective modality for the treatment of cancer, which is mainly used in conjunction with radiotherapy as this combined treatment offers a better clinical outcome. There are many ways that hyperthermia can be applied and depends on the kind of tumor of the patients. The great advantage of this method is that it is tolerable for the majority of patients without severe toxicity. Many clinical trials have been realized in order to prove that hyperthermia in addition to radiotherapy offers an advantage in the survival and local control of patients in comparison to radiotherapy alone. Many studies have also investigated if exists any correlation between the thermal parameters of hyperthermia and the clinical outcome. This is a review of these studies and it concerns superficial hyperthermia for superficial tumors-melanoma, head and neck, breast cancer-and intracavitary hyperthermia for rectal cancer, esophageal cancer and prostate carcinoma.

  17. Dosimetric Evaluation of Intensity Modulated Radiotherapy and 4-Field 3-D Conformal Radiotherapy in Prostate Cancer Treatment

    PubMed Central

    Uysal, Bora; Beyzadeoğlu, Murat; Sager, Ömer; Dinçoğlan, Ferrat; Demiral, Selçuk; Gamsız, Hakan; Sürenkök, Serdar; Oysul, Kaan

    2013-01-01

    Objective: The purpose of this dosimetric study is the targeted dose homogeneity and critical organ dose comparison of 7-field Intensity Modulated Radiotherapy (IMRT) and 3-D 4-field conformal radiotherapy. Study Design: Cross sectional study. Material and Methods: Twenty patients with low and moderate risk prostate cancer treated at Gülhane Military Medical School Radiation Oncology Department between January 2009 and December 2009 are included in this study. Two seperate dosimetric plans both for 7-field IMRT and 3D-CRT have been generated for each patient to comparatively evaluate the dosimetric status of both techniques and all the patients received 7-field IMRT. Results: Dose-comparative evaluation of two techniques revealed the superiority of IMRT technique with statistically significantly lower femoral head doses along with reduced critical organ dose-volume parameters of bladder V60 (the volume receiving 60 Gy) and rectal V40 (the volume receiving 40 Gy) and V60. Conclusion: It can be concluded that IMRT is an effective definitive management tool for prostate cancer with improved critical organ sparing and excellent dose homogenization in target organs of prostate and seminal vesicles. PMID:25207069

  18. Monte Carlo treatment planning with modulated electron radiotherapy: framework development and application

    NASA Astrophysics Data System (ADS)

    Alexander, Andrew William

    Within the field of medical physics, Monte Carlo radiation transport simulations are considered to be the most accurate method for the determination of dose distributions in patients. The McGill Monte Carlo treatment planning system (MMCTP), provides a flexible software environment to integrate Monte Carlo simulations with current and new treatment modalities. A developing treatment modality called energy and intensity modulated electron radiotherapy (MERT) is a promising modality, which has the fundamental capabilities to enhance the dosimetry of superficial targets. An objective of this work is to advance the research and development of MERT with the end goal of clinical use. To this end, we present the MMCTP system with an integrated toolkit for MERT planning and delivery of MERT fields. Delivery is achieved using an automated "few leaf electron collimator" (FLEC) and a controller. Aside from the MERT planning toolkit, the MMCTP system required numerous add-ons to perform the complex task of large-scale autonomous Monte Carlo simulations. The first was a DICOM import filter, followed by the implementation of DOSXYZnrc as a dose calculation engine and by logic methods for submitting and updating the status of Monte Carlo simulations. Within this work we validated the MMCTP system with a head and neck Monte Carlo recalculation study performed by a medical dosimetrist. The impact of MMCTP lies in the fact that it allows for systematic and platform independent large-scale Monte Carlo dose calculations for different treatment sites and treatment modalities. In addition to the MERT planning tools, various optimization algorithms were created external to MMCTP. The algorithms produced MERT treatment plans based on dose volume constraints that employ Monte Carlo pre-generated patient-specific kernels. The Monte Carlo kernels are generated from patient-specific Monte Carlo dose distributions within MMCTP. The structure of the MERT planning toolkit software and

  19. Feasibility of using glass-bead thermoluminescent dosimeters for radiotherapy treatment plan verification

    PubMed Central

    Jordan, Tom J; Distefano, Gail; Bradley, David A; Spyrou, Nicholas M; Nisbet, Andrew; Clark, Catharine H

    2015-01-01

    Objective: To investigate the feasibility of using glass beads as novel thermoluminescent dosemeters (TLDs) for radiotherapy treatment plan verification. Methods: Commercially available glass beads with a size of 1-mm thickness and 2-mm diameter were characterized as TLDs. Five clinical treatment plans including a conventional larynx, a conformal prostate, an intensity-modulated radiotherapy (IMRT) prostate and two stereotactic body radiation therapy (SBRT) lung plans were transferred onto a CT scan of a water-equivalent phantom (Solid Water®, Gammex, Middleton, WI) and the dose distribution recalculated. The number of monitor units was maintained from the clinical plan and delivered accordingly. The doses determined by the glass beads were compared with those measured by a graphite-walled ionization chamber, and the respective expected doses were determined by the treatment-planning system (TPS) calculation. Results: The mean percentage difference between measured dose with the glass beads and TPS was found to be 0.3%, −0.1%, 0.4%, 1.8% and 1.7% for the conventional larynx, conformal prostate, IMRT prostate and each of the SBRT delivery techniques, respectively. The percentage difference between measured dose with the ionization chamber and glass bead was found to be −1.2%, −1.4%, −0.1%, −0.9% and 2.4% for the above-mentioned plans, respectively. The results of measured doses with the glass beads and ionization chamber in comparison with expected doses from the TPS were analysed using a two-sided paired t-test, and there was no significant difference at p < 0.05. Conclusion: It is feasible to use glass-bead TLDs as dosemeters in a range of clinical plan verifications. Advances in knowledge: Commercial glass beads are utilized as low-cost novel TLDs for treatment-plan verification. PMID:26258442

  20. Sparing level Ib lymph nodes by intensity-modulated radiotherapy in the treatment of nasopharyngeal carcinoma.

    PubMed

    Chen, Jing; Ou, Dan; He, Xiayun; Hu, Chaosu

    2014-12-01

    We retrospectively investigated the patterns of locoregional relapse and survival of patients to evaluate whether sparing level Ib lymph nodes by intensity-modulated radiotherapy (IMRT) in the treatment of nasopharyngeal carcinoma was feasible. One hundred and twenty nasopharyngeal carcinoma patients received treatment with level Ib lymph nodes spared by IMRT between January 2005 and August 2008 in our center. Before treatment, each patient underwent enhanced magnetic resonance imaging of the nasopharynx and neck. Patients with negative cervical lymph nodes received radiotherapy to the nasopharynx, skull base and upper neck drainage areas, while patients with cervical lymph node involvement received treatment to the whole neck. The prescription doses were 66-70.4 Gy/30-32 fractions to the gross tumor volume of nasopharynx, 66 Gy to the positive neck nodes, 60 Gy to the high-risk clinical target volume and 54 Gy to the low-risk clinical target volume. Patients staged III, IV A/B or II also received chemotherapy. The median follow-up of these 120 patients was 54 months. The 5-year local control, regional control, distant metastasis-free and overall survival rates were 90.7, 96.5, 84.8 and 81.4 %, respectively. Four patients suffered regional recurrence: 2, 1 and 1 experienced regional recurrence in level II, retropharyngeal and parotid lymph nodes, respectively. In nasopharyngeal carcinoma patients with negative level Ib lymph nodes who are treated with level Ib-sparing IMRT, regional lymph node recurrence alone is rare. Therefore, sparing level Ib lymph nodes by IMRT is feasible in selected patients.

  1. Feasibility of using glass-bead thermoluminescent dosimeters for radiotherapy treatment plan verification.

    PubMed

    Jafari, Shakardokht M; Jordan, Tom J; Distefano, Gail; Bradley, David A; Spyrou, Nicholas M; Nisbet, Andrew; Clark, Catharine H

    2015-01-01

    To investigate the feasibility of using glass beads as novel thermoluminescent dosemeters (TLDs) for radiotherapy treatment plan verification. Commercially available glass beads with a size of 1-mm thickness and 2-mm diameter were characterized as TLDs. Five clinical treatment plans including a conventional larynx, a conformal prostate, an intensity-modulated radiotherapy (IMRT) prostate and two stereotactic body radiation therapy (SBRT) lung plans were transferred onto a CT scan of a water-equivalent phantom (Solid Water(®), Gammex, Middleton, WI) and the dose distribution recalculated. The number of monitor units was maintained from the clinical plan and delivered accordingly. The doses determined by the glass beads were compared with those measured by a graphite-walled ionization chamber, and the respective expected doses were determined by the treatment-planning system (TPS) calculation. The mean percentage difference between measured dose with the glass beads and TPS was found to be 0.3%, -0.1%, 0.4%, 1.8% and 1.7% for the conventional larynx, conformal prostate, IMRT prostate and each of the SBRT delivery techniques, respectively. The percentage difference between measured dose with the ionization chamber and glass bead was found to be -1.2%, -1.4%, -0.1%, -0.9% and 2.4% for the above-mentioned plans, respectively. The results of measured doses with the glass beads and ionization chamber in comparison with expected doses from the TPS were analysed using a two-sided paired t-test, and there was no significant difference at p < 0.05. It is feasible to use glass-bead TLDs as dosemeters in a range of clinical plan verifications. Commercial glass beads are utilized as low-cost novel TLDs for treatment-plan verification.

  2. Ascorbic-acid Treatment for Progressive Bone Metastases After Radiotherapy: A Pilot Study.

    PubMed

    Kiziltan, Huriye Senay; Bayir, Ayse Gunes; Demirtas, Murat; Meral, Ismail; Taspinar, Ozgur; Eris, Ali Hikmet; Aydin, Teoman; Mayadagli, Alparslan

    2014-10-01

    Context • Researchers have reported improved survival rates for patients with cancer when 10-75 g of vitamin C (ascorbic acid, or AA) is administered intravenously. AA exhibits a cytotoxic effect upon entering a cancer cell. Objective • The current study examined the benefits of intravenous administration of AA in treatment of bone metastases. Design • The study was a pilot study. Setting • The study was performed at Bezmialem Vakif University Medical Facility (BVUMF) in the Department of Radiation Oncology, from 2010-2012. Participants • Participants were 11 cancer patients with bone metastases who were unresponsive to standard cancer treatments and who experienced the following issues after receiving a total of 3000 cGy of radiotherapy: (1) intensifying pain, (2) an increase in metastatic sites, and/or (3) a deterioration in general health. Intervention • The 11 patients received 2.5 g of AA in a physiological saline solution, within 1 h period with 3-10 applications following at 1-wk intervals. Outcome Measures • The ECOG Performance Scale and Visual Analog Scale were used to assess performance and pain. Results • Among the participants administered AA, the mean reduction in pain was 55%, and the median survival time was 10 mo. Participants experienced a 40% grade-I gastrointestinal toxicity and a 30% urinary toxicity. Conclusions • Given the study's results, the current research team found considerable encouragement in the use of AA after radiotherapy for treatment of patients with bone metastases. Toxicity was in the acceptable range for AA treatment.

  3. Radiotherapy for testicular seminoma stage I: treatment results and long-term post-irradiation morbidity in 365 patients

    SciTech Connect

    Fossa, S.D.A.; Aass, N.; Kaalhus, O.

    1989-02-01

    After infradiaphragmatic radiotherapy the cancer-related 10 year survival was 99% in 365 patients with seminoma Stage I referred to the Norwegian Radium Hospital between 1970 and 1982. Thirteen patients relapsed, 11 of them within the first 3 years after treatment. Nine of the recurrent patients were cured by radiotherapy alone (4) or in combination with chemotherapy (5). There is no need to include the inguinal lymph nodes into the irradiation field or to give scrotal irradiation, not even to patients with tumor infiltration beyond the testicular tissue, or to those with prior scrotal or inguinal surgery. At least 1 year after radiotherapy moderate or more severe dyspepsia was observed in 16 patients. Nine patients developed a peptic ulcer. In general, there was no increased risk for development of a second non-germ cell cancer after radiotherapy. However, 4 patients developed a pulmonary cancer indicating a border-line significance of increased risk for this type of malignancy. (p:0.05). In conclusion, infradiaphragmatic radiotherapy remains the optimal routine treatment in seminoma patients with Stage I.

  4. Intensity modulated neutron radiotherapy for the treatment of adenocarcinoma of the prostate.

    PubMed

    Santanam, Lakshmi; He, Tony; Yudelev, Mark; Forman, Jeffrey D; Orton, Colin G; Heuvel, Frank Vanden; Maughan, Richard L; Burmeister, Jay

    2007-08-01

    This study investigates the enhanced conformality of neutron dose distributions obtainable through the application of intensity modulated neutron radiotherapy (IMNRT) to the treatment of prostate adenocarcinoma. An in-house algorithm was used to optimize individual segments for IMNRT generated using an organ-at-risk (OAR) avoidance approach. A number of beam orientation schemes were investigated in an attempt to approach an optimum solution. The IMNRT plans were created retrospectively for 5 patients previously treated for prostate adenocarcinoma using fast neutron therapy (FNT), and a comparison of these plans is presented. Dose distributions and dose-volume histograms (DVHs) were analyzed and plans were evaluated based on percentage volumes of rectum and bladder receiving 95%, 80%, and 50% (V(95), V(80), V(50)) of the prescription dose, and on V(60) for both the femoral heads and GM(muscle) group. Plans were normalized such that the IMNRT DVHs for prostate and seminal vesicles were nearly identical to those for conventional FNT plans. Use of IMNRT provided reductions in rectum V(95) and V(80) of 10% (2-27%) and 13% (5-28%), respectively, and reductions in bladder V(95) and V(80) of 12% (3-26%) and 4% (7-10%), respectively. The average decrease in V(60) for the femoral heads was 4.5% (1-18%), with no significant change in V(60) for the GM(muscle) group. This study provides the first analysis of the application of intensity modulation to neutron radiotherapy. The IMNRT technique provides a substantial reduction in normal tissue dose in the treatment of prostate cancer. This reduction should result in a significant clinical advantage for this and other treatment sites.

  5. SU-C-17A-01: MRI-Based Radiotherapy Treatment Planning In Pelvis

    SciTech Connect

    Hsu, S; Cao, Y; Jolly, S; Balter, J

    2014-06-15

    Purpose: To support radiotherapy dose calculation, synthetic CT (MRCT) image volumes need to represent the electron density of tissues with sufficient accuracy. This study compares CT and MRCT for pelvic radiotherapy. Methods: CT and multi-contrast MRI acquired using T1- based Dixon, T2 TSE, and PETRA sequences were acquired on an IRBapproved protocol patient. A previously published method was used to create a MRCT image volume by applying fuzzy classification on T1- weighted and calculated water image volumes (air and fluid voxels were excluded using thresholds applied to PETRA and T2-weighted images). The correlation of pelvic bone intensity between CT and MRCT was investigated. Two treatment plans, based on CT and MRCT, were performed to mimic treatment for: (a) pelvic bone metastasis with a 16MV parallel beam arrangement, and (b) gynecological cancer with 6MV volumetric modulated arc therapy (VMAT) using two full arcs. The CT-calculated fluence maps were used to recalculate doses using the MRCT-derived density grid. The dose-volume histograms and dose distributions were compared. Results: Bone intensities in the MRCT volume correlated linearly with CT intensities up to 800 HU (containing 96% of the bone volume), and then decreased with CT intensity increase (4% volume). There was no significant difference in dose distributions between CT- and MRCTbased plans, except for the rectum and bladder, for which the V45 differed by 15% and 9%, respectively. These differences may be attributed to normal and visualized organ movement and volume variations between CT and MR scans. Conclusion: While MRCT had lower bone intensity in highly-dense bone, this did not cause significant dose deviations from CT due to its small percentage of volume. These results indicate that treatment planning using MRCT could generate comparable dose distributions to that using CT, and further demonstrate the feasibility of using MRI-alone to support Radiation Oncology workflow. NIH R01EB016079.

  6. Dose mapping sensitivity to deformable registration uncertainties in fractionated radiotherapy - applied to prostate proton treatments.

    PubMed

    Tilly, David; Tilly, Nina; Ahnesjö, Anders

    2013-06-14

    Calculation of accumulated dose in fractionated radiotherapy based on spatial mapping of the dose points generally requires deformable image registration (DIR). The accuracy of the accumulated dose thus depends heavily on the DIR quality. This motivates investigations of how the registration uncertainty influences dose planning objectives and treatment outcome predictions.A framework was developed where the dose mapping can be associated with a variable known uncertainty to simulate the DIR uncertainties in a clinical workflow. The framework enabled us to study the dependence of dose planning metrics, and the predicted treatment outcome, on the DIR uncertainty. The additional planning margin needed to compensate for the dose mapping uncertainties can also be determined. We applied the simulation framework to a hypofractionated proton treatment of the prostate using two different scanning beam spot sizes to also study the dose mapping sensitivity to penumbra widths. The planning parameter most sensitive to the DIR uncertainty was found to be the target D95. We found that the registration mean absolute error needs to be ≤0.20 cm to obtain an uncertainty better than 3% of the calculated D95 for intermediate sized penumbras. Use of larger margins in constructing PTV from CTV relaxed the registration uncertainty requirements to the cost of increased dose burdens to the surrounding organs at risk. The DIR uncertainty requirements should be considered in an adaptive radiotherapy workflow since this uncertainty can have significant impact on the accumulated dose. The simulation framework enabled quantification of the accuracy requirement for DIR algorithms to provide satisfactory clinical accuracy in the accumulated dose.

  7. Treatment of Solitary Painful Osseous Metastases with Radiotherapy, Cryoablation or Combined Therapy: Propensity Matching Analysis in 175 Patients

    PubMed Central

    Zugaro, Luigi; Bonfili, Pierluigi; Gregori, Lorenzo; Franzese, Pietro; Marampon, Francesco; Vittorini, Francesca; Moro, Roberto; Tombolini, Vincenzo; Di Cesare, Ernesto; Masciocchi, Carlo

    2015-01-01

    Purpose aim of this study was to identify outcomes in pain relief and quality of life in patients with a solitary painful osseous metastasis treated by radiotherapy, cryoablation or the combination using a propensity score matching study design. Materials and Methods 175 patients with painful bone metastases were included in the study. Twenty-five of them underwent a radiation course (20 Gy in five daily fractions) 15 days after the cryoablation. These subjects were retrospectively matched by propensity analysis with a group of subjects treated by radiotherapy (125 subjects) and with a group treated byCryoablation (25 subjects). The pain relief in terms of complete response, rate of subjects requiring analgesics after treatments and the changes in self-rated quality of life were measured. Informed consent was obtained from the subject and the study was approved by the local Ethical Committee. Results An higher proportion of subjects treated by cryoablation (32%) or cryoablation followed by RT (72%;) experienced a complete response compared with patients treated by radiotherapy alone (11.2%). After Bonferroni correction strategy, the addition of radiotherapy to cryoablation significantly improved the rate of complete response compared with cryoablation alone (p = 0.011) and this paralleled with an improved self-rated quality of life. Seventeen subjects (13.6%) of patients in the radiotherapy group, 9 (36%) in the cryoablation group, and 19 (76)% in the cryoablation- radiotherapy group did not require narcotic medications. Conclusions The addition of radiotherapy to cryoablation favorably impacts on perceived pain, with a favorable toxicity profile. However, our data should be interpreted with caution and could serve as a framework around which to design future trials. PMID:26103516

  8. Patient-specific dosimetric endpoints based treatment plan quality control in radiotherapy.

    PubMed

    Song, Ting; Staub, David; Chen, Mingli; Lu, Weiguo; Tian, Zhen; Jia, Xun; Li, Yongbao; Zhou, Linghong; Jiang, Steve B; Gu, Xuejun

    2015-11-07

    In intensity modulated radiotherapy (IMRT), the optimal plan for each patient is specific due to unique patient anatomy. To achieve such a plan, patient-specific dosimetric goals reflecting each patient's unique anatomy should be defined and adopted in the treatment planning procedure for plan quality control. This study is to develop such a personalized treatment plan quality control tool by predicting patient-specific dosimetric endpoints (DEs). The incorporation of patient specific DEs is realized by a multi-OAR geometry-dosimetry model, capable of predicting optimal DEs based on the individual patient's geometry. The overall quality of a treatment plan is then judged with a numerical treatment plan quality indicator and characterized as optimal or suboptimal. Taking advantage of clinically available prostate volumetric modulated arc therapy (VMAT) treatment plans, we built and evaluated our proposed plan quality control tool. Using our developed tool, six of twenty evaluated plans were identified as sub-optimal plans. After plan re-optimization, these suboptimal plans achieved better OAR dose sparing without sacrificing the PTV coverage, and the dosimetric endpoints of the re-optimized plans agreed well with the model predicted values, which validate the predictability of the proposed tool. In conclusion, the developed tool is able to accurately predict optimally achievable DEs of multiple OARs, identify suboptimal plans, and guide plan optimization. It is a useful tool for achieving patient-specific treatment plan quality control.

  9. Measuring dose from radiotherapy treatments in the vicinity of a cardiac pacemaker.

    PubMed

    Peet, Samuel C; Wilks, Rachael; Kairn, Tanya; Crowe, Scott B

    2016-12-01

    This study investigated the dose absorbed by tissues surrounding artificial cardiac pacemakers during external beam radiotherapy procedures. The usefulness of out-of-field reference data, treatment planning systems, and skin dose measurements to estimate the dose in the vicinity of a pacemaker was also examined. Measurements were performed by installing a pacemaker onto an anthropomorphic phantom, and using radiochromic film and optically stimulated luminescence dosimeters to measure the dose in the vicinity of the device during the delivery of square fields and clinical treatment plans. It was found that the dose delivered in the vicinity of the cardiac device was unevenly distributed both laterally and anteroposteriorly. As the device was moved distally from the square field, the dose dropped exponentially, in line with out-of-field reference data in the literature. Treatment planning systems were found to substantially underestimate the dose for volumetric modulated arc therapy, helical tomotherapy, and 3D conformal treatments. The skin dose was observed to be either greater or lesser than the dose received at the depth of the device, depending on the treatment site, and so care should be if skin dose measurements are to be used to estimate the dose to a pacemaker. Square field reference data may be used as an upper estimate of absorbed dose per monitor unit in the vicinity of a cardiac device for complex treatments involving multiple gantry angles. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  10. Radiobiological assessment of non-standard and novel radiotherapy treatments using the linear-quadratic model.

    PubMed

    Dale, R G

    1993-01-01

    The linear-quadratic (LQ) model is useful in the radiobiological assessment of a wide variety of radiotherapy treatment techniques, not being confined to analysis of fractionated treatments alone. The model uses parameters that must be separately specified for tumours and dose-limiting normal tissues, and may therefore be used to help identify treatments that are most likely to maximise tumour cell kill while minimising the risk of severe normal-tissue damage. Additionally, the model is capable of making tentative allowance for the tumour repopulation that can occur during extended treatments. Intercomparisons between different types of treatment are made through the concept of the Extrapolated Response Dose (ERD). The ERD is calculated for each critical tissue and takes account of both the radiobiological parameters and the dose/time pattern of radiation delivery. Known tolerance doses for specified organs may be expressed as an ERDtolerance value, and, if a proposed 'new' treatment is to be successful, its associated ERD value must not exceed ERDtolerance. Examples of this procedure are given in this paper. It is particularly important that medical physicists fully appreciate the scope and limitations of LQ equations, as the analysis of radiobiology problems using the model often requires a degree of mathematical understanding that clinicians may not possess.

  11. Patient-specific dosimetric endpoints based treatment plan quality control in radiotherapy

    NASA Astrophysics Data System (ADS)

    Song, Ting; Staub, David; Chen, Mingli; Lu, Weiguo; Tian, Zhen; Jia, Xun; Li, Yongbao; Zhou, Linghong; Jiang, Steve B.; Gu, Xuejun

    2015-11-01

    In intensity modulated radiotherapy (IMRT), the optimal plan for each patient is specific due to unique patient anatomy. To achieve such a plan, patient-specific dosimetric goals reflecting each patient’s unique anatomy should be defined and adopted in the treatment planning procedure for plan quality control. This study is to develop such a personalized treatment plan quality control tool by predicting patient-specific dosimetric endpoints (DEs). The incorporation of patient specific DEs is realized by a multi-OAR geometry-dosimetry model, capable of predicting optimal DEs based on the individual patient’s geometry. The overall quality of a treatment plan is then judged with a numerical treatment plan quality indicator and characterized as optimal or suboptimal. Taking advantage of clinically available prostate volumetric modulated arc therapy (VMAT) treatment plans, we built and evaluated our proposed plan quality control tool. Using our developed tool, six of twenty evaluated plans were identified as sub-optimal plans. After plan re-optimization, these suboptimal plans achieved better OAR dose sparing without sacrificing the PTV coverage, and the dosimetric endpoints of the re-optimized plans agreed well with the model predicted values, which validate the predictability of the proposed tool. In conclusion, the developed tool is able to accurately predict optimally achievable DEs of multiple OARs, identify suboptimal plans, and guide plan optimization. It is a useful tool for achieving patient-specific treatment plan quality control.

  12. Powder treatment process

    DOEpatents

    Weyand, John D.

    1988-01-01

    (1) A process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder.

  13. Powder treatment process

    DOEpatents

    Weyand, J.D.

    1988-02-09

    Disclosed are: (1) a process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder. 2 figs.

  14. Serum levels of selenium in patients with breast cancer before and after treatment of external beam radiotherapy.

    PubMed

    Franca, C A S; Nogueira, C R; Ramalho, A; Carvalho, A C P; Vieira, S L; Penna, A B R C

    2011-05-01

    To evaluate the influence of radiotherapy on the selenium serum levels of breast cancer patients. This prospective study includes 209 breast cancer patients treated by external beam radiotherapy from December 2007 until August 2008. Plasma selenium concentrations were determined before and at the end of the radiotherapeutic treatment. Age, clinical stage, prior chemotherapy, body mass index (BMI) and personal habits (smoking and alcoholism) were recorded for each patient. The mean age was 61 years; the mean BMI was 28.7. One hundred and seventy-four patients (83.3%) were nonsmokers. One hundred and eighty-nine patients (90.4%) showed no drinking habits and 110 (52.6%) have no prior chemotherapy. Sixty patients (28.7%) were in clinical stage I, 141 (67.5%) in clinical stage II and 8 (3.8%) in clinical stage III. At the beginning of radiotherapy, the mean selenium value for all patients was 86.4 μg/l and after radiation this value dropped to 47.8 μg/l. Multivariate analysis showed statistically significant difference in the plasma selenium concentration before and after radiotherapy for age (P > 0.001), BMI (P > 0.001), smoking (P > 0.001), alcoholism (P > 0.001), chemotherapy (P > 0.001) and clinical stage (P > 0.001). Significant reduction in plasma levels of selenium is recorded in patients undergoing radiotherapy, suggesting attention to the nutritional status of this micronutrient and other antioxidant agents.

  15. A technique using {sup 99m}Tc-mebrofenin SPECT for radiotherapy treatment planning for liver cancers or metastases

    SciTech Connect

    Shen, Sui; Jacob, Rojymon; Bender, Luvenia W.; Duan, Jun; Spencer, Sharon A.

    2014-04-01

    Radiotherapy or stereotactic body radiosurgery (SBRT) requires a sufficient functional liver volume to tolerate the treatment. The current study extended the work of de Graaf et al. (2010) [3] on the use of {sup 99m}Tc-mebrofenin imaging for presurgery planning to radiotherapy planning for liver cancer or metastases. Patient was immobilized and imaged in an identical position on a single-photon emission computed tomography/computed tomography (SPECT-CT) system and a radiotherapy simulation CT system. {sup 99m}Tc-mebrofenin SPECT was registered to the planning CT through image registration of noncontrast CT from SPECT-CT system to the radiotherapy planning CT. The voxels with higher uptake of {sup 99m}Tc-mebrofenin were transferred to the planning CT as an avoidance structure in optimizing a 2-arc RapidArc plan for SBRT delivery. Excellent dose coverage to the target and sparing of the healthy remnant liver volume was achieved. This report illustrated a procedure for the use of {sup 99m}Tc-mebrofenin SPECT for optimizing radiotherapy for liver cancers and metastases.

  16. The hidden experience of radiotherapy to the head and neck: a qualitative study of patients after completion of treatment.

    PubMed

    Wells, M

    1998-10-01

    Only a small proportion of cancer patients undergo radical radiotherapy to the head and neck, but their needs are particularly complex. Radiation reactions often exacerbate existing functional difficulties and may severely limit 'normal' life. Few existing studies examine what happens when radiotherapy is over, yet this is the time when reactions are at their peak and day to day links with the hospital are severed. This naturalistic inquiry uses a combination of methods to explore the experiences of 12 patients after completion of radiotherapy to the head and neck. The impact of radiotherapy and the profound disruption to daily life is shown by the uncertainty and unpredictability of symptoms, the waiting, ambiguity and loss of self integrity which occurs throughout this time. Despite considerable physical and emotional trauma, patients showed remarkable resilience and a profound reluctance to ask for help. The findings demand that we re-examine our styles of communication, and consider how well we give information and listen to what is really happening. It is imperative that we provide greater consistency and continuity of care during radiotherapy, recognize the impact of the whole experience and respond to the post-treatment needs of this unique patient group.

  17. A technique using 99mTc-mebrofenin SPECT for radiotherapy treatment planning for liver cancers or metastases.

    PubMed

    Shen, Sui; Jacob, Rojymon; Bender, Luvenia W; Duan, Jun; Spencer, Sharon A

    2014-01-01

    Radiotherapy or stereotactic body radiosurgery (SBRT) requires a sufficient functional liver volume to tolerate the treatment. The current study extended the work of de Graaf et al. (2010) [3] on the use of (99m)Tc-mebrofenin imaging for presurgery planning to radiotherapy planning for liver cancer or metastases. Patient was immobilized and imaged in an identical position on a single-photon emission computed tomography/computed tomography (SPECT-CT) system and a radiotherapy simulation CT system. (99m)Tc-mebrofenin SPECT was registered to the planning CT through image registration of noncontrast CT from SPECT-CT system to the radiotherapy planning CT. The voxels with higher uptake of (99m)Tc-mebrofenin were transferred to the planning CT as an avoidance structure in optimizing a 2-arc RapidArc plan for SBRT delivery. Excellent dose coverage to the target and sparing of the healthy remnant liver volume was achieved. This report illustrated a procedure for the use of (99m)Tc-mebrofenin SPECT for optimizing radiotherapy for liver cancers and metastases. Copyright © 2014 American Association of Medical Dosimetrists. All rights reserved.

  18. Correcting radiation survey data to account for increased leakage during intensity modulated radiotherapy treatments

    SciTech Connect

    Kairn, T.; Crowe, S. B.; Trapp, J. V.

    2013-11-15

    Purpose: Intensity modulated radiotherapy (IMRT) treatments require more beam-on time and produce more linac head leakage to deliver similar doses to conventional, unmodulated, radiotherapy treatments. It is necessary to take this increased leakage into account when evaluating the results of radiation surveys around bunkers that are, or will be, used for IMRT. The recommended procedure of applying a monitor-unit based workload correction factor to secondary barrier survey measurements, to account for this increased leakage when evaluating radiation survey measurements around IMRT bunkers, can lead to potentially costly overestimation of the required barrier thickness. This study aims to provide initial guidance on the validity of reducing the value of the correction factor when applied to different radiation barriers (primary barriers, doors, maze walls, and other walls) by evaluating three different bunker designs.Methods: Radiation survey measurements of primary, scattered, and leakage radiation were obtained at each of five survey points around each of three different radiotherapy bunkers and the contribution of leakage to the total measured radiation dose at each point was evaluated. Measurements at each survey point were made with the linac gantry set to 12 equidistant positions from 0° to 330°, to assess the effects of radiation beam direction on the results.Results: For all three bunker designs, less than 0.5% of dose measured at and alongside the primary barriers, less than 25% of the dose measured outside the bunker doors and up to 100% of the dose measured outside other secondary barriers was found to be caused by linac head leakage.Conclusions: Results of this study suggest that IMRT workload corrections are unnecessary, for survey measurements made at and alongside primary barriers. Use of reduced IMRT workload correction factors is recommended when evaluating survey measurements around a bunker door, provided that a subset of the measurements used in

  19. Correcting radiation survey data to account for increased leakage during intensity modulated radiotherapy treatments.

    PubMed

    Kairn, T; Crowe, S B; Trapp, J V

    2013-11-01

    Intensity modulated radiotherapy (IMRT) treatments require more beam-on time and produce more linac head leakage to deliver similar doses to conventional, unmodulated, radiotherapy treatments. It is necessary to take this increased leakage into account when evaluating the results of radiation surveys around bunkers that are, or will be, used for IMRT. The recommended procedure of applying a monitor-unit based workload correction factor to secondary barrier survey measurements, to account for this increased leakage when evaluating radiation survey measurements around IMRT bunkers, can lead to potentially costly overestimation of the required barrier thickness. This study aims to provide initial guidance on the validity of reducing the value of the correction factor when applied to different radiation barriers (primary barriers, doors, maze walls, and other walls) by evaluating three different bunker designs. Radiation survey measurements of primary, scattered, and leakage radiation were obtained at each of five survey points around each of three different radiotherapy bunkers and the contribution of leakage to the total measured radiation dose at each point was evaluated. Measurements at each survey point were made with the linac gantry set to 12 equidistant positions from 0° to 330°, to assess the effects of radiation beam direction on the results. For all three bunker designs, less than 0.5% of dose measured at and alongside the primary barriers, less than 25% of the dose measured outside the bunker doors and up to 100% of the dose measured outside other secondary barriers was found to be caused by linac head leakage. Results of this study suggest that IMRT workload corrections are unnecessary, for survey measurements made at and alongside primary barriers. Use of reduced IMRT workload correction factors is recommended when evaluating survey measurements around a bunker door, provided that a subset of the measurements used in this study are repeated for the

  20. Overview of recent advances in treatment planning for ion beam radiotherapy

    NASA Astrophysics Data System (ADS)

    Krämer, Michael; Scifoni, Emanuele; Schmitz, Frederike; Sokol, Olga; Durante, Marco

    2014-10-01

    To achieve practical calculations of dose delivery in ion beam radiotherapy, the physical models of beam propagation need to be properly implemented and supplemented by models describing the complex mechanisms of radiation damage in the biological tissues. TRiP98 is the first and most advanced treatment planning system for particles, in which physical and biological models have been incorporated to develop a clinically applicable tool for dose optimization and delivery. We report our recent advances in TRiP98 code development, in particular towards hypoxia-driven and multi-modal dose optimization. We also discuss the present needs and possible extensions of our models for which input from nanoscale physics is required. Contribution to the Topical Issue "Nano-scale Insights into Ion-beam Cancer Therapy", edited by Andrey V. Solov'yov, Nigel Mason, Paulo Limão-Vieira and Malgorzata Smialek-Telega.

  1. The role of radiotherapy in the treatment of bile duct carcinoma.

    PubMed

    Veeze-Kuijpers, B; Meerwaldt, J H; Lameris, J S; van Blankenstein, M; van Putten, W L; Terpstra, O T

    1990-01-01

    Forty-two patients with irresectable bile duct carcinoma (n = 31) or with microscopic evidence of tumor rest after aggressive surgery for bile duct carcinoma (n = 11) were given radiotherapy consisting intentionally of external-beam therapy and intraluminal 192Iridium (192Ir) wire application(s) following bile drainage procedures. The treatment was well tolerated; complications were mainly infectious and related to the success of the drainage. A median survival of 10 months was achieved for the group as a whole. Patients treated following microscopically incomplete resection survived longer than patients with an irresectable tumor (15 vs 8 months median survival, p = 0.06). Gross lymph node involvement also proved to be a prognostic factor.

  2. The role of radiotherapy in the treatment of bile duct carcinoma

    SciTech Connect

    Veeze-Kuijpers, B.; Meerwaldt, J.H.; Lameris, J.S.; van Blankenstein, M.; van Putten, W.L.; Terpstra, O.T. )

    1990-01-01

    Forty-two patients with irresectable bile duct carcinoma (n = 31) or with microscopic evidence of tumor rest after aggressive surgery for bile duct carcinoma (n = 11) were given radiotherapy consisting intentionally of external-beam therapy and intraluminal 192Iridium ({sup 192}Ir) wire application(s) following bile drainage procedures. The treatment was well tolerated; complications were mainly infectious and related to the success of the drainage. A median survival of 10 months was achieved for the group as a whole. Patients treated following microscopically incomplete resection survived longer than patients with an irresectable tumor (15 vs 8 months median survival, p = 0.06). Gross lymph node involvement also proved to be a prognostic factor.

  3. Benefit of Carbon Ion Radiotherapy in the Treatment of Radio-resistant Tumors

    SciTech Connect

    Kamada, Tadashi; Tsujii, Hirohiko; Tsuji, Hiroshi; Yanagi, Tsuyoshi; Imai, Reiko; Mizoe, Jun-etsu; Miyamoto, Tadaaki; Kato, Hirotoshi; Yamada, Shigeru; Kato, Shingo; Yoshikawa, Kyousan; Kandatsu, Susumu

    2003-08-26

    The Heavy Ion Medical Accelerator in Chiba (HIMAC) is the world's first heavy ion accelerator complex dedicated to medical use in a hospital environment. Heavy ions have superior depth-dose distribution and greater cell-killing ability. In June 1994, clinical research for the treatment of cancer was begun using carbon ions generated by HIMAC. Until August 2002, a total of 1,297 patients were enrolled in clinical trials. Most of the patients had locally advanced and/or medically inoperable tumors. Tumors radio-resistant and/or located near critical organs were also included. The clinical trials revealed that carbon ion radiotherapy provided definite local control and offered a survival advantage without unacceptable morbidity in a variety of tumors that were hard to cure by other modalities.

  4. Speedup of lexicographic optimization by superiorization and its applications to cancer radiotherapy treatment

    NASA Astrophysics Data System (ADS)

    Bonacker, Esther; Gibali, Aviv; Küfer, Karl-Heinz; Süss, Philipp

    2017-04-01

    Multicriteria optimization problems occur in many real life applications, for example in cancer radiotherapy treatment and in particular in intensity modulated radiation therapy (IMRT). In this work we focus on optimization problems with multiple objectives that are ranked according to their importance. We solve these problems numerically by combining lexicographic optimization with our recently proposed level set scheme, which yields a sequence of auxiliary convex feasibility problems; solved here via projection methods. The projection enables us to combine the newly introduced superiorization methodology with multicriteria optimization methods to speed up computation while guaranteeing convergence of the optimization. We demonstrate our scheme with a simple 2D academic example (used in the literature) and also present results from calculations on four real head neck cases in IMRT (Radiation Oncology of the Ludwig-Maximilians University, Munich, Germany) for two different choices of superiorization parameter sets suited to yield fast convergence for each case individually or robust behavior for all four cases.

  5. Impact of Radiation in Critical Organs in Radiotherapy Treatment of Breast and Lung Cancers

    NASA Astrophysics Data System (ADS)

    Pyakuryal, Anil; Chen, Chiu-Hao; Dhungana, Sudarshan

    2010-02-01

    Various 3D conformal radiotherapy (3DCRT) techniques are commonly used in the treatment of cancerous tumors at appropriate prescription doses (PDs). The purpose of this study was to analyze the impact of radiation in heart and lungs in left breast and left lung cancer patients treated using 3DCRT techniques. Treatment plans for the eight breast cancer patients (n=8), eight lung cancer patients at early stage (m=8), and eight lung cancer patients at stage II and III (k=8) were evaluated. Relative complication probabilities (RCPs) for the irradiated organs were computed from the plans using HART [Med. Phys. 36, p.2547 (2009)] program at PD. The RCPs were found to be (i) 2.3% (n=8, PD=56 Gy), 6.4% (m=8, PD=30.7 Gy), and 16.7% (k=8, PD=54.8 Gy) for the heart, (ii) 1% (n=6, PD=58.4 Gy) for the left lung, and (iii) 7% (m=6, PD=31 Gy) and 5.3% (k=8, PD=54.8 Gy) for the whole lung. Homogeneous target coverage and improved dose conformality were the major advantages in the treatment of breast cancer. Therefore, simple 3DCRT based whole-breast irradiation and partial lung treatment techniques can offer promising results while adequately sparing the organs in the treatment of breast and lung cancers. )

  6. The probability of correct target dosage: dose-population histograms for deriving treatment margins in radiotherapy.

    PubMed

    van Herk, M; Remeijer, P; Rasch, C; Lebesque, J V

    2000-07-01

    To provide an analytical description of the effect of random and systematic geometrical deviations on the target dose in radiotherapy and to derive margin rules. The cumulative dose distribution delivered to the clinical target volume (CTV) is expressed analytically. Geometrical deviations are separated into treatment execution (random) and treatment preparation (systematic) variations. The analysis relates each possible preparation (systematic) error to the dose distribution over the CTV and allows computation of the probability distribution of, for instance, the minimum dose delivered to the CTV. The probability distributions of the cumulative dose over a population of patients are called dose-population histograms in short. Large execution (random) variations lead to CTV underdosage for a large number of patients, while the same level of preparation (systematic) errors leads to a much larger underdosage for some of the patients. A single point on the histogram gives a simple "margin recipe." For example, to ensure a minimum dose to the CTV of 95% for 90% of the patients, a margin between CTV and planning target volume (PTV) is required of 2.5 times the total standard deviation (SD) of preparation (systematic) errors (Sigma) plus 1.64 times the total SD of execution (random) errors (sigma') combined with the penumbra width, minus 1.64 times the SD describing the penumbra width (sigma(p)). For a sigma(p) of 3.2 mm, this recipe can be simplified to 2.5 Sigma + 0.7 sigma'. Because this margin excludes rotational errors and shape deviations, it must be considered as a lower limit for safe radiotherapy. Dose-population histograms provide insight into the effects of geometrical deviations on a population of patients. Using a dose-probability based approach, simple algorithms for choosing margins were derived.

  7. Malignant obstructive jaundice: treatment with external-beam and intracavitary radiotherapy.

    PubMed

    Johnson, D W; Safai, C; Goffinet, D R

    1985-02-01

    Eleven patients with obstructive jaundice from unresectable cholangiocarcinoma, metastatic porta hepatis adenopathy, or direct compression from a pancreatic malignancy were treated at the Stanford University Medical Center from 1978-1983 with an external drainage procedure followed by high-dose external-beam radiotherapy and by an intracavitary boost to the site of obstruction with Iridium192 (Ir192). A median dose of 5000 cGy was delivered with 4-6 Mv photons to the tumor bed and regional lymphatics in 9 patients, 1 patient received 2100 cGy to the liver in accelerated fractions because of extensive intrahepatic disease, and 1 patient received 7000 "equivalent" cGy to his pancreatic tumor bed and regional lymphatics with neon heavy particles. An Ir192 wire source later delivered a 3100-10,647 cGy boost to the site of biliary obstruction in each patient, for a mean combined dose of 10,202 cGy to a point 5 mm from the line source. Few acute complications were noted, but 3/11 patients (27%) subsequently developed upper gastrointestinal bleeding from duodenitis or frank duodenal ulceration 4 weeks, 4 months, and 7.5 months following treatment. Eight patients died--5 with local recurrence +/- distant metastasis, 2 with sepsis, and 1 with widespread systemic metastasis. Autopsies revealed no evidence of biliary tree obstruction in 3/3 patients. Mean survival time from initial laparotomy and bypass was 16.1 months, and from radiotherapy completion was 8.3 months. Evolution of radiation treatment techniques for biliary obstruction in the literature is reviewed. High-dose external-beam therapy followed by high-dose Ir192 intracavitary boost is well tolerated and provides significant palliation. Survival of these aggressively managed patients approaches that of patients with primarily resectable tumors.

  8. Outcomes of stereotactic body radiotherapy (SBRT) treatment of multiple synchronous and recurrent lung nodules.

    PubMed

    Owen, Dawn; Olivier, Kenneth R; Mayo, Charles S; Miller, Robert C; Nelson, Kathryn; Bauer, Heather; Brown, Paul D; Park, Sean S; Ma, Daniel J; Garces, Yolanda I

    2015-02-18

    Stereotactic body radiotherapy (SBRT) is evolving into a standard of care for unresectable lung nodules. Local control has been shown to be in excess of 90% at 3 years. However, some patients present with synchronous lung nodules in the ipsilateral or contralateral lobe or metasynchronous disease. In these cases, patients may receive multiple courses of lung SBRT or a single course for synchronous nodules. The toxicity of such treatment is currently unknown. Between 2006 and 2012, 63 subjects with 128 metasynchronous and synchronous lung nodules were treated at the Mayo Clinic with SBRT. Demographic patient data and dosimetric data regarding SBRT treatments were collected. Acute toxicity (defined as toxicity < 90 days) and late toxicity (defined as toxicity > = 90 days) were reported and graded as per standardized CTCAE 4.0 criteria. Local control, progression free survival and overall survival were also described. The median age of patients treated was 73 years. Sixty five percent were primary or recurrent lung cancers with the remainder metastatic lung nodules of varying histologies. Of 63 patients, 18 had prior high dose external beam radiation to the mediastinum or chest. Dose and fractionation varied but the most common prescriptions were 48 Gy/4 fractions, 54 Gy/3 fractions, and 50 Gy/5 fractions. Only 6 patients demonstrated local recurrence. With a median follow up of 12.6 months, median SBRT specific overall survival and progression free survival were 35.7 months and 10.7 months respectively. Fifty one percent (32/63 patients) experienced acute toxicity, predominantly grade 1 and 2 fatigue. One patient developed acute grade 3 radiation pneumonitis at 75 days. Forty six percent (29/63 patients) developed late effects. Most were grade 1 dyspnea. There was one patient with grade 5 pneumonitis. Multiple courses of SBRT and SBRT delivery after external beam radiotherapy appear to be feasible and safe. Most toxicity was grade 1 and 2 but the risk was

  9. Successful Treatment of Tumor-Induced Osteomalacia due to an Intracranial Tumor by Fractionated Stereotactic Radiotherapy

    PubMed Central

    Trepp-Carrasco, Alejandro G.; Thompson, Robert; Recker, Robert R.; Chong, William H.; Collins, Michael T.

    2013-01-01

    Context: Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome, characterized by tumor secretion of fibroblast growth factor-23 (FGF23) causing hypophosphatemia due to renal phosphate wasting. TIO is usually caused by small, benign, difficult-to-localize, mesenchymal tumors. Although surgery with wide excision of tumor borders is considered the “gold standard” for definitive therapy, it can be associated with considerable morbidity depending on the location. To date, radiation therapy has not been considered as an effective treatment modality in TIO. Objective: A 67-year-old female presented with multiple nontraumatic fractures, progressive bone pain, and muscle weakness for 4 years. She was found to have biochemical evidence of urinary phosphate wasting with low serum phosphorus, low-normal serum calcium, normal 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, and high serum FGF23 levels. TIO was diagnosed. Selective venous sampling for FGF23 confirmed that a 1.7-cm left frontal mass, radiographically similar to a meningioma, was the causative tumor. She declined surgery due to fear of complications and instead underwent fractionated stereotactic radiotherapy for 6 weeks. Results: In less than 4 years after radiation therapy, she was successfully weaned off phosphorus and calcitriol, starting from 2 g of oral phosphorus daily and 1 μg of calcitriol daily. Her symptoms have resolved, and she has not had any new fractures. Conclusions: Stereotactic radiotherapy was an effective treatment modality for TIO in our patient. Fractionated stereotactic radiation therapy represents an alternative to surgery for patients with TIO who are not surgical candidates or who decline surgery. PMID:24014621

  10. Successful treatment of tumor-induced osteomalacia due to an intracranial tumor by fractionated stereotactic radiotherapy.

    PubMed

    Tarasova, Valentina D; Trepp-Carrasco, Alejandro G; Thompson, Robert; Recker, Robert R; Chong, William H; Collins, Michael T; Armas, Laura A G

    2013-11-01

    Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome, characterized by tumor secretion of fibroblast growth factor-23 (FGF23) causing hypophosphatemia due to renal phosphate wasting. TIO is usually caused by small, benign, difficult-to-localize, mesenchymal tumors. Although surgery with wide excision of tumor borders is considered the "gold standard" for definitive therapy, it can be associated with considerable morbidity depending on the location. To date, radiation therapy has not been considered as an effective treatment modality in TIO. A 67-year-old female presented with multiple nontraumatic fractures, progressive bone pain, and muscle weakness for 4 years. She was found to have biochemical evidence of urinary phosphate wasting with low serum phosphorus, low-normal serum calcium, normal 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, and high serum FGF23 levels. TIO was diagnosed. Selective venous sampling for FGF23 confirmed that a 1.7-cm left frontal mass, radiographically similar to a meningioma, was the causative tumor. She declined surgery due to fear of complications and instead underwent fractionated stereotactic radiotherapy for 6 weeks. In less than 4 years after radiation therapy, she was successfully weaned off phosphorus and calcitriol, starting from 2 g of oral phosphorus daily and 1 μg of calcitriol daily. Her symptoms have resolved, and she has not had any new fractures. Stereotactic radiotherapy was an effective treatment modality for TIO in our patient. Fractionated stereotactic radiation therapy represents an alternative to surgery for patients with TIO who are not surgical candidates or who decline surgery.

  11. Optimized PET imaging for 4D treatment planning in radiotherapy: the virtual 4D PET strategy.

    PubMed

    Gianoli, Chiara; Riboldi, Marco; Fontana, Giulia; Giri, Maria G; Grigolato, Daniela; Ferdeghini, Marco; Cavedon, Carlo; Baroni, Guido

    2015-02-01

    The purpose of the study is to evaluate the performance of a novel strategy, referred to as "virtual 4D PET", aiming at the optimization of hybrid 4D CT-PET scan for radiotherapy treatment planning. The virtual 4D PET strategy applies 4D CT motion modeling to avoid time-resolved PET image acquisition. This leads to a reduction of radioactive tracer administered to the patient and to a total acquisition time comparable to free-breathing PET studies. The proposed method exploits a motion model derived from 4D CT, which is applied to the free-breathing PET to recover respiratory motion and motion blur. The free-breathing PET is warped according to the motion model, in order to generate the virtual 4D PET. The virtual 4D PET strategy was tested on images obtained from a 4D computational anthropomorphic phantom. The performance was compared to conventional motion compensated 4D PET. Tests were also carried out on clinical 4D CT-PET scans coming from seven lung and liver cancer patients. The virtual 4D PET strategy was able to recover lesion motion, with comparable performance with respect to the motion compensated 4D PET. The compensation of the activity blurring due to motion was successfully achieved in terms of spill out removal. Specific limitations were highlighted in terms of partial volume compensation. Results on clinical 4D CT-PET scans confirmed the efficacy in 4D PET count statistics optimization, as equal to the free-breathing PET, and recovery of lesion motion. Compared to conventional motion compensation strategies that explicitly require 4D PET imaging, the virtual 4D PET strategy reduces clinical workload and computational costs, resulting in significant advantages for radiotherapy treatment planning.

  12. The UK Standardisation of Breast Radiotherapy (START) trials of radiotherapy hypofractionation for treatment of early breast cancer: 10-year follow-up results of two randomised controlled trials.

    PubMed

    Haviland, Joanne S; Owen, J Roger; Dewar, John A; Agrawal, Rajiv K; Barrett, Jane; Barrett-Lee, Peter J; Dobbs, H Jane; Hopwood, Penelope; Lawton, Pat A; Magee, Brian J; Mills, Judith; Simmons, Sandra; Sydenham, Mark A; Venables, Karen; Bliss, Judith M; Yarnold, John R

    2013-10-01

    5-year results of the UK Standardisation of Breast Radiotherapy (START) trials suggested that lower total doses of radiotherapy delivered in fewer, larger doses (fractions) are at least as safe and effective as the historical standard regimen (50 Gy in 25 fractions) for women after primary surgery for early breast cancer. In this prespecified analysis, we report the 10-year follow-up of the START trials testing 13 fraction and 15 fraction regimens. From 1999 to 2002, women with completely excised invasive breast cancer (pT1-3a, pN0-1, M0) were enrolled from 35 UK radiotherapy centres. Patients were randomly assigned to a treatment regimen after primary surgery followed by chemotherapy and endocrine treatment (where prescribed). Randomisation was computer-generated and stratified by centre, type of primary surgery (breast-conservation surgery or mastectomy), and tumour bed boost radiotherapy. In START-A, a regimen of 50 Gy in 25 fractions over 5 weeks was compared with 41·6 Gy or 39 Gy in 13 fractions over 5 weeks. In START-B, a regimen of 50 Gy in 25 fractions over 5 weeks was compared with 40 Gy in 15 fractions over 3 weeks. Eligibility criteria included age older than 18 years and no immediate surgical reconstruction. Primary endpoints were local-regional tumour relapse and late normal tissue effects. Analysis was by intention to treat. Follow-up data are still being collected. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN59368779. START-A enrolled 2236 women. Median follow-up was 9·3 years (IQR 8·0-10·0), after which 139 local-regional relapses had occurred. 10-year rates of local-regional relapse did not differ significantly between the 41·6 Gy and 50 Gy regimen groups (6·3%, 95% CI 4·7-8·5 vs 7·4%, 5·5-10·0; hazard ratio [HR] 0·91, 95% CI 0·59-1·38; p=0·65) or the 39 Gy (8·8%, 95% CI 6·7-11·4) and 50 Gy regimen groups (HR 1·18, 95% CI 0·79-1·76; p=0·41). In START-A, moderate or marked

  13. An optimization method for importance factors and beam weights based on genetic algorithms for radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Wu, Xingen; Zhu, Yunping

    2001-04-01

    We propose a new method for selecting importance factors (for regions of interest like organs at risk) used to plan conformal radiotherapy. Importance factors, also known as weighting factors or penalty factors, are essential in determining the relative importance of multiple objectives or the penalty ratios of constraints incorporated into cost functions, especially in dealing with dose optimization in radiotherapy treatment planning. Researchers usually choose importance factors on the basis of a trial-and-error process to reach a balance between all the objectives. In this study, we used a genetic algorithm and adopted a real-number encoding method to represent both beam weights and importance factors in each chromosome. The algorithm starts by optimizing the beam weights for a fixed number of iterations then modifying the importance factors for another fixed number of iterations. During the first phase, the genetic operators, such as crossover and mutation, are carried out only on beam weights, and importance factors for each chromosome are not changed or `frozen'. In the second phase, the situation is reversed: the beam weights are `frozen' and the importance factors are changed after crossover and mutation. Through alternation of these two phases, both beam weights and importance factors are adjusted according to a fitness function that describes the conformity of dose distribution in planning target volume and dose-tolerance constraints in organs at risk. Those chromosomes with better fitness are passed into the next generation, showing that they have a better combination of beam weights and importance factors. Although the ranges of the importance factors should be set in advance by using this algorithm, it is much more convenient than selecting specific numbers for importance factors. Three clinical examples are presented and compared with manual plans to verify this method. Three-dimensional standard displays and dose-volume histograms are shown to

  14. Radiobiological comparison of two radiotherapy treatment techniques for high-risk prostate cancer

    PubMed Central

    Hernández, Trinitat García; González, Aurora Vicedo; Peidro, Jorge Pastor; Ferrando, Juan V. Roselló; González, Luis Brualla; Cabañero, Domingo Granero; Torrecilla, José López

    2013-01-01

    Background To make a radiobiological comparison, for high risk prostate cancer (T3a, PSA > 20 ng/ml or Gleason > 7) of two radiotherapy treatment techniques. One technique consists of a treatment in three phases of the pelvic nodes, vesicles and prostate using a conventional fractionation scheme of 2 Gy/fraction (SIMRT). The other technique consists of a treatment in two phases that gives simultaneously different dose levels in each phase, 2 Gy/fraction, 2.25 Gy/fraction and 2.5 Gy/fraction to the pelvic nodes, vesicles and prostate, respectively (SIBIMRT). Materials and methods The equivalent dose at fractionation of 2 Gy (EQD2), calculated using the linear quadratic model with α/βprostate = 1.5 Gy, was the same for both treatment strategies. For comparison the parameters employed were D95, mean dose and Tumour Control Probabilities for prostate PTV and D15, D25, D35, D50, mean dose and Normal Tissue Complication Probabilities for the rectum and bladder, with physical doses converted to EQD2. Parameters were obtained for α/βprostate = 1.5, 3 and 10 Gy and for α/βoar = 1, 2, 3, 4, 6 and 8. Results For prostate PTV, both treatment strategies are equivalent for α/βprostate = 1.5 Gy but for higher α/βprostate, EQD2 and TCP, decrease for the SIBIMRT technique. For the rectum and bladder when α/βoar ≤ 2 Gy, EQD2 and NTCP are lower for the SIMRT technique or equal in both techniques. For α/βoar ≥ 2–3 Gy, EQD2 and NTCP increase for the SIMRT treatment. Conclusions A comparison between two radiotherapy techniques is presented. The SIBIMRT technique reduces EQD2 and NTCP for α/βoar from 2 to 8 Gy. PMID:24416563

  15. Surgical spacer placement prior carbon ion radiotherapy (CIRT): an effective feasible strategy to improve the treatment for sacral chordoma.

    PubMed

    Lorenzo, Cobianchi; Andrea, Peloso; Barbara, Vischioni; Denis, Panizza; Rosaria, Fiore Maria; Piero, Fossati; Viviana, Vitolo; Alberto, Iannalfi; Mario, Ciocca; Brugnatelli, Silvia; Tommaso, Dominioni; Bugada, Dario; Marcello, Maestri; Mario, Alessiani; Francesca, Valvo; Roberto, Orecchia; Paolo, Dionigi

    2016-08-09

    Sacral chordoma (SC) is a neoplasm arising from residual notochordal cells degeneration. SC is difficult to manage mainly because of anatomic location and tendency to extensive spread. Carbon ion radiotherapy (CIRT) is highly precise to selectively deliver high biological effective dose to the tumor target sparing the anatomical structure on its path even if when SC is contiguous to the intestine, and a surgical spacer might be an advantageous tool to create a distance around the target volume allowing radical curative dose delivery with a safe dose gradient to the surrounding organs. This paper describes a double approach-open and hand-assisted laparoscopic-for a silicon spacer placement in patients affected by sacral chordoma undergoing carbon ion radiotherapy. Six consecutive patients have been enrolled for surgical spacer placement-open (three) or hand-assisted (three)-prior carbon ion radiotherapy treatment in order to increase efficacy of carbon ion radiotherapy minimizing its side effects. Results showed that silicon spacer placement for SC treatment is feasible both via laparoscopic and laparotomic approach. Its use might improve CIRT safety and thus efficacy for SC treatment.

  16. External beam radiotherapy as postoperative treatment of diffuse pigmented villonodular synovitis

    SciTech Connect

    Berger, Bernhard . E-mail: Bernhard.Berger@med.uni-tuebingen.de; Ganswindt, Ute; Bamberg, Michael; Hehr, Thomas

    2007-03-15

    Purpose: Diffuse pigmented villonodular synovitis is a rare proliferative disorder of synovial membranes with invasive and expansive growth patterns. Radical synovectomy is regarded as the treatment of choice. However, because of the high recurrence rates, additive treatment might be useful. Radiotherapy (RT) has been evaluated with positive results, but the optimal treatment schedules are vague. We have reviewed our experience with postoperative RT in cases of suspected or proven residual disease. Methods and Materials: Between December 1996 and January 2006, 7 diffuse pigmented villonodular synovitis patients underwent RT at our institution. The most common location was the knee joint (5 patients). All patients underwent radical surgery and were treated subsequently with 6-MV photon RT. The total doses applied were 30-50 Gy, depending on the resection status and estimated risk of relapse. For analysis, we retrospectively reviewed all patients in April 2006. Results: The mean follow-up time was 29 months (range, 3-112 months). RT had no acute adverse effects. At the assessment, no evidence was found of recurrent or persisting disease in any patient. Of the 7 patients, 6 reported asymptomatic limb function and excellent quality of life; 1 patient had persistent restriction of joint movement after repeated surgery. No radiotherapeutic late effects were seen. Conclusion: The results of our series have confirmed the efficacy and safety of postoperative RT for diffuse pigmented villonodular synovitis. Hence, this treatment should be considered for patients with suspected or proven residual disease.

  17. Ozone treatment for radiotherapy skin reactions: is there an evidence base for practice?

    PubMed

    Jordan, Liz; Beaver, Kinta; Foy, Sharon

    2002-12-01

    Clinical staff and researchers working together can do much to bridge the gap between research and practice. This paper reports on the practice of treating severe radiotherapy skin reactions with ozone therapy; a practice that has been in place for a number of years at a specialist oncology hospital in England and perceived to be beneficial in terms of wound healing and pain relief. A multidisciplinary team of clinical staff and researchers questioned the evidence base for this practice and a literature search revealed little support for the effectiveness of this treatment in this particular context. The views of patients receiving ozone therapy were sought and assessment forms were completed to gain objective information on the progress (or otherwise) of wound healing. While patients perceived the ozone treatment to be beneficial in terms of pain relief, it was impossible to isolate the impact of ozone alone as other preparations and treatments were also being given. Patient reports and nursing assessments did not support that ozone was effective at wound healing. A more formal evaluation of this treatment is being planned, supported by the shared governance initiative at the study site and a continued collaboration between clinical staff and researchers.

  18. Fractionated Stereotactic Radiotherapy Treatment of Cavernous Sinus Meningiomas: A Study of 100 Cases

    SciTech Connect

    Litre, Claude Fabien Colin, Philippe; Noudel, Remy; Peruzzi, Philippe; Bazin, Arnaud; Sherpereel, Bernard; Bernard, Marie Helene; Rousseaux, Pascal

    2009-07-15

    Purpose: We discuss our experiences with fractionated stereotactic radiotherapy (FSR) in the treatment of cavernous sinus meningiomas. Methods and Materials: From 1995 to 2006, we monitored 100 patients diagnosed with cavernous sinus meningiomas; 84 female and 16 male patients were included. The mean patient age was 56 years. The most common symptoms were a reduction in visual acuity (57%), diplopia (50%), exophthalmy (30%), and trigeminal neuralgia (34%). Surgery was initially performed on 26 patients. All patients were treated with FSR. A total of 45 Gy was administered to the lesion, with 5 fractions of 1.8 Gy completed each week. Patient treatment was performed using a Varian Clinac linear accelerator used for cranial treatments and a micro-multileaf collimator. Results: No side effects were reported. Mean follow-up period was 33 months, with 20% of patients undergoing follow-up evaluation of more than 4 years later. The tumor control rate at 3 years was 94%. Three patients required microsurgical intervention because FSR proved ineffective. In terms of functional symptoms, an 81% improvement was observed in patients suffering from exophthalmy, with 46% of these patients being restored to full health. A 52% improvement was observed in diplopia, together with a 67% improvement in visual acuity and a 50% improvement in type V neuropathy. Conclusions: FSR facilitates tumor control, either as an initial treatment option or in combination with microsurgery. In addition to being a safe procedure with few side effects, FSR offers the significant benefit of superior functional outcomes.

  19. SU-D-BRD-02: A Web-Based Image Processing and Plan Evaluation Platform (WIPPEP) for Future Cloud-Based Radiotherapy

    SciTech Connect

    Chai, X; Liu, L; Xing, L

    2014-06-01

    Purpose: Visualization and processing of medical images and radiation treatment plan evaluation have traditionally been constrained to local workstations with limited computation power and ability of data sharing and software update. We present a web-based image processing and planning evaluation platform (WIPPEP) for radiotherapy applications with high efficiency, ubiquitous web access, and real-time data sharing. Methods: This software platform consists of three parts: web server, image server and computation server. Each independent server communicates with each other through HTTP requests. The web server is the key component that provides visualizations and user interface through front-end web browsers and relay information to the backend to process user requests. The image server serves as a PACS system. The computation server performs the actual image processing and dose calculation. The web server backend is developed using Java Servlets and the frontend is developed using HTML5, Javascript, and jQuery. The image server is based on open source DCME4CHEE PACS system. The computation server can be written in any programming language as long as it can send/receive HTTP requests. Our computation server was implemented in Delphi, Python and PHP, which can process data directly or via a C++ program DLL. Results: This software platform is running on a 32-core CPU server virtually hosting the web server, image server, and computation servers separately. Users can visit our internal website with Chrome browser, select a specific patient, visualize image and RT structures belonging to this patient and perform image segmentation running Delphi computation server and Monte Carlo dose calculation on Python or PHP computation server. Conclusion: We have developed a webbased image processing and plan evaluation platform prototype for radiotherapy. This system has clearly demonstrated the feasibility of performing image processing and plan evaluation platform through a web

  20. Imaging in radiotherapy.

    PubMed

    Van den Berge, D L; De Ridder, M; Storme, G A

    2000-10-01

    Radiotherapy, more then any other treatment modality, relies heavily and often exclusively on medical imaging to determine the extent of disease and the spatial relation between target region and neighbouring healthy tissues. Radically new approaches to radiation delivery are inspired on CT scanning and treat patients in a slice-by-slice fashion using intensity modulated megavoltage fan beams. For quality assurance of complex 3-D dose distributions, MR based 3-D verificative dosimetry on irradiated phantoms has been described. As treatment delivery becomes increasingly refined, the need for accurate target definition increases as well and sophisticated imaging tools like image fusion and 3-D reconstruction are routinely used for treatment planning. While in the past patients were positioned on the treatment machines based exclusively on surface topography and the well-known skin marks, such approach is no longer sufficient for high-accuracy radiotherapy and special imaging tools like on-line portal imaging are used to verify and correct target positioning. Much of these applications rely on digital image processing, transmission and storage, and the development of standards, like DICOM and PACS have greatly contributed to these applications. Digital imaging plays an increasing role in many areas in radiotherapy and has been fundamental in new developments that have demonstrated impact on patient care.

  1. Radiotherapy treatment planning of prostate cancer using magnetic resonance imaging alone.

    PubMed

    Lee, Young K; Bollet, Marc; Charles-Edwards, Geoffrey; Flower, Maggie A; Leach, Martin O; McNair, Helen; Moore, Elizabeth; Rowbottom, Carl; Webb, Steve

    2003-02-01

    Accurate anatomical delineation of the gross tumour volume (GTV) is crucial for effective radiotherapy (RT) treatment of prostate cancers. Although reference to pelvic magnetic resonance (MR) for improved delineation of the prostate is a regular practice in some clinics, MR has not replaced CT due to its geometrical distortions and lack of electron-density information. The possibility and practicality of using MR only for RT treatment planning were studied. The addition of electron-density information to MR images for conformal radiotherapy (CRT) planning of the prostate was quantified by comparing dose distributions created on the homogeneous density- and bulk-density assigned images to original CT for four patients. To quantify the MR geometrical distortions measurements of a phantom imaged in CT (Siemens Somatom Plus 4) and FLASH 3D T1-weighted MR (1.5 T whole body Siemens Magnetom Vision) were compared. Dose statistics from CRT treatment plans made on CT and MR for five patient data were compared to determine if MR-only treatment plans can be made. The differences between dose-plans on bulk-density assigned images when compared to CT were less than 2% when water and bone values were assigned. Dose differences greater than 2% were observed when images of homogeneous-density assignment were compared to the CT. Phantom measurements showed that the distortions in the FLASH 3D T1-weighted MR averaged 2 mm in the volume of interest for prostate RT planning. For the CT and MR prostate planning study, doses delivered to the planning target volume (PTV) in CT and MR were always inside a 93-107% dose range normalised to the isocentre. Also, the doses to the organs-at-risk in the MR images were similar to the doses delivered to the volumes in the registered CT image when the organ volumes between the two images were similar. Negligible differences were observed in dose distribution between CRT plans using bone+water CT number bulk-assigned image and original CT. Also, the

  2. MO-B-BRB-00: Optimizing the Treatment Planning Process

    SciTech Connect

    2015-06-15

    The radiotherapy treatment planning process has evolved over the years with innovations in treatment planning, treatment delivery and imaging systems. Treatment modality and simulation technologies are also rapidly improving and affecting the planning process. For example, Image-guided-radiation-therapy has been widely adopted for patient setup, leading to margin reduction and isocenter repositioning after simulation. Stereotactic Body radiation therapy (SBRT) and Radiosurgery (SRS) have gradually become the standard of care for many treatment sites, which demand a higher throughput for the treatment plans even if the number of treatments per day remains the same. Finally, simulation, planning and treatment are traditionally sequential events. However, with emerging adaptive radiotherapy, they are becoming more tightly intertwined, leading to iterative processes. Enhanced efficiency of planning is therefore becoming more critical and poses serious challenge to the treatment planning process; Lean Six Sigma approaches are being utilized increasingly to balance the competing needs for speed and quality. In this symposium we will discuss the treatment planning process and illustrate effective techniques for managing workflow. Topics will include: Planning techniques: (a) beam placement, (b) dose optimization, (c) plan evaluation (d) export to RVS. Planning workflow: (a) import images, (b) Image fusion, (c) contouring, (d) plan approval (e) plan check (f) chart check, (g) sequential and iterative process Influence of upstream and downstream operations: (a) simulation, (b) immobilization, (c) motion management, (d) QA, (e) IGRT, (f) Treatment delivery, (g) SBRT/SRS (h) adaptive planning Reduction of delay between planning steps with Lean systems due to (a) communication, (b) limited resource, (b) contour, (c) plan approval, (d) treatment. Optimizing planning processes: (a) contour validation (b) consistent planning protocol, (c) protocol/template sharing, (d) semi

  3. Postoperative Radiotherapy for Maxillary Sinus Cancer: Long-Term Outcomes and Toxicities of Treatment

    SciTech Connect

    Bristol, Ian J. . E-mail: ijbristol@mdanderson.org; Ahamad, Anesa; Garden, Adam S.; Morrison, William H.; Hanna, Ehab Y.; Papadimitrakopoulou, Vassiliki A.; Rosenthal, David I.; Ang, K. Kian

    2007-07-01

    Purpose: To determine the effects of three changes in radiotherapy technique on the outcomes for patients irradiated postoperatively for maxillary sinus cancer. Methods and Materials: The data of 146 patients treated between 1969 and 2002 were reviewed. The patients were separated into two groups according to the date of treatment. Group 1 included 90 patients treated before 1991 and Group 2 included 56 patients treated after 1991, when the three changes were implemented. The outcomes were compared between the two groups. Results: No differences were found in the 5-year overall survival, recurrence-free survival, local control, nodal control, or distant metastasis rates between the two groups (51% vs. 62%, 51% vs. 57%, 76% vs. 70%, 82% vs. 83%, and 28% vs. 17% for Groups 1 and 2, respectively). The three changes were to increase the portals to cover the base of the skull in patients with perineural invasion, reducing their risk of local recurrence; the addition of elective neck irradiation in patients with squamous or undifferentiated histologic features, improving the nodal control, distant metastasis, and recurrence-free survival rates (64% vs. 93%, 20% vs. 3%, and 45% vs. 67%, respectively; p < 0.05 for all comparisons); and improving the dose distributions within the target volume, reducing the late Grade 3-4 complication rates (34% in Group 1 vs. 8% in Group 2, p = 0.014). Multivariate analysis revealed advancing age, the need for enucleation, and positive margins as independent predictors of worse overall survival. The need for enucleation also predicted for worse local control. Conclusion: The three changes in radiotherapy technique improved the outcomes for select patients as predicted. Despite these changes, little demonstrable overall improvement occurred in local control or survival for these patients and additional work must be done.

  4. The treatment of a large acoustic tumor with fractionated stereotactic radiotherapy.

    PubMed

    McClelland, Shearwood; Gerbi, Bruce J; Cho, Kwan H; Hall, Walter A

    2007-01-01

    The treatment of acoustic neuromas (AN) usually involves surgical excision or stereotactic radiosurgery. However, for large AN (mean diameter > 3 cm), stereotactic radiosurgery is rarely used, leaving patients with limited noninvasive treatment options. Recently, the use of fractionated stereotactic radiotherapy (FSRT) has been effective in treating small to medium-sized AN. We present a patient with a large AN treated with FSRT. The patient was a 43-year-old man presenting with imbalance, tinnitus, vertigo, and right-sided hearing decline associated with vomiting and hydrocephalus. Magnetic resonance (MR) imaging revealed a large, 3.8-cm, right cerebellopontine-angle tumor compressing the fourth ventricle. Following right frontal ventriculoperitoneal shunt placement, the patient underwent FSRT for treatment of the tumor. Using the Radionics X-Knife 4.0 3D treatment planning system, a total of 54 Gy was delivered in 1.8-Gy daily fractions with the prescription isodose line of 90%. Treatments were delivered using a dedicated Varian 6/100 linear accelerator, and head immobilization was achieved with the Gill-Thomas-Cosman relocatable stereotactic frame. The patient was subsequently evaluated with serial contrast-enhanced MR imaging. Following FSRT, local control (defined as the absence of tumor progression) was achieved, and treatment was well tolerated. There was no hearing-related, trigeminal, or facial-nerve morbidity following FSRT at 63-month follow-up. Treating a patient with a large AN with FSRT resulted in local tumor control, with no trigeminal nerve, facial nerve, or hearing-related morbidity. These results support FSRT as a potential noninvasive treatment modality for AN some would consider too large for single-fraction stereotactic radiosurgery (SRS).

  5. The adaptation of megavoltage cone beam CT for use in standard radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Thomas, T. Hannah Mary; Devakumar, D.; Purnima, S.; Ravindran, B. Paul

    2009-04-01

    Potential areas where megavoltage computed tomography (MVCT) could be used are second- and third-phase treatment planning in 3D conformal radiotherapy and IMRT, adaptive radiation therapy, single fraction palliative treatment and for the treatment of patients with metal prostheses. A feasibility study was done on using MV cone beam CT (CBCT) images generated by proprietary 3D reconstruction software based on the FDK algorithm for megavoltage treatment planning. The reconstructed images were converted to a DICOM file set. The pixel values of megavoltage cone beam computed tomography (MV CBCT) were rescaled to those of kV CT for use with a treatment planning system. A calibration phantom was designed and developed for verification of geometric accuracy and CT number calibration. The distance measured between two marker points on the CBCT image and the physical dimension on the phantom were in good agreement. Point dose verification for a 10 cm × 10 cm beam at a gantry angle of 0° and SAD of 100 cm were performed for a 6 MV beam for both kV and MV CBCT images. The point doses were found to vary between ±6.1% of the dose calculated from the kV CT image. The isodose curves for 6 MV for both kV CT and MV CBCT images were within 2% and 3 mm distance-to-agreement. A plan with three beams was performed on MV CBCT, simulating a treatment plan for cancer of the pituitary. The distribution obtained was compared with those corresponding to that obtained using the kV CT. This study has shown that treatment planning with MV cone beam CT images is feasible.

  6. FoCa: a modular treatment planning system for proton radiotherapy with research and educational purposes.

    PubMed

    Sánchez-Parcerisa, D; Kondrla, M; Shaindlin, A; Carabe, A

    2014-12-07

    FoCa is an in-house modular treatment planning system, developed entirely in MATLAB, which includes forward dose calculation of proton radiotherapy plans in both active and passive modalities as well as a generic optimization suite for inverse treatment planning. The software has a dual education and research purpose. From the educational point of view, it can be an invaluable teaching tool for educating medical physicists, showing the insights of a treatment planning system from a well-known and widely accessible software platform. From the research point of view, its current and potential uses range from the fast calculation of any physical, radiobiological or clinical quantity in a patient CT geometry, to the development of new treatment modalities not yet available in commercial treatment planning systems. The physical models in FoCa were compared with the commissioning data from our institution and show an excellent agreement in depth dose distributions and longitudinal and transversal fluence profiles for both passive scattering and active scanning modalities. 3D dose distributions in phantom and patient geometries were compared with a commercial treatment planning system, yielding a gamma-index pass rate of above 94% (using FoCa's most accurate algorithm) for all cases considered. Finally, the inverse treatment planning suite was used to produce the first prototype of intensity-modulated, passive-scattered proton therapy, using 13 passive scattering proton fields and multi-leaf modulation to produce a concave dose distribution on a cylindrical solid water phantom without any field-specific compensator.

  7. FoCa: a modular treatment planning system for proton radiotherapy with research and educational purposes

    NASA Astrophysics Data System (ADS)

    Sánchez-Parcerisa, D.; Kondrla, M.; Shaindlin, A.; Carabe, A.

    2014-12-01

    FoCa is an in-house modular treatment planning system, developed entirely in MATLAB, which includes forward dose calculation of proton radiotherapy plans in both active and passive modalities as well as a generic optimization suite for inverse treatment planning. The software has a dual education and research purpose. From the educational point of view, it can be an invaluable teaching tool for educating medical physicists, showing the insights of a treatment planning system from a well-known and widely accessible software platform. From the research point of view, its current and potential uses range from the fast calculation of any physical, radiobiological or clinical quantity in a patient CT geometry, to the development of new treatment modalities not yet available in commercial treatment planning systems. The physical models in FoCa were compared with the commissioning data from our institution and show an excellent agreement in depth dose distributions and longitudinal and transversal fluence profiles for both passive scattering and active scanning modalities. 3D dose distributions in phantom and patient geometries were compared with a commercial treatment planning system, yielding a gamma-index pass rate of above 94% (using FoCa’s most accurate algorithm) for all cases considered. Finally, the inverse treatment planning suite was used to produce the first prototype of intensity-modulated, passive-scattered proton therapy, using 13 passive scattering proton fields and multi-leaf modulation to produce a concave dose distribution on a cylindrical solid water phantom without any field-specific compensator.

  8. The adaptation of megavoltage cone beam CT for use in standard radiotherapy treatment planning.

    PubMed

    Thomas, T Hannah Mary; Devakumar, D; Purnima, S; Ravindran, B Paul

    2009-04-07

    Potential areas where megavoltage computed tomography (MVCT) could be used are second- and third-phase treatment planning in 3D conformal radiotherapy and IMRT, adaptive radiation therapy, single fraction palliative treatment and for the treatment of patients with metal prostheses. A feasibility study was done on using MV cone beam CT (CBCT) images generated by proprietary 3D reconstruction software based on the FDK algorithm for megavoltage treatment planning. The reconstructed images were converted to a DICOM file set. The pixel values of megavoltage cone beam computed tomography (MV CBCT) were rescaled to those of kV CT for use with a treatment planning system. A calibration phantom was designed and developed for verification of geometric accuracy and CT number calibration. The distance measured between two marker points on the CBCT image and the physical dimension on the phantom were in good agreement. Point dose verification for a 10 cm x 10 cm beam at a gantry angle of 0 degrees and SAD of 100 cm were performed for a 6 MV beam for both kV and MV CBCT images. The point doses were found to vary between +/-6.1% of the dose calculated from the kV CT image. The isodose curves for 6 MV for both kV CT and MV CBCT images were within 2% and 3 mm distance-to-agreement. A plan with three beams was performed on MV CBCT, simulating a treatment plan for cancer of the pituitary. The distribution obtained was compared with those corresponding to that obtained using the kV CT. This study has shown that treatment planning with MV cone beam CT images is feasible.

  9. [Radiotherapy of hypopharynx cancers].

    PubMed

    Pointreau, Y; Lafond, C; Trémolières, P; Legouté, F; Servagi-Vernat, S; Giraud, P; Maingon, P; Calais, G; Lapeyre, M

    2016-09-01

    The intensity-modulated radiotherapy is the gold standard in the treatment of hypopharynx cancers. Early T1 and T2 tumours could be treated by exclusive radiotherapy or surgery. For tumours requiring total pharyngolaryngectomy (T2 or T3), induction chemotherapy followed by exclusive radiotherapy or concurrent chemoradiotherapy are possible. For T4 tumours, surgery must be proposed. The treatment of lymph nodes is based on the initial treatment of the primary tumour. In non-surgical procedure, in case of sequential radiotherapy, curative dose is 70Gy and prophylactic dose is 50Gy. An integrated simultaneous boost radiotherapy is allowed (70Gy in 2Gy per fraction and 56Gy in 1.8Gy per fraction or 70Gy in 2.12Gy per fraction). Postoperatively, radiotherapy is used for locally advanced cancers with dose levels based on pathologic criteria (66Gy for R1 resection, 50 to 54Gy for complete resection). Volume delineation is based on guidelines.

  10. Hypofractionated stereotactic radiotherapy of limited brain metastases: a single-centre individualized treatment approach

    PubMed Central

    2012-01-01

    Background We retrospectively report treatment results of our single-centre experience with hypofractionated stereotactic radiotherapy (hfSRT) of limited brain metastases in primary and recurrence disease situations. Our aim was to find the most effective and safe dose concept. Methods From 04/2006 to 12/2010, 75 patients, with 108 intracranial metastases, were treated with hfSRT. 52 newly diagnosed metastases (48%), without up-front whole brain radiotherapy (WBRT), received hfSRT as a primary treatment. 56 metastases (52%) received a prior WBRT and were treated in this study in a recurrence situation. Main fractionation concepts used for primary hfSRT were 6-7x5 Gy (61.5%) and 5x6 Gy (19.2%), for recurrent hfSRT 7-10x4 Gy (33.9%) and 5-6x5 Gy (33.9%). Results Median overall survival (OS) of all patients summed up to 9.1 months, actuarial 6-and 12-month-OS was 59% and 35%, respectively. Median local brain control (LC) was 11.9 months, median distant brain control (DC) 3.9 months and intracranial control (IC) 3.4 months, respectively. Variables with significant influence on OS were Gross Tumour Volume (GTV) (p = 0.019), the biological eqivalent dose (calculated on a 2 Gy single dose, EQD2, α/β = 10) < and ≥ median of 39 Gy (p = 0.012), extracerebral activity of the primary tumour (p < 0.001) and the steroid uptake during hfSRT (p = 0.03). LC was significantly influenced by the EQD2, ≤ and > 35 Gy (p = 0.004) in both uni- and multivariate Cox regression analysis. Median LC was 14.9 months for EQD2 >35 Gy and 3.4 months for doses ≤35 Gy, respectively. Early treatment related side effects were usually mild. Nevertheless, patients with a EQD2 >35 Gy had higher rates of toxicity (31%) than ≤35 Gy (8.3%, p=0.026). Conclusion Comparing different dose concepts in hfSRT, a cumulative EQD2 of ≥35 Gy seems to be the most effective concept in patients with primary or recurrent limited brain metastases. Despite higher rates of only mild toxicity, this concept

  11. [Status report of Hungarian radiotherapy based on treatment data, available infrastucture, and human resources].

    PubMed

    Polgár, Csaba; Major, Tibor; Király, Réka; Fodor, János; Kásler, Miklós

    2015-06-01

    The purpose of the study is to report the status of Hungarian radiotherapy (RT) based on the assessment of treatment data in years 2012 to 2014, available infrastructure, and RT staffing. Between December 2014 and January 2015, a RT questionnaire including 3 parts (1. treatment data; 2. infrastructure; 3. staffing) was sent out to all Hungarian RT centers (n=12). All RT centers responded to all questions of the survey. 1. Treatment data: In 2014, 33,162 patients were treated with RT: 31,678 (95.5%) with teletherapy, and 1484 (4.5%) with brachytherapy (BT). Between 2012 and 2014, the number of patients treated with radiotherapy increased with 6.6%, but the number of BT patients decreased by 11%. Forty-two percent of all patients were treated in the two centers of the capital: 9235 patients (28%) at the National Institute of Oncology (NIO), and 4812 (14%) at the Municipial Oncoradiology Center (MOC). Out of the patients treated on megavoltage RT units (n=22,239), only 901 (4%) were treated with intensity-modulated RT (IMRT), and 2018 (9%) with image-guided RT (IGRT). In 2014, 52% of all BT treatments were performed in Budapest: NIO - 539 patients (36%); MOC - 239 patients (16%); and BT was not available in 3 RT centers. Prostate I-125 seed implants and interstitial breast BT was utilized in one, prostate HDR BT in two, and head&neck implants in three centers. 2. Infrastructure: Including ongoing development projects funded by the European Union, by the end of year 2015, 39 megavoltage teletherapy units, and 12 HDR BT units will be in use in 13 available Hungarian RT centers. 3. Staffing: Actually, 92 radiation oncologists (RO), 29 RT residents, 61 medical physicists, and 229 radiation therapy technologists are working in 12 RT centers. There are 23 vacant positions (including 11 RO positions) available at the Hungarian RT centers. According to the professional minimal requirements and WHO guidelines, the implementation of 11 new linear accelerators, and 1 BT units

  12. Investigation of patient, tumour and treatment variables affecting residual motion for respiratory-gated radiotherapy

    NASA Astrophysics Data System (ADS)

    George, R.; Ramakrishnan, V.; Siebers, J. V.; Chung, T. D.; Keall, P. J.

    2006-10-01

    Respiratory gating can reduce the apparent respiratory motion during imaging and treatment; however, residual motion within the gating window remains. Respiratory training can improve respiratory reproducibility and, therefore, the efficacy of respiratory-gated radiotherapy. This study was conducted to determine whether residual motion during respiratory gating is affected by patient, tumour or treatment characteristics. The specific aims of this study were to: (1) identify significant characteristics affecting residual motion, (2) investigate time trends of residual motion over a period of days (inter-session) and (3) investigate time trends of residual motion within the same day (intra-session). Twenty-four lung cancer patients were enrolled in an Institutional Review Board (IRB)-approved protocol. For approximately five sessions, 331 four-minute, respiratory motion traces were acquired with free breathing, audio instructions and audio-visual biofeedback for each patient. The residual motion was quantified by the standard deviation of the displacement within the gating window. The generalized linear model was used to obtain coefficients for each variable within the model and to evaluate the clinical and statistical significance. The statistical significance was determined by a p-value <0.05, while effect sizes of >=0.1 cm (one standard deviation) were considered clinically significant. This data analysis was applied to patient, tumour and treatment variables. Inter- and intra-session variations were also investigated. The only variable that was significant for both inhale- and exhale-based gating was disease type. In addition, visual-training displacement, breathing type and Karnofsky performance status (KPS) values were significant for inhale-based gating, and dose-per-fraction was significant for exhale-based gating. Temporal respiratory variations within and between sessions were observed for individual patients. However inter- and intra-session analyses did

  13. Hypofractionated Proton Boost Combined with External Beam Radiotherapy for Treatment of Localized Prostate Cancer

    PubMed Central

    Johansson, Silvia; Åström, Lennart; Sandin, Fredrik; Isacsson, Ulf; Montelius, Anders; Turesson, Ingela

    2012-01-01

    Proton boost of 20 Gy in daily 5 Gy fractions followed by external beam radiotherapy (EBRT) of 50 Gy in daily 2 Gy fractions were given to 278 patients with prostate cancer with T1b to T4N0M0 disease. Fifty-three percent of the patients received neoadjuvant androgen deprivation therapy (N-ADT). The medium followup was 57 months. The 5-year PSA progression-free survival was 100%, 95%, and 74% for low-, intermediate-, and high-risk patients, respectively. The toxicity evaluation was supported by a patient-reported questionnaire before every consultant visit. Cumulative probability and actuarial prevalence of genitourinary (GU) and gastrointestinal (GI) toxicities are presented according to the RTOG classification. N-ADT did not influence curability. Mild pretreatment GU-symptoms were found to be a strong predictive factor for GU-toxicity attributable to treatment. The actuarial prevalence declined over 3 to 5 years for both GU and GI toxicities, indicating slow resolution of epithelial damage to the genitourinary and gastrointestinal tract. Bladder toxicities rather than gastrointestinal toxicities seem to be dose limiting. More than 5-year followup is necessary to reveal any sign of true progressive late side effects of the given treatment. Hypofractionated proton-boost combined with EBRT is associated with excellent curability of localized PC and acceptable frequencies of treatment toxicity. PMID:22848840

  14. Comparison of 2-dimensional and 3-dimensional conformal treatment plans in gastric cancer radiotherapy.

    PubMed

    Adas, Yasemin Guzle; Andrieu, Meltem Nalca; Hicsonmez, Ayse; Atakul, Tugba; Dirican, Bahar; Aktas, Caner; Yilmaz, Sercan; Akyurek, Serap; Gokce, Saban Cakir; Ergocen, Salih

    2014-01-01

    Postoperative chemoradiotherapy is accepted as standard treatment for stage IB-IV, M0 gastric cancer. Radiotherapy (RT) planning of gastric cancer is important because of the low radiation tolerance of surrounding critical organs. The purpose of this study was to compare the dosimetric aspects of 2-dimensional (2D) and 3-dimensional (3D) treatment plans, with the twin aims of evaluating the adequacy of 2D planning fields on coverage of planning target volume (PTV) and 3D conformal plans for both covering PTV and reducing the normal tissue doses. Thirty-six patients with stage II-IV gastric adenocarcinoma were treated with adjuvant chemoradiotherapy using 3DRT. For each patient, a second 2D treatment plan was generated. The two techniques were compared for target volume coverage and dose to normal tissues using dose volume histogram (DVH) analysis. 3DRT provides more adequate coverage of the target volume. Comparative DVHs for the left kidney and spinal cord demonstrate lower radiation doses with the 3D technique. 3DRT produced better dose distributions and reduced radiation doses to left kidney and spinal cord compared to the 2D technique. For this reason it can be predicted that 3DRT will result in better tumor control and less normal tissue complications.

  15. Hypofractionated proton boost combined with external beam radiotherapy for treatment of localized prostate cancer.

    PubMed

    Johansson, Silvia; Aström, Lennart; Sandin, Fredrik; Isacsson, Ulf; Montelius, Anders; Turesson, Ingela

    2012-01-01

    Proton boost of 20 Gy in daily 5 Gy fractions followed by external beam radiotherapy (EBRT) of 50 Gy in daily 2 Gy fractions were given to 278 patients with prostate cancer with T1b to T4N0M0 disease. Fifty-three percent of the patients received neoadjuvant androgen deprivation therapy (N-ADT). The medium followup was 57 months. The 5-year PSA progression-free survival was 100%, 95%, and 74% for low-, intermediate-, and high-risk patients, respectively. The toxicity evaluation was supported by a patient-reported questionnaire before every consultant visit. Cumulative probability and actuarial prevalence of genitourinary (GU) and gastrointestinal (GI) toxicities are presented according to the RTOG classification. N-ADT did not influence curability. Mild pretreatment GU-symptoms were found to be a strong predictive factor for GU-toxicity attributable to treatment. The actuarial prevalence declined over 3 to 5 years for both GU and GI toxicities, indicating slow resolution of epithelial damage to the genitourinary and gastrointestinal tract. Bladder toxicities rather than gastrointestinal toxicities seem to be dose limiting. More than 5-year followup is necessary to reveal any sign of true progressive late side effects of the given treatment. Hypofractionated proton-boost combined with EBRT is associated with excellent curability of localized PC and acceptable frequencies of treatment toxicity.

  16. Adjuvant radiotherapy in the treatment of gall bladder carcinoma: What is the current evidence.

    PubMed

    Mallick, Supriya; Benson, Rony; Haresh, K P; Julka, P K; Rath, G K

    2016-03-01

    Gall bladder carcinoma (GBC) is considered the fifth most common one of the most aggressive gastro intestinal tract malignancies. Owing to their large incidence randomised controlled trials have hardly been conducted to look into their optimum treatment. Over the years surgical resection has been considered the only curative treatment of these tumors. However, the outcome still remains guarded. The predominant pattern of failure is loco-regional followed by systemic. Hence, local adjuvant radiation has been used by different institutes with concurrent and adjuvant chemotherapy. The large retrospective series with their limitations showed improved survival in patients with regional spread or tumors infiltrating the liver when treated with adjuvant radiotherapy. In the present era with modern radiation techniques and target delineation radiation may further improve upon the impact without adding to the toxicity profile. Hence, radiation in gall bladder cancer needs a relook to optimize treatment outcome of such aggressive disease. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  17. Treatment outcomes and late complications of 849 patients with nasopharyngeal carcinoma treated with radiotherapy alone

    SciTech Connect

    Yeh, S.-A. . E-mail: yehsa@hotmail.com; Tang Yeh; Lui, C.-C.; Huang, Y.-J.; Huang, E.-Y.

    2005-07-01

    Purpose: The objective of this study was to describe the treatment outcomes and treatment-related complications of nasopharyngeal carcinoma (NPC) patients treated with radiotherapy alone. Methods and Materials: Retrospective analysis was performed on 849 consecutive NPC patients treated between 1983 and 1998 in our institution. Potentially significant patient-related and treatment-related variables were analyzed. Radiation-related complications were recorded. Results: The 5-year overall and disease-free survival rates of these patients were 59% and 52%, respectively. Advanced parapharyngeal space (PPS) invasion showed stronger prognostic value than PPS invasion. Multiple neck lymph node (LN) involvement was demonstrated to be one of the most powerful independent prognostic factors among all LN-related parameters. External beam radiation dose more than 72 Gy was associated with significantly higher incidence of hearing impairment, trismus, and temporal lobe necrosis. Conclusions: We recommend that the extent of PPS should be clarified and stratified. Multiple neck LN involvement could be integrated into the N-classification in further revisions of the American Joint Committee on Cancer stage. Boost irradiation is not suggested for node-negative necks. For node-positive necks, boost irradiation is indicated and a longer interval between initial and boost irradiation would reduce the incidence of neck fibrosis without compromising the neck control rate.

  18. [Can the prophylactic treatment of mycotic mucositis improve the time of performing radiotherapy in head and neck tumors?].

    PubMed

    Gava, A; Ferrarese, F; Tonetto, V; Coghetto, F; Marazzato, G; Zorat, P L

    1996-04-01

    Radiotherapy-related mucositis is the most frequent complication in the patients submitted to irradiation for head and neck cancers. Many such patients may develop mycotic infections which may lead to treatment discontinuation, with possible consequences on the local control of these cancers. In this study, we investigated the efficacy of fluconazole in preventing mycotic mucositis in 80 patients undergoing radiation therapy for head and neck cancers. The patients were randomized to two groups: 41 patients in group A received the supporting treatment we usually administer, plus fluconazole (50 mg/day) starting from the 6th irradiation session throughout the treatment; 39 patients in group B received the same baseline treatment, but were given the drug only when mycotic infections appeared. The clinical characteristics, treated sites, treatment doses and volumes were similar in the two groups of patients. Fluconazole was well tolerated and no early or late toxicity was observed. We had 1 mycotic mucositis and 14 non-scheduled treatment discontinuations in group A, vs. 19 and 30, respectively, in group B. Radiation therapy lasted 52.3 days (mean) in group A and 55.6 days (mean) in group B; the differences were statistically significant. In our experience, fluconazole, used prophylactically from the 6th radiotherapy session on, reduced the number of mycotic infections and improved radiotherapy schedule in our head and neck cancer patients.

  19. Intensity-Modulated Radiotherapy Causes Fewer Side Effects than Three-Dimensional Conformal Radiotherapy When Used in Combination With Brachytherapy for the Treatment of Prostate Cancer

    SciTech Connect

    Forsythe, Kevin; Blacksburg, Seth; Stone, Nelson; Stock, Richard G.

    2012-06-01

    Purpose: To measure the benefits of intensity-modulated radiotherapy (IMRT) compared with three-dimensional conformal radiotherapy (3D-CRT) when used in combination with brachytherapy for the treatment of prostate cancer. Methods and Materials: We conducted a retrospective review of all patients with localized prostate cancer who received external-beam radiotherapy (EBRT) in combination with brachytherapy with at least 1 year follow-up (n = 812). Combination therapy consisted of {sup 103}Pd or {sup 125}I implant, followed by a course of EBRT. From 1993 to March 2003 521 patients were treated with 3D-CRT, and from April 2003 to March 2009 291 patients were treated with IMRT. Urinary symptoms were prospectively measured with the International Prostate Symptom Score questionnaire with a single quality of life (QOL) question; rectal bleeding was assessed per the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Schema. The Pearson {chi}{sup 2} test was used to compare toxicities experienced by patients who were treated with either IMRT or 3D-CRT. Logistic regression analyses were also performed to rule out possible confounding factors. Results: Within the first 3 months after treatment, patients treated with 3D-CRT scored their urinary symptoms as follows: 19% mild, 44% moderate, and 37% severe; patients treated with IMRT scored their urinary symptoms as follows: 36% mild, 47% moderate, and 17% severe (p < 0.001). The 3D-CRT patients rated their QOL as follows: 35% positive, 20% neutral, and 45% negative; IMRT patients rated their QOL as follows: 51% positive, 18% neutral, and 31% negative (p < 0.001). After 1 year of follow-up there was no longer any difference in urinary morbidity between the two groups. Logistic regression confirmed the differences in International Prostate Symptom Score and QOL in the acute setting (p < 0.001 for both). Grade {>=}2 rectal bleeding was reported by 11% of 3D

  20. Children Undergoing Radiotherapy: Swedish Parents' Experiences and Suggestions for Improvement.

    PubMed

    Ångström-Brännström, Charlotte; Engvall, Gunn; Mullaney, Tara; Nilsson, Kristina; Wickart-Johansson, Gun; Svärd, Anna-Maja; Nyholm, Tufve; Lindh, Jack; Lindh, Viveca

    2015-01-01

    Approximately 300 children, from 0 to 18 years old, are diagnosed with cancer in Sweden every year. Of these children, 80-90 of them undergo radiotherapy treatment for their cancer. Although radiotherapy is an encounter with advanced technology, few studies have investigated the child's and the parent's view of the procedure. As part of an ongoing multicenter study aimed to improve patient preparation and the care environment in pediatric radiotherapy, this article reports the findings from interviews with parents at baseline. The aim of the present study was twofold: to describe parents' experience when their child undergoes radiotherapy treatment, and to report parents' suggestions for improvements during radiotherapy for their children. Sixteen mothers and sixteen fathers of children between 2-16 years old with various cancer diagnoses were interviewed. Data were analyzed using content analysis. The findings showed that cancer and treatment turns people's lives upside down, affecting the entire family. Further, the parents experience the child's suffering and must cope with intense feelings. Radiotherapy treatment includes preparation by skilled and empathetic staff. The parents gradually find that they can deal with the process; and lastly, parents have suggestions for improvements during the radiotherapy treatment. An overarching theme emerged: that despair gradually turns to a sense of security, with a sustained focus on and close interaction with the child. In conclusion, an extreme burden was experienced around the start of radiotherapy, though parents gradually coped with the process.

  1. Children Undergoing Radiotherapy: Swedish Parents’ Experiences and Suggestions for Improvement

    PubMed Central

    Mullaney, Tara; Nilsson, Kristina; Wickart-Johansson, Gun; Svärd, Anna-Maja; Nyholm, Tufve; Lindh, Jack; Lindh, Viveca

    2015-01-01

    Approximately 300 children, from 0 to 18 years old, are diagnosed with cancer in Sweden every year. Of these children, 80–90 of them undergo radiotherapy treatment for their cancer. Although radiotherapy is an encounter with advanced technology, few studies have investigated the child’s and the parent’s view of the procedure. As part of an ongoing multicenter study aimed to improve patient preparation and the care environment in pediatric radiotherapy, this article reports the findings from interviews with parents at baseline. The aim of the present study was twofold: to describe parents’ experience when their child undergoes radiotherapy treatment, and to report parents’ suggestions for improvements during radiotherapy for their children. Sixteen mothers and sixteen fathers of children between 2–16 years old with various cancer diagnoses were interviewed. Data were analyzed using content analysis. The findings showed that cancer and treatment turns people’s lives upside down, affecting the entire family. Further, the parents experience the child’s suffering and must cope with intense feelings. Radiotherapy treatment includes preparation by skilled and empathetic staff. The parents gradually find that they can deal with the process; and lastly, parents have suggestions for improvements during the radiotherapy treatment. An overarching theme emerged: that despair gradually turns to a sense of security, with a sustained focus on and close interaction with the child. In conclusion, an extreme burden was experienced around the start of radiotherapy, though parents gradually coped with the process. PMID:26509449

  2. A DVH-guided IMRT optimization algorithm for automatic treatment planning and adaptive radiotherapy replanning

    SciTech Connect

    Zarepisheh, Masoud; Li, Nan; Long, Troy; Romeijn, H. Edwin; Tian, Zhen; Jia, Xun; Jiang, Steve B.

    2014-06-15

    Purpose: To develop a novel algorithm that incorporates prior treatment knowledge into intensity modulated radiation therapy optimization to facilitate automatic treatment planning and adaptive radiotherapy (ART) replanning. Methods: The algorithm automatically creates a treatment plan guided by the DVH curves of a reference plan that contains information on the clinician-approved dose-volume trade-offs among different targets/organs and among different portions of a DVH curve for an organ. In ART, the reference plan is the initial plan for the same patient, while for automatic treatment planning the reference plan is selected from a library of clinically approved and delivered plans of previously treated patients with similar medical conditions and geometry. The proposed algorithm employs a voxel-based optimization model and navigates the large voxel-based Pareto surface. The voxel weights are iteratively adjusted to approach a plan that is similar to the reference plan in terms of the DVHs. If the reference plan is feasible but not Pareto optimal, the algorithm generates a Pareto optimal plan with the DVHs better than the reference ones. If the reference plan is too restricting for the new geometry, the algorithm generates a Pareto plan with DVHs close to the reference ones. In both cases, the new plans have similar DVH trade-offs as the reference plans. Results: The algorithm was tested using three patient cases and found to be able to automatically adjust the voxel-weighting factors in order to generate a Pareto plan with similar DVH trade-offs as the reference plan. The algorithm has also been implemented on a GPU for high efficiency. Conclusions: A novel prior-knowledge-based optimization algorithm has been developed that automatically adjust the voxel weights and generate a clinical optimal plan at high efficiency. It is found that the new algorithm can significantly improve the plan quality and planning efficiency in ART replanning and automatic treatment

  3. Proton Radiotherapy for Prostate Cancer Is Not Associated With Post-Treatment Testosterone Suppression

    SciTech Connect

    Nichols, R. Charles; Morris, Christopher G.; Hoppe, Bradford S.; Henderson, Randal H.; Marcus, Robert B.; Mendenhall, William M.; Li Zuofeng; Williams, Christopher R.; Costa, Joseph A.; Mendenhall, Nancy P.

    2012-03-01

    Purpose: Three independent studies of photon (x-ray) radiotherapy (RT) for prostate cancer have demonstrated evidence of testosterone suppression after treatment. The present study was undertaken to determine whether this would also be the case with conformal protons. Methods and Materials: Between August 2006 and October 2007, 171 patients with low- and intermediate-risk prostate cancer were enrolled and underwent treatment according to University of Florida Proton Therapy Institute institutional review board-approved PR01 and PR02 protocols. Of the 171 patients, 18 were excluded because they had received androgen deprivation therapy either before (n = 17) or after (n = 1) RT. The pretreatment serum testosterone level was available for 150 of the remaining 153 patients. These 150 patients were included in the present study. The post-treatment levels were compared with the pretreatment levels. Results: The median baseline pretreatment serum testosterone level was 357.9 ng/dL. The median post-treatment testosterone value was 375.5 ng/dL at treatment completion (p = .1935) and 369.9 ng/dL (p = .1336), 348.7 ng/dL (p = .7317), 353.4 ng/dL (p = .6996), and 340.9 ng/dL (p = .1669) at 6, 12, 18, and 24 months after proton therapy, respectively. Conclusions: Conformal proton therapy to the prostate, as delivered using University of Florida Proton Therapy Institute PR01 and PR02 protocols, did not appear to significantly affect the serum testosterone levels within 24 months after RT.

  4. Radiotherapy as an effective treatment modality for follicular lymphoma: a single institution experience

    PubMed Central

    Choi, Seo Hee; Cho, Jaeho; Kim, Jin Seok; Cheong, June-Won

    2015-01-01

    Purpose Follicular lymphoma (FL) is an indolent non-Hodgkin's lymphoma that is highly sensitive to radiotherapy (RT). However, the effectiveness of RT has not been well established. We reviewed our experiences to assess the role of RT for FL and analyze treatment results. Materials and Methods Retrospective analysis was done on 29 patients who received first RT between January 2003 and August 2013. Of 23 early stage (stage I, II) patients, 16 received RT alone, four received chemotherapy followed by RT, two received RT postoperatively, and one received salvage RT for relapse after resection. Six advanced-stage (stage III, IV) patients received RT after chemotherapy: two received consolidation RT, three received salvage RT for residual lesions, and one received RT for progressive sites. Median RT dose was 30.6 Gy (range, 21.6 to 48.6 Gy). Median follow-up duration was 62 months (range, 6 to 141 months). Results All patients showed complete response in the radiation field. Eight outfield relapses were reported. Seven patients received salvage treatment (three chemotherapy, four RT). Four patients showed excellent responses, especially to RT. Estimated 5-year and 10-year relapse-free survivals were 72% and 60%. In the RT-alone group, 5-year relapse-free survival was 74.5%. All advanced-stage patients were disease-free with 100% 5-year overall survival. Disease-specific death was noted in only one patient; four others died of other unrelated causes. No significant toxicity was reported. Conclusion RT resulted in excellent treatment outcomes for all FL stages when used as a primary treatment modality for early stage or salvage-treatment modality for advanced-stage disease. PMID:26756031

  5. Intensity-Modulated Radiotherapy in Postoperative Treatment of Oral Cavity Cancers

    SciTech Connect

    Gomez, Daniel R. Zhung, Joanne E.; Gomez, Jennifer; Chan, Kelvin; Wu, Abraham J.; Wolden, Suzanne L.; Pfister, David G.; Shaha, Ashok; Shah, Jatin P.; Kraus, Dennis H.; Wong, Richard J.; Lee, Nancy Y.

    2009-03-15

    Purpose: To present our single-institution experience of intensity-modulated radiotherapy (IMRT) for oral cavity cancer. Methods and Materials: Between September 2000 and December 2006, 35 patients with histologically confirmed squamous cell carcinoma of the oral cavity underwent surgery followed by postoperative IMRT. The sites included were buccal mucosa in 8, oral tongue in 11, floor of the mouth in 9, gingiva in 4, hard palate in 2, and retromolar trigone in 1. Most patients had Stage III-IV disease (80%). Ten patients (29%) also received concurrent postoperative chemotherapy with IMRT. The median prescribed radiation dose was 60 Gy. Results: The median follow-up for surviving patients was 28.1 months (range, 11.9-85.1). Treatment failure occurred in 11 cases as follows: local in 4, regional in 2, and distant metastases in 5. Of the 5 patients with distant metastases, 2 presented with dermal metastases. The 2- and 3-year estimates of locoregional progression-free survival, distant metastasis-free survival, disease-free survival, and overall survival were 84% and 77%, 85% and 85%, 70% and 64%, and 74% and 74%, respectively. Acute Grade 2 or greater dermatitis, mucositis, and esophageal reactions were experienced by 54%, 66%, and 40% of the patients, respectively. Documented late complications included trismus (17%) and osteoradionecrosis (5%). Conclusion: IMRT as an adjuvant treatment after surgical resection for oral cavity tumors is feasible and effective, with promising results and acceptable toxicity.

  6. Treatment of late sequelae after radiotherapy for head and neck cancer.

    PubMed

    Strojan, Primož; Hutcheson, Katherine A; Eisbruch, Avraham; Beitler, Jonathan J; Langendijk, Johannes A; Lee, Anne W M; Corry, June; Mendenhall, William M; Smee, Robert; Rinaldo, Alessandra; Ferlito, Alfio

    2017-09-01

    Radiotherapy (RT) is used to treat approximately 80% of patients with cancer of the head and neck. Despite enormous advances in RT planning and delivery, a significant number of patients will experience radiation-associated toxicities, especially those treated with concurrent systemic agents. Many effective management options are available for acute RT-associated toxicities, but treatment options are much more limited and of variable benefit among patients who develop late sequelae after RT. The adverse impact of developing late tissue damage in irradiated patients may range from bothersome symptoms that negatively affect their quality of life to severe life-threatening complications. In the region of the head and neck, among the most problematic late effects are impaired function of the salivary glands and swallowing apparatus. Other tissues and structures in the region may be at risk, depending mainly on the location of the irradiated tumor relative to the mandible and hearing apparatus. Here, we review the available evidence on the use of different therapeutic strategies to alleviate common late sequelae of RT in head and neck cancer patients, with a focus on the critical assessment of the treatment options for xerostomia, dysphagia, mandibular osteoradionecrosis, trismus, and hearing loss. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Control of a HexaPOD treatment couch for robot-assisted radiotherapy.

    PubMed

    Hermann, Christian; Ma, Lei; Wilbert, Jürgen; Baier, Kurt; Schilling, Klaus

    2012-10-01

    Moving tumors, for example in the vicinity of the lungs, pose a challenging problem in radiotherapy, as healthy tissue should not be irradiated. Apart from gating approaches, one standard method is to irradiate the complete volume within which a tumor moves plus a safety margin containing a considerable volume of healthy tissue. This work deals with a system for tumor motion compensation using the HexaPOD® robotic treatment couch (Medical Intelligence GmbH, Schwabmünchen, Germany). The HexaPOD, carrying the patient during treatment, is instructed to perform translational movements such that the tumor motion, from the beams-eye view of the linear accelerator, is eliminated. The dynamics of the HexaPOD are characterized by time delays, saturations, and other non-linearities that make the design of control a challenging task. The focus of this work lies on two control methods for the HexaPOD that can be used for reference tracking. The first method uses a model predictive controller based on a model gained through system identification methods, and the second method uses a position control scheme useful for reference tracking. We compared the tracking performance of both methods in various experiments with real hardware using ideal reference trajectories, prerecorded patient trajectories, and human volunteers whose breathing motion was compensated by the system.

  8. Adjuvant treatment with concomitant radiotherapy and chemotherapy in high-risk endometrial cancer: a clinical experience.

    PubMed

    De Marzi, Patrizia; Frigerio, Luigi; Cipriani, Sonia; Parazzini, Fabio; Busci, Luisa; Carlini, Laura; Viganò, Riccardo; Mangili, Giorgia

    2010-03-01

    The concurrent use of radiotherapy (RT) and chemotherapy (CT) as adjuvant treatment after surgery in high-risk endometrial cancer has been generally considered cautiously. Recently some of us have reported preliminary data on the efficacy and tolerability of concomitant CT and RT. In this paper, we update our experience. A total of 47 patients aged >18 years and <80 years with histological diagnosis of high-risk endometrial endometrioid carcinomas entered the study. Inclusion criteria were stages IC G3, IIB, IIIA (patients with positive washing without other unfavourable prognostic factors were omitted), IIIB and IIIC. The radiation plan consisted of a total dose of 50.4 Gy, given in five fractions per week (1.8 Gy: daily dose) for 6 weeks. Paclitaxel (P) at a dose of 60 mg/m(2) was infused intravenously in 250 mL of normal saline for 1 h once weekly during RT for 5 weeks. Three further cycles of Paclitaxel, at a dose of 80 mg/m(2), have been given weekly at the end of RT. There was no life-threatening toxicity. The overall 5-year relapse-free survival was 81.8% (95% CI, 65.2-90.9). The 5-year percent overall disease-specific survival was 88.4% (95% CI, 71.1-95.6). These results, based on a larger series, support our previous data: Paclitaxel plus RT may represent an effective and well-tolerated treatment in high-risk endometrial cancer patients.

  9. Dosimetry characterization of a multibeam radiotherapy treatment for age-related macular degeneration

    SciTech Connect

    Lee, Choonsik; Chell, Erik; Gertner, Michael; Hansen, Steven; Howell, Roger W.; Hanlon, Justin; Bolch, Wesley E.

    2008-11-15

    Age-related macular degeneration (ARMD) is a major health problem worldwide. Advanced ARMD, which ultimately leads to profound vision loss, has dry and wet forms, which account for 20% and 80% of cases involving severe vision loss, respectively. A new device and approach for radiation treatment of ARMD has been recently developed by Oraya Therapeutics, Inc. (Newark, CA). The goal of the present study is to provide a initial dosimetry characterization of the proposed radiotherapy treatment via Monte Carlo radiation transport simulation. A 3D eye model including cornea, anterior chamber, lens, orbit, fat, sclera, choroid, retina, vitreous, macula, and optic nerve was carefully designed. The eye model was imported into the MCNPX2.5 Monte Carlo code and radiation transport simulations were undertaken to obtain absorbed doses and dose volume histograms (DVH) to targeted and nontargeted structures within the eye. Three different studies were undertaken to investigate (1) available beam angles that maximized the dose to the macula target tissue, simultaneously minimizing dose to normal tissues, (2) the energy dependency of the DVH for different x-ray energies (80, 100, and 120 kVp), and (3) the optimal focal spot size among options of 0.0, 0.4, 1.0, and 5.5 mm. All results were scaled to give 8 Gy to the macula volume, which is the current treatment requirement. Eight beam treatment angles are currently under investigation. In all eight beam angles, the source-to-target distance is 13 cm, and the polar angle of entry is 30 degree sign from the geometric axis of the eye. The azimuthal angle changes in eight increments of 45 degree sign in a clockwise fashion, such that an azimuthal angle of 0 degree sign corresponds to the 12 o'clock position when viewing the treated eye. Based on considerations of nontarget tissue avoidance, as well as facial-anatomical restrictions on beam delivery, treatment azimuthal angles between 135 degree sign and 225 degree sign would be available

  10. Radiotherapy Treatment of Early-Stage Prostate Cancer with IMRT and Protons: A Treatment Planning Comparison

    SciTech Connect

    Trofimov, Alexei Nguyen, Paul L.; Coen, John J.; Doppke, Karen P.; Schneider, Robert J. C.; Adams, Judith A. C.; Bortfeld, Thomas R.; Zietman, Anthony L.; DeLaney, Thomas F.; Shipley, William U.

    2007-10-01

    Purpose: To compare intensity-modulated photon radiotherapy (IMRT) with three-dimensional conformal proton therapy (3D-CPT) for early-stage prostate cancer, and explore the potential utility of intensity-modulated proton therapy (IMPT). Methods and Materials: Ten patients were planned with both 3D-CPT (two parallel-opposed lateral fields) and IMRT (seven equally spaced coplanar fields). Prescribed dose was 79.2 Gy (or cobalt Gray-equivalent, [CGE] for protons) to the prostate gland. Dose-volume histograms, dose conformity, and equivalent uniform dose (EUD) were compared. Additionally, plans were optimized for 3D-CPT with nonstandard beam configuration, and for IMPT assuming delivery with beam scanning. Results: At least 98% of the planning target volume received the prescription dose. IMRT plans yielded better dose conformity to the target, whereas proton plans achieved higher dose homogeneity and better sparing of rectum and bladder in the range below 30 Gy/CGE. Bladder volumes receiving more than 70 Gy/CGE (V{sub 70}) were reduced, on average, by 34% with IMRT vs. 3D-CPT, whereas rectal V{sub 70} were equivalent. EUD from 3D-CPT and IMRT plans were indistinguishable within uncertainties for both bladder and rectum. With the use of small-angle lateral-oblique fields in 3D-CPT and IMPT, the rectal V{sub 70} was reduced by up to 35% compared with the standard lateral configuration, whereas the bladder V{sub 70} increased by less than 10%. Conclusions: In the range higher than 60 Gy/CGE, IMRT achieved significantly better sparing of the bladder, whereas rectal sparing was similar with 3D-CPT and IMRT. Dose to healthy tissues in the range lower than 50% of the target prescription was substantially lower with proton therapy.

  11. Deep architecture neural network-based real-time image processing for image-guided radiotherapy.

    PubMed

    Mori, Shinichiro

    2017-08-01

    To develop real-time image processing for image-guided radiotherapy, we evaluated several neural network models for use with different imaging modalities, including X-ray fluoroscopic image denoising. Setup images of prostate cancer patients were acquired with two oblique X-ray fluoroscopic units. Two types of residual network were designed: a convolutional autoencoder (rCAE) and a convolutional neural network (rCNN). We changed the convolutional kernel size and number of convolutional layers for both networks, and the number of pooling and upsampling layers for rCAE. The ground-truth image was applied to the contrast-limited adaptive histogram equalization (CLAHE) method of image processing. Network models were trained to keep the quality of the output image close to that of the ground-truth image from the input image without image processing. For image denoising evaluation, noisy input images were used for the training. More than 6 convolutional layers with convolutional kernels >5×5 improved image quality. However, this did not allow real-time imaging. After applying a pair of pooling and upsampling layers to both networks, rCAEs with >3 convolutions each and rCNNs with >12 convolutions with a pair of pooling and upsampling layers achieved real-time processing at 30 frames per second (fps) with acceptable image quality. Use of our suggested network achieved real-time image processing for contrast enhancement and image denoising by the use of a conventional modern personal computer. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  12. Treatment of ORNL process waste

    SciTech Connect

    Berry, J.B.; Brown, C.H. Jr.; Fowler, V.L.; Robinson, S.M.

    1988-01-01

    Because of the shutdown of the hydrofracture process at ORNL, intensive efforts were made to reduce contaminated liquid waste generation rates. Treatment of slightly radioactive process waste has been dramatically improved. The volume of secondary, radioactively contaminated waste streams and the concentration of pollutants discharged to the environment have been reduced. Further improvements, based on results of research and development, are planned. The future value of alternative flowsheets will be compared with process flexibility to determine the optimal upgrade to the treatment plant. 1 ref., 4 figs., 2 tabs.

  13. Concurrent conventionally factionated radiotherapy and weekly docetaxel in the treatment of stage IIIb non-small-cell lung carcinoma

    PubMed Central

    Koukourakis, M I; Bahlitzanakis, N; Froudarakis, M; Giatromanolaki, A; Georgoulias, V; Koumiotaki, S; Christodoulou, M; Kyrias, G; Skarlatos, J; Kostantelos, J; Beroukas, K

    1999-01-01

    Docetaxel has shown remarkable radiosensitizing in vitro properties. In a previous phase I/II dose escalation study in non- small-cell lung cancer (NSCLC) we observed a high response rate after concomitant boost radiotherapy and weekly docetaxel. The maximum tolerated dose was 30 mg m−2 week−1. In the present phase II study we evaluated whether weekly docetaxel and conventionally fractionated radiotherapy could be better tolerated and equally effective in the treatment of locally advanced NSCLC. Thirty-five patients with T3, T4/N2, T3/M0-staged disease were recruited. Docetaxel (30 mg m−2) was given as a 30 min infusion once a week. Asthenia and radiation-induced oesophagitis were the main side-effects of the regimen enforcing 2-week treatment delay in 6/35 (17%) patients and minor delay (3–7 days) in another 11/35 (31%) patients. Neutrophil, platelet and haemoglobin toxicity was minimal, but pronounced lymphocytopenia was observed. Complete response (CR) of the chest disease was observed in 12/35 (34%) patients and partial response in 16/35 (46%). Although not statistically significant (P = 0.19), a higher CR rate (8/18; 44%) was observed in patients who accomplished their therapy within the scheduled treatment time (44–47 days) as compared to patients that interrupted their treatment for several days due to treatment-related toxicity (CR 4/17; 23%). The overall survival and the local progression-free survival at 1 year was 48% and 60% respectively. We conclude that docetaxel combination with radiotherapy is a promising approach for the management of locally advanced NSCLC that results in high CR rate. Further trials with docetaxel-based radiochemotherapy should integrate accelerated radiotherapy together with cytoprotection. © 1999 Cancer Research Campaign PMID:10468298

  14. Salvage Treatment With Hypofractionated Radiotherapy in Patients With Recurrent Small Hepatocellular Carcinoma

    SciTech Connect

    Bae, Sun Hyun; Park, Hee Chul; Lim, Do Hoon; Lee, Jung Ae; Gwak, Geum Yeon; Choi, Moon Seok; Lee, Joon Hyoek; Koh, Kwang Cheol; Paik, Seung Woon; Yoo, Byung Chul

    2012-03-15

    Purpose: To investigate the rates of tumor response and local control in patients with recurrent small hepatocellular carcinoma (HCC) treated with hypofractionated radiotherapy (RT) as a salvage treatment and to evaluate treatment-related toxicities. Methods and Materials: Between 2006 and 2009, a total of 20 patients with recurrent small HCC were treated with hypofractionated RT after the failure of previous treatment. The eligibility criteria for hypofractionated RT were as follows: 1) HCC less than 5 cm, 2) HCC not adjacent to critical organs, 3) HCC without portal vein tumor thrombosis, and 4) less than 15% of normal liver volume that would be irradiated with 50% of prescribed dose. The RT dose was 50 Gy in 10 fractions. The tumor response was determined by CT scans performed 3 months after the end of RT. Results: The median follow-up period after RT was 22 months. The overall survival rates at 1 and 2 years were 100% and 87.9%, respectively. Complete response (CR) was achieved in seven of 20 lesions (35%) evaluated by CT scans performed 3 months after the end of RT. In-field local control was achieved in 85% of patients. Fourteen patients (70%) developed intra-hepatic metastases. Six patients developed grade 1 nausea or anorexia during RT, and two patients had progression of ascites after RT. There was no grade 3 or greater treatment-related toxicities. Conclusions: The current study showed a favorable outcome with respect to hypofractionated RT for small HCC. Partial liver irradiation with 50 Gy in 10 fractions is considered tolerable without severe complications.

  15. [Stereotactic radiotherapy and radiosurgery in treatment of patients with intracranial schwannomas].

    PubMed

    Zolotova, S V; Golanov, A V; Kotel'nikova, T M; Soboleva, O I; Gorlachev, G E; Fil'chenkova, N A; Nikonova, N G; Kapitanov, D N; Makhmudov, U B; Shimanskiĭ, V N; Arutiunov, N V; Pronin, I N

    2010-01-01

    Aim of this study is to assess the role of stereotactic radiosurgery (SRS) and radiotherapy (SRT) in management of cranial nerves schwannomas by analysis of tumor control, clinical response and variables affecting treatment outcomes. Between April 2005 and January 2009 patients with schwannomas of VIII (63), V (14) and caudal nerves (2) were treated in Burdenko Moscow Neurosurgical Institute using linear accelerator. Mean age was 49 years (13-82). In 42 cases radiation treatment was preceded by surgical resection. 13 patients had type I or II neurofibromatosis. Mean volume of the tumor was 3.9 cm3 (0.5-14.4 cm3) and 13.4 cm3 (2.8-41.3 cm3) for SRS and SRT, respectively. Mean SRS dose was 12 Gy (10.8-14.4 Gy) for vestibular schwannomas and 15 Gy (13.2-18 Gy) for schwannomas of other nerves. In hypofractionated SRT the dose of 35 Gy was delivered in 7 fractions or 30 Gy in 6 fractions. In cases of classical fractioning total dose of 50-60 Gy was divided into daily fractions of 1.8-2.0 Gy. Radiographic tumor control rate reached 97.5% at the last follow-up. 5 patients experienced trigeminal dysfunction, it was transient in 3 cases and persistent in 2. Permanent decline in House-Brackmann facial nerve scale developed in 2 of 79 patients. After treatment effective hearing (class I-II) was preserved in 7 of 9 patients (67%) who had same level of hearing before SRS. Linear accelerator-based stereotactic radiation treatment provides long-term tumor control associated with high rates of preservation of neurological functions. No further tumor surgery was necessary in 100% of cases with solitary tumors with a minimal follow-up of 5 years.

  16. Dosimetric impact of image artifact from a wide-bore CT scanner in radiotherapy treatment planning

    SciTech Connect

    Wu, Vincent; Podgorsak, Matthew B.; Tran, Tuan-Anh; Malhotra, Harish K.; Wang, Iris Z.

    2011-07-15

    Purpose: Traditional computed tomography (CT) units provide a maximum scan field-of-view (sFOV) diameter of 50 cm and a limited bore size, which cannot accommodate a large patient habitus or an extended simulation setup in radiation therapy (RT). Wide-bore CT scanners with increased bore size were developed to address these needs. Some scanners have the capacity to reconstruct the CT images at an extended FOV (eFOV), through data interpolation or extrapolation, using projection data acquired with a conventional sFOV. Objects that extend past the sFOV for eFOV reconstruction may generate image artifacts resulting from truncated projection data; this may distort CT numbers and structure contours in the region beyond the sFOV. The purpose of this study was to evaluate the dosimetric impact of image artifacts from eFOV reconstruction with a wide-bore CT scanner in radiotherapy (RT) treatment planning. Methods: Testing phantoms (i.e., a mini CT phantom with equivalent tissue inserts, a set of CT normal phantoms and anthropomorphic phantoms of the thorax and the pelvis) were used to evaluate eFOV artifacts. Reference baseline images of these phantoms were acquired with the phantom centrally positioned within the sFOV. For comparison, the phantoms were then shifted laterally and scanned partially outside the sFOV, but still within the eFOV. Treatment plans were generated for the thoracic and pelvic anthropomorphic phantoms utilizing the Eclipse treatment planning system (TPS) to study the potential effects of eFOV artifacts on dose calculations. All dose calculations of baseline and test treatment plans were carried out using the same MU. Results: Results show that both body contour and CT numbers are altered by image artifacts in eFOV reconstruction. CT number distortions of up to -356 HU for bone tissue and up to 323 HU for lung tissue were observed in the mini CT phantom. Results from the large body normal phantom, which is close to a clinical patient size, show

  17. [Early results of combined treatment (induction chemotherapy and radiotherapy) of patients with squamous cell carcinoma of the oropharynx].

    PubMed

    Szutkowski, Z; Krzakowski, M; Hliniak, A; Wasilewski, M

    1990-01-01

    The results of combined treatment (induction chemotherapy followed by irradiation) in 23 patients with locally advanced squamous cell carcinoma of the oropharynx were presented. Chemotherapy program included Cisplatin 100 mg/m2 i.v. in day 1 and 5-fluorouracil 750 mg/m2 i.v. on day 1-5. The chemotherapy was administered every 3 weeks for maximum 3 cycles. Complete response in 15 patients (65%), stabilization in 4 patients (17%) and progressive disease was found in 3 patients (14%). 20 patients were irradiated with radical intention. Complete response was found in 9 patients (45%) after radiotherapy. Treatment was relatively well-tolerated. Out of 17 patients with at least 6 months' follow-up (range 6-24) 6 patients are alive with no evidence of disease. We estimate the postirradiation reaction as slightly more severe than after radiotherapy alone. The reaction did not influence the prescribed way of fractionation.

  18. [Role of radiotherapy in the treatment of NK/T-cell nasal type and primary cerebral lymphomas].

    PubMed

    Boros, A; Michot, J-M; Hoang-Xuan, K; Mazeron, R

    2016-10-01

    The head and neck are common sites for extranodal non-Hodgkin lymphomas. Radiotherapy plays an important role in the treatment of low-grade lymphomas, with curative or palliative intent. In the case of high-grade lymphomas, its combination with chemotherapy is debated. Its role is however undeniable in two specific entities: NK/T-cell lymphoma NK/T nasal type, and primary central nervous system lymphomas, which are the subject of this review.

  19. [High-intensity focused ultrasound (HIFU): our experience in the treatment of prostate cancer relapsing after radiotherapy].

    PubMed

    Giovanessi, Luca; Peroni, Angelo; Mirabella, Giuseppe; Fugini, Andrea Vismara; Zani, Danilo; Cunico, Sergio Cosciani; Simeone, Claudio

    2011-01-01

    The aim of the study is to evaluate the safety and efficacy of high-intensity focused ultrasound (HIFU) treatment in patients with local prostate cancer recurrence after radiotherapy. From February 2009 to June 2010, 14 patients with prostate cancer recurrence after radiotherapy were selected for HIFU treatment; all patients had a positive TRUS-guided biopsy and the absence of distant metastases was confirmed by computer tomography, PET choline or bone scintigraphy. We classified all patients in 3 groups using D'Amico's classification: 4 patients high risk (PSA >20 ng/ml - 8≤ Gleason Score≤ 10 - clinical stage≥T2c), 8 patients intermediate risk (10 PSAnadir+1.2ng/ml) or after adjuvant therapy introduction. All complications were recorded. Of the 14 patients selected, 12 patients underwent HIFU treatments; 2 patients were excluded because of rectal strictures induced by radiotherapy. At a mean 13 months' follow-up, biochemical success rate was obtained in 1 of the high risk patients and in 5 of the low and intermediate risk patients; 1 man died for a disease not correlated with prostate cancer recurrence. Complications included urinary tract infection, acute urinary retentions, urethral strictures and light stress incontinence. In our experience salvage HIFU is a safe treatment option for local relapse after radiotherapy; its efficacy depends on a careful patient selection.

  20. Technical innovation in adjuvant radiotherapy: Evolution and evaluation of new treatments for today and tomorrow.

    PubMed

    Kunkler, Ian H; Ward, Carol; Langdon, Simon P

    2015-11-01

    Recent innovations in breast cancer radiotherapy include intensity modulated radiotherapy, brachytherapy and intraoperative radiotherapy and current trials are seeking to evaluate their value in optimizing local control while maintaining cosmetic effects. Future clinical dividends in local control and survival may come from the identification of molecular signatures of breast cancer radiosensitivity, the development of predictive signatures and identification of immunohistochemical markers of risk of local recurrence. The importance of tumour heterogeneity is being increasingly recognized as an important factor in determining radiotherapy response and an improved understanding of the biology of the tumour microenvironment may identify targets that allow enhanced radiosensitisation or reversal of radioresistance when inhibited. This review describes recent developments in these areas.

  1. Radiotherapy in Italy after conservative treatment of early breast cancer. A survey by the Italian Society of Radiation Oncology (AIRO).

    PubMed

    Aristei, Cynthia; Amichetti, Maurizio; Ciocca, Mario; Nardone, Luigia; Bertoni, Filippo; Vidali, Cristiana

    2008-01-01

    The aim of surveys on clinical practice is to stimulate discussion and optimize practice. In this paper the current Italian radiotherapy practice after breast-conserving surgery for early breast cancer is described and adherence to national and international guidelines is assessed. Furthermore, results are compared with an earlier survey in northern Italy and international reports. A multiple-choice questionnaire sent to all 138 Italian radiation oncology centers. 48% of centers responded. Most performed breast-conserving surgery when tumor size was < or =3 cm. All centers routinely performed axillary dissection; 45 carried out sentinel node biopsy followed by axillary dissection when the sentinel node was positive. Most centers re-excised when resection margins were positive. The median interval between surgery and radiotherapy, when chemotherapy was not administered, was 60 days. Adjuvant chemotherapy was preferably administered before radiotherapy. Regional lymph nodes were never irradiated in 10 centers; in all others irradiation depended on the number of positive lymph nodes and/or involvement of axillary fat and/or tumor location in medial quadrants. All centers used standard fractionation; hypofractionated schemes were available in 6. Most centers used 4-6 MV photons. In 59 centers the boost dose of 10 Gy could be increased if margins were not negative. All centers ensured patient setup reproducibility. Treatment planning was computerized in 59 centers. The irradiation dose was prescribed at the ICRU point in 56 centers and portal films were made in 54 centers. Intraoperative radiotherapy was used in 4 centers: for partial breast irradiation in 1 and for boost administration in 3 centers. Although the quality of radiotherapy delivery has improved in Italy in recent years, approaches that do not conform to international standards persist.

  2. Clinical Outcome of Adjuvant Treatment of Endometrial Cancer Using Aperture-Based Intensity-Modulated Radiotherapy

    SciTech Connect

    Bouchard, Myriam; Nadeau, Sylvain M.Sc.; Gingras, Luc; Raymond, Paul-Emile; Beaulieu, Frederic; Beaulieu, Luc; Fortin, Andre; Germain, Isabelle

    2008-08-01

    Purpose: To assess disease control and acute and chronic toxicity with aperture-based intensity-modulated radiotherapy (AB-IMRT) for postoperative pelvic irradiation of endometrial cancer. Methods and Materials: Between January and July 2005, after hysterectomy for endometrial cancer, 15 patients received 45 Gy to the pelvis using AB-IMRT. The AB-IMRT plans were generated by an in-house treatment planning system (Ballista). The AB-IMRT plans were used for treatment and were dosimetrically compared with three other approaches: conventional four-field, enlarged four-field, and beamlet-based IMRT (BB-IMRT). Disease control and toxicity were prospectively recorded and compared with retrospective data from 30 patients treated with a conventional four-field technique. Results: At a median follow-up of 27 months (range, 23-30), no relapse was noted among the AB-IMRT group compared with five relapses in the control group (p = 0.1). The characteristics of each group were similar, except for the mean body mass index, timing of brachytherapy, and applicator type used. Patients treated with AB-IMRT experienced more frequent Grade 2 or greater gastrointestinal acute toxicity (87% vs. 53%, p 0.02). No statistically significant difference was noted between the two groups regarding the incidence or severity of chronic toxicities. AB-IMRT plans significantly improved target coverage (93% vs. 76% of planning target volume receiving 45 Gy for AB-IMRT vs. conventional four-field technique, respectively). The sparing of organs at risk was similar to that of BB-IMRT. Conclusion: The results of our study have shown that AB-IMRT provides excellent disease control with equivalent late toxicity compared with the conventional four-field technique. AB-IMRT provided treatment delivery and quality assurance advantages compared with BB-IMRT and could reduce the risk of second malignancy compared with BB-IMRT.

  3. Proton Radiotherapy: The Biological Effect of Treating Alternating Subsets of Fields for Different Treatment Fractions

    SciTech Connect

    Engelsman, Martijn; DeLaney, Thomas F.; Hong, Theodore S.

    2011-02-01

    Purpose: Common practice in proton radiotherapy is to deliver a subset of all fields in the treatment plan on any given treatment day. We investigate using biological modeling if the resulting variation in daily dose to normal tissues has a relevant detrimental biological effect. Methods and Materials: For four patient groups, the cumulative normalized total dose (NTD) was determined for normal tissues (OARs) of each patient using the clinically delivered fractionation schedule (FS{sub clin}), and for hypothetical fractionation schedules delivering all fields every day (FS{sub all}) or only a single field each day (FS{sub single}). Cumulative three-dimensional NTD distributions were summarized using the generalized equivalent uniform dose (gEUD) model. Results: For the skull base/cervical spine chordoma group, the largest effect is a 4-Gy increase in gEUD of the chiasm when treating only a subset of fields on any day. For lung cancer and pancreatic cancer patients, the variation in the gEUD of normal tissues is <0.2 Gy. For the prostate group, FS{sub clin} increases the gEUD of the femoral heads by 9 Gy compared with FS{sub all}. Use of FS{sub single} resulted in the highest NTD to normal tissues for any patient. FS{sub all} resulted in an integral NTD to the patient that is on average 5% lower than FS{sub clin} and 10% lower than FS{sub single}. Conclusion: The effects of field set of the day treatment delivery depend on the tumor site and number of fields treated each day. Modeling these effects may be important for accurate risk assessment.

  4. Silicon strip detector for a novel 2D dosimetric method for radiotherapy treatment verification

    NASA Astrophysics Data System (ADS)

    Bocci, A.; Cortés-Giraldo, M. A.; Gallardo, M. I.; Espino, J. M.; Arráns, R.; Alvarez, M. A. G.; Abou-Haïdar, Z.; Quesada, J. M.; Pérez Vega-Leal, A.; Pérez Nieto, F. J.

    2012-05-01

    The aim of this work is to characterize a silicon strip detector and its associated data acquisition system, based on discrete electronics, to obtain in a near future absorbed dose maps in axial planes for complex radiotherapy treatments, using a novel technique. The experimental setup is based on two phantom prototypes: the first one is a polyethylene slab phantom used to characterize the detector in terms of linearity, percent depth dose, reproducibility, uniformity and penumbra. The second one is a cylindrical phantom, specifically designed and built to recreate conditions close to those normally found in clinical environments, for treatment planning assessment. This system has been used to study the dosimetric response of the detector, in the axial plane of the phantom, as a function of its angle with respect to the irradiation beam. A software has been developed to operate the rotation of this phantom and to acquire signals from the silicon strip detector. As an innovation, the detector was positioned inside the cylindrical phantom parallel to the beam axis. Irradiation experiments were carried out with a Siemens PRIMUS linac operating in the 6 MV photon mode at the Virgen Macarena Hospital. Monte Carlo simulations were performed using Geant4 toolkit and results were compared to Treatment Planning System (TPS) calculations for the absorbed dose-to-water case. Geant4 simulations were used to estimate the sensitivity of the detector in different experimental configurations, in relation to the absorbed dose in each strip. A final calibration of the detector in this clinical setup was obtained by comparing experimental data with TPS calculations.

  5. The Impact of Radiotherapy Fields in the Treatment of Patients With Choroid Plexus Carcinoma

    SciTech Connect

    Mazloom, Ali; Wolff, Johannes E.; Paulino, Arnold C.

    2010-09-01

    Purpose: To perform a comprehensive literature review and analysis of cases dealing with choroid plexus carcinoma (CPC) to determine the optimal radiotherapy (RT) treatment field. Methods and Materials: A PubMed search of English language articles from 1979 to 2008 was performed, yielding 33 articles with 56 patients who had available data regarding RT treatment field. The median age at diagnosis was 2.7 years (range, 1 month-53 years). Of 54 patients with data regarding type of surgery, 21 (38.9%) had complete resection. Chemotherapy was delivered to 27 (48%) as part of initial therapy. The RT treatment volume was the craniospinal axis in 38 (68%), whole brain in 9 (16%), and tumor/tumor bed in 9 (16%). Median follow-up for surviving patients was 40 months. Results: The 5-year overall survival and progression-free survival (PFS) rates were 59.5% and 37.2%, respectively. Complete resection (p = 0.035) and use of craniospinal irradiation (CSI; p = 0.025) were found to positively affect PFS. The 5-year PFS for patients who had CSI vs. whole brain and tumor/tumor bed RT were 44.2% and 15.3%. For the 19 patients who relapsed, 9 (47%) had a recurrence in the RT field, 6 (32%) had a recurrence outside the RT field, and 4 (21%) had a recurrence inside and outside the irradiated field. Conclusion: Patients with CPC who received CSI had better PFS compared with those receiving less than CSI. This study supports the use of CSI in the multimodality management of patients with CPC.

  6. The role of external beam radiotherapy in the treatment of papillary thyroid cancer.

    PubMed

    Lee, Nancy; Tuttle, Michael

    2006-12-01

    The role of external beam radiotherapy (EBRT) in treating thyroid cancer has brought forth controversy. Due to various histologic presentations and different natural histories, there is no uniform approach/recommendation among centers and/or authorities regarding the role of EBRT for thyroid cancer. This is particularly true for papillary thyroid carcinoma (PTC) where the clinical course can range from a disease that is cured with simple surgery to an aggressive form of poorly differentiated thyroid cancer with high rates of recurrence/death from disease. In addition, because the majority of the patients with PTC undergo postoperative radioactive iodine (RAI) treatment, the question remains as to what is the exact role of EBRT for PTC in the setting of RAI treatment? In this issue of Endocrine-Related Cancer, Chow and colleagues identified indications for EBRT and RAI therapy for PTC based on a retrospective review of 1300 patients. The authors concluded that postoperative RAI treatment is indicated in patients with pT2-pT4, pN0-pN1b while postoperative EBRT is recommended for patients with gross residual, positive margin, pT4, pN1b, and lymph nodes>2 cm disease. Other centers have also published their experience on the value of EBRT for PTC but with different indications. The reasons for the variations from different centers are complex. However, when all published results are taken together, the findings confirm the added value of EBRT to the present management of PTC in a select group of patients, particularly those with high risk features. In this commentary, these issues will be discussed and recommendations regarding the role of EBRT will be given.

  7. Impact of the accuracy of automatic tumour functional volume delineation on radiotherapy treatment planning.

    PubMed

    Le Maitre, Amandine; Hatt, Mathieu; Pradier, Olivier; Cheze-le Rest, Catherine; Visvikis, Dimitris

    2012-09-07

    Over the past few years several automatic and semi-automatic PET segmentation methods for target volume definition in radiotherapy have been proposed. The objective of this study is to compare different methods in terms of dosimetry. For such a comparison, a gold standard is needed. For this purpose, realistic GATE-simulated PET images were used. Three lung cases and three H&N cases were designed with various shapes, contrasts and heterogeneities. Four different segmentation approaches were compared: fixed and adaptive thresholds, a fuzzy C-mean and the fuzzy locally adaptive Bayesian method. For each of these target volumes, an IMRT treatment plan was defined. The different algorithms and resulting plans were compared in terms of segmentation errors and ground-truth volume coverage using different metrics (V(95), D(95), homogeneity index and conformity index). The major differences between the threshold-based methods and automatic methods occurred in the most heterogeneous cases. Within the two groups, the major differences occurred for low contrast cases. For homogeneous cases, equivalent ground-truth volume coverage was observed for all methods but for more heterogeneous cases, significantly lower coverage was observed for threshold-based methods. Our study demonstrates that significant dosimetry errors can be avoided by using more advanced image-segmentation methods.

  8. Impact of the accuracy of automatic tumour functional volume delineation on radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Le Maitre, Amandine; Hatt, Mathieu; Pradier, Olivier; Cheze-le Rest, Catherine; Visvikis, Dimitris

    2012-09-01

    Over the past few years several automatic and semi-automatic PET segmentation methods for target volume definition in radiotherapy have been proposed. The objective of this study is to compare different methods in terms of dosimetry. For such a comparison, a gold standard is needed. For this purpose, realistic GATE-simulated PET images were used. Three lung cases and three H&N cases were designed with various shapes, contrasts and heterogeneities. Four different segmentation approaches were compared: fixed and adaptive thresholds, a fuzzy C-mean and the fuzzy locally adaptive Bayesian method. For each of these target volumes, an IMRT treatment plan was defined. The different algorithms and resulting plans were compared in terms of segmentation errors and ground-truth volume coverage using different metrics (V95, D95, homogeneity index and conformity index). The major differences between the threshold-based methods and automatic methods occurred in the most heterogeneous cases. Within the two groups, the major differences occurred for low contrast cases. For homogeneous cases, equivalent ground-truth volume coverage was observed for all methods but for more heterogeneous cases, significantly lower coverage was observed for threshold-based methods. Our study demonstrates that significant dosimetry errors can be avoided by using more advanced image-segmentation methods.

  9. Exploiting biological and physical determinants of radiotherapy toxicity to individualize treatment

    PubMed Central

    Scaife, J E; Barnett, G C; Noble, D J; Jena, R; Thomas, S J; West, C M L

    2015-01-01

    The recent advances in radiation delivery can improve tumour control probability (TCP) and reduce treatment-related toxicity. The use of intensity-modulated radiotherapy (IMRT) in particular can reduce normal tissue toxicity, an objective in its own right, and can allow safe dose escalation in selected cases. Ideally, IMRT should be combined with image guidance to verify the position of the target, since patients, target and organs at risk can move day to day. Daily image guidance scans can be used to identify the position of normal tissue structures and potentially to compute the daily delivered dose. Fundamentally, it is still the tolerance of the normal tissues that limits radiotherapy (RT) dose and therefore tumour control. However, the dose–response relationships for both tumour and normal tissues are relatively steep, meaning that small dose differences can translate into clinically relevant improvements. Differences exist between individuals in the severity of toxicity experienced for a given dose of RT. Some of this difference may be the result of differences between the planned dose and the accumulated dose (DA). However, some may be owing to intrinsic differences in radiosensitivity of the normal tissues between individuals. This field has been developing rapidly, with the demonstration of definite associations between genetic polymorphisms and variation in toxicity recently described. It might be possible to identify more resistant patients who would be suitable for dose escalation, as well as more sensitive patients for whom toxicity could be reduced or avoided. Daily differences in delivered dose have been investigated within the VoxTox research programme, using the rectum as an example organ at risk. In patients with prostate cancer receiving curative RT, considerable daily variation in rectal position and dose can be demonstrated, although the median position matches the planning scan well. Overall, in 10 patients, the mean difference between

  10. Absorbed doses behind bones with MR image-based dose calculations for radiotherapy treatment planning.

    PubMed

    Korhonen, Juha; Kapanen, Mika; Keyrilainen, Jani; Seppala, Tiina; Tuomikoski, Laura; Tenhunen, Mikko

    2013-01-01

    Magnetic resonance (MR) images are used increasingly in external radiotherapy target delineation because of their superior soft tissue contrast compared to computed tomography (CT) images. Nevertheless, radiotherapy treatment planning has traditionally been based on the use of CT images, due to the restrictive features of MR images such as lack of electron density information. This research aimed to measure absorbed radiation doses in material behind different bone parts, and to evaluate dose calculation errors in two pseudo-CT images; first, by assuming a single electron density value for the bones, and second, by converting the electron density values inside bones from T(1)∕T(2)∗-weighted MR image intensity values. A dedicated phantom was constructed using fresh deer bones and gelatine. The effect of different bone parts to the absorbed dose behind them was investigated with a single open field at 6 and 15 MV, and measuring clinically detectable dose deviations by an ionization chamber matrix. Dose calculation deviations in a conversion-based pseudo-CT image and in a bulk density pseudo-CT image, where the relative electron density to water for the bones was set as 1.3, were quantified by comparing the calculation results with those obtained in a standard CT image by superposition and Monte Carlo algorithms. The calculations revealed that the applied bulk density pseudo-CT image causes deviations up to 2.7% (6 MV) and 2.0% (15 MV) to the dose behind the examined bones. The corresponding values in the conversion-based pseudo-CT image were 1.3% (6 MV) and 1.0% (15 MV). The examinations illustrated that the representation of the heterogeneous femoral bone (cortex denser compared to core) by using a bulk density for the whole bone causes dose deviations up to 2% both behind the bone edge and the middle part of the bone (diameter <2.5 cm), but in the opposite directions. The measured doses and the calculated ones in the standard CT image were within 0.4% (through

  11. Short-Course Accelerated Radiotherapy in Palliative Treatment of Advanced Pelvic Malignancies: A Phase I Study

    SciTech Connect

    Caravatta, Luciana; Padula, Gilbert D.A.; Macchia, Gabriella; Ferrandina, Gabriella; Bonomo, Pierluigi; Deodato, Francesco; Massaccesi, Mariangela; Mignogna, Samantha; Tambaro, Rosa; Rossi, Marco; Flocco, Mariano; Scapati, Andrea; and others

    2012-08-01

    Purpose: To define the maximum tolerated dose of a conformal short-course accelerated radiotherapy in patients with symptomatic advanced pelvic cancer. Methods and Materials: A phase I trial in 3 dose-escalation steps was designed: 14 Gy (3.5-Gy fractions), 16 Gy (4-Gy fractions), and 18 Gy (4.5-Gy fractions). The eligibility criteria included locally advanced and/or metastatic pelvic cancer and Eastern Cooperative Oncology Group performance status of {<=}3. Treatment was delivered in 2 days with twice-daily fractionation and at least an 8-hour interval. Patients were treated in cohorts of 6-12 to define the maximum tolerated dose. The dose-limiting toxicity was defined as any acute toxicity of grade 3 or greater, using the Radiation Therapy Oncology Group scale. Pain was recorded using a visual analog scale. The effect on quality of life was evaluated according to Cancer Linear Analog Scale (CLAS). Results: Of the 27 enrolled patients, 11 were male and 16 were female, with a median age of 72 years (range 47-86). The primary tumor sites were gynecologic (48%), colorectal (33.5%), and genitourinary (18.5%). The most frequent baseline symptoms were bleeding (48%) and pain (33%). Only grade 1-2 acute toxicities were recorded. No patients experienced dose-limiting toxicity. With a median follow-up time of 6 months (range 3-28), no late toxicities were observed. The overall (complete plus partial) symptom remission was 88.9% (95% confidence interval 66.0%-97.8%). Five patients (41.7%) had complete pain relief, and six (50%) showed >30% visual analog scale reduction. The overall response rate for pain was 91.67% (95% confidence interval 52.4%-99.9%). Conclusions: Conformal short course radiotherapy in twice-daily fractions for 2 consecutive days was well tolerated up to a total dose of 18 Gy. A phase II study is ongoing to confirm the efficacy on symptom control and quality of life indexes.

  12. A cosmetic evaluation of breast cancer treatment: A randomized study of radiotherapy boost technique

    SciTech Connect

    Vass, Sylvie . E-mail: sylvie.vass@ssss.gouv.qc.ca; Bairati, Isabelle

    2005-08-01

    Purpose: To compare cosmetic results of two different radiotherapy (RT) boost techniques used in the treatment of breast cancer after whole breast radiotherapy and to identify factors affecting cosmetic outcomes. Methods and Materials: Between 1996 and 1998, 142 patients with Stage I and II breast cancer were treated with breast conservative surgery and adjuvant RT. Patients were then randomly assigned to receive a boost dose of 15 Gy delivered to the tumor bed either by iridium 192, or a combination of photons and electrons. Cosmetic evaluations were done on a 6-month basis, with a final evaluation at 36 months after RT. The evaluations were done using a panel of global and specific subjective scores, a digitized scoring system using the breast retraction assessment (BRA) measurement, and a patient's self-assessment evaluation. As cosmetic results were graded according to severity, the comparison of boost techniques was done using the ordinal logistic regression model. Adjusted odds ratios (OR) and their 95% confidence intervals (CI) are presented. Results: At 36 months of follow-up, there was no significant difference between the two groups with respect to the global subjective cosmetic outcome (OR = 1.40; 95%CI = 0.69-2.85, p = 0.35). Good to excellent scores were observed in 65% of implant patients and 62% of photon/electron patients. At 24 months and beyond, telangiectasia was more severe in the implant group with an OR of 9.64 (95%CI = 4.05-22.92, p < 0.0001) at 36 months. The only variable associated with a worse global cosmetic outcome was the presence of concomitant chemotherapy (OR = 3.87; 95%CI = 1.74-8.62). The BRA value once adjusted for age, concomitant chemotherapy, and boost volume showed a positive association with the boost technique. The BRA value was significantly greater in the implant group (p 0.03). There was no difference in the patient's final self-assessment score between the two groups. Three variables were statistically associated with

  13. Multimodal image registration for the identification of dominant intraprostatic lesion in high-precision radiotherapy treatments.

    PubMed

    Ciardo, Delia; Jereczek-Fossa, Barbara Alicja; Petralia, Giuseppe; Timon, Giorgia; Zerini, Dario; Cambria, Raffaella; Rondi, Elena; Cattani, Federica; Bazani, Alessia; Ricotti, Rosalinda; Garioni, Maria; Maestri, Davide; Marvaso, Giulia; Romanelli, Paola; Riboldi, Marco; Baroni, Guido; Orecchia, Roberto

    2017-08-22

    The integration of computed tomography (CT) and multiparametric magnetic resonance imaging (mpMRI) is a challenging task in high-precision radiotherapy for prostate cancer. A simple methodology for multimodal deformable image registration (DIR) of prostate cancer patients is presented. CT and mpMRI of ten patients were considered. Organs at risk and prostate were contoured on both scans. The dominant intraprostatic lesion was additionally delineated on magnetic resonance imaging. After a preliminary rigid image registration, the voxel intensity of all the segmented structures in both scans except the prostate was increased by a specific amount (a constant additional value, A), in order to enhance the contrast of the main organs influencing its position and shape. Seventy couples of scans were obtained by varying A from 0 to 800 and they were subsequently non-rigidly registered. Quantities derived from image analysis and contour statistics were considered for the tuning of the best performing A. A = 200 resulted the minimum enhancement value required to obtain statistically significant superior registration results. Mean centre of mass distance between corresponding structures decreases from 7.4 mm in rigid registration to 5.3 mm in DIR without enhancement (DIR-0) and to 2.7 mm in DIR with A = 200 (DIR-200). Mean contour distance was 2.5, 1.9 and 0.67 mm in rigid registration, DIR-0 and DIR-200, respectively. In DIR-200 mean contours overlap increases of +13% and +24% with respect to DIR-0 and rigid registration, respectively. Contour propagation according to the vector field resulting from DIR-200 allows the delineation of dominant intraprostatic lesion on CT scan and its use for high-precision radiotherapy treatment planning. Advances in knowledge: We investigated the application of a B-spline, mutual information-based multimodal DIR coupled with a simple, patient-unspecific but efficient contrast enhancement procedure in the pelvic body area, thus

  14. Reinforcing of QA/QC programs in radiotherapy departments in Croatia: Results of treatment planning system verification

    SciTech Connect

    Jurković, Slaven; Švabić, Manda; Diklić, Ana; Smilović Radojčić, Đeni; Dundara, Dea; Kasabašić, Mladen; Ivković, Ana; Faj, Dario

    2013-04-01

    Implementation of advanced techniques in clinical practice can greatly improve the outcome of radiation therapy, but it also makes the process much more complex with a lot of room for errors. An important part of the quality assurance program is verification of treatment planning system (TPS). Dosimetric verifications in anthropomorphic phantom were performed in 4 centers where new systems were installed. A total of 14 tests for 2 photon energies and multigrid superposition algorithms were conducted using the CMS XiO TPS. Evaluation criteria as specified in the International Atomic Energy Agency Technical Reports Series (IAEA TRS) 430 were employed. Results of measurements are grouped according to the placement of the measuring point and the beam energy. The majority of differences between calculated and measured doses in the water-equivalent part of the phantom were in tolerance. Significantly more out-of-tolerance values were observed in “nonwater-equivalent” parts of the phantom, especially for higher-energy photon beams. This survey was done as a part of continuous effort to build up awareness of quality assurance/quality control (QA/QC) importance in the Croatian radiotherapy community. Understanding the limitations of different parts of the various systems used in radiation therapy can systematically improve quality as well.

  15. Spine radiosurgery for the local treatment of spine metastases: Intensity-modulated radiotherapy, image guidance, clinical aspects and future directions

    PubMed Central

    de Moraes, Fabio Ynoe; Taunk, Neil Kanth; Laufer, Ilya; Neves-Junior, Wellington Furtado Pimenta; Hanna, Samir Abdallah; de Andrade Carvalho, Heloisa; Yamada, Yoshiya

    2016-01-01

    Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and nonrandomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future. PMID:26934240

  16. Radiotherapy in Ewing tumors of the vertebrae: Treatment results and local relapse analysis of the Chess 81/86 and EICESS 92 trials

    SciTech Connect

    Schuck, Andreas . E-mail: schuck@uni-muenster.de; Ahrens, Susanne; Schorlemer, Ines von; Kuhlen, Michaela; Paulussen, Michael; Hunold, Andrea; Gosheger, Georg; Winkelmann, Winfried; Dunst, Juergen; Willich, Normann; Juergens, Heribert

    2005-12-01

    Purpose: Treatment results in patients with Ewing tumors of the vertebrae enrolled in the Cooperative Ewing's Sarcoma Study (CESS) 81, 86, and the European Intergroup Cooperative Ewing's Sarcoma Study (EICESS) 92 trials were analyzed with special emphasis on radiation-associated factors. Patients and Methods: A retrospective analysis was performed on 116 patients with primary tumors of the cervical, thoracic, or lumbar vertebrae treated between 1981 and 1999. Furthermore, a relapse analysis was done on those patients who underwent radiotherapy and subsequently had a local recurrence. Results: A total of 64.6% of the patients received definitive radiotherapy; 27.5% of patients had surgery and radiotherapy. Only 4 patients (3.4%) underwent definitive surgery. Twenty-seven patients presented with metastases at diagnosis. 22.4% of the total group developed a local relapse. Among the subgroup with definitive radiotherapy, local recurrence was seen in 17 of 75 patients (22.6%). Event-free survival and survival at 5 years were 47% and 58%, respectively. Of the 14 evaluable patients with a local relapse after radiotherapy, 13 were in-field. No correlation between radiation dose and local control could be found. Conclusion: Surgery with wide resection margins is rarely possible. The results after definitive radiotherapy in vertebral tumors are comparable to those of other tumor sites when definitive radiotherapy is given. Nearly all local relapses after radiotherapy are in-field.

  17. Radiotherapy for the treatment of pain in malignant pleural mesothelioma: a systematic review.

    PubMed

    Macleod, N; Price, A; O'Rourke, N; Fallon, M; Laird, B

    2014-02-01

    Radiotherapy is commonly used to treat pain in malignant pleural mesothelioma (MPM). The purpose of this systematic review is to examine the evidence for this practice. Medline (1946-2013), Embase (1974-2013) and Central (The Cochrane Library Issue 9, 2012) databases were searched. Eligible studies met the following criteria: MPM (histological or radiological diagnosis), radiotherapy given with the intent of improving pain, response rates to radiotherapy reported, dose and fractionation reported and the relationship between radiotherapy and pain response explored. All studies had independent review and were graded according to evidence level. Eight studies met the eligibility criteria. Two studies were prospective single arm phase II studies while the remainder were retrospective case series. All were graded as either Level 2 or Level 3 evidence. Due to marked heterogeneity among studies, quantitative synthesis of results was not possible. No high quality evidence currently exists to support radiotherapy in treating pain in MPM. Studies focusing on clear pain endpoints and improving target delineation are needed. Such studies should also use modern radiotherapy techniques and concentrate on dose escalation.

  18. Computational methods using genome-wide association studies to predict radiotherapy complications and to identify correlative molecular processes

    NASA Astrophysics Data System (ADS)

    Oh, Jung Hun; Kerns, Sarah; Ostrer, Harry; Powell, Simon N.; Rosenstein, Barry; Deasy, Joseph O.

    2017-02-01

    The biological cause of clinically observed variability of normal tissue damage following radiotherapy is poorly understood. We hypothesized that machine/statistical learning methods using single nucleotide polymorphism (SNP)-based genome-wide association studies (GWAS) would identify groups of patients of differing complication risk, and furthermore could be used to identify key biological sources of variability. We developed a novel learning algorithm, called pre-conditioned random forest regression (PRFR), to construct polygenic risk models using hundreds of SNPs, thereby capturing genomic features that confer small differential risk. Predictive models were trained and validated on a cohort of 368 prostate cancer patients for two post-radiotherapy clinical endpoints: late rectal bleeding and erectile dysfunction. The proposed method results in better predictive performance compared with existing computational methods. Gene ontology enrichment analysis and protein-protein interaction network analysis are used to identify key biological processes and proteins that were plausible based on other published studies. In conclusion, we confirm that novel machine learning methods can produce large predictive models (hundreds of SNPs), yielding clinically useful risk stratification models, as well as identifying important underlying biological processes in the radiation damage and tissue repair process. The methods are generally applicable to GWAS data and are not specific to radiotherapy endpoints.

  19. Computational methods using genome-wide association studies to predict radiotherapy complications and to identify correlative molecular processes

    PubMed Central

    Oh, Jung Hun; Kerns, Sarah; Ostrer, Harry; Powell, Simon N.; Rosenstein, Barry; Deasy, Joseph O.

    2017-01-01

    The biological cause of clinically observed variability of normal tissue damage following radiotherapy is poorly understood. We hypothesized that machine/statistical learning methods using single nucleotide polymorphism (SNP)-based genome-wide association studies (GWAS) would identify groups of patients of differing complication risk, and furthermore could be used to identify key biological sources of variability. We developed a novel learning algorithm, called pre-conditioned random forest regression (PRFR), to construct polygenic risk models using hundreds of SNPs, thereby capturing genomic features that confer small differential risk. Predictive models were trained and validated on a cohort of 368 prostate cancer patients for two post-radiotherapy clinical endpoints: late rectal bleeding and erectile dysfunction. The proposed method results in better predictive performance compared with existing computational methods. Gene ontology enrichment analysis and protein-protein interaction network analysis are used to identify key biological processes and proteins that were plausible based on other published studies. In conclusion, we confirm that novel machine learning methods can produce large predictive models (hundreds of SNPs), yielding clinically useful risk stratification models, as well as identifying important underlying biological processes in the radiation damage and tissue repair process. The methods are generally applicable to GWAS data and are not specific to radiotherapy endpoints. PMID:28233873

  20. Treatment planning considerations in contrast-enhanced radiotherapy: energy and beam aperture optimization.

    PubMed

    Garnica-Garza, H M

    2011-01-21

    It has been shown that the use of kilovoltage x-rays in conjunction with a contrast agent incorporated into the tumor can lead to acceptable treatment plans with regard to the absorbed dose distribution produced in the target as well as in the tissue and organs at risk surrounding it. In this work, several key aspects related to the technology and irradiation techniques necessary to clinically implement this treatment modality are addressed by means of Monte Carlo simulation. The Zubal phantom was used to model a prostate radiotherapy treatment, a challenging site due to the depth of the prostate and the presence of bony structures that must be traversed by the x-ray beam on its way to the target. It is assumed that the concentration levels of the enhancing agent present in the tumor are at or below 10 mg per 1 g of tissue. The Monte Carlo code PENELOPE was used to model a commercial x-ray tube having a tungsten target. X-ray energy spectra for several combinations of peak electron energy and added filtration were obtained. For each energy spectrum, a treatment plan was calculated, with the PENELOPE Monte Carlo code, by modeling the irradiation of the patient as 72 independent conformal beams distributed at intervals of 5° around the phantom in order to model a full x-ray source rotation. The Cimmino optimization algorithm was then used to find the optimum beam weight and energy for different treatment strategies. It is shown that for a target dose prescription of 72 Gy covering the whole tumor, the maximum rectal wall and bladder doses are kept below 52 Gy for the largest concentration of contrast agent of 10 mg per 1 g of tissue. It is also shown that concentrations of as little as 5 mg per 1 g of tissue also render dose distributions with excellent sparing of the organs at risk. A treatment strategy to address the presence of non-uniform distributions of the contrast agent in the target is also modeled and discussed.

  1. [Breast lesions of a metastatic melanoma on a radiotherapy territory: Treatment by vemurafenib and carcinologic surgery].

    PubMed

    Fernandez, J; Montaudié, H; Courdi, A; Georgiou, C; Camuzard, O; Chignon-Sicard, B

    2016-02-01

    This article describes the unique case of a female patient who presented distant melanoma metastasis on the breast while having irradiation therapy for breast cancer. This happened eight months after the initial treatment for a melanoma of the back (under the right scapula). Furthermore, this case report demonstrates the efficiency of Vemurafenib® as a treatment for late stage melanomas. The patient was a 47-year-old female that had a superficial spreading melanoma under the right scapula (Breslow 1.02mm) that was treated with 2cm skin excision and sentinel lymph node sampling that was negative. The melanoma was positive for the BRAF600E mutation. One month after this incident, the patient developed breast cancer that was treated with conservative surgery and radiotherapy. Three months after the end of the irradiation treatment, she developed multiple melanoma metastasis on the skin of the breast. Our multidisciplinary team decided to initiate a treatment with vemurafenib. The patient showed an excellent response, so the surgical team completed the treatment with a radical mastectomy and immediate reconstruction with a pedicled latissimus dorsi flap. The histologic report of the mastectomy specimen showed no sign of melanocytic proliferation, that demonstrates the efficacy of vemurafenib. The patient showed no relapse after two years of follow-up. The speed of development and location of cutaneous metastases in this case brought us to think about the effects of radiation therapy on the skin. Radiation therapy causes acute complications (radiodermatitis) by cellular and molecular mechanisms. Moreover, depressed immunity is found after irradiation. Association of these mecanisms could explain the appearance of these metastases in irradiation field. The efficiency of vemurafenib found in our case is consistent with what is described in literature, especially with the improvement in median overall survival. This case demonstrates a unique case of distant melanoma

  2. [{sup 18}FDG] PET-CT-Based Intensity-Modulated Radiotherapy Treatment Planning of Head and Neck Cancer

    SciTech Connect

    El-Bassiouni, Mazen; Ciernik, I. Frank Davis, J. Bernard; El-Attar, Inas; Reiner, Beatrice; Burger, Cyrill; Goerres, Gerhard W.; Studer, Gabriela M.

    2007-09-01

    Purpose: To define the best threshold for tumor volume delineation of the (18) fluoro-2-deoxy-glucose positron emission tomography ({sup 18}FDG-PET) signal for radiotherapy treatment planning of intensity-modulated radiotherapy (IMRT) in head and neck cancer. Methods and Materials: In 25 patients with head-and-neck cancer, CT-based gross tumor volume (GTV{sub CT}) was delineated. After PET-CT image fusion, window level (L) was adapted to best fit the GTV{sub CT}, and GTV{sub PET} was delineated. Tumor maximum (S) and background uptake (B) were measured, and the threshold of the background-subtracted tumor maximum uptake (THR) was used for PET signal segmentation. Gross tumor volumes were expanded to planning target volumes (PTVs) and analyzed. Results: The mean value of S was 40 kBq/mL, S/B ratio was 16, and THR was 26%. The THR correlated with S (r = -0.752), but no correlation between THR and the S/B ratio was seen (r = -0.382). In 77% of cases, S was >30 kBq/mL, and in 23% it was {<=}30 kBq/mL, with a mean THR of 21.4% and 41.6%, respectively (p < 0.001). Using PTV{sub PET} in radiotherapy treatment planning resulted in a reduced PTV in 72% of cases, while covering 88.2% of GTV{sub CT}, comparable to the percentage of GTV{sub PET} covered by PTV{sub CT} (p = 0.15). Conclusions: A case-specific PET signal threshold is optimal in PET-based radiotherapy treatment planning. Signal gating using a THR of 20% in tumors with S >30% {+-} 1.6% kBq/mL and 40% in tumors with S {<=}30% {+-} 1.6% kBq/mL is suitable.

  3. Calcium, oxidative stress and connexin channels, a harmonious orchestra directing the response to radiotherapy treatment?

    PubMed

    Decrock, Elke; Hoorelbeke, Delphine; Ramadan, Raghda; Delvaeye, Tinneke; De Bock, Marijke; Wang, Nan; Krysko, Dmitri V; Baatout, Sarah; Bultynck, Geert; Aerts, An; Vinken, Mathieu; Leybaert, Luc

    2017-02-11

    Although radiotherapy is commonly used to treat cancer, its beneficial outcome is frequently hampered by the radiation resistance of tumor cells and adverse reactions in normal tissues. Mechanisms of cell-to-cell communication and how intercellular signals are translated into cellular responses, have become topics of intense investigation, particularly within the field of radiobiology. A substantial amount of evidence is available demonstrating that both gap junctional and paracrine communication pathways can propagate radiation-induced biological effects at the intercellular level, commonly referred to as radiation-induced bystander effects (RIBE). Multiple molecular signaling mechanisms involving oxidative stress, kinases, inflammatory molecules, and Ca(2+) are postulated to contribute to RIBE. Ca(2+) is a highly versatile and ubiquitous second messenger that regulates diverse cellular processes via the interaction with various signaling cascades. It furthermore provides a fast system for the dissemination of information at the intercellular level. Channels formed by transmembrane connexin (Cx) proteins, i.e. hemichannels and gap junction channels, can mediate the cell-to-cell propagation of increases in intracellular Ca(2+) by ministering paracrine and direct cell-cell communication, respectively. We here review current knowledge on radiation-induced signaling mechanisms in irradiated and bystander cells, particularly focusing on the contribution of oxidative stress, Ca(2+) and Cx channels. By illustrating the tight interplay between these different partners, we provide a conceptual framework for intercellular Ca(2+) signaling as a key player in modulating the RIBE and the overall response to radiation.

  4. A geometric atlas to predict lung tumor shrinkage for radiotherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Zhang, Pengpeng; Rimner, Andreas; Yorke, Ellen; Hu, Yu-Chi; Kuo, Licheng; Apte, Aditya; Lockney, Natalie; Jackson, Andrew; Mageras, Gig; Deasy, Joseph O.

    2017-02-01

    To develop a geometric atlas that can predict tumor shrinkage and guide treatment planning for non-small-cell lung cancer. To evaluate the impact of the shrinkage atlas on the ability of tumor dose escalation. The creation of a geometric atlas included twelve patients with lung cancer who underwent both planning CT and weekly CBCT for radiotherapy planning and delivery. The shrinkage pattern from the original pretreatment to the residual posttreatment tumor was modeled using a principal component analysis, and used for predicting the spatial distribution of the residual tumor. A predictive map was generated by unifying predictions from each individual patient in the atlas, followed by correction for the tumor’s surrounding tissue distribution. Sensitivity, specificity, and accuracy of the predictive model for classifying voxels inside the original gross tumor volume were evaluated. In addition, a retrospective study of predictive treatment planning (PTP) escalated dose to the predicted residual tumor while maintaining the same level of predicted complication rates for a clinical plan delivering uniform dose to the entire tumor. The effect of uncertainty on the predictive model’s ability to escalate dose was also evaluated. The sensitivity, specificity and accuracy of the predictive model were 0.73, 0.76, and 0.74, respectively. The area under the receiver operating characteristic curve for voxel classification was 0.87. The Dice coefficient and mean surface distance between the predicted and actual residual tumor averaged 0.75, and 1.6 mm, respectively. The PTP approach allowed elevation of PTV D95 and mean dose to the actual residual tumor by 6.5 Gy and 10.4 Gy, respectively, relative to the clinical uniform dose approach. A geometric atlas can provide useful information on the distribution of resistant tumors and effectively guide dose escalation to the tumor without compromising the organs at risk complications. The atlas can be further refined by using

  5. Postoperative radiotherapy for oral cavity cancers: Impact of anatomic subsite on treatment outcome

    SciTech Connect

    Zelefsky, M.J.; Harrison, L.B.; Fass, D.E.; Armstrong, J.; Spiro, R.H.; Shah, J.P.; Strong, E.W. )

    1990-11-01

    We have retrospectively reviewed the treatment results of postoperative radiotherapy (RT) for advanced oral cavity cancers. The purpose of this study was to determine the impact of anatomic subsite on the results of treatment. Between 1975 and 1985, 51 patients with squamous cell carcinoma of the oral tongue (OT = 29 patients) and floor of mouth (FOM = 22 patients) were treated with combined surgery plus RT. All had an indication(s) for RT including advanced primary disease (T3 or T4) (29 patients), close or positive margins (34 patients), and multiple positive neck nodes and/or extracapsular extension (41 patients). With a median follow-up of 6 years, the 5-year actuarial local control rate was 74% and the rate of distant metastasis (DM) was 34%. Despite the similar T stage, margin status and median RT dose, the 5-year actuarial local failure rate was 38% for OT vs. 11% for FOM (p = 0.03). Furthermore, the median survival after recurrence was 9 months for OT and 40 months for FOM (p = 0.02). At 5 years the determinate survival for both sites was (55%), and the likelihood of developing a second malignancy was 31%. The likelihood of developing DM was 50% for FOM (N0-N1 = 3 of 12, N2-N3 = 8 of 10) and 21% for OT (N0-N1 = 4 of 21, N2-N3 = 1 of 8). This study highlights significant differences between FOM and OT cancers in response to combined surgery and RT. Future strategies should be directed at the enhancement of local control for OT and better systemic therapy for those with advanced N-stage FOM.

  6. sup 211 At-methylene blue for targeted radiotherapy of human melanoma xenografts: Treatment of micrometastases

    SciTech Connect

    Link, E.M.; Carpenter, R.N. )

    1990-05-15

    Treatment of micrometastases of HX34 human melanoma grown as xenografts in nude mice represents an advanced stage of preclinical investigations concerning targeted radiotherapy of this neoplasm using 3,7-(dimethylamino)phenazathionium chloride methylene blue (MTB) labeled with astatine-211 (211At) (alpha-particle emitter). The therapeutic effectiveness of 211At-MTB administered i.v. was determined by a lung colony assay combined with a search for metastases to organs other than the lungs. A single dose of 211At-MTB lowered the HX34 cell surviving fraction in lungs to below 10% almost independently of the time interval between cell inoculation and radioisotope injection and of 211At-MTB radioactivity within its investigated range. Radiation dose and the time of its administration did, however, influence the size of lung colonies. In contrast, the efficacy of 211At-MTB treatment as assessed by both surviving fraction and colony size was significantly dependent on a number of HX34 cells inoculated initially into mice. These results are explained by a short range of alpha-particles emitted by 211At and a mechanism of growth of lung colonies from tumor cells circulating with blood and blocking lung capillaries. Metastases in organs other than lungs and characteristic of control animals were not found in mice treated with 211At-MTB. The high therapeutic efficacy achieved proved that 211At-MTB is a very efficient scavenger of single melanoma cells distributed through blood and micrometastases with sizes below the limit of clinical detection.

  7. Accuracy of Breath-hold CT in Treatment Planning for Lung Stereotactic Ablative Radiotherapy

    PubMed Central

    Martel, Charles; Campeau, Marie-Pierre; Filion, Édith; Roberge, David; Bahig, Houda; Vu, Toni; Lambert, Louise; Boudam, Karim; Carrier, Jean-Francois

    2014-01-01

    Purpose: The objectives of this study are (1) to measure concordance of tumor position on breath-hold (BH) computed tomography (CT) scans relative to the natural tumor path during free breathing (FB) and (2) to evaluate the benefits of the breathing monitoring device Abches (Apex Medical, Tokyo) for stereotactic ablative radiotherapy (SABR) treatment planning. Methods: In 53 lung cancer patients treated with CyberKnife™ robotic radiosurgery system, FB four-dimensional computerized tomography (4DCT) and end-expiration (EE) BH CT images were obtained. Extent of natural tumor motion was assessed with rigid registration derived from end-inspiration (EI) and EE phases of the 4DCT. Tumor displacement in BH scans relative to the natural tumor path was measured relative to the EE 4DCT phase. Results: Mean tumor motion (+/- 1 SD) during natural FB was 1 ± 1 mm, 2 ± 2 mm, and 6 ± 6 mm in medio-lateral, anterior-posterior, and cranio-caudal directions, respectively. Tumor position on BH CT scan was closer to EE than EI 4DCT phase for 35/53 patients (66%). Difference of BH tumor position vs. EE state was 4 ± 3 mm. Gross tumor displacements perpendicular to natural tumor path were as great as 11 mm (anterior-posterior) and were seen with or without the breathing monitoring device. Conclusion: Tumor position during BH CT may not accurately correspond to positions observed on FB 4DCT. Hence, accurate and custom 4D analysis for each individual patient is recommended for treatment planning, especially those involving BH acquisitions. PMID:28003937

  8. Radiotherapy Is Associated With Improved Survival in Adjuvant and Palliative Treatment of Extrahepatic Cholangiocarcinomas

    SciTech Connect

    Shinohara, Eric T. Mitra, Nandita; Guo Mengye; Metz, James M.

    2009-07-15

    Purpose: Extrahepatic cholangiocarcinomas (EHC) are rare tumors of the biliary tree because of their low incidence, large randomized studies examining radiotherapy (RT) for EHC have not been performed. The purpose of this study was to examine the role of adjuvant and palliative RT in the treatment of EHC in a large patient population. Methods and Materials: This was a retrospective analysis of 4,758 patients with EHC collected from the Surveillance, Epidemiology, and End Results database. The primary endpoint was overall survival. Results: Patients underwent surgery (28.8%), RT (10.0%), surgery and RT (14.7%), or no RT or surgery (46.4%). The median age of the patient population was 73 years (range, 23-104), 52.5% were men, and 80.7% were white. The median overall survival time was 16 months (95% confidence interval [CI] 15-17), 9 months (95% CI 9-11), 9 months (95% CI 9-10), and 4 months (95% CI 3-4) for surgery and RT, surgery, RT, and no RT or surgery, respectively. The overall survival was significantly different between the surgery and surgery and RT groups (p < .0001) and RT and no RT or surgery groups (p < .0001) on the log-rank test. The propensity score-adjusted analyses of surgery and RT vs. surgery (hazard ratio, 0.94; 95% CI, 0.84-1.05) were not significantly different, but that for RT vs. no RT or surgery (hazard ratio, 0.61; 95% CI, 0.54-0.70) was significantly different. Conclusion: These results suggest that palliative RT prolongs survival in patients with EHC. The benefit associated with surgery and RT was significant on univariate analysis but not after controlling for potential confounders using the propensity score. Future studies should evaluate the addition of chemotherapy and biologic agents for the treatment of EHC.

  9. A geometric atlas to predict lung tumor shrinkage for radiotherapy treatment planning.

    PubMed

    Zhang, Pengpeng; Rimner, Andreas; Yorke, Ellen; Hu, Yu-Chi; Kuo, Licheng; Apte, Aditya; Lockney, Natalie; Jackson, Andrew; Mageras, Gig; Deasy, Joseph O

    2017-01-10

    To develop a geometric atlas that can predict tumor shrinkage and guide treatment planning for non-small-cell lung cancer. To evaluate the impact of the shrinkage atlas on the ability of tumor dose escalation. The creation of a geometric atlas included twelve patients with lung cancer who underwent both planning CT and weekly CBCT for radiotherapy planning and delivery. The shrinkage pattern from the original pretreatment to the residual posttreatment tumor was modeled using a principal component analysis, and used for predicting the spatial distribution of the residual tumor. A predictive map was generated by unifying predictions from each individual patient in the atlas, followed by correction for the tumor's surrounding tissue distribution. Sensitivity, specificity, and accuracy of the predictive model for classifying voxels inside the original gross tumor volume were evaluated. In addition, a retrospective study of predictive treatment planning (PTP) escalated dose to the predicted residual tumor while maintaining the same level of predicted complication rates for a clinical plan delivering uniform dose to the entire tumor. The effect of uncertainty on the predictive model's ability to escalate dose was also evaluated. The sensitivity, specificity and accuracy of the predictive model were 0.73, 0.76, and 0.74, respectively. The area under the receiver operating characteristic curve for voxel classification was 0.87. The Dice coefficient and mean surface distance between the predicted and actual residual tumor averaged 0.75, and 1.6 mm, respectively. The PTP approach allowed elevation of PTV D95 and mean dose to the actual residual tumor by 6.5 Gy and 10.4 Gy, respectively, relative to the clinical uniform dose approach. A geometric atlas can provide useful information on the distribution of resistant tumors and effectively guide dose escalation to the tumor without compromising the organs at risk complications. The atlas can be further refined by using more

  10. Effectiveness of Carbon Ion Radiotherapy in the Treatment of Skull-Base Chordomas

    SciTech Connect

    Schulz-Ertner, Daniela . E-mail: Daniela.Ertner@med.uni-heidelberg.de; Karger, Christian P.; Feuerhake, Alexandra; Nikoghosyan, Anna; Combs, Stephanie E.; Jaekel, Oliver; Edler, Lutz; Scholz, Michael; Debus, Juergen

    2007-06-01

    Purpose: The aim of this study was to evaluate the effectiveness and toxicity of carbon ion radiotherapy in chordomas of the skull base. Methods and Materials: Between November 1998 and July 2005, a total of 96 patients with chordomas of the skull base have been treated with carbon ion radiation therapy (RT) using the raster scan technique at the Gesellschaft fuer Schwerionenforschung (GSI) in Darmstadt, Germany. All patients had gross residual tumors. Median total dose was 60 CGE (range, 60-70 CGE) delivered in 20 fractions within 3 weeks. Local control and overall survival rates were calculated using the Kaplan-Meier method. Toxicity was assessed according to the Common Terminology Criteria (CTCAE v.3.0) and the Radiation Therapy Oncology Group (RTOG) / European Organization for Research and Treatment of Cancer (EORTC) score. Results: Mean follow-up was 31 months (range, 3-91 months). Fifteen patients developed local recurrences after carbon ion RT. The actuarial local control rates were 80.6% and 70.0% at 3 and 5 years, respectively. Target doses in excess of 60 CGE and primary tumor status were associated with higher local control rates. Overall survival was 91.8% and 88.5% at 3 and 5 years, respectively. Late toxicity consisted of optic nerve neuropathy RTOG/EORTC Grade 3 in 4.1% of the patients and necrosis of a fat plomb in 1 patient. Minor temporal lobe injury (RTOG/EORTC Grade 1-2) occurred in 7 patients (7.2%). Conclusions: Carbon ion RT offers an effective treatment option for skull-base chordomas with acceptable toxicity. Doses in excess of 75 CGE with 2 CGE per fraction are likely to increase local control probability.

  11. Multiple two-dimensional versus three-dimensional PTV definition in treatment planning for conformal radiotherapy.

    PubMed

    Stroom, J C; Korevaar, G A; Koper, P C; Visser, A G; Heijmen, B J

    1998-06-01

    To demonstrate the need for a fully three-dimensional (3D) computerized expansion of the gross tumour volume (GTV) or clinical target volume (CTV), as delineated by the radiation oncologist on CT slices, to obtain the proper planning target volume (PTV) for treatment planning according to the ICRU-50 recommendations. For 10 prostate cancer patients two PTVs have been determined by expansion of the GTV with a 1.5 cm margin, i.e. a 3D PTV and a multiple 2D PTV. The former was obtained by automatically adding the margin while accounting in 3D for GTV contour differences in neighbouring slices. The latter was generated by automatically adding the 1.5 cm margin to the GTV in each CT slice separately; the resulting PTV is a computer simulation of the PTV that a radiation oncologist would obtain with (the still common) manual contouring in CT slices. For each patient the two PTVs were compared to assess the deviations of the multiple 2D PTV from the 3D PTV. For both PTVs conformal plans were designed using a three-field technique with fixed block margins. For each patient dose-volume histograms and tumour control probabilities (TCPs) of the (correct) 3D PTV were calculated, both for the plan designed for this PTV and for the treatment plan based on the (deviating) 2D PTV. Depending on the shape of the GTV, multiple 2D PTV generation could locally result in a 1 cm underestimation of the GTV-to-PTV margin. The deviations occurred predominantly in the cranio-caudal direction at locations where the GTV contour shape varies significantly from slice to slice. This could lead to serious underdosage and to a TCP decrease of up to 15%. A full 3D GTV-to-PTV expansion should be applied in conformal radiotherapy to avoid underdosage.

  12. Malignant obstructive jaundice: treatment with external-beam and intracavitary radiotherapy

    SciTech Connect

    Johnson, D.W.; Safai, C.; Goffinet, D.R.

    1985-02-01

    Eleven patients with obstructive jaundice from unresectable cholangiocarcinoma, metastatic porta hepatis adenopathy, or direct compression from a pancreatic malignancy were treated at the Stanford University Medical Center from 1978-1983 with an external drainage procedure followed by high-dose external-beam radiotherapy and by an intracavitary boost to the site of obstruction with Iridium/sup 192/ (Ir/sup 192/). A median dose of 5000 cGy was delivered with 4-6 Mv photons to the tumor bed and regional lymphatics in 9 patients, 1 patient received 2100 cGy to the liver in accelerated fractions because of extensive intrahepatic disease, and 1 patient received 7000 equivalent cGy to his pancreatic tumor bed and regional lymphatics with neon heavy particles. An Ir/sup 192/ wire source later delivered a 3100-10,647 cGy boost to the site of biliary obstruction in each patient, for a mean combined dose of 10,202 cGy to a point 5 mm from the line source. Few acute complications were noted, but 3/11 patients (27%) subsequently developed upper gastrointestinal bleeding from duodenitis or frank duodenal ulceration 4 weeks, 4 months, and 7.5 months following treatment. Eight patients died - 5 with local recurrence +/- distant metastasis, 2 with sepsis, and 1 with widespread systemic metastasis. Autopsies revealed no evidence of biliary tree obstruction in 3/3 patients. Evolution of radiation treatment technqiues for biliary obstruction in the literature is reviewed. High-dose external-beam therapy followed by high-dose Ir/sup 192/ intracavitary boost is well tolerated and provides significant palliation.

  13. Megavoltage conebeam CT cine as final verification of treatment plan in lung stereotactic body radiotherapy.

    PubMed

    Kudithipudi, Vijay; Gayou, Olivier; Colonias, Athanasios

    2016-06-01

    To analyse the clinical impact of megavoltage conebeam computed tomography (MV-CBCT) cine on internal target volume (ITV) coverage in lung stereotactic body radiotherapy (SBRT). One hundred and six patients received lung SBRT. All underwent 4D computed tomography simulation followed by treatment via image guided 3D conformal or intensity modulated radiation. Prior to SBRT, all patients underwent MV-CBCT cine, in which raw projections are displayed as beam's-eye-view fluoroscopic series with the planning target volume (PTV) projected onto each image, enabling verification of tumour motion relative to the PTV and assessment of adequacy of treatment margin. Megavoltage conebeam computed tomography cine was completed 1-2 days prior to SBRT. Four patients (3.8%) had insufficient ITV coverage inferiorly at cine review. All four plans were changed by adding 5 mm on the PTV margin inferiorly. The mean change in PTV volumes was 3.9 cubic centimetres (cc) (range 1.85-6.32 cc). Repeat cine was performed after plan modification to ensure adequate PTV coverage in the modified plans. PTV margin was adequate in the majority of patients with this technique. MV-CBCT cine did show insufficient coverage in a small subset of patients. Insufficient PTV margins may be a function of 4D CT simulation inadequacies or deficiencies in visualizing the ITV inferior border in the full-inhale phase. MV-CBCT cine is a valuable tool for final verification of PTV margins. © 2016 The Royal Australian and New Zealand College of Radiologists.

  14. Abnormal Nuclear Variations in Response to Radiotherapy- As a Tool in Treatment Planning and Assessment of Prognosis.

    PubMed

    Ravi, Kumar Satish; Naithani, Manisha; Kaur, Sohinder; Reddy, K S; Pasi, Rachna

    2016-08-01

    The treatment approaches for oral squamous cell carcinoma (OSCC) include single management with surgery, radiotherapy, along with chemotherapy or various combinations of these modalities. The estimation of radio sensitivity of individual tumours is essential for planning the optimum radiation schedule for each patient. Assessment of radiation induced histo morphological changes in the nucleus is a known marker of radiosensitivity. The aim of this study was to establish the relationship between nuclear changes with radiation dose and to investigate the prospect of utilizing them as an assay to predict tumour response to radiotherapy in oral cancers. The present study included 50 patients (age range of 30-65yrs) with histopathologically confirmed squamous cell carcinoma of oral mucosa and being treated by radiotherapy alone with a radiation dose schedule of 4, 14, 24 and 60 Gy respectively at 2(nd), 7(th), 12(th) and 30(th) day. From the included patients, smear of the buccal mucosa was collected and was air dried and fixed with methanol. The Nuclear changes of Micronucleus (MN), Nuclear Budding (NB) and Multinucleation (MNU) were evaluated under the bright field microscopy after staining with Giemsa and May-Grunwald's stain. Out of the 50, 37(74%) were males and 13(26%) were females (Ratio 3:1). The mean percentage increase of MN and MNU were found to be statistically significant (p=0.001) when compared with pre-treatment day. Similar findings were seen with NB, except between pretreatment and after 14 Gy (p-0.110). In the present study the measurement of relative increment index done in respect to all nuclear abnormalities show a sustained increase with increasing dosage of radiation. The present study, was undertaken to explore the possibility of establishing a relationship between the frequencies of nuclear abnormalities in patients with oral cancer with applied dosage and duration of radiotherapy. The progressive increase in Micronucleus and Multinucleation

  15. SU-E-T-379: Concave Approximations of Target Volume Dose Metrics for Intensity- Modulated Radiotherapy Treatment Planning

    SciTech Connect

    Xie, Y; Chen, Y; Wickerhauser, M; Deasy, J

    2014-06-01

    Purpose: The widely used treatment plan metric Dx (mimimum dose to the hottest x% by volume of the target volume) is simple to interpret and use, but is computationally poorly behaved (non-convex), this impedes its use in computationally efficient intensity-modulated radiotherapy (IMRT) treatment planning algorithms. We therefore searched for surrogate metrics that are concave, computationally efficient, and accurately correlated to Dx values in IMRT treatment plans. Methods: To find concave surrogates of D95—and more generally, Dx values with variable x values—we tested equations containing one or two generalized equivalent uniform dose (gEUD) functions. Fits were obtained by varying gEUD ‘a’ parameter values, as well as the linear equation coefficients. Fitting was performed using a dataset of dose-volume histograms from 498 de-identified head and neck IMRT treatment plans. Fit characteristics were tested using a crossvalidation process. Reported root-mean-square error values were averaged over the cross-validation shuffles. Results: As expected, the two-gEUD formula provided a superior fit, compared to the single-gEUD formula. The best approximation uses two gEUD terms: 16.25 x gEUD[a=0.45] – 15.30 x gEUD[a=1.75] – 0.69. The average root-mean-square error on repeated (70/30) cross validation was 0.94 Gy. In addition, a formula was found that reasonably approximates Dx for x between 80% and 96%. Conclusion: A simple concave function using two gEUD terms was found that correlates well with PTV D95s for these head and neck treatment plans. More generally, a formula was found that represents well the Dx for x values from 80% to 96%, thus providing a computationally efficient formula for use in treatment planning optimization. The formula may need to be adjusted for other institutions with different treatment planning protocols. We conclude that the strategy of replacing Dx values with gEUD-based formulas is promising.

  16. Prolongation of overall treatment time as a cause of treatment failure in early breast cancer: An analysis of the UK START (Standardisation of Breast Radiotherapy) trials of radiotherapy fractionation.

    PubMed

    Haviland, Joanne S; Bentzen, Søren M; Bliss, Judith M; Yarnold, John R

    2016-12-01

    Tests of tumour treatment time effect in patients prescribed post-operative radiotherapy for early breast cancer have focussed on time to start of radiotherapy rather than overall treatment time. The START randomised trials of radiotherapy fractionation provide an opportunity to directly estimate the effect of treatment acceleration. Between 1986 and 2002, a total of 5861 women with early breast cancer were recruited into the UK START pilot (START-P), START-A and START-B randomised trials. START-P and START-A tested 13 fractions of 3.0-3.3Gy against 25 fractions of 2.0Gy with a fixed treatment duration of 5weeks for all schedules; START-B tested 15 fractions of 2.67Gy in 3weeks against 25 fractions of 2.0Gy over 5weeks. Estimates of the effect of length of treatment for local-regional relapse and for a measure of late normal tissue effects (change in photographic breast appearance, for patients following breast conserving surgery) were obtained from Cox proportional hazards regression analyses stratified according to trial. At a median follow-up of 10years, 444/5831 (7.6%) patients with data available had a local-regional relapse, and 1135/3185 (35.6%) had mild or marked change in photographic breast appearance by 5years. Adjusting for prognostic factors, the estimate of the overall treatment time effect for local-regional relapse was 0.60Gy/day (95%CI 0.10 to 1.18Gy/day, p=0.02), and 0.14Gy/day (95%CI -0.09 to 0.34Gy/day, p=0.29) for change in photographic breast appearance. Combined analysis of the START trials generates the hypothesis that overall treatment time is a significant determinant of local cancer control after adjuvant whole breast radiotherapy, with approximately 0.6Gy per day 'wasted' in compensating for tumour cell proliferation. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  17. Radiotherapy Treatment Plans With RapidArc for Prostate Cancer Involving Seminal Vesicles and Lymph Nodes

    SciTech Connect

    Yoo, Sua; Wu, Q. Jackie; Lee, W. Robert; Yin Fangfang

    2010-03-01

    Purpose: Dosimetric results and treatment delivery efficiency of RapidArc plans to those of conventional intensity-modulated radiotherapy (IMRT) plans were compared using the Eclipse treatment planning system for high-risk prostate cancer. Materials and Methods: This study included 10 patients. The primary planning target volume (PTV{sub P}) contained prostate, seminal vesicles, and pelvic lymph nodes with a margin. The boost PTV (PTV{sub B}) contained prostate and seminal vesicles with a margin. The total prescription dose was 75.6 Gy (46.8 Gy to PTV{sub P} and an additional 28.8 Gy to PTV{sub B}; 1.8 Gy/fraction). Three plans were generated for each PTV: Multiple-field IMRT, one-arc RapidArc (1ARC), and two-arc RapidArc (2ARC). Results: In the primary IMRT with PTV{sub P}, average mean doses to bladder, rectum and small bowel were lower by 5.9%, 7.7% and 4.3%, respectively, than in the primary 1ARC and by 3.6%, 4.8% and 3.1%, respectively, than in the primary 2ARC. In the boost IMRT with PTV{sub B}, average mean doses to bladder and rectum were lower by 2.6% and 4.8% than with the boost 1ARC and were higher by 0.6% and 0.2% than with the boost 2ARC. Integral doses were 7% to 9% higher with RapidArc than with IMRT for both primary and boost plans. Treatment delivery time was reduced by 2-7 minutes using RapidArc. Conclusion: For PTVs including prostate, seminal vesicles, and lymph nodes, IMRT performed better in dose sparing for bladder, rectum, and small bowel than did RapidArc. For PTVs including prostate and seminal vesicles, RapidArc with two arcs provided plans comparable to those for IMRT. The treatment delivery is more efficient with RapidArc.

  18. Radiotherapy DICOM packet sniffing.

    PubMed

    Ackerly, T; Gesoand, M; Smith, R

    2008-09-01

    The Digital Imaging and Communications in Medicine (DICOM) standard is meant to allow communication of medical images between equipment provided by different vendors, but when two applications do not interact correctly in a multi-vendor environment it is often first necessary to demonstrate non-compliance of either the sender or the receiver before a resolution to the problem can be progressed. Sometimes the only way to do this is to monitor the network communication between the two applications to find out which one is not complying with the DICOM standard. Packet sniffing is a technique of network traffic analysis by passive observation of all information transiting a point on the network, regardless of the specified sender or receiver. DICOM packet sniffing traps and interprets the network communication between two DICOM applications to determine which is non compliant. This is illustrated with reference to three examples, a radiotherapy planning system unable to receive CT data from a particular CT scanner, a radiotherapy simulator unable to print correctly on a DICOM printer, and a PACS unable to respond when queried about what images it has in its archive by a radiotherapy treatment planning system. Additionally in this work it has been proven that it is feasible to extract DICOM images from the intercepted network data. This process can be applied to determine the cause of a DICOM image being rendered differently by the sender and the receiver.

  19. Role of imaging and biopsy to assess local recurrence after definitive treatment for prostate carcinoma (surgery, radiotherapy, cryotherapy, HIFU).

    PubMed

    Martino, Pasquale; Scattoni, Vincenzo; Galosi, Andrea B; Consonni, Paolo; Trombetta, Carlo; Palazzo, Silvano; Maccagnano, Carmen; Liguori, Giovanni; Valentino, Massimo; Battaglia, Michele; Barozzi, Libero

    2011-10-01

    Defining the site of recurrent disease early after definitive treatment for a localized prostate cancer is a critical issue as it may greatly influence the subsequent therapeutic strategy or patient management. A systematic review of the literature was performed by searching Medline from January 1995 up to January 2011. Electronic searches were limited to the English language, and the keywords prostate cancer, radiotherapy [RT], high intensity focused ultrasound [HIFU], cryotherapy [CRIO], transrectal ultrasound [TRUS], magnetic resonance [MRI], PET/TC, and prostate biopsy were used. Despite the fact that diagnosis of a local recurrence is based on PSA values and kinetics, imaging by means of different techniques may be a prerequisite for effective disease management. Unfortunately, prostate cancer local recurrences are very difficult to detect by TRUS and conventional imaging that have shown limited accuracy at least at early stages. On the contrary, functional and molecular imaging such as dynamic contrast-enhanced MRI (DCE-MRI), and diffusion-weighted imaging (DWI), offers the possibility of imaging molecular or cellular processes of individual tumors. Recently, PET/CT, using 11C-choline, 18F-fluorocholine or 11C-acetate has been successfully proposed in detecting local recurrences as well as distant metastases. Nevertheless, in controversial cases, it is necessary to perform a biopsy of the prostatic fossa or a biopsy of the prostate to assess the presence of a local recurrence under guidance of MRI or TRUS findings. It is likely that imaging will be extensively used in the future to detect and localize prostate cancer local recurrences before salvage treatment.

  20. Clinical quality standards for radiotherapy

    PubMed Central

    2012-01-01

    Aim of the study The technological progress that is currently being witnessed in the areas of diagnostic imaging, treatment planning systems and therapeutic equipment has caused radiotherapy to become a high-tech and interdisciplinary domain involving staff of various backgrounds. This allows steady improvement in therapy results, but at the same time makes the diagnostic, imaging and therapeutic processes more complex and complicated, requiring every stage of those processes to be planned, organized, controlled and improved so as to assure high quality of services provided. The aim of this paper is to present clinical quality standards for radiotherapy as developed by the author. Material and methods In order to develop the quality standards, a comparative analysis was performed between European and Polish legal acts adopted in the period of 1980-2006 and the universal industrial ISO 9001:2008 standard, defining requirements for quality management systems, and relevant articles published in 1984-2009 were reviewed, including applicable guidelines and recommendations of American, international, European and Polish bodies, such as the American Association of Physicists in Medicine (AAPM), the European Society for Radiotherapy & Oncology (ESTRO), the International Atomic Energy Agency (IAEA), and the Organisation of European Cancer Institutes (OECI) on quality assurance and management in radiotherapy. Results As a result, 352 quality standards for radiotherapy were developed and categorized into the following three groups: 1 – organizational standards; 2 – physico-technical standards and 3 – clinical standards. Conclusion Proposed clinical quality standards for radiotherapy can be used by any institution using ionizing radiation for medical purposes. However, standards are of value only if they are implemented, reviewed, audited and improved, and if there is a clear mechanism in place to monitor and address failure to meet agreed standards. PMID:23788854

  1. Atypical and malignant meningiomas: Considerations for treatment and efficacy of radiotherapy.

    PubMed

    Cain, Sarah A; Smoll, Nicolas R; Van Heerden, J; Tsui, Alpha; Drummond, Katharine J

    2015-11-01

    The purpose of this study was to add to the current body of literature which is aimed at establishing the role of postoperative adjuvant radiotherapy (RT) in the treatment of atypical and malignant meningiomas. Meningiomas are the most frequently reported primary intracranial tumours, accounting for more than 35%. The majority of meningiomas are benign, with atypical and malignant tumours accounting for only 6-18%. Utilising a prospective multi-institutional database, we retrospectively reviewed 67 patients with documented World Health Organisation (WHO) Grade II/III meningiomas, diagnosed between 1989 and 2012 and resected at two major Australian hospitals. Nine patients were excluded and the remaining 58 were analysed. The patient demographics, tumour characteristics, surgical details and adjuvant therapy were retrieved. Kaplan-Meier curves were used to compare the survival of patients treated with RT versus surgery alone. The 3 year progression free survival (PFS) and overall survival (OS) were 44 and 76% for the entire cohort, respectively. Of the patients who had gross total resections, 42% had 3 years PFS and 77% had 3 years OS, which was not significantly different from those with subtotal resection. The overall median survival was 11.0 years, 12.2 for atypical and 1.6 for malignant meningiomas. The patients with malignant meningiomas were 14 times as likely to receive RT as the patients with atypical meningiomas. The patients who received RT had a 3 year PFS of 63% compared to 40% in those who did not receive radiation. The 3 year OS was 31% higher for females than males. Histopathological progression was noted in 17% of our cohort. This study reinforces a number of important factors that should be considered when treating patients presenting with WHO Grade II and III meningiomas, including sex, potential for grade progression, and the lack of evidence for adjuvant RT and the timing thereof. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Biochemical Imaging of Gliomas Using MR Spectroscopic Imaging for Radiotherapy Treatment Planning

    NASA Astrophysics Data System (ADS)

    Heikal, Amr Ahmed

    This thesis discusses the main obstacles facing wide clinical implementation of magnetic resonance spectroscopic imaging (MRSI) as a tumor delineation tool for radiotherapy treatment planning, particularly for gliomas. These main obstacles are identified as 1. observer bias and poor interpretational reproducibility of the results of MRSI scans, and 2. the long scan times required to conduct MRSI scans. An examination of an existing user-independent MRSI tumor delineation technique known as the choline-to-NAA index (CNI) is conducted to assess its utility in providing a tool for reproducible interpretation of MRSI results. While working with spatial resolutions typically twice those on which the CNI model was originally designed, a region of statistical uncertainty was discovered between the tumor and normal tissue populations and as such a modification to the CNI model was introduced to clearly identify that region. To address the issue of long scan times, a series of studies were conducted to adapt a scan acceleration technique, compressed sensing (CS), to work with MRSI and to quantify the effects of such a novel technique on the modulation transfer function (MTF), an important quantitative imaging metric. The studies included the development of the first phantom based method of measuring the MTF for MRSI data, a study of the correlation between the k-space sampling patterns used for compressed sensing and the resulting MTFs, and the introduction of a technique circumventing some of side-effects of compressed sensing by exploiting the conjugate symmetry property of k-space. The work in this thesis provides two essential steps towards wide clinical implementation of MRSI-based tumor delineation. The proposed modifications to the CNI method coupled with the application of CS to MRSI address the two main obstacles outlined. However, there continues to be room for improvement and questions that need to be answered by future research.

  3. 0-7-21 hypofractionated palliative radiotherapy: an effective treatment for advanced head and neck cancers

    PubMed Central

    Doerwald-Munoz, L; Zhang, H; Kim, D-H; Sagar, S; Wright, J R; Hodson, D I

    2015-01-01

    Objective: We report our experience in providing palliative radiotherapy (RT) to patients with head and neck cancers (HNCs). Our hypofractionated regimen, “0-7-21”, treats patients with 24 Gy in three fractions. Methods: Patients, disease and response data were retrieved for candidates of 0-7-21 from 2005 to 2012. Primary end points included symptom and tumour size responses to RT based on response evaluation criteria in solid tumours (RECIST) guidelines. Secondary end points included progression-free survival (PFS) within the irradiated field, overall survival (OS) and symptomatic PFS (SPFS), calculated using Kaplan–Meier method and adverse events. Cox proportional hazards regression and logistic regression were used to investigate for prognostic factors. Results: A total of 110 patients were included. Among the patients, 40% and 31% had complete response for symptoms and tumour size, respectively; 42% and 50% had partial response for symptoms and tumour size, respectively; and 15% had stability of symptoms and tumour size. Median 6-month OS was 51%, and PFS within the irradiated field was 39%. Planning target volume was predictive of OS (p < 0.001), PFS (p < 0.001) and SPFS (p < 0.005), while higher TNM stage was associated with poorer tumour response (p = 0.02). Conclusion: 0-7-21 is an effective and well-tolerated palliative RT regimen for patients with HNC. There was excellent symptom and local control with acceptable toxicity profile in these patients. Advances in knowledge: This is the first study to describe the outcomes of 0-7-21 in treating advanced HNCs. The positive results suggest that 0-7-21 provides excellent palliation with minimal toxicity, with significantly less on-treatment time than current published palliative RT regimen. PMID:25694259

  4. A Multiplan Treatment-Planning Framework: A Paradigm Shift for Intensity-Modulated Radiotherapy

    SciTech Connect

    Meyer, Robert R.; Zhang, Hao H.; Goadrich, Laura; Nazareth, Daryl P.; Shi Leyuan; D'Souza, Warren D. . E-mail: wdsou001@umaryland.edu

    2007-07-15

    Purpose: To describe a multiplan intensity-modulated radiotherapy (IMRT) planning framework, and to describe a decision support system (DSS) for ranking multiple plans and modeling the planning surface. Methods and Materials: One hundred twenty-five plans were generated sequentially for a head-and-neck case and a pelvic case by varying the dose-volume constraints on each of the organs at risk (OARs). A DSS was used to rank plans according to dose-volume histogram (DVH) values, as well as equivalent uniform dose (EUD) values. Two methods for ranking treatment plans were evaluated: composite criteria and pre-emptive selection. The planning surface determined by the results was modeled using quadratic functions. Results: The DSS provided an easy-to-use interface for the comparison of multiple plan features. Plan ranking resulted in the identification of one to three 'optimal' plans. The planning surface models had good predictive capability with respect to both DVH values and EUD values and generally, errors of <6%. Models generated by minimizing the maximum relative error had significantly lower relative errors than models obtained by minimizing the sum of squared errors. Using the quadratic model, plan properties for one OAR were determined as a function of the other OAR constraint settings. The modeled plan surface can then be used to understand the interdependence of competing planning objectives. Conclusion: The DSS can be used to aid the planner in the selection of the most desirable plan. The collection of quadratic models constructed from the plan data to predict DVH and EUD values generally showed excellent agreement with the actual plan values.

  5. Pulmonary Changes After Radiotherapy for Conservative Treatment of Breast Cancer: A Prospective Study

    SciTech Connect

    Krengli, Marco Sacco, Mariano; Loi, Gianfranco; Masini, Laura; Ferrante, Daniela; Gambaro, Giuseppina; Ronco, Marco; Magnani, Corrado; Carriero, Alessandro

    2008-04-01

    Purpose: Radiotherapy (RT) after conservative surgery for breast cancer involves part of the pulmonary parenchyma with a potential detrimental effect of reducing the normal functional reserve. Such an effect deserves to be studied in depth, considering the given long life expectancy of these women. We prospectively analyzed high-resolution computed tomography (HRCT) and pulmonary function tests (PFTs) with correlation with dosimetric data from RT. Methods and Materials: Lung HRCT and PFTs were performed in 41 women who had undergone conservative surgery for breast cancer before and 3 and 9 months after postoperative RT. The PFTs included forced vital capacity, forced expiratory volume in 1 s, total lung capacity, maximal expiratory flow at 50% and 25% of vital capacity, and the diffusion capacity of carbon monoxide. HRCT was matched with the RT treatment plan images to analyze the dosimetric correlation. Results: At 3 months after RT, the lung alterations were classified at HRCT as follows: 46.3% were Grade 1, 24.4% Grade 2, and 7.3% Grade 3, and at 9 months, 58.5% were Grade 1, 19.5% Grade 2, and 0% Grade 3. The PFTs showed a significant decrease at 3 months, with only partial recovery at 9 months. Chemotherapy, but not hormonal therapy, was associated with PFT changes. The grade of fibrosis increased with increasing lung volume treated to a dose {>=}25 Gy. Conclusion: Lung changes, mainly related to damage to the alveolar-capillary barrier and smallest airway ramifications, were observed at 3 months, with only partial recovery at 9 months after RT. Minimizing the lung volume receiving {>=}25 Gy could reduce pulmonary toxicity.

  6. [Patient-Reported Treatment Satisfaction with Stereotactic Radiotherapy in Neovascular Age-Related Macular Degeneration].

    PubMed

    Kurz, Maximilian; Rudolf, Martin; Holzhey, Annekatrin; Neubauer, Aljoscha S; Grisanti, Salvatore; Ranjbar, Mahdy

    2017-08-24

    Background Stereotactic radiotherapy (SRT) in conjunction with the common intravitreal injections (IVI) is a new adjuvant approach in neovascular age-related macular degeneration (AMD) patients. The aim of our study was to investigate factors influencing patient satisfaction one year after SRT. Methods A questionnaire was administered to 35 AMD patients who had consecutively undergone SRT using the IRay(®)-device at the Department of Ophthalmology, University of Lübeck. In addition to descriptive statistics, responses were evaluated by correlation analysis. Moreover, subgroup analyses were performed, using a classification of IVI responders (annual injection rate after SRT ≤ 3), visual acuity (VA) responders (VA improvement ≥ 0.2 logMAR) and double responders (annual injection rate after SRT ≤ 3 as well as VA improvement ≥ 0.2 logMAR). Results The response rate was 86%. With respect to their treatment expectations, twice as many patients hoped to receive less injections instead of a better vision. Those hoping for less injections were significantly more satisfied with their clinical outcome. In addition, IVI-responders were significantly more satisfied than IVI-non-responders, while VA-responders were not, compared to VA-non-responders. Conclusions Patient satisfaction seems to depend on patients' comprehension of how SRT affects their disease and what kinds of expectations were set. It is of utmost importance to provide the patients with adequate and comprehensible education and to define realistic goals prior to SRT. Georg Thieme Verlag KG Stuttgart · New York.

  7. Adjunctive radiotherapy with strontium-90 in the treatment of conjunctival squamous cell carcinoma

    SciTech Connect

    Kearsley, J.H.; Fitchew, R.S.; Taylor, R.G.

    1988-03-01

    Squamous cell carcinoma of the ocular conjunctiva is a relatively rare malignancy which is attended by a high rate of local recurrence following simple surgical excision. To date, the management of conjunctival squamous cell cancer has been controversial. From 1950 to 1985, 146 consecutive patients with superficial conjunctival squamous cell cancer were treated at the Queensland Radium Institute. All patients were treated by simple surgical excision of the visible conjunctival lesion followed by adjunctive radiotherapy. Of 140 patients with histologically confirmed squamous cell cancer, 123 were treated with a strontium-90 source, 10 with a radon ring, and 7 with superficial X ray therapy. Standard policy since 1960 has been to deliver an incident dose of 30 Gy in a single fraction within the first 48 post-operative hours to the surgical bed using a strontium-90 source on a stand-off eye applicator. This report will largely focus on the 123 patients who were treated with a strontium-90 source, of whom 107 received 30 Gy, 14 received 40 Gy (pre 1960) and one patient each received 20 and 25 Gy incident dose. Of 131 evaluable patients, there were only 3 who developed local recurrence. All 3 local recurrences developed in elderly men who had presented with extensive superficial primary tumors. Two of the three recurrences occurred in the two patients who were treated with doses less than 30 Gy. Both early and late radiation-induced complications following ablative surgery and treatment with strontium-90 were very uncommon. Three patients developed unsightly conjunctival telangiectasia, 2 patients developed a persistent scleral ulcer and 2 patients developed clinically significant cataracts.

  8. Combined treatment of anaplastic thyroid carcinoma with surgery, chemotherapy, and hyperfractionated accelerated external radiotherapy

    SciTech Connect

    De Crevoisier, Renaud . E-mail: rdecrevo@mdanderson.org; Baudin, Eric; Bachelot, Anne; Leboulleux, Sophie; Travagli, Jean-Paul; Caillou, Bernard; Schlumberger, Martin

    2004-11-15

    Purpose: To analyze a prospective protocol combining surgery, chemotherapy (CT), and hyperfractionated accelerated radiotherapy (RT) in anaplastic thyroid carcinoma. Methods and materials: Thirty anaplastic thyroid carcinoma patients (mean age, 59 years) were treated during 1990-2000. Tumor extended beyond the capsule gland in 26 patients, with tracheal extension in 8. Lymph node metastases were present in 18 patients and lung metastases in 6. Surgery was performed before RT-CT in 20 patients and afterwards in 4. Two cycles of doxorubicin (60 mg/m{sup 2}) and cisplatin (120 mg/m{sup 2}) were delivered before RT and four cycles after RT. RT consisted of two daily fractions of 1.25 Gy, 5 days per week to a total dose of 40 Gy to the cervical lymph node areas and the superior mediastinum. Results: Acute toxicity (World Health Organization criteria) was Grade 3 or 4 pharyngoesophagitis in 10 patients; Grade 4 neutropenia in 21, with infection in 13; and Grade 3 or 4 anemia and thrombopenia in 8 and 4, respectively. At the end of the treatment, a complete local response was observed in 19 patients. With a median follow-up of 45 months (range, 12-78 months), 7 patients were alive in complete remission, of whom 6 had initially received a complete tumor resection. Overall survival rate at 3 years was 27% (95% confidence interval 10-44%) and median survival 10 months. In multivariate analysis, tracheal extension and macroscopic complete tumor resection were significant factors in overall survival. Death was related to local progression in 5% of patients, to distant metastases in 68%, and to both in 27%. Conclusions: Main toxicity was hematologic. High long-term survival was obtained when RT-CT was given after complete surgery. This protocol avoided local tumor progression, and death was mainly caused by distant metastases.

  9. Stereotactic body radiotherapy (sbrt) in lung oligometastatic patients: role of local treatments

    PubMed Central

    2014-01-01

    Background Data in the literature suggest the existence of oligometastatic disease, a state in which metastases are limited in number and site. Different kinds of local therapies have been used for the treatment of limited metastases and in the recent years reports on the use of Stereotactic Ablative radiotherapy (SABR) are emerging and the early results on local control are promising. Patients and methods From October 2010 to February 2012, 76 consecutive patients for 118 lung lesions were treated. SABR was performed in case of controlled primary tumor, long-term of progression disease, exclusion of surgery, and number of metastatic sites ≤ 5. Different kinds of primary tumors were treated, the most common were lung and colon-rectal cancer. The total dose prescribed varied according to tumor site and maximum diameter. Dose prescription was 48 Gy in 4 fractions for peripheral lesions, 60 Gy in 8 fractions for central lesions and 60 Gy in 3 fractions for peripheral lesions with diameter ≤ 2 cm. Results Dosimetric planning objectives were met for the cohort of patients with in particular V98% = 98.1 ± 3.4% for the CTV and mean lung dose of 3.7 ± 3.8 Gy. Radiological response was obtained in the vast majority of patients. The local control at 1, 2 and 3 years was 95%, 89% and 89% respectively. No major pulmonary toxicity, chest pain or rib fracture occurred. The median follow up was 20 months (range 6–45 months). Overall Survival (OS) at 1, 2 and 3 years was 84.1%, 73% and 73% respectively. Conclusions SABR is feasible with limited morbidity and promising results in terms of local contro, survival and toxicity. PMID:24694067

  10. Stereotactic body radiotherapy (sbrt) in lung oligometastatic patients: role of local treatments.

    PubMed

    Navarria, Pierina; Ascolese, Anna Maria; Tomatis, Stefano; Cozzi, Luca; De Rose, Fiorenza; Mancosu, Pietro; Alongi, Filippo; Clerici, Elena; Lobefalo, Francesca; Tozzi, Angelo; Reggiori, Giacomo; Fogliata, Antonella; Scorsetti, Marta

    2014-04-02

    Data in the literature suggest the existence of oligometastatic disease, a state in which metastases are limited in number and site. Different kinds of local therapies have been used for the treatment of limited metastases and in the recent years reports on the use of Stereotactic Ablative radiotherapy (SABR) are emerging and the early results on local control are promising. From October 2010 to February 2012, 76 consecutive patients for 118 lung lesions were treated. SABR was performed in case of controlled primary tumor, long-term of progression disease, exclusion of surgery, and number of metastatic sites ≤ 5. Different kinds of primary tumors were treated, the most common were lung and colon-rectal cancer. The total dose prescribed varied according to tumor site and maximum diameter. Dose prescription was 48 Gy in 4 fractions for peripheral lesions, 60 Gy in 8 fractions for central lesions and 60 Gy in 3 fractions for peripheral lesions with diameter ≤ 2 cm. Dosimetric planning objectives were met for the cohort of patients with in particular V98% = 98.1 ± 3.4% for the CTV and mean lung dose of 3.7 ± 3.8 Gy. Radiological response was obtained in the vast majority of patients. The local control at 1, 2 and 3 years was 95%, 89% and 89% respectively. No major pulmonary toxicity, chest pain or rib fracture occurred. The median follow up was 20 months (range 6-45 months). Overall Survival (OS) at 1, 2 and 3 years was 84.1%, 73% and 73% respectively. SABR is feasible with limited morbidity and promising results in terms of local control, survival and toxicity.

  11. A prospective longitudinal study of voice characteristics and health-related quality of life outcomes following laryngeal cancer treatment with radiotherapy.

    PubMed

    Karlsson, Therese; Bergström, Liza; Ward, Elizabeth; Finizia, Caterina

    2016-06-01

    Background To investigate potential changes in perceptual, acoustic and patient-reported outcomes over 12 months for laryngeal cancer patients treated with radiotherapy. Material and methods A total of 40 patients with Tis-T3 laryngeal cancer treated with curative intent by radiotherapy were included in this prospective longitudinal descriptive study. Patients were followed pre-radiotherapy, one month, six months and 12 months post-radiotherapy, where voice recordings and patient-reported outcome instruments (European Organization for Research and Treatment of Cancer Quality-of-Life Questionnaire Core30, Head and Neck35, Swedish Self-Evaluation of Communication Experiences after Laryngeal Cancer) were completed at each appointment. Perceptual analysis, using the Grade-Roughness-Breathiness-Asthenia-Strain scale and vocal fry parameters, and acoustic measures including harmonics-to-noise ratio (HNR), jitter, shimmer and mean spoken fundamental frequency (MSFF) were produced from voice recordings. Results All patients presented with dysphonic voices pre-radiotherapy, where 95% demonstrated some degree of vocal roughness. This variable improved significantly immediately post-radiotherapy, however, then deteriorated again between six and 12 months. Vocal fry also increased significantly at 12 months. Acoustic measures were abnormal pre- and post-treatment with no significant change noted except for MSFF, which lowered significantly by 12 months. Health-related quality of life (HRQL) deteriorated post-radiotherapy but returned to pretreatment levels by 12 months. Conclusion By 12 months, most perceptual, acoustic, patient-reported voice and HRQL outcomes for laryngeal cancer patients treated by radiotherapy had showed no significant improvements compared to pretreatment function. Further studies are required to investigate potential benefits of voice rehabilitation following radiotherapy.

  12. Radioactive EGFR Antibody Cetuximab in Multimodal Cancer Treatment: Stability and Synergistic Effects With Radiotherapy

    SciTech Connect

    Rades, Dirk; Wolff, Christian; Nadrowitz, Roger; Breunig, Christian; Schild, Steven E.; Baehre, Manfred; Meller, Birgit

    2009-11-15

    Purpose: Systemic therapies when added to whole brain radiotherapy have failed to improve the survival of patients with multiple brain metastases. The epidermal growth factor receptor antibody cetuximab is an attractive option, if it is able to cross the blood-brain barrier. This might be proven with molecular imaging if the radiolabeled antibody is stable long enough to be effective. This study investigated the stability of radiolabeled cetuximab (Erbitux) ({sup 131}I-Erbi) and potential synergistic effects with radiotherapy in vitro. Methods and Materials: Two cell lines were investigated, A431 with numerous epidermal growth factor receptors, and JIMT without epidermal growth factor receptors. We labeled 0.4 mg cetuximab with 50 MBq of [{sup 131}I] iodide. Stability was determined for 72 h. The cell cultures were incubated with {sup 131}I-Erbi or cold cetuximab for 72 h. Uptake and cell proliferation were measured every 24 h after no radiotherapy or irradiation with 2, 4, or 10 Gy. Results: The radiolabeling yield of {sup 131}I-Erbi was always >80%. The radiochemical purity was still 93.6% after 72 h. A431 cells showed a {sup 131}I-Erbi uptake about 100-fold greater than the JIMT controls. After 48 h, the A431 cultures showed significantly decreased proliferation. At 72 h after irradiation, {sup 131}I-Erbi resulted in more pronounced inhibition of cell proliferation than the cold antibody in all radiation dose groups. Conclusion: {sup 131}I-Erbi was stable for <=72 h. Radiotherapy led to increased tumor cell uptake of {sup 131}I-Erbi. Radiotherapy and {sup 131}I-Erbi synergistically inhibited tumor cell proliferation. These results provide the prerequisite data for a planned in vivo study of whole brain radiotherapy plus cetuximab for brain metastases.

  13. New insights for pelvic radiation disease treatment: Multipotent stromal cell is a promise mainstay treatment for the restoration of abdominopelvic severe chronic damages induced by radiotherapy

    PubMed Central

    Chapel, Alain; Francois, Sabine; Douay, Luc; Benderitter, Marc; Voswinkel, Jan

    2013-01-01

    Radiotherapy may induce irreversible damage on healthy tissues surrounding the tumor. It has been reported that the majority of patients receiving pelvic radiation therapy show early or late tissue reactions of graded severity as radiotherapy affects not only the targeted tumor cells but also the surrounding healthy tissues. The late adverse effects of pelvic radiotherapy concern 5% to 10% of them, which could be life threatening. However, a clear medical consensus concerning the clinical management of such healthy tissue sequelae does not exist. Although no pharmacologic interventions have yet been proven to efficiently mitigate radiotherapy severe side effects, few preclinical researches show the potential of combined and sequential pharmacological treatments to prevent the onset of tissue damage. Our group has demonstrated in preclinical animal models that systemic mesenchymal stromal cell (MSC) injection is a promising approach for the medical management of gastrointestinal disorder after irradiation. We have shown that MSCs migrate to damaged tissues and restore gut functions after irradiation. We carefully studied side effects of stem cell injection for further application in patients. We have shown that clinical status of four patients suffering from severe pelvic side effects resulting from an over-dosage was improved following MSC injection in a compationnal situation. PMID:24179599

  14. Radiotherapy induced xerostomia: mechanisms, diagnostics, prevention and treatment--evidence based up to 2013.

    PubMed

    Kałużny, Jarosław; Wierzbicka, Małgorzata; Nogala, Hanna; Milecki, Piotr; Kopeć, Tomasz

    2014-01-01

    Definition and prevalence of xerostomia were shortly presented. Radiosensitivity of the salivary glands, mechanism, diagnostics, and possible prediction methods of the intensity of xerostomia in the pre-radiotherapy period are widely discussed. Prevention of xerostomia: salivary gland sparing radiotherapy, cytoprotective agents, preservation by stimulation with cholinergic muscarinic agonists, surgical transfer of submandibular glands according to ASCO Management Guidelines and Quality of Life Recommendations were cited. Oral Care Study Group (2010) therapeutic approaches for relieving xerostomia are referred. Current therapies, restricted to symptom relief such as oral hygiene with fluoride agents, antimicrobials to prevent dental caries, saliva substitutes to relieve symptoms, and sialogenic agents to stimulate saliva were also discussed.

  15. Treatment of childhood Hodgkin's disease with COPP or COPP-ABV (hybrid) without radiotherapy in Nicaragua.

    PubMed

    Baez, F; Ocampo, E; Conter, V; Flores, A; Gutierrez, T; Malta, A; Pacheco, C; Palacios, R; Biondi, A; Riva, L; Sala, A; Silvestri, D; Cavalli, F; Sessa, C; Casanova, M; Masera, G

    1997-03-01

    Childhood Hodgkin's disease (HD) in low-income countries has been reported to have distinct presenting features, including a high prevalence of the mixed cellularity subtype, which also seems to be associated with poorer prognosis. Further investigations are needed to evaluate these issues. Another controversial aspect of childhood HD is the use of radiotherapy (RT) in its treatment and the growing concern about its serious adverse side effects. In this paper, data on the diagnosis and outcome of children treated without RT in a low-income country (Nicaragua) are reported. Forty-eight consecutive children aged 0-15 years, diagnosed at 'La Mascota' Hospital of Managua (Nicaragua) from January 1990 to October 1995. entered this study. Follow-up was updated in May 1996. Clinical and histopathological staging was performed according to Ann Arbor and Rye criteria, respectively. Treatment consisted of COPP (six cycles) for stages I or IIA, or COPP-ABV hybrid): eight cycles for stages IIB or III, and ID cycles for stage IV. Total cumulative doses of adriamycin and bleomycin in this protocol are, respectively, 200 and 80 mg:sqm for stages II B or III and 250 and 100 mg/sqm for stage IV. The median age of the 48 patients at diagnosis was seven years, and the mean age was 7.9 years (range 3-15 years). Clinical stages were IA in 5, IIA in 9, IIB in 6, IIIA in 5, IIIB in 14, and IVB in 9. Histopathologically, 25 cases presented with mixed cellularity, 15 with nodular sclerosis, 5 with lymphocytic predominance and 3 with lymphocytic depletion. Four patients did not proceed with treatment and were lost to follow-up. Two patients (stages IIIB and IVB), who never achieved complete remission (CR) during treatment, presented progressive disease at the end of the scheduled chemotherapy. The remaining 42 patients were in complete remission at the end of chemotherapy. Following discontinuation of therapy, one patient (stage IA) was lost to follow-up and two patients with stage IIIB

  16. Japanese structure survey of high-precision radiotherapy in 2012 based on institutional questionnaire about the patterns of care.

    PubMed

    Tomita, Natsuo; Kodaira, Takeshi; Teshima, Teruki; Ogawa, Kazuhiko; Kumazaki, Yu; Yamauchi, Chikako; Toita, Takafumi; Uno, Takashi; Sumi, Minako; Onishi, Hiroshi; Kenjo, Masahiro; Nakamura, Katsumasa

    2014-06-01

    The purpose of this study was to clarify operational situations, treatment planning and processes, quality assurance and quality control with relevance to stereotactic radiotherapy, intensity-modulated radiotherapy and image-guided radiotherapy in Japan. We adopted 109 items as the quality indicators of high-precision radiotherapy to prepare a questionnaire. In April 2012, we started to publicly open the questionnaire on the website, requesting every institution with radiotherapy machines for response. The response ratio was 62.1% (490 out of 789 institutions responded). Two or more radiotherapy technologists per linear accelerator managed linear accelerator operation in ∼90% of the responded institutions while medical physicists/radiotherapy quality managers were engaged in the operation in only 64.9% of the institutions. Radiotherapy certified nurses also worked in only 18.4% of the institutions. The ratios of the institutions equipped for stereotactic radiotherapy of lung tumor, intensity-modulated radiotherapy and image-guided radiotherapy were 43.3, 32.6 and 46.8%, respectively. In intensity-modulated radiotherapy planning, radiation oncologists were usually responsible for delineation while medical physicists/radiotherapy quality managers or radiotherapy technologists set up beam in 33.3% of the institutions. The median time required for quality assurance of intensity-modulated radiotherapy at any site of brain, head and neck and prostate was 4 h. Intensity-modulated radiotherapy quality assurance activity had to be started after clinical hours in >60% of the institutions. This study clarified one major issue in the current high-precision radiotherapy in Japan. A manpower shortage should be corrected for high-precision radiotherapy, especially in the area relevant to quality assurance/quality control. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. A new active method for the measurement of slow-neutron fluence in modern radiotherapy treatment rooms

    NASA Astrophysics Data System (ADS)

    Gómez, F.; Iglesias, A.; Sánchez Doblado, F.

    2010-02-01

    This work focuses on neutron monitoring at clinical linac facilities during high-energy modality radiotherapy treatments. Active in-room measurement of neutron fluence is a complex problem due to the pulsed nature of the fluence and the presence of high photon background, and only passive methods have been considered reliable until now. In this paper we present a new active method to perform real-time measurement of neutron production around a medical linac. The device readout is being investigated as an estimate of patient neutron dose exposure on each radiotherapy session. The new instrument was developed based on neutron interaction effects in microelectronic memory devices, in particular using neutron-sensitive SRAM devices. This paper is devoted to the description of the instrument and measurement techniques, presenting the results obtained together with their comparison and discussion. Measurements were performed in several standard clinical linac facilities, showing high reliability, being insensitive to the photon fluence and EM pulse present inside the radiotherapy room, and having detector readout statistical relative uncertainties of about 2% on measurement of neutron fluence produced by 1000 monitor units irradiation runs.

  18. Evaluating changes in tumor volume using magnetic resonance imaging during the course of radiotherapy treatment of high-grade gliomas: Implications for conformal dose-escalation studies

    SciTech Connect

    Tsien, Christina . E-mail: ctsien@umich.edu; Gomez-Hassan, Diana; Haken, Randall K. ten; Tatro, Daniel C.; Junck, L.; Chenevert, T.L.; Lawrence, T.

    2005-06-01

    Objective: To determine whether changes in tumor volume occur during the course of conformal 3D radiotherapy of high-grade gliomas by use of magnetic resonance imaging (MRI) during treatment and whether these changes had an impact on tumor coverage. Methods and Materials: Between December 2000 and January 2004, 21 patients with WHO Grades 3 to 4 supratentorial malignant gliomas treated with 3D conformal radiotherapy (median dose, 70 Gy) were enrolled in a prospective clinical study. All patients underwent T1-weighted contrast-enhancing and T2-weighted and fluid-attenuated inversion recovery (FLAIR) imaging at approximately 1 to 2 weeks before radiotherapy, during radiotherapy (Weeks 1 and 3), and at routine intervals thereafter. All MRI scans were coregistered to the treatment-planning CT. Gross tumor volume (GTV Pre-Rx) was defined from a postoperative T1-weighted contrast-enhancing MRI performed 1 to 2 weeks before start of radiotherapy. A second GTV (GTV Week 3) was defined by use of an MRI performed during Week 3 of radiotherapy. A uniform 0.5 cm expansion of the respective GTV, PTV (Pre-Rx), and PTV (Week 3) was applied to the final boost plan. Dose-volume histograms (DVH) were used to analyze any potential adverse changes in tumor coverage based on Week 3 MRI. Results: All MRI scans were reviewed independently by a neuroradiologist (DGH). Two patients were noted to have multifocal disease at presentation and were excluded from analysis. In 19 cases, changes in the GTV based on MRI at Week 3 during radiotherapy were as follows: 2 cases had an objective decrease in GTV ({>=}50%); 12 cases revealed a slight decrease in the rim enhancement or changes in cystic appearance of the GTV; 2 cases showed no change in GTV; and 3 cases demonstrated an increase in tumor volume. Both cases with objective decreases in GTV during treatment were Grade 3 tumors. No cases of tumor progression were noted in Grade 3 tumors during treatment. In comparison, three of 12 Grade 4

  19. Case report of a near medical event in stereotactic radiotherapy due to improper units of measure from a treatment planning system.

    PubMed

    Gladstone, D J; Li, S; Jarvis, L A; Hartford, A C

    2011-07-01

    The authors hereby notify the Radiation Oncology community of a potentially lethal error due to improper implementation of linear units of measure in a treatment planning system. The authors report an incident in which a patient was nearly mistreated during a stereotactic radiotherapy procedure due to inappropriate reporting of stereotactic coordinates by the radiation therapy treatment planning system in units of centimeter rather than in millimeter. The authors suggest a method to detect such errors during treatment planning so they are caught and corrected prior to the patient positioning for treatment on the treatment machine. Using pretreatment imaging, the authors found that stereotactic coordinates are reported with improper linear units by a treatment planning system. The authors have implemented a redundant, independent method of stereotactic coordinate calculation. Implementation of a double check of stereotactic coordinates via redundant, independent calculation is simple and accurate. Use of this technique will avoid any future error in stereotactic treatment coordinates due to improper linear units, transcription, or other similar errors. The authors recommend an independent double check of stereotactic treatment coordinates during the treatment planning process in order to avoid potential mistreatment of patients.

  20. Case report of a near medical event in stereotactic radiotherapy due to improper units of measure from a treatment planning system

    SciTech Connect

    Gladstone, D. J.; Li, S.; Jarvis, L. A.; Hartford, A. C.

    2011-07-15

    Purpose: The authors hereby notify the Radiation Oncology community of a potentially lethal error due to improper implementation of linear units of measure in a treatment planning system. The authors report an incident in which a patient was nearly mistreated during a stereotactic radiotherapy procedure due to inappropriate reporting of stereotactic coordinates by the radiation therapy treatment planning system in units of centimeter rather than in millimeter. The authors suggest a method to detect such errors during treatment planning so they are caught and corrected prior to the patient positioning for treatment on the treatment machine. Methods: Using pretreatment imaging, the authors found that stereotactic coordinates are reported with improper linear units by a treatment planning system. The authors have implemented a redundant, independent method of stereotactic coordinate calculation. Results: Implementation of a double check of stereotactic coordinates via redundant, independent calculation is simple and accurate. Use of this technique will avoid any future error in stereotactic treatment coordinates due to improper linear units, transcription, or other similar errors. Conclusions: The authors recommend an independent double check of stereotactic treatment coordinates during the treatment planning process in order to avoid potential mistreatment of patients.

  1. The Adjoint Method for The Optimization of Brachytherapy and Radiotherapy Patient Treatment Planning Procedures Using Monte Carlo Calculations

    SciTech Connect

    D.L. Henderson; S. Yoo; M. Kowalok; T.R. Mackie; B.R. Thomadsen

    2001-10-30

    The goal of this project is to investigate the use of the adjoint method, commonly used in the reactor physics community, for the optimization of radiation therapy patient treatment plans. Two different types of radiation therapy are being examined, interstitial brachytherapy and radiotherapy. In brachytherapy radioactive sources are surgically implanted within the diseased organ such as the prostate to treat the cancerous tissue. With radiotherapy, the x-ray source is usually located at a distance of about 1-metere from the patient and focused on the treatment area. For brachytherapy the optimization phase of the treatment plan consists of determining the optimal placement of the radioactive sources, which delivers the prescribed dose to the disease tissue while simultaneously sparing (reducing) the dose to sensitive tissue and organs. For external beam radiation therapy the optimization phase of the treatment plan consists of determining the optimal direction and intensity of beam, which provides complete coverage of the tumor region with the prescribed dose while simultaneously avoiding sensitive tissue areas. For both therapy methods, the optimal treatment plan is one in which the diseased tissue has been treated with the prescribed dose and dose to the sensitive tissue and organs has been kept to a minimum.

  2. X-ray volumetric imaging in image-guided radiotherapy: The new standard in on-treatment imaging

    SciTech Connect

    McBain, Catherine A.; Henry, Ann M. . E-mail: catherine.mcbain@christie-tr.nwest.nhs.uk; Sykes, Jonathan; Amer, Ali; Marchant, Tom; Moore, Christopher M.; Davies, Julie; Stratford, Julia; McCarthy, Claire; Porritt, Bridget; Williams, Peter; Khoo, Vincent S.; Price, Pat

    2006-02-01

    Purpose: X-ray volumetric imaging (XVI) for the first time allows for the on-treatment acquisition of three-dimensional (3D) kV cone beam computed tomography (CT) images. Clinical imaging using the Synergy System (Elekta, Crawley, UK) commenced in July 2003. This study evaluated image quality and dose delivered and assessed clinical utility for treatment verification at a range of anatomic sites. Methods and Materials: Single XVIs were acquired from 30 patients undergoing radiotherapy for tumors at 10 different anatomic sites. Patients were imaged in their setup position. Radiation doses received were measured using TLDs on the skin surface. The utility of XVI in verifying target volume coverage was qualitatively assessed by experienced clinicians. Results: X-ray volumetric imaging acquisition was completed in the treatment position at all anatomic sites. At sites where a full gantry rotation was not possible, XVIs were reconstructed from projection images acquired from partial rotations. Soft-tissue definition of organ boundaries allowed direct assessment of 3D target volume coverage at all sites. Individual image quality depended on both imaging parameters and patient characteristics. Radiation dose ranged from 0.003 Gy in the head to 0.03 Gy in the pelvis. Conclusions: On-treatment XVI provided 3D verification images with soft-tissue definition at all anatomic sites at acceptably low radiation doses. This technology sets a new standard in treatment verification and will facilitate novel adaptive radiotherapy techniques.

  3. Photon energy-modulated radiotherapy: Monte Carlo simulation and treatment planning study

    SciTech Connect

    Park, Jong Min; Kim, Jung-in; Heon Choi, Chang; Chie, Eui Kyu; Kim, Il Han; Ye, Sung-Joon

    2012-03-15

    Purpose: To demonstrate the feasibility of photon energy-modulated radiotherapy during beam-on time. Methods: A cylindrical device made of aluminum was conceptually proposed as an energy modulator. The frame of the device was connected with 20 tubes through which mercury could be injected or drained to adjust the thickness of mercury along the beam axis. In Monte Carlo (MC) simulations, a flattening filter of 6 or 10 MV linac was replaced with the device. The thickness of mercury inside the device varied from 0 to 40 mm at the field sizes of 5 x 5 cm{sup 2} (FS5), 10 x 10 cm{sup 2} (FS10), and 20 x 20 cm{sup 2} (FS20). At least 5 billion histories were followed for each simulation to create phase space files at 100 cm source to surface distance (SSD). In-water beam data were acquired by additional MC simulations using the above phase space files. A treatment planning system (TPS) was commissioned to generate a virtual machine using the MC-generated beam data. Intensity modulated radiation therapy (IMRT) plans for six clinical cases were generated using conventional 6 MV, 6 MV flattening filter free, and energy-modulated photon beams of the virtual machine. Results: As increasing the thickness of mercury, Percentage depth doses (PDD) of modulated 6 and 10 MV after the depth of dose maximum were continuously increased. The amount of PDD increase at the depth of 10 and 20 cm for modulated 6 MV was 4.8% and 5.2% at FS5, 3.9% and 5.0% at FS10 and 3.2%-4.9% at FS20 as increasing the thickness of mercury from 0 to 20 mm. The same for modulated 10 MV was 4.5% and 5.0% at FS5, 3.8% and 4.7% at FS10 and 4.1% and 4.8% at FS20 as increasing the thickness of mercury from 0 to 25 mm. The outputs of modulated 6 MV with 20 mm mercury and of modulated 10 MV with 25 mm mercury were reduced into 30%, and 56% of conventional linac, respectively. The energy-modulated IMRT plans had less integral doses than 6 MV IMRT or 6 MV flattening filter free plans for tumors located in the

  4. Photon energy-modulated radiotherapy: Monte Carlo simulation and treatment planning study.

    PubMed

    Park, Jong Min; Kim, Jung-in; Heon Choi, Chang; Chie, Eui Kyu; Kim, Il Han; Ye, Sung-Joon

    2012-03-01

    To demonstrate the feasibility of photon energy-modulated radiotherapy during beam-on time. A cylindrical device made of aluminum was conceptually proposed as an energy modulator. The frame of the device was connected with 20 tubes through which mercury could be injected or drained to adjust the thickness of mercury along the beam axis. In Monte Carlo (MC) simulations, a flattening filter of 6 or 10 MV linac was replaced with the device. The thickness of mercury inside the device varied from 0 to 40 mm at the field sizes of 5 × 5 cm(2) (FS5), 10 × 10 cm(2) (FS10), and 20 × 20 cm(2) (FS20). At least 5 billion histories were followed for each simulation to create phase space files at 100 cm source to surface distance (SSD). In-water beam data were acquired by additional MC simulations using the above phase space files. A treatment planning system (TPS) was commissioned to generate a virtual machine using the MC-generated beam data. Intensity modulated radiation therapy (IMRT) plans for six clinical cases were generated using conventional 6 MV, 6 MV flattening filter free, and energy-modulated photon beams of the virtual machine. As increasing the thickness of mercury, Percentage depth doses (PDD) of modulated 6 and 10 MV after the depth of dose maximum were continuously increased. The amount of PDD increase at the depth of 10 and 20 cm for modulated 6 MV was 4.8% and 5.2% at FS5, 3.9% and 5.0% at FS10 and 3.2%-4.9% at FS20 as increasing the thickness of mercury from 0 to 20 mm. The same for modulated 10 MV was 4.5% and 5.0% at FS5, 3.8% and 4.7% at FS10 and 4.1% and 4.8% at FS20 as increasing the thickness of mercury from 0 to 25 mm. The outputs of modulated 6 MV with 20 mm mercury and of modulated 10 MV with 25 mm mercury were reduced into 30%, and 56% of conventional linac, respectively. The energy-modulated IMRT plans had less integral doses than 6 MV IMRT or 6 MV flattening filter free plans for tumors located in the periphery while maintaining the

  5. Fractionated stereotactic radiotherapy for the treatment of large arteriovenous malformations with or without previous partial embolization.

    PubMed

    Veznedaroglu, Erol; Andrews, David W; Benitez, Ronald P; Downes, M Beverly; Werner-Wasik, Maria; Rosenstock, Jeffrey; Curran, Walter J; Rosenwasser, Robert H

    2008-02-01

    Despite the success of stereotactic radiosurgery, large inoperable arteriovenous malformations (AVMs) of 14 cm3 or more have remained largely refractory to stereotactic radiosurgery, with much lower obliteration rates. We review treatment of large AVMs either previously untreated or partially obliterated by embolization with fractionated stereotactic radiotherapy (FSR) regimens using a dedicated linear accelerator (LINAC). Before treatment, all patients were discussed at a multidisciplinary radiosurgery board and found to be suitable for FSR. All patients were evaluated for pre-embolization. Those who had feeding pedicles amenable to glue embolization were treated. LINAC technique involved acquisition of a stereotactic angiogram in a relocatable frame that was also used for head localization during treatment. The FSR technique involved the use of six 7-Gy fractions delivered on alternate days over a 2-week period, and this was subsequently dropped to 5-Gy fractions after late complications in one of seven patients treated with 7-Gy fractions. Treatments were based exclusively on digitized biplanar stereotactic angiographic data. We used a Varian 600SR LINAC (Varian Medical Systems, Inc., Palo Alto, CA) and XKnife treatment planning software (Radionics, Inc., Burlington, MA). In most cases, one isocenter was used, and conformality was established by non-coplanar arc beam shaping and differential beam weighting. Thirty patients with large AVMs were treated between January 1995 and August 1998. Seven patients were treated with 42-Gy/7-Gy fractions, with one patient lost to follow-up and the remaining six with previous partial embolization. Twenty-three patients were treated with 30-Gy/5-Gy fractions, with two patients lost to follow-up and three who died as a result of unrelated causes. Of 18 evaluable patients, 8 had previous partial embolization. MeanAVM volumes at FSR treatment were 23.8 and 14.5 cm3, respectively, for the 42-Gy/7-Gy fraction and 30-Gy/5-Gy

  6. Fractionated stereotactic radiotherapy for the treatment of large arteriovenous malformations with or without previous partial embolization.

    PubMed

    Veznedaroglu, Erol; Andrews, David W; Benitez, Ronald P; Downes, M Beverly; Werner-Wasik, Maria; Rosenstock, Jeffrey; Curran, Walter J; Rosenwasser, Robert H

    2004-09-01

    Despite the success of stereotactic radiosurgery, large inoperable arteriovenous malformations (AVMs) of 14 cm(3) or more have remained largely refractory to stereotactic radiosurgery, with much lower obliteration rates. We review treatment of large AVMs either previously untreated or partially obliterated by embolization with fractionated stereotactic radiotherapy (FSR) regimens using a dedicated linear accelerator (LINAC). Before treatment, all patients were discussed at a multidisciplinary radiosurgery board and found to be suitable for FSR. All patients were evaluated for pre-embolization. Those who had feeding pedicles amenable to glue embolization were treated. LINAC technique involved acquisition of a stereotactic angiogram in a relocatable frame that was also used for head localization during treatment. The FSR technique involved the use of six 7-Gy fractions delivered on alternate days over a 2-week period, and this was subsequently dropped to 5-Gy fractions after late complications in one of seven patients treated with 7-Gy fractions. Treatments were based exclusively on digitized biplanar stereotactic angiographic data. We used a Varian 600SR LINAC (Varian Medical Systems, Inc., Palo Alto, CA) and XKnife treatment planning software (Radionics, Inc., Burlington, MA). In most cases, one isocenter was used, and conformality was established by non-coplanar arc beam shaping and differential beam weighting. Thirty patients with large AVMs were treated between January 1995 and August 1998. Seven patients were treated with 42-Gy/7-Gy fractions, with one patient lost to follow-up and the remaining six with previous partial embolization. Twenty-three patients were treated with 30-Gy/5-Gy fractions, with two patients lost to follow-up and three who died as a result of unrelated causes. Of 18 evaluable patients, 8 had previous partial embolization. Mean AVM volumes at FSR treatment were 23.8 and 14.5 cm(3), respectively, for the 42-Gy/7-Gy fraction and 30-Gy/5-Gy

  7. Energy Dependence of Measured CT Numbers on Substituted Materials Used for CT Number Calibration of Radiotherapy Treatment Planning Systems

    PubMed Central

    Mahmoudi, Reza; Jabbari, Nasrollah; aghdasi, Mehdi; Khalkhali, Hamid Reza

    2016-01-01

    Introduction For accurate dose calculations, it is necessary to provide a correct relationship between the CT numbers and electron density in radiotherapy treatment planning systems (TPSs). The purpose of this study was to investigate the energy dependence of measured CT numbers on substituted materials used for CT number calibration of radiotherapy TPSs and the resulting errors in the treatment planning calculation doses. Materials and Methods In this study, we designed a cylindrical water phantom with different materials used as tissue equivalent materials for the simulation of tissues and obtaining the related CT numbers. For evaluating the effect of CT number variations of substituted materials due to energy changing of scanner (kVp) on the dose calculation of TPS, the slices of the scanned phantom at three kVp's were imported into the desired TPSs (MIRS and CorePLAN). Dose calculations were performed on two TPSs. Results The mean absolute percentage differences between the CT numbers of CT scanner and two treatment planning systems for all the samples were 3.22%±2.57% for CorePLAN and 2.88%±2.11% for MIRS. It was also found that the maximum absolute percentage difference between all of the calculated doses from each photon beam of linac (6 and 15 MV) at three kVp's was less than 1.2%. Discussion The present study revealed that, for the materials with effective low atomic number, the mean CT number increased with increasing energy, which was opposite for the materials with an effective high atomic number. We concluded that the tissue substitute materials had a different behavior in the energy ranges from 80 to 130 kVp. So, it is necessary to consider the energy dependence of the substitute materials used for the measurement or calibration of CT number for radiotherapy treatment planning systems. PMID:27391672

  8. Sci—Thur PM: Planning and Delivery — 02: Treatment planning workflow for very high-energy electron beam radiotherapy

    SciTech Connect

    Bazalova, Magdalena; Qu, Bradley; Palma, Bianey; Maxim, Peter; Loo, Billy; Hårdemark, Bjorn; Hynning, Elin

    2014-08-15

    Purpose: To develop treatment planning workflow for rapid radiotherapy delivered with very-high energy electron (VHEE) scanning beam. Methods: VHEE radiotherapy treatment planning was performed by linking Monte Carlo (MC) dose calculations with inverse optimization in a research version of RayStation. In order to study a number of treatment parameters, a Matlab graphical user interface (GUI) for calculation of VHEE beamlet dose was developed. Through the GUI, EGSnrc MC simulations were run for a number of beam energies, number of beams, beamlet spot and grid sizes, and machine bore sizes. VHEE plans for a pediatric patient with a 4.3 cm{sup 3} brain target optimized with spot-scanning algorithm in RayStation were compared to the clinically delivered 6 MV VMAT plan. Results and Discussion: VHEE beam energy had the largest effect on the quality of dose distributions. For the same target dose, the mean doses to critical organs decreased by 10–15% when planned with 100 MeV compared to 60 MeV. VHEE plans calculated with 36 beams outperformed plans calculated with 13 and 17 beams. While beamlet spacing and bore size had a small effect on VHEE dose distributions, 0.1-3mm beamlet sizes resulted in identical dose distributions. Critical organ doses were by up to 70% lower in the best VHEE plan compared to the clinical 6 MV VMAT plan. Conclusions: We have developed a GUI for MC beamlet generation for treatment planning of VHEE radiotherapy. We have demonstrated that pediatric VHEE plans resulted in significant critical organ dose sparing compared to the clinical VMAT plan.

  9. Prognostic factors and treatment outcome after radiotherapy in cervical cancer patients with isolated para-aortic lymph node metastases

    PubMed Central

    Jang, Hyunsoo; Cho, Oyeon; Heo, Jae Sung; Ryu, Hee-Sug; Chang, Suk-Joon

    2013-01-01

    Objective The purpose of the present study was to evaluate treatment outcomes and prognostic factors in cervical cancer patients with isolated para-aortic lymph node (PALN) metastases. We especially tried to evaluate PALN factors such as size, site and number. Methods From August 1994 to December 2009, 40 cervical cancer patients with isolated PALN node metastases at initial diagnosis were selected for analysis. Patients underwent both extended field external beam and intracavitary brachytherapy. Fourteen patients received 5-fluorouracil and cisplatin (FP) and 16 patients received weekly concurrent cisplatin. Information of PALN, such as size, site, and number, was founded before PALN radiotherapy. Results The median follow-up time after primary treatment was 28.5 months (range, 2 to 213 months). The 3-year overall and progression-free survival rate after primary treatment was 44.3% and 31.3%, respectively. In multivariate analysis including tumor stage, performance status, and chemotherapy, FP regimen concurrent chemoradiotherapy was more effective than radiotherapy alone (p=0.030). The 3-year progression-free survival rate was 41.9% and 11.1% in patients with PALN numbers of ≤1 and ≥2, respectively (p=0.008). The 3-year progression-free survival rate was 42.1% and 19.2% in patients with PALN size of <1.5 cm and ≥1.5 cm, respectively (p=0.031). Conclusion The radiologic features of PALN, such as number or size, can be used to determine prognosis in PALN metastatic cervical cancer patients. Furthermore, FP regimen concurrent chemoradiotherapy was associated with better patient survival than radiotherapy alone. However, more studies are required to confirm possible different treatment outcomes between FP and weekly cisplatin regimens. PMID:23875072

  10. Evaluating proton stereotactic body radiotherapy to reduce chest wall dose in the treatment of lung cancer

    SciTech Connect

    Welsh, James; Amini, Arya; Ciura, Katherine; Nguyen, Ngoc; Palmer, Matt; Soh, Hendrick; Allen, Pamela K.; Paolini, Michael; Liao, Zhongxing; Bluett, Jaques; Mohan, Radhe; Gomez, Daniel; Cox, James D.; Komaki, Ritsuko; Chang, Joe Y.

    2013-01-01

    Stereotactic body radiotherapy (SBRT) can produce excellent local control of several types of solid tumor; however, toxicity to nearby critical structures is a concern. We found previously that in SBRT for lung cancer, the chest wall (CW) volume receiving 20, 30, or 40 Gy (V{sub 20}, V{sub 30}, or V{sub 40}) was linked with the development of neuropathy. Here we sought to determine whether the dosimetric advantages of protons could produce lower CW doses than traditional photon-based SBRT. We searched an institutional database to identify patients treated with photon SBRT for lung cancer with tumors within < 2.5 cm of the CW. We found 260 cases; of these, chronic grade ≥ 2 CW pain was identified in 23 patients. We then selected 10 representative patients from this group and generated proton SBRT treatment plans, using the identical dose of 50 Gy in 4 fractions, and assessed potential differences in CW dose between the 2 plans. The proton SBRT plans reduced the CW doses at all dose levels measured. The median CW V{sub 20} was 364.0 cm{sup 3} and 160.0 cm{sup 3} (p < 0.0001), V{sub 30} was 144.6 cm{sup 3}vs 77.0 cm{sup 3} (p = 0.0012), V{sub 35} was 93.9 cm{sup 3}vs 57.9 cm{sup 3} (p = 0.005), V{sub 40} was 66.5 cm{sup 3}vs 45.4 cm{sup 3} (p = 0.0112), and mean lung dose was 5.9 Gy vs 3.8 Gy (p = 0.0001) for photons and protons, respectively. Coverage of the planning target volume (PTV) was comparable between the 2 sets of plans (96.4% for photons and 97% for protons). From a dosimetric standpoint, proton SBRT can achieve the same coverage of the PTV while significantly reducing the dose to the CW and lung relative to photon SBRT and therefore may be beneficial for the treatment of lesions closer to critical structures.

  11. SU-E-T-43: Analytical Model for Photon Peripheral Dose in Radiotherapy Treatments

    SciTech Connect

    Nieto, B Sanchez; El far, R; Romero-Exposito, M; Lagares, J; Mateo, JC; Terron, JA; Irazola, L; Sanchez-Doblado, F

    2014-06-01

    Purpose: The higher survival rate of radiotherapy patients entails a growing concern on second cancers associated to peripheral doses. Currently, dosimetry of out-of field doses is still under development. Our group has developed a methodology to estimate neutron equivalent dose in organs (1,2). We aimed to propose a model to estimate out-of-field photon doses in isocentric treatments from basic clinical data. Methods: The proposed function models the dose as the sum of leakage and scatter terms. The latter is modeled as a virtual source at the collimator, which suffers from attenuation in air and tissue, corrected by the inverse-square-law. The model was parameterized using experimental measurements with TLD700 chips placed inside an anthropomorphic phantom (6–18MV) irradiated with conformal and modulated techniques in Elekta, Siemens and Varian linacs. This model provides photon dose at a point as a function of clinical parameters as prescription dose/UM, PTV volume, distance to the field edge, height of the MLC leaves and distance from the the MLC to the isocenter. Model was tested against independent measurements (TLD100) for a VMAT treatment on a Elekta. Dose to organs is modeled from dose to points along the head-to-feet axis of the organ of a “standard man” escalated by patient height. Results: Our semi-empirical model depends on 3 given parameters (leakage parameter can be individualized). A novelty of our model, over other models (e.g., PERIDOSE), arises from its applicability to any technique (independently of the number of MU needed to deliver a dose). Differences between predictions and measurements were < 0.005mSv/UM. Conclusion: We have proposed a unique model which successfully account for photon peripheral organ dose. This model can be applied in the day-to-day clinic as it only needs a few basic parameters which are readily accessible.1. Radiother. Oncol. 107:234–243, 2013. 2. Phys. Med. Biol. 57:6167–6191, 2012.

  12. Radiotherapy in the treatment of primary central nervous system lymphoma (PCNSL).

    PubMed

    Nelson, D F

    1999-07-01

    The use of radiotherapy alone to treat primary central nervous system lymphoma (PCNSL) does not produce the high local control and survival rates that it does in limited extranodal non-Hodgkin's lymphoma outside the central nervous system (CNS). Even with doses of whole brain radiation therapy (WBRT) to 40+20 Gy boost, the Radiation Therapy Oncology Group (RTOG) reported a local control rate of 39%. Seventy-nine percent of recurrences were in the 60 Gy region. The median survival was 11.6 months. This response to local radiotherapy is quite different from the response of non-CNS Diffuse Large Cell Lymphoma where doses of 30-40 and >40 Gy have a 75-90% local control rate. Neither systemic lymphoma nor PCNSL have a classic radiotherapy dose response. For PCNSL there appears to be a threshold dose that ranges in the literature between 30 and > 50 Gy with a median of 40 Gy. Therefore, when radiotherapy is combined with chemotherapy that crosses the BBB, WBRT and/or boost doses may be able to be decreased, especially in patients achieving a complete response. Promising data from the Centre Leon Berard suggest that this is possible. When such chemotherapy was combined with intrathecal chemotherapy and 20 Gy WBRT, they obtained a 56% actuarial 5 year survival rate. Confirmation of single institution reports of favorable results such as these are needed. Cooperative group and intergroup trials are needed to define optimal therapy.

  13. Impact of 18F-fluoro-2-deoxyglucose positron emission tomography on treatment strategy and radiotherapy planning for stage I-II Hodgkin disease: a prospective multicenter study.

    PubMed

    Pommier, Pascal; Dussart, Sophie; Girinsky, Théodore; Chabaud, Sylvie; Lagrange, Jean Leon; Nguyen, Tan Dat; Beckendorff, Véronique; D'Hombres, Anne; Artignan, Xavier; Bondiau, Pierre Yves; Carrie, Christian; Giammarile, Francesco

    2011-03-01

    To quantify the impact of preradiotherapy 18F-fluoro-2-deoxyglucose positron-emission tomography (FDG-PET) on treatment strategy and radiotherapy planning for patients with Stage I/II Hodgkin disease included in a large prospective multicenter study. Conventional computed tomography and FDG-PET were performed just before the planned radiotherapy. The radiotherapy plan was first elaborated under blinded conditions for FDG-PET data. Then, the medical staff was asked to confirm or not confirm the treatment strategy and, if appropriate, to modify the radiotherapy plan based on additional information from FDG-PET. Between January 2004 and January 2006, 137 patients were included (124 were available for analysis) in 11 centers (108 adults, 16 children). All but 1 patient had received chemotherapy before inclusion. Prechemotherapy work-up included FDG-PET for 61 patients, and data were available for elaboration of the first radiotherapy plan. Based on preradiotherapy FDG-PET data, the radiotherapy was cancelled in 6 patients (4.8%), and treatment plan modifications occurred in 16 patients (12.9%): total dose (11 patients), CTV volume (5 patients), number of beam incidences (6 patients), and number of CTV (6 patients). The concordance between the treatment strategies with or without preradiotherapy FDG-PET was 82.3%. Concordance results were not significantly different when prechemotherapy PET-CT information was available. Preradiotherapy FDG-PET for treatment planning in Hodgkin lymphoma may lead to significant modification of the treatment strategy and the radiotherapy planning in patients with Stage I or II Hodgkin disease, even in those who have undergone FDG-PET as part of the prechemotherapy work-up. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Impact of 18F-Fluoro-2-Deoxyglucose Positron Emission Tomography on Treatment Strategy and Radiotherapy Planning for Stage I-II Hodgkin Disease: A Prospective Multicenter Study

    SciTech Connect

    Pommier, Pascal; Dussart, Sophie; Girinsky, Theodore; Chabaud, Sylvie; Lagrange, Jean Leon; Nguyen, Tan Dat; Beckendorff, Veronique; D'Hombres, Anne; Artignan, Xavier; Bondiau, Pierre Yves; Carrie, Christian; Giammarile, Francesco

    2011-03-01

    Purpose: To quantify the impact of preradiotherapy 18F-fluoro-2-deoxyglucose positron-emission tomography (FDG-PET) on treatment strategy and radiotherapy planning for patients with Stage I/II Hodgkin disease included in a large prospective multicenter study. Patients and Methods: Conventional computed tomography and FDG-PET were performed just before the planned radiotherapy. The radiotherapy plan was first elaborated under blinded conditions for FDG-PET data. Then, the medical staff was asked to confirm or not confirm the treatment strategy and, if appropriate, to modify the radiotherapy plan based on additional information from FDG-PET. Results: Between January 2004 and January 2006, 137 patients were included (124 were available for analysis) in 11 centers (108 adults, 16 children). All but 1 patient had received chemotherapy before inclusion. Prechemotherapy work-up included FDG-PET for 61 patients, and data were available for elaboration of the first radiotherapy plan. Based on preradiotherapy FDG-PET data, the radiotherapy was cancelled in 6 patients (4.8%), and treatment plan modifications occurred in 16 patients (12.9%): total dose (11 patients), CTV volume (5 patients), number of beam incidences (6 patients), and number of CTV (6 patients). The concordance between the treatment strategies with or without preradiotherapy FDG-PET was 82.3%. Concordance results were not significantly different when prechemotherapy PET-CT information was available. Conclusion: Preradiotherapy FDG-PET for treatment planning in Hodgkin lymphoma may lead to significant modification of the treatment strategy and the radiotherapy planning in patients with Stage I or II Hodgkin disease, even in those who have undergone FDG-PET as part of the prechemotherapy work-up.

  15. [Hodgkin's lymphoma and radiotherapy].

    PubMed

    Datsenko, P V; Panshin, G A

    2015-01-01

    After a median observation time of 4,5 years, 440 patients with Hodgkin's lymphoma stage I-IV to the Ann Arbor classification were treated with radiotherapy (2200 lymph areas) and ABVD (n=204) or BEACOPP (n=117) or CEA/ABVD (lomustine, etoposide, adriamycine, bleomycine, vinblastine and dacarbacine; n=119) regimens in 1995-2012. Correct allocation of groups with "CR or PR ≥80%" and "PR: 0-79%", after first-line chemotherapy, is extremely important for following RT planning. Adaptation of patients with Hodgkin's lymphoma can take place only after successful treatment, the probability of relapse and fear of repeated courses strongly interfere with this process, especially in the first years after its closure. Duration of remission period, especially in young people, is no less important than the criteria for overall survival. It is impossible to build recommendations for treatment for Hodgkin's lymphoma, based only on long-term survival rates. Importance of radiotherapy in reducing the number of relapses is undeniable, so the idea that the development of the role of chemotherapy in the treatment of the ray method Hodgkin's lymphoma gradually becomes secondary is in serious doubt. Our findings suggest the importance of both maintaining a high disease-free survival and reducing long-term complications in designing treatments of Hodgkin's lymphoma.

  16. Phase I/II Trial Evaluating Carbon Ion Radiotherapy for Salvaging Treatment of Locally Recurrent Nasopharyngeal Carcinoma

    PubMed Central

    Kong, Lin; Hu, Jiyi; Guan, Xiyin; Gao, Jing; Lu, Rong; Lu, Jiade J.

    2016-01-01

    Background: Radiation therapy is the mainstay strategy for the treatment of nasopharyngeal cancer (NPC). Intensity-modulated X-ray therapy (IMXT) alone is the current standard for stage I and II NPC. For stage III and IV A/B diseases, concurrent chemotherapy should be provided in addition to IMXT. However, optimal treatment for locally recurrent NPC after previous definitive dose of radiotherapy is lacking. Various techniques including brachytherapy, IMXT, stereotactic radiosurgery or radiotherapy (SRS or SBRT) have been used in the management of locally recurrent NPC. Due to the inherent limitation of these techniques, i.e., limited range of irradiation or over-irradiation to surrounding normal tissues, moderate efficacy has been observed at the cost of severe toxicities. Carbon ion radiotherapy (CIRT) offers potential physical and biological advantages over photon and proton radiotherapy. Due to the inverted dose profile of particle beams and their greater energy deposition within the Bragg peak, precise dose delivery to the target volume(s) without exposing the surrounding organs at risk to extra doses is possible. In addition, CIRT provides an increased relative biological effectiveness (RBE) as compared to photon and proton radiotherapy. Such advantages may translate to improved outcomes after irradiation in terms of disease control in radio-resistant and previously treated, recurrent malignancies. It is therefore reasonable to postulate that recurrent NPC after high-dose radiotherapy could be more resistant to re-irradiation using photons. Reports on the treatment of radio-resistant malignancies in the head and neck region such as melanoma, sarcoma, and adenoid cystic carcinoma (ACC) have demonstrated superior local control rates from CIRT as compared to photon irradiation. Thus patients with recurrent NPC are likely to benefit from the enhanced biological effectiveness of carbon ions. As effective retreatment strategy is lacking for locally recurrent NPC

  17. Phase I/II Trial Evaluating Carbon Ion Radiotherapy for Salvaging Treatment of Locally Recurrent Nasopharyngeal Carcinoma.

    PubMed

    Kong, Lin; Hu, Jiyi; Guan, Xiyin; Gao, Jing; Lu, Rong; Lu, Jiade J

    2016-01-01

    Radiation therapy is the mainstay strategy for the treatment of nasopharyngeal cancer (NPC). Intensity-modulated X-ray therapy (IMXT) alone is the current standard for stage I and II NPC. For stage III and IV A/B diseases, concurrent chemotherapy should be provided in addition to IMXT. However, optimal treatment for locally recurrent NPC after previous definitive dose of radiotherapy is lacking. Various techniques including brachytherapy, IMXT, stereotactic radiosurgery or radiotherapy (SRS or SBRT) have been used in the management of locally recurrent NPC. Due to the inherent limitation of these techniques, i.e., limited range of irradiation or over-irradiation to surrounding normal tissues, moderate efficacy has been observed at the cost of severe toxicities. Carbon ion radiotherapy (CIRT) offers potential physical and biological advantages over photon and proton radiotherapy. Due to the inverted dose profile of particle beams and their greater energy deposition within the Bragg peak, precise dose delivery to the target volume(s) without exposing the surrounding organs at risk to extra doses is possible. In addition, CIRT provides an increased relative biological effectiveness (RBE) as compared to photon and proton radiotherapy. Such advantages may translate to improved outcomes after irradiation in terms of disease control in radio-resistant and previously treated, recurrent malignancies. It is therefore reasonable to postulate that recurrent NPC after high-dose radiotherapy could be more resistant to re-irradiation using photons. Reports on the treatment of radio-resistant malignancies in the head and neck region such as melanoma, sarcoma, and adenoid cystic carcinoma (ACC) have demonstrated superior local control rates from CIRT as compared to photon irradiation. Thus patients with recurrent NPC are likely to benefit from the enhanced biological effectiveness of carbon ions. As effective retreatment strategy is lacking for locally recurrent NPC, carbon ion

  18. Validation of in-house treatment planning system software for cobalt-60 teletherapy unit at two radiotherapy installations

    NASA Astrophysics Data System (ADS)

    Mu'minah, I. A. S.; Toresano, L. O. H. Z.; Wibowo, W. E.; Sugiyantari; Pawiro, S. A.

    2016-03-01

    DSSuperDose v.1.0 is an in-house treatment planning system (TPS) developed by Medical Physics and Biophysics Laboratory (LFMB) Universitas Indonesia as a treatment planning software for Cobalt-60 teletherapy unit. The main objective of this study was the validation of in-house TPS calculation as an essential part in quality assurance (QA) of radiotherapy. Validation of an in-house TPS was performed with two Cobalt-60 teletherapy units by comparison between in-house TPS and ISIS TPS and by measurements of absorbed dose. Mean dose deviations between in-house TPS and measurement were (1.97 ± 2.42)% for open field, (1.32 ± 1.30)% for tray field, and (2.91 ± 2.36)% for wedge field treatments. In-house TPS provide optimal planning for open and tray beam conditions with depth fewer than 10 cm (≤ 10 cm) and field sizes up to 20×20 cm2, while for wedge beam conditions with field sizes fewer than the physical size of the wedge. Comparison of in-house TPS and ISIS TPS demonstrated a good match of 96%. From the results, it is concluded that DSSuperDose v.1.0 is adequately accurate for treatment planning of radiotherapy.

  19. The novel microtubule targeting agent BAL101553 in combination with radiotherapy in treatment-refractory tumor models.

    PubMed

    Sharma, Ashish; Broggini-Tenzer, Angela; Vuong, Van; Messikommer, Alessandra; Nytko, Katarzyna J; Guckenberger, Matthias; Bachmann, Felix; Lane, Heidi A; Pruschy, Martin

    2017-09-01

    Resistance to microtubule targeting agents (MTA) represents a major drawback in successful cancer therapy with MTAs. Here we investigated the combined treatment modality of the novel MTA BAL101553 in combination with radiotherapy in paclitaxel and epothilone-resistant tumor models. Multiple regimens of BAL101553, or its active moiety BAL27862 for in vitro experiments, were probed in combination with radiotherapy in P-glycoprotein-overexpressing, human colon adenocarcinoma cells (SW480) and in tubulin-mutated human NSCLC cells (A549EpoB40) and tumors thereof. BAL27862 reduced the proliferative activity of SW480 and A549EpoB40 tumor cells with similar potency as in A549 wildtype cells. Combined treatment of BAL27862 with ionizing radiation in vitro resulted in an additive reduction of clonogenicity. Moreover, treatment of paclitaxel- and epothilone-resistant tumors with fractionated irradiation and different regimens of BAL101553 (a single i.v. bolus vs. oral daily) suppressed tumor growth and resulted in an extended additive tumor growth delay with strong reduction of tumor proliferation and mean tumor vessel density. BAL101553 is a promising alternative in taxane- and epothilone-refractory tumors as part of a combined treatment modality with ionizing radiation. Its potent antitumor effect is not only tumor cell-directed but also targets the tumor microenvironment. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Response to treatment and interval to surgery after preoperative short-course radiotherapy in rectal cancer.

    PubMed

    García-Cabezas, Sonia; Rodríguez-Liñán, Milagrosa; Otero-Romero, Ana M; Bueno-Serrano, Carmen M; Gómez-Barbadillo, José; Palacios-Eito, Amalia

    2016-10-01

    Preoperative short-course radiotherapy with immediate surgery improves local control in patients with rectal cancer. Tumor responses are smaller than those described with radiochemotherapy. Preliminary data associate this lower response to the short period until surgery. The aim of this study is to analyze the response to preoperative short-course radiotherapy and its correlation with the interval to surgery especially analyzing patients with mesorectal fascia involvement. A total of 155 patients with locally advanced rectal cancer treated with preoperative radiotherapy (5×5Gy) were retrospectively analyzed. Tumor response in terms of rates of complete pathological response, downstaging, tumor regression grading and status of the circumferential resection margin were quantified. The mean interval from radiotherapy to surgery was 23 days. The rate of complete pathological response was 2.2% and 28% experienced downstaging (stage decreased). No differences between these rates and interval to surgery were detected. Eighty-eight patients had magnetic resonance imaging for staging (in 31 patients the mesorectal fascia was involved).The mean time to surgery in patients with involvement of the fascia and R0 surgery was 27 days and 16 days if R1 (P=.016). The cutoff of 20 days reached the highest probability of achieving a free circumferential resection margin between patients with mesorectal fascia involvement, with no statistically significant differences: RR 3.036 95% CI=(0.691-13.328), P=.06. After preoperative short-course radiotherapy, an interval>20 days enhances the likelihood of achieving a free circumferential resection margin in patients with mesorectal fascia involvement. Copyright © 2016 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  1. Pilot study of estramustine added to radiosurgery and radiotherapy for treatment of high grade glioma.

    PubMed

    Landy, Howard; Markoe, Arnold; Potter, Priscilla; Lasalle, Garrett; Marini, Angela; Savaraj, Niramol; Reis, Isildinha; Heros, Deborah; Wangpaichitr, Medhi; Feun, Lynn

    2004-01-01

    Patients with high grade glioma generally have poor prognoses. Addition of radiosensitizing agents might improve the response to irradiation. The chemotherapeutic agent estramustine sensitizes experimental gliomas to radiation. Gliomas express estramustine binding proteins, and cytotoxic concentrations of estramustine metabolites are found in gliomas after oral administration. Twenty three patients, aged 25-78, with new or recurrent high grade glioma were treated with estramustine and radiosurgery and/or radiotherapy. Patients with recurrent tumors were treated with estramustine and Gamma Knife stereotactic radiosurgery; eligible tumors were limited to 4 cm maximal diameter. Patients with newly diagnosed tumors were treated with estramustine and fractionated radiotherapy, with radiosurgery also performed if the tumor was less than 4 cm maximal diameter. Estramustine (16 mg/kg per day orally) was started three days prior to radiosurgery, or, if only radiotherapy was performed, on the first day of radiotherapy. Estramustine was continued until the completion of radiosurgery and/or radiotherapy (72 Gy, 60 fractions, 1.2 Gy bid over 6 weeks). Of the 13 patients treated for newly diagnosed glioblastoma, median survival was 16 months with 38% 2-year survival. Of five patients treated for recurrent glioblastoma, survival was 3, 8, 9, 15, and 23 + months. Two patients with recurrent anaplastic astrocytoma survived for 24 and 48+ months. One patient with recurrent anaplastic mixed glioma survived 5+ months. Two patients with newly diagnosed anaplastic oligodendroglioma survived 20 and 42+ months. Four of the new glioblastoma patients developed deep vein thrombosis. The results of this pilot study indicate some benefit, and further investigation incorporating estramustine into clinical trials is suggested.

  2. The end-of-treatment telephone response and prognosis of post-radiotherapy nasopharyngeal carcinoma patients in southern China.

    PubMed

    Chen, Mu-Yao; Chen, Yu-Shan; Hu, Li-Jing; Lun, Xue-Ping; He, Dan-Dan; Chen, Pei-Fen; Hu, Lian-Ying

    2015-01-01

    Nasopharyngeal Carcinoma (NPC) patients' end-of-treatment survival status has drawn more attention in recent years. Telephone follow-up, as a most operative approach among all the clinical follow-ups, is an effective means to extend medical service to patients' home and is thus widely used in clinical practice. This study aimed to analyze the post-radiotherapy NPC patients' phone response rate and its factors, and to discuss the independent prognostic factors of NPC patients' radiotherapy. We prospectively designed a nurses-led telephone follow-up to include 2520 NPC patients who received simple radical radiotherapy between Jan. 2007 and Jun. 2012 at Sun Yat-sen University Cancer Center. The patients' response rate and its factors were calculated. Survival analysis was used to estimate the patients' survival and the influencing factors. The overall response rate was 90.5%; Patients with reserved contact type of mobile + landlinephone or landline phone had higher follow-up response rate than patients with mobile contact only; patients with 2 or more reserved contacts, and family cancer history had higher response rate than patients with only 1 number and those without family history. Patients' cumulative survival rate of 1, 3 and 5 years were 98.9%, 75.3%, 50.3%, respectively. T-staging, N-staging, higher clinical staging, with basicranial invasion were the influencing factors of the patients' poor prognosis. The telephone follow-up response was affected by reserved contact type, number of contacts and family medical history; T-staging, N-staging, higher clinical staging, with basicranial invasion were the influencing factors of the patients' poor prognosis. This study provides a scientific basis for increasing the NPC patients' end-of-treatment response and promoting the individualized clinical treatment.

  3. [Efficacy observation of accelerated hyperfractionation recourse radiotherapy plus concurrent capecitabine in the treatment of locoregional recurrent rectal cancer].

    PubMed

    Zhang, Jian-dong; Dai, Yong; Yu, Jin-ming; Shao, Zhen-yu

    2010-04-13

    To evaluate the efficacy of accelerated hyperfractionation (CAF) radiotherapy plus concurrent capecitabine in the treatment of locoregional recurrent rectal cancer. Between June 2004 and January 2008, 53 patients with locoregional recurrent rectal cancer were treated with CAF 1.2 Gy/f, 2 f/d plus concurrent capecitabine at an oral dosage of 825 mg/m2 bid on each day of radiotherapy period. The first daily dose was applied at 2 h pre-irradiation, d1-14 and d22-35. After a regimen of 36 Gy/30 f/3 w, the feasibility of surgical resection was then evaluated by CT. Patients unsuitable for surgical resection continued CAF. And the total dose was 52.8-57.6 Gy. The complete response rate was 9.8%, the partial response rate 45.1%, the effective rate 54.9%, the no-change rate 29.4%, the progression rate 15.7%, the surgical resection rate 23.5% and the R0, R1 resection rates 21.6% and 1.9% respectively. The Time to Progression was 10.5 months, 1-year survival rate was 84.3%, 2-year survival rate was 61.1%. Quality of life improved in treatment group. Toxic and adverse effects were gastrointestinal and hematological toxicities. There was no treatment-related mortality. The 3-dimensional conformal radiotherapy plus concurrent chemotherapy may be an effective and well-tolerated regimen in patients with postoperative locoregional recurrent or metastatic rectal cancer.

  4. Phase i study evaluating the treatment of patients with hepatocellular carcinoma (HCC) with carbon ion radiotherapy: the PROMETHEUS-01 trial.

    PubMed

    Combs, Stephanie E; Habermehl, Daniel; Ganten, Tom; Schmidt, Jan; Edler, Lutz; Burkholder, Iris; Jäkel, Oliver; Haberer, Thomas; Debus, Jürgen

    2011-02-12

    Treatment options for patients with advanced hepatocellular carcinoma (HCC) are often limited. In most cases, they are not amenable to local therapies including surgery or radiofrequency ablation. The multi-kinase inhibitor sorafenib has shown to increase overall survival in this patient group for about 3 months.Radiation therapy is a treatment alternative, however, high local doses are required for long-term local control. However, due to the relatively low radiation tolerance of liver normal tissue, even using stereotactic techniques, delivery of sufficient doses for successful local tumor control has not be achieved to date.Carbon ions offer physical and biological characteristics. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increased relative biological effectiveness (RBE), which can be calculated between 2 and 3 depending on the HCC cell line as well as the endpoint analyzed.Japanese Data on the evaluation of carbon ion radiation therapy showed promising results for patients with HCC. In the current Phase I-PROMETHEUS-01-Study, carbon ion radiotherapy will be evaluated for patients with advanced HCC. The study will be performed as a dose-escalation study evaluating the optimal carbon ion dose with respect to toxicity and tumor control.Primary endpoint is toxicity, secondary endpoint is progression-free survival and response. The Prometheus-01 trial ist the first trial evaluating carbon ion radiotherapy delivered by intensity-modulated rasterscanning for the treatment of HCC. Within this Phase I dose escalation study, the optimal dose of carbon ion radiotherapy will be determined. NCT 01167374.

  5. Phase i study evaluating the treatment of patients with hepatocellular carcinoma (HCC) with carbon ion radiotherapy: The PROMETHEUS-01 trial

    PubMed Central

    2011-01-01

    Background Treatment options for patients with advanced hepatocellular carcinoma (HCC) are often limited. In most cases, they are not amenable to local therapies including surgery or radiofrequency ablation. The multi-kinase inhibitor sorafenib has shown to increase overall survival in this patient group for about 3 months. Radiation therapy is a treatment alternative, however, high local doses are required for long-term local control. However, due to the relatively low radiation tolerance of liver normal tissue, even using stereotactic techniques, delivery of sufficient doses for successful local tumor control has not be achieved to date. Carbon ions offer physical and biological characteristics. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increased relative biological effectiveness (RBE), which can be calculated between 2 and 3 depending on the HCC cell line as well as the endpoint analyzed. Japanese Data on the evaluation of carbon ion radiation therapy showed promising results for patients with HCC. Methods/Design In the current Phase I-PROMETHEUS-01-Study, carbon ion radiotherapy will be evaluated for patients with advanced HCC. The study will be performed as a dose-escalation study evaluating the optimal carbon ion dose with respect to toxicity and tumor control. Primary endpoint is toxicity, secondary endpoint is progression-free survival and response. Discussion The Prometheus-01 trial ist the first trial evaluating carbon ion radiotherapy delivered by intensity-modulated rasterscanning for the treatment of HCC. Within this Phase I dose escalation study, the optimal dose of carbon ion radiotherapy will be determined. Trial registration NCT 01167374 PMID:21314962

  6. Efficacy of Traditional Chinese Medicine in Treatment and Prophylaxis of Radiation-Induced Oral Mucositis in Patients Receiving Radiotherapy: A Randomized Controlled Trial.

    PubMed

    Wang, Cong; Wang, Peiguo; Ouyang, Huaqiang; Wang, Jing; Sun, Lining; Li, Yanwei; Liu, Dongying; Jiang, Zhansheng; Wang, Bin; Pan, Zhanyu

    2017-09-01

    To estimate the efficacy of traditional Chinese medicine (Chining decoction, CHIN) for radiation-induced oral mucositis in patients with head and neck cancer. From May 2014 to December 2015, 70 consecutive patients were randomly assigned to receive CHIN (treatment group) or recombinant human epidermal growth factor (rhEGF) spray (control group) at a 1:1 ratio. CHIN was administered to treatment group from the first day of radiotherapy until the completion of radiotherapy. Simultaneously, the rhEGF spray was administered to control group on the oral mucosa of irradiated area. The clinical benefit was determined by gradation of mucositis (Common Terminology Criteria for Adverse Events v4.0), oral pain, and xerostomia (visual analysis scale) for each week during radiotherapy. Body mass index was evaluated before and after radiotherapy. Patients in the treatment group had prominent remission of oral pain and grade of mucositis on each observing point compared with those in control group ( P < .01). Xerostomia was decreased notably in treatment group compared with control group ( P < .01). Body mass index in the treatment group exhibited advantage over control group after radiotherapy, but there was no statistical significance (19.8 ± 3.26 vs 18.8 ± 2.5 kg/m(2), P = .153, >.05). CHIN presented an obvious advantage in preventing radiation-induced oral mucositis compared with rhEGF spray.

  7. Written information material and availability of sexual health care for men experiencing sexual dysfunction after prostate cancer treatment: An evaluation of Dutch urology and radiotherapy departments.

    PubMed

    Grondhuis Palacios, L A; Krouwel, E M; Duijn, M; den Oudsten, B L; den Ouden, M E M; Putter, H; Pelger, R C M; Elzevier, H W

    2017-03-01

    Objective was to investigate content of written information material and availability of sexual health care for men experiencing sexual dysfunction (SD) after prostate cancer treatment. A cross-sectional survey was conducted among Dutch urology and radiotherapy departments to evaluate information materials and availability of sexual health care. Out of 71 eligible departments, 34 urology and 15 radiotherapy departments participated in the survey (response rate 69.0%). Fifty-nine brochures corresponding to 31 urology and 11 radiotherapy departments were analysed. In 88.1% of collected information material, sexual health was mentioned. Regarding extensiveness, 20.4% of the brochures contained extensive information, 50.8% moderate amount of information and 28.8% contained little or no information. Urology departments provided pre-treatment nurse consultations more often than radiotherapy departments. Sexual counselling was more frequently provided by urology departments. Urology departments were more aware of adequate referral possibilities. Information material provided by Dutch urology and radiotherapy departments does not address treatment-related SD routinely. Sexual health care is not available everywhere for men experiencing SD. Applying a standard regarding content of sexual health in information material is recommended as well as improved awareness of referral possibilities and enhanced provision of pre-treatment nurse consultations for men experiencing SD after prostate cancer treatment.

  8. What is the impact of innovation on output in healthcare with a special focus on treatment innovations in radiotherapy? A literature review.

    PubMed

    Jacobs, Maria; Boersma, Liesbeth; Dekker, Andre; Swart, Rachelle; Lambin, Philippe; De Ruysscher, Dirk; Verhaegen, Frank; Stultiens, Joost; Ramaekers, Bram; Frits, van Merode

    2017-08-06

    To analyse how often innovations in healthcare are evaluated regarding output, especially in radiotherapy. Output was defined as either survival, toxicity, safety, service, efficiency or costeffectiveness. A systematic literature review was conducted, using three search strategies: 1) innovations in general healthcare; 2) radiotherapy-specific innovations, i.e. organisational innovations and general implementation of innovations; 3) innovations per tumour group/radiotherapy technique. Scientific levels were classified according to the system used in European Society for Medical Oncology (ESMO) guidelines. Finally, we calculated the percentage of implemented innovations in Dutch radiotherapy centres for which we found evidence regarding output in the literature review. Only 94/1072 unique articles matched the inclusion criteria. Significant results on patient outcome, service or safety were reported in 65% of papers, which rose to 76% if confined to radiotherapy reviews. A significant technological improvement was identified in 26%, cost-effectiveness in 10% and costs/efficiency in 36% of the papers. The scientific level of organisational innovations was lower than of clinical papers. Dutch radiotherapy treatment innovations were adequately evaluated on outcome data before implementation in clinical routine in a minimum of 64-92% of cases. Only few studies report on output when considering innovations in general, but radiotherapy reviews give a reasonably good insight into innovation output effects, with a higher level of evidence. In Dutch radiotherapy centres only small improvements are possible regarding evaluation of treatment innovations before implementation. Advances in Knowledge: This study is the first of its kind measuring how innovations are evaluated in scientific literature, before implementation in clinical practice.

  9. Integration of surgery with fractionated stereotactic radiotherapy for treatment of nonfunctioning pituitary macroadenomas

    SciTech Connect

    Paek, Sun Ha; Downes, M. Beverly; Bednarz, Greg; Keane, William M.; Werner-Wasik, Maria; Curran, Walter J.; Andrews, David W. . E-mail: david.andrews@jefferson.edu

    2005-03-01

    Objective: To evaluate the efficacy of fractionated stereotactic radiotherapy (FSRT) after surgery in the management of residual or recurrent nonfunctioning pituitary adenomas with respect to tumor control and the development of complications. Methods and materials: The clinical records of patients with nonfunctioning pituitary adenomas who underwent FSRT were retrospectively analyzed. For newly diagnosed tumors, transsphenoidal surgery was performed, and, if residual tumor was identified at 3 months, FSRT was performed. If significant tumor volume persisted, transcranial surgery was performed before FSRT. We originally initiated FSRT with 2-Gy fractions to 46 Gy. We escalated the dose to 50.4 Gy thereafter. As a final modification, we dropped the daily dose to 1.8-Gy fractions delivered within 6 weeks. High-dose conformality and homogeneity was achieved with arc beam shaping and differential beam weighting. The radiographic, endocrinologic, and visual outcomes after FSRT were evaluated. Results: The 68 patients included 36 males and 32 females with an age range of 15-81 years. The median follow-up was 30 months (range, 2-82 months), and the median tumor volume was 6.2 cm{sup 3}. Of the 68 patients, 20 were treated to 46 Gy and 48 to 50-52.2 Gy. Most were treated to 50.4 Gy. Eleven patients had recurrent tumors, 54 had residual tumors, and no surgery was performed in 3 patients before FSRT. We noted no radiation-induced acute or late toxicities, except for radiation-induced optic neuropathy in 2 patients. At latest follow-up, the tumor had decreased in size in 26 patients and remained stable in 41 of the 42 remaining patients. Of the 68 patients, 4 (6%) developed hypopituitarism at 6, 11, 12, and 17 months after FSRT. Reviewing available serial Humphrey visual fields, visual fields were objectively improved in 28 patients, and remained stable in 24 patients, and worsened in 2 patients. Conclusion: The findings of this analysis support the use of surgery followed by

  10. Alternate calibration method of radiochromic EBT3 film for quality assurance verification of clinical radiotherapy treatments

    NASA Astrophysics Data System (ADS)

    Park, Soah; Kang, Sei-Kwon; Cheong, Kwang-Ho; Hwang, Taejin; Yoon, Jai-Woong; Koo, Taeryool; Han, Tae Jin; Kim, Haeyoung; Lee, Me Yeon; Bae, Hoonsik; Kim, Kyoung Ju

    2016-07-01

    EBT3 film is utilized as a dosimetry quality assurance tool for the verification of clinical radiotherapy treatments. In this work, we suggest a percentage-depth-dose (PDD) calibration method that can calibrate several EBT3 film pieces together at different dose levels because photon beams provide different dose levels at different depths along the axis of the beam. We investigated the feasibility of the film PDD calibration method based on PDD data and compared the results those from the traditional film calibration method. Photon beams at 6 MV were delivered to EBT3 film pieces for both calibration methods. For the PDD-based calibration, the film pieces were placed on solid phantoms at the depth of maximum dose (dmax) and at depths of 3, 5, 8, 12, 17, and 22 cm, and a photon beam was delivered twice, at 100 cGy and 400 cGy, to extend the calibration dose range under the same conditions. Fourteen film pieces, to maintain their consistency, were irradiated at doses ranging from approximately 30 to 400 cGy for both film calibrations. The film pieces were located at the center position on the scan bed of an Epson 1680 flatbed scanner in the parallel direction. Intensity-modulated radiation therapy (IMRT) plans were created, and their dose distributions were delivered to the film. The dose distributions for the traditional method and those for the PDD-based calibration method were evaluated using a Gamma analysis. The PDD dose values using a CC13 ion chamber and those obtained by using a FC65-G Farmer chamber and measured at the depth of interest produced very similar results. With the objective test criterion of a 1% dosage agreement at 1 mm, the passing rates for the four cases of the three IMRT plans were essentially identical. The traditional and the PDD-based calibrations provided similar plan verification results. We also describe another alternative for calibrating EBT3 films, i.e., a PDD-based calibration method that provides an easy and time-saving approach

  11. High-resolution fluence verification for treatment plan specific QA in ion beam radiotherapy

    NASA Astrophysics Data System (ADS)

    Martišíková, Mária; Brons, Stephan; Hesse, Bernd M.; Jäkel, Oliver

    2013-03-01

    Ion beam radiotherapy exploits the finite range of ion beams and the increased dose deposition of ions toward the end of their range in material. This results in high dose conformation to the target region, which can be further increased using scanning ion beams. The standard method for patient-plan verification in ion beam therapy is ionization chamber dosimetry. The spatial resolution of this method is given by the distance between the chambers (typically 1 cm). However, steep dose gradients created by scanning ion beams call for more information and improved spatial resolution. Here we propose a clinically applicable method, supplementary to standard patient-plan verification. It is based on ion fluence measurements in the entrance region with high spatial resolution in the plane perpendicular to the beam, separately for each energy slice. In this paper the usability of the RID256 L amorphous silicon flat-panel detector for the measurements proposed is demonstrated for carbon ion beams. The detector provides sufficient spatial resolution for this kind of measurement (pixel pitch 0.8 mm). The experiments were performed at the Heidelberg Ion-Beam Therapy Center in Germany. This facility is equipped with a synchrotron capable of accelerating ions from protons up to oxygen to energies between 48 and 430 MeV u-1. Beam application is based on beam scanning technology. The measured signal corresponding to single energy slices was translated to ion fluence on a pixel-by-pixel basis, using calibration, which is dependent on energy and ion type. To quantify the agreement of the fluence distributions measured with those planned, a gamma-index criterion was used. In the patient field investigated excellent agreement was found between the two distributions. At least 95% of the slices contained more than 96% of points agreeing with our criteria. Due to the high spatial resolution, this method is especially valuable for measurements of strongly inhomogeneous fluence

  12. A new approach to quantify the mechanical and radiation isocentres of radiotherapy treatment machine gantries

    NASA Astrophysics Data System (ADS)

    Skworcow, Piotr; Mills, John A.; Haas, Olivier C. L.; Burnham, Keith J.

    2007-12-01

    In this paper a new method is proposed to quantify and reduce the radiation beam position uncertainty due to the radiotherapy treatment machine gantry deflection. A new tool has been designed and manufactured to provide the means to measure the alignment of the collimator axis and of the beam central axis in space, using the NDI Polaris optical tracking system and Gafchromic® films. The tool can be mounted onto the accessory tray of the linacs from different manufacturers. The approach has been demonstrated with measurements of the mechanical isocentre being performed on ten linacs from three major manufacturers at four clinical sites. Measurements of the radiation isocentre were performed on a single linac. The collimator axis trajectory is modelled using a vector-end effector in order to provide more information than standard mechanical assessment methods. The method uses a mathematical optimization technique to calculate the position of the mechanical isocentre and the 'size' of the collimator axes intersection locus. Deviations of the collimator axes from the isocentre are expressed in terms of systematic and random error. The effects of measurement uncertainties are evaluated both via simulations and experimentally. The use of optical tracking and optimization techniques combined with an operator-induced measurement error compensation algorithm leads to a faster measurement of the mechanical isocentre (20 min for 24 angles) and eliminates operator-induced uncertainties. The uncertainty of the measurement of the mechanical isocentre was between 40 µm and 70 µm in terms of standard deviation. For some of the linacs assessed, the mechanical isocentre obtained using a standard approach with an adjustable pointer was displaced by over 1 mm from that found with the proposed method. The radii of the collimator axes intersection locus found with the proposed method were between 0.4 mm and 0.72 mm for the linacs assessed. Film measurement revealed a misalignment of

  13. The feasibility of using a conventional flexible RF coil for an online MR-guided radiotherapy treatment

    NASA Astrophysics Data System (ADS)

    Hoogcarspel, Stan J.; Crijns, Sjoerd P. M.; Lagendijk, Jan J. W.; van Vulpen, Marco; Raaymakers, Bas W.

    2013-03-01

    The purpose of this paper is to evaluate the impact of a flexible radiofrequency coil on the treatment delivery of an online MR-guided radiotherapy treatment. For this study, we used a Synergy MR body coil (Philips, Best) in combination with the current MRL prototype of the UMC Utrecht. The compatibility of the coil is evaluated in two steps. First, we evaluated the dosimetric impact of the MR coil on both a simple and a complex irradiation strategy for treating spinal bone metastases. This tumor site will likely be chosen for the first in-man treatments with the UMC Utrecht MRL system. Second, we investigated the impact of the treatment beam on the MRI performance of the body coil. In case a single posterior-anterior rectangular field was applied, dose to the target volume was underestimated up to 2.2% as a result of beam attenuation in the MR coil. This underestimation however, decreased to 1% when a stereotactic treatment strategy was employed. The presence of the MR coil in or near the distal site of the treatment beam decreased the exit dose when a magnetic field was present. The MRI performance of the coil was unaffected as the result of the radiation. It is feasible to use the Synergy MR body coil for an online MR-guided radiotherapy treatment without any modification to the coil or attenuation correction methods in the planning stage. The effect of the MRI coil on the dose delivery is minimal and there is no effect of the treatment beam on the SNR of the acquired MRI data.

  14. [Current status of phase III study of combined treatment with radiotherapy and chemotherapy for head and neck cancer].

    PubMed

    Inoue, T; Inoue, T; Murayama, S

    1995-02-01

    Concerning the combined treatment with radiotherapy and chemotherapy for head and neck cancer, in general, there are many discrepancies between a single institutional pilot study and a multi-institutional prospective randomized study. Some of the differences depend on the insufficient number of patients entered into the study, since the annual incidence of head and neck cancer is relatively low, and the treatment result varies from site to site as well as the stage of the disease. Several types of bias, including patient selection and positive publications, and factors related to the design and analysis of clinical trials result in additional differences. To solve these problems, we organized the Quality Assurance Research Group in Japan, funded by the Ministry of Health and Welfare for several years. Based on much effort, it was emphasized the need for increased manpower and equipment in radiation oncology, for a quality assurance program of radiotherapy and the preparation of a standard treatment modality using decision tree and surrogate survey.

  15. Real-time respiration monitoring using the radiotherapy treatment beam and four-dimensional computed tomography (4DCT)--a conceptual study.

    PubMed

    Lu, Weiguo; Ruchala, Kenneth J; Chen, Ming-Li; Chen, Quan; Olivera, Gustavo H

    2006-09-21

    Real-time knowledge of intra-fraction motion, such as respiration, is essential for four-dimensional (4D) radiotherapy. Surrogate-based and internal-fiducial-based methods may suffer from one or many drawbacks such as false correlation, being invasive, delivering extra patient radiation, and requiring complicated hardware and software development and implementation. In this paper we develop a simple non-surrogate, non-invasive method to monitor respiratory motion during radiotherapy treatments in real time. This method directly utilizes the treatment beam and thus imposes no additional radiation to the patient. The method requires a pre-treatment 4DCT and a real-time detector system. The method combines off-line processes with on-line processes. The off-line processes include 4DCT imaging and pre-calculating detector signals at each phase of the 4DCT based on the planned fluence map and the detector response function. The on-line processes include measuring detector signal from the treatment beam, and correlating the measured detector signal with the pre-calculated signals. The respiration phase is determined as the position of peak correlation. We tested our method with extensive simulations based on a TomoTherapy machine and a 4DCT of a lung cancer patient. Three types of simulations were implemented to mimic the clinical situations. Each type of simulation used three different TomoTherapy delivery sinograms, each with 800 to 1000 projections, as input fluences. Three arbitrary breathing patterns were simulated and two dose levels, 2 Gy/fraction and 2 cGy/fraction, were used for simulations to study the robustness of this method against detector quantum noise. The algorithm was used to determine the breathing phases and this result was compared with the simulated breathing patterns. For the 2 Gy/fraction simulations, the respiration phases were accurately determined within one phase error in real time for most projections of the treatment, except for a few

  16. Evaluation of normalized metal artifact reduction (NMAR) in kVCT using MVCT prior images for radiotherapy treatment planning

    SciTech Connect

    Paudel, M. R.; Mackenzie, M.; Rathee, S.; Fallone, B. G.

    2013-08-15

    Purpose: To evaluate the metal artifacts in kilovoltage computed tomography (kVCT) images that are corrected using a normalized metal artifact reduction (NMAR) method with megavoltage CT (MVCT) prior images.Methods: Tissue characterization phantoms containing bilateral steel inserts are used in all experiments. Two MVCT images, one without any metal artifact corrections and the other corrected using a modified iterative maximum likelihood polychromatic algorithm for CT (IMPACT) are translated to pseudo-kVCT images. These are then used as prior images without tissue classification in an NMAR technique for correcting the experimental kVCT image. The IMPACT method in MVCT included an additional model for the pair/triplet production process and the energy dependent response of the MVCT detectors. An experimental kVCT image, without the metal inserts and reconstructed using the filtered back projection (FBP) method, is artificially patched with the known steel inserts to get a reference image. The regular NMAR image containing the steel inserts that uses tissue classified kVCT prior and the NMAR images reconstructed using MVCT priors are compared with the reference image for metal artifact reduction. The Eclipse treatment planning system is used to calculate radiotherapy dose distributions on the corrected images and on the reference image using the Anisotropic Analytical Algorithm with 6 MV parallel opposed 5 × 10 cm{sup 2} fields passing through the bilateral steel inserts, and the results are compared. Gafchromic film is used to measure the actual dose delivered in a plane perpendicular to the beams at the isocenter.Results: The streaking and shading in the NMAR image using tissue classifications are significantly reduced. However, the structures, including metal, are deformed. Some uniform regions appear to have eroded from one side. There is a large variation of attenuation values inside the metal inserts. Similar results are seen in commercially corrected image

  17. A Review of Radiotherapy-Induced Late Effects Research after Advanced Technology Treatments

    PubMed Central

    Newhauser, Wayne D.; de Gonzalez, Amy Berrington; Schulte, Reinhard; Lee, Choonsik

    2016-01-01

    The number of incident cancers and long-term cancer survivors is expected to increase substantially for at least a decade. Advanced technology radiotherapies, e.g., using beams of protons and photons, offer dosimetric advantages that theoretically yield better outcomes. In general, evidence from controlled clinical trials and epidemiology studies are lacking. To conduct these studies, new research methods and infrastructure will be needed. In the paper, we review several key research methods of relevance to late effects after advanced technology proton-beam and photon-beam radiotherapies. In particular, we focus on the determination of exposures to therapeutic and stray radiation and related uncertainties, with discussion of recent advances in exposure calculation methods, uncertainties, in silico studies, computing infrastructure, electronic medical records, and risk visualization. We identify six key areas of methodology and infrastructure that will be needed to conduct future outcome studies of radiation late effects. PMID:26904500

  18. A Review of Radiotherapy-Induced Late Effects Research after Advanced Technology Treatments.

    PubMed

    Newhauser, Wayne D; Berrington de Gonzalez, Amy; Schulte, Reinhard; Lee, Choonsik

    2016-01-01

    The number of incident cancers and long-term cancer survivors is expected to increase substantially for at least a decade. Advanced technology radiotherapies, e.g., using beams of protons and photons, offer dosimetric advantages that theoretically yield better outcomes. In general, evidence from controlled clinical trials and epidemiology studies are lacking. To conduct these studies, new research methods and infrastructure will be needed. In the paper, we review several key research methods of relevance to late effects after advanced technology proton-beam and photon-beam radiotherapies. In particular, we focus on the determination of exposures to therapeutic and stray radiation and related uncertainties, with discussion of recent advances in exposure calculation methods, uncertainties, in silico studies, computing infrastructure, electronic medical records, and risk visualization. We identify six key areas of methodology and infrastructure that will be needed to conduct future outcome studies of radiation late effects.

  19. Time delay measurement for linac based treatment delivery in synchronized respiratory gating radiotherapy

    SciTech Connect

    Jin Jianyue; Yin Fangfang

    2005-05-01

    A time delay in a respiratory gating system could cause an unexpected phase mismatch for synchronized gating radiotherapy. This study presents a method of identifying and measuring the time delay in a gating system. Various port films were taken for a motion phantom at different gating window levels with a very narrow window size. The time delay for the gating system was determined by comparing the motion curve (the position of a moving object versus the gating time) measured in the port films to the motion curve determined by the video cameras. The measured time delay for a linac-based gating system was 0.17{+-}0.03 s. This time delay could induce target missing if it was not properly taken into account for the synchronized gating radiotherapy. Measurement/verification of the time delay should be considered as an important part of the accepting/commissioning test before the clinical use of the gating system.

  20. Consideration of the radiation dose delivered away from the treatment field to patients in radiotherapy

    PubMed Central

    Taylor, Michael L.; Kron, Tomas

    2011-01-01

    Radiation delivery to cancer patients for radiotherapy is invariably accompanied by unwanted radiation to other parts of the patient’s body. Traditionally, considerable effort has been made to calculate and measure the radiation dose to the target as well as to nearby critical structures. Only recently has attention been focused also on the relatively low doses that exist far from the primary radiation beams. In several clinical scenarios, such doses have been associated with cardiac toxicity as well as an increased risk of secondary cancer induction. Out-of-field dose is a result of leakage and scatter and generally difficult to predict accurately. The present review aims to present existing data, from measurements and calculations, and discuss its implications for radiotherapy. PMID:21731221

  1. Evaluation of treatment outcomes of early-stage endometrial cancer radiotherapy: a single center experience.

    PubMed

    Demiral, S; Beyzadeoglu, M; Sager, O; Dincoglan, F; Uysal, B; Gamsiz, H; Akin, M; Turker, T; Dirican, B

    2014-01-01

    Postoperative adjuvant radiotherapy (RT) in the management of early stage endometrial cancer (EC) is still controversial. Here we report our institutional experience with patients who received postoperative RT for stage I-II EC over a period of 35 years and assess potential predictors of local recurrence (LR), distant metastasis (DM), and overall survival (OS). A total of 188 patients undergoing postoperative RT for stage IA-II EC between 1977 and 2012 were evaluated. Some 96 received median 46 Gy whole pelvic radiotherapy (WPRT) (range: 40-60 Gy), 37 were given WPRT with vaginal cuff therapy (VCT), and 55 received only VCT either with brachytherapy (BT) or stereotactic body radiotherapy (SBRT). Chemotherapy was given to 5 patients with uterine papillary serous carcinoma (UPSC). Logistic regression analysis was used to assess the effect of clinicopathological factors on LR, DM, and OS. Median follow-up time was 11 years (range: 1-35 years). At the time of analysis, 34 patients were not alive. Of the 15 patients with LR, 7 (46.7%) recurred in the vaginal stump, 5 (33.3%) in the pelvic region, and 3 (20%) in the paraaortic nodal region, while 12 had distant metastasis. UPSC histology (p=0.027), sole VCT (p=0.041), high histologic grade (p=0.034), and age≥71 (p=0.04) were poor prognostic factors on univariate analysis. In our patients receiving radiotherapy for early-stage EC, grade III disease and age≥71 were associated with shorter OS whereas UPSC histology was an independent predictor for both LR and DM.

  2. Dosimetric and radiobiological comparison of helical tomotherapy, forward-planned intensity-modulated radiotherapy and two-phase conformal plans for radical radiotherapy treatment of head and neck squamous cell carcinomas.

    PubMed

    Chatterjee, S; Willis, N; Locks, S M; Mott, J H; Kelly, C G

    2011-12-01

    The usual radical radiotherapy treatment prescribed for head and neck squamous cell carcinoma (HNSCC) is 70 Gy (in 2 Gy per fraction equivalent) administered to the high-risk target volume (TV). This can be planned using either a forward-planned photon-electron junction technique (2P) or a single-phase (1P) forward-planned technique developed in-house. Alternatively, intensity-modulated radiotherapy (IMRT) techniques, including helical tomotherapy (HT), allow image-guided inversely planned treatments. This study was designed to compare these three planning techniques with regards to TV coverage and the dose received by organs at risk. We compared the dose-volume histograms and conformity indices (CI) of the three planning processes in five patients with HNSCC. The tumour control probability (TCP), normal tissue complication probability (NTCP) and uncomplicated tumour control probability (UCP) were calculated for each of the 15 plans. In addition, we explored the radiobiological rationality of a dose-escalation strategy. The CI for the high-risk clinical TV (CTV1) in the 5 patients were 0.78, 0.76, 0.82, 0.72 and 0.81 when HT was used; 0.58, 0.56, 0.47, 0.35 and 0.60 for the single-phase forward-planned technique and 0.46, 0.36, 0.29, 0.22 and 0.49 for the two-phase technique. The TCP for CTV1 with HT were 79.2%, 85.2%, 81.1%, 83.0% and 53.0%; for single-phase forward-planned technique, 76.5%, 86.9%, 73.4%, 81.8% and 31.8% and for the two-phase technique, 38.2%, 86.2%, 42.7%, 0.0% and 3.4%. Dose escalation using HT confirmed the radiobiological advantage in terms of TCP. TCP for the single-phase plans was comparable to that of HT plans, whereas that for the two-phase technique was lower. Centres that cannot provide IMRT for the radical treatment of all patients could implement the single-phase technique as standard to attain comparable TCP. However, IMRT produced better UCP, thereby enabling the exploration of dose escalation.

  3. Progressive muscle atrophy and weakness after treatment by mantle field radiotherapy in Hodgkin lymphoma survivors.

    PubMed

    van Leeuwen-Segarceanu, Elena M; Dorresteijn, Lucille D A; Pillen, Sigrid; Biesma, Douwe H; Vogels, Oscar J M; van Alfen, Nens

    2012-02-01

    To describe the damage to the muscles and propose a pathophysiologic mechanism for muscle atrophy and weakness after mantle field radiotherapy in Hodgkin lymphoma (HL) survivors. We examined 12 patients treated by mantle field radiotherapy between 1969 and 1998. Besides evaluation of their symptoms, the following tests were performed: dynamometry; ultrasound of the sternocleidomastoid, biceps, and antebrachial flexor muscles; and needle electromyography of the neck, deltoid, and ultrasonographically affected arm muscles. Ten patients (83%) experienced neck complaints, mostly pain and muscle weakness. On clinical examination, neck flexors were more often affected than neck extensors. On ultrasound, the sternocleidomastoid was severely atrophic in 8 patients, but abnormal echo intensity was seen in only 3 patients. Electromyography of the neck muscles showed mostly myogenic changes, whereas the deltoid, biceps, and antebrachial flexor muscles seemed to have mostly neurogenic damage. Many patients previously treated by mantle field radiotherapy develop severe atrophy and weakness of the neck muscles. Neck muscles within the radiation field show mostly myogenic damage, and muscles outside the mantle field show mostly neurogenic damage. The discrepancy between echo intensity and atrophy suggests that muscle damage is most likely caused by an extrinsic factor such as progressive microvascular fibrosis. This is also presumed to cause damage to nerves within the radiated field, resulting in neurogenic damage of the deltoid and arm muscles. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Progressive Muscle Atrophy and Weakness After Treatment by Mantle Field Radiotherapy in Hodgkin Lymphoma Survivors

    SciTech Connect

    Leeuwen-Segarceanu, Elena M. van; Dorresteijn, Lucille D.A.; Pillen, Sigrid; Biesma, Douwe H.; Vogels, Oscar J.M.; Alfen, Nens van

    2012-02-01

    Purpose: To describe the damage to the muscles and propose a pathophysiologic mechanism for muscle atrophy and weakness after mantle field radiotherapy in Hodgkin lymphoma (HL) survivors. Methods and Materials: We examined 12 patients treated by mantle field radiotherapy between 1969 and 1998. Besides evaluation of their symptoms, the following tests were performed: dynamometry; ultrasound of the sternocleidomastoid, biceps, and antebrachial flexor muscles; and needle electromyography of the neck, deltoid, and ultrasonographically affected arm muscles. Results: Ten patients (83%) experienced neck complaints, mostly pain and muscle weakness. On clinical examination, neck flexors were more often affected than neck extensors. On ultrasound, the sternocleidomastoid was severely atrophic in 8 patients, but abnormal echo intensity was seen in only 3 patients. Electromyography of the neck muscles showed mostly myogenic changes, whereas the deltoid, biceps, and antebrachial flexor muscles seemed to have mostly neurogenic damage. Conclusions: Many patients previously treated by mantle field radiotherapy develop severe atrophy and weakness of the neck muscles. Neck muscles within the radiation field show mostly myogenic damage, and muscles outside the mantle field show mostly neurogenic damage. The discrepancy between echo intensity and atrophy suggests that muscle damage is most likely caused by an extrinsic factor such as progressive microvascular fibrosis. This is also presumed to cause damage to nerves within the radiated field, resulting in neurogenic damage of the deltoid and arm muscles.

  5. Successful Treatment of Advanced Primary Cutaneous Apocrine Carcinoma on the Scrotum with Systemic Chemotherapy and Radiotherapy Followed by Denosumab

    PubMed Central

    Furudate, Sadanori; Fujimura, Taku; Tsukada, Akira; Sato, Yota; Hidaka, Takanori; Tanita, Kayo; Kambayashi, Yumi; Haga, Takahiro; Hashimoto, Akira; Aiba, Setsuya

    2017-01-01

    Primary cutaneous apocrine carcinoma (PCAC) is a rare and highly aggressive cutaneous adnexal type of tumor that has a high metastasis rate and a poor prognosis. Although there are several case reports describing the successful treatment of PCAC with chemoradiotherapy or molecular targeting therapy, no standard therapy for the treatment of advanced PCAC has been established yet. Since receptor activator of nuclear factor kappa-B ligand (RANKL) is expressed in cancers of apocrine origin, leading to immunosuppression at the tumor site, we hypothesized that targeting RANKL with denosumab might be useful for the treatment of PCAC. In this report, we describe a case with advanced PCAC on the scrotum successfully treated with systemic chemotherapy using carboplatin and paclitaxel, and radiotherapy followed by denosumab. PMID:28203164

  6. Radiotherapy in the treatment of mucosal melanoma of the upper aerodigestive tract: Analysis of 74 cases. A Rare Cancer Network study

    SciTech Connect

    Krengli, Marco . E-mail: krengli@tera.it; Masini, Laura; Kaanders, Johannes; Maingon, Philippe; Oei, Swan Bing; Zouhair, Abderrahim; Ozyar, Enis; Roelandts, Martine; Amichetti, Maurizio; Bosset, Mathieu; Mirimanoff, Rene-Olivier

    2006-07-01

    Purpose: To retrospectively analyze a series of mucosal melanoma of the upper aerodigestive tract to determine the prognostic factors and contribute to understanding the role of radiotherapy in the therapeutic strategy. Methods and Materials: Seventy-four patients were analyzed. The most frequent locations were nasal and oral, in 31 patients (41.9%) and 12 patients (16.2%), respectively. Sixty-three patients (85.1%) were in Stage I, 5 (6.8%) in Stage II, and 6 (8.1%) in Stage III. Treatment consisted of surgery in 17 patients (23.0%), surgery and radiotherapy in 42 (56.8%), radiotherapy in 11 (14.9%), and chemo-immunotherapy in 4 (5.4%). Median follow-up was 20 months. Results: Local control at 3 years was 57% after surgery alone and 71% after surgery and radiotherapy. Overall and disease-free survival rates, respectively, were 41% and 31% at 3 years and 14% and 22% at 10 years. After univariate analysis, female gender, melanosis, tumor size {<=}3 cm, Stage I, postoperative radiotherapy, and complete remission were favorable prognostic factors. Stage I and melanosis were confirmed by multivariate analysis. Conclusions: Local control was improved by postoperative radiotherapy, despite survival being as poor as in other published series. Stage I and melanosis at diagnosis were the most favorable prognostic factors.

  7. Does the Couse of Astragalus-Containing Chinese Herbal Prescriptions and Radiotherapy Benefit to Non-Small-Cell Lung Cancer Treatment: A Meta-Analysis of Randomized Trials

    PubMed Central

    Zhou, Xianmei; Wang, Qian; Zhao, Yang

    2013-01-01

    Background. Radiotherapy has been widely used for non-small-cell lung cancer (NSCLC), while its low efficacy and high toxicity raise big concerns. Astragalus (as a monarch drug)-containing Chinese herbal prescriptions and radiotherapy were frequently coused for NSCLC in China; however, the effects were not systematically analyzed. Objective. To evaluate the benefits of Astragalus-containing Chinese herbal prescriptions combined with radiotherapy for NSCLC. Methods. The randomized controlled trials involving NSCLC treatment with Astragalus-containing Chinese herbal prescriptions combined with radiotherapy were searched. The Review Manager 5.1 software was employed for data analysis. Funnel plot and Egger's test were applied to evaluate publication bias. Results. 29 eligible studies met our criteria. Of the studies, 8, 6, and 4 reported reduced risk of death at one year, two years, and three years, respectively. 26 studies revealed amended tumor response. Six studies showed improved Karnofsky performance status. Among the studies, 14 and 18 displayed a lowered white blood cells (WBC) toxicity and an ameliorated radiation pneumonia, respectively. Conclusion. Couse of Astragalus-containing Chinese herbal prescriptions and radiotherapy may benefit the patients with NSCLC via increasing the therapeutic effectiveness and reducing the toxicity of radiotherapy. To confirm the exact merits, further rigorously designed trials are warranted. PMID:24454494

  8. Perspectives on the combination of radiotherapy and targeted therapy with DNA repair inhibitors in the treatment of pancreatic cancer

    PubMed Central

    Yang, Shih-Hung; Kuo, Ting-Chun; Wu, Hsu; Guo, Jhe-Cyuan; Hsu, Chiun; Hsu, Chih-Hung; Tien, Yu-Wen; Yeh, Kun-Huei; Cheng, Ann-Lii; Kuo, Sung-Hsin

    2016-01-01

    Pancreatic cancer is highly lethal. Current research that combines radiation with targeted therapy may dramatically improve prognosis. Cancerous cells are characterized by unstable genomes and activation of DNA repair pathways, which are indicated by increased phosphorylation of numerous factors, including H2AX, ATM, ATR, Chk1, Chk2, DNA-PKcs, Rad51, and Ku70/Ku80 heterodimers. Radiotherapy causes DNA damage. Cancer cells can be made more sensitive to the effects of radiation (radiosensitization) through inhibition of DNA repair pathways. The synergistic effects, of two or more combined non-lethal treatments, led to co-administration of chemotherapy and radiosensitization in BRCA-defective cells and patients, with promising results. ATM/Chk2 and ATR/Chk1 pathways are principal regulators of cell cycle arrest, following DNA double-strand or single-strand breaks. DNA double-stranded breaks activate DNA-dependent protein kinase, catalytic subunit (DNA-PKcs). It forms a holoenzyme with Ku70/Ku80 heterodimers, called DNA-PK, which catalyzes the joining of nonhomologous ends. This is the primary repair pathway utilized in human cells after exposure to ionizing radiation. Radiosensitization, induced by inhibitors of ATM, ATR, Chk1, Chk2, Wee1, PP2A, or DNA-PK, has been demonstrated in preclinical pancreatic cancer studies. Clinical trials are underway. Development of agents that inhibit DNA repair pathways to be clinically used in combination with radiotherapy is warranted for the treatment of pancreatic cancer. PMID:27621574

  9. Evaluation of dose calculations accuracy of a commercial treatment planning system for the head and neck region in radiotherapy.

    PubMed

    Bahreyni Toossi, Mohammad Taghi; Farhood, Bagher; Soleymanifard, Shokouhozaman

    2017-01-01

    The objective was to quantify dose calculation accuracy of TiGRT TPS for head and neck region in radiotherapy. In radiotherapy of head and neck cancers, treatment planning is difficult, due to the complex shape of target volumes and also to spare critical and normal structures. These organs are often very near to the target volumes and have low tolerance to radiation. In this regard, dose calculation accuracy of treatment planning system (TPS) must be high enough. Thermoluminescent dosimeter-100 (TLD-100) chips were used within RANDO phantom for dose measurement. TiGRT TPS was also applied for dose calculation. Finally, difference between measured doses (Dmeas) and calculated doses (Dcalc) was obtained to quantify the dose calculation accuracy of the TPS at head and neck region. For in-field regions, in some points, the TiGRT TPS overestimated the dose compared to the measurements and for other points underestimated the dose. For outside field regions, the TiGRT TPS underestimated the dose compared to the measurements. For most points, the difference values between Dcalc and Dmeas for the in-field and outside field regions were less than 5% and 40%, respectively. Due to the sensitive structures to radiation in the head and neck region, the dose calculation accuracy of TPSs should be sufficient. According to the results of this study, it is concluded that the accuracy of dose calculation of TiGRT TPS is enough for in-field and out of field regions.

  10. Effects of postoperative adjuvant chemotherapy and radiotherapy on ovarian function in women undergoing treatment for soft tissue sarcoma

    SciTech Connect

    Shamberger, R.C.; Sherins, R.J.; Ziegler, J.L.; Glatstein, E.; Rosenberg, S.A.

    1981-12-01

    Ovarian function was evaluated in 11 women 16 to 43 years of age at treatment who received doxorubicin, cyclophosphamide, and high doses of methotrexate with or without radiotherapy in adjuvant therapy of soft tissue sarcoma. Five women (16-33 yr old) who received chemotherapy alone or combined with radiotherapy only at sites distant from the ovaries (chest wall, thigh, and leg) had minimal menstrual irregularities or temporary cessation of menses during therapy; cyclic menses returned promptly after therapy. Gonadotropin levels (expressed as means +/- SD (follicle-stimulating hormone (FSH), 10 +/- 5 mlU/ml; luteinizing hormone (LH), 10 +/- 4 mlU/ml) and 17 beta-estradiol (E2) levels (means +/- SD, 208 +/- 147 pg/ml) were normal. By contrast, 4 older women (ages 36-43 yr) who received similar treatment developed persistent amenorrhea with postmenopausal levels of gonadotropin (FSH, 108 +/- 29 mlU/ml; LH, 72 +/- 19 mlU/ml) and E2 (19 +/- 8 pg/ml). Two additional women (ages 21 and 39 yr) who received radiation (7,000 rad) to the pelvis plus chemotherapy developed prompt cessation of menses and became functional castrates (FSH, 77 and 80 mlU/ml; LH, 40 and 58 mlU/ml; E2, 10 and 19 pg/ml). However, this result would be expected from the radiation dose alone. The data demonstrated that ovarian dysfunction may follow the use of doxorubicin, cyclophosphamide, and high doses of methotrexate and that the injury is age related.

  11. Raw liquid waste treatment process

    NASA Technical Reports Server (NTRS)

    Humphrey, Marshall F. (Inventor)

    1980-01-01

    A raw sewage treatment process is disclosed in which substantially all the non-dissolved matter, which is suspended in the sewage water is first separated from the water, in which at least organic matter is dissolved. The non-dissolved material is pyrolyzed to form an activated carbon and ash material without the addition of any conditioning agents. The activated carbon and ash material is added to the water from which the non-dissolved matter was removed. The activated carbon and ash material absorbs organic matter and heavy metal ions, it is believed, are dissolved in the water and is thereafter supplied in a counter current flow direction and combined with the incoming raw sewage to facilitate the separation of the non-dissolved settleable materials from the sewage water. The used carbon and ash material together with the non-dissolved matter which was separated from the sewage water are pyrolyzed to form the activated carbon and ash material.

  12. Monte Carlo as a four-dimensional radiotherapy treatment-planning tool to account for respiratory motion

    NASA Astrophysics Data System (ADS)

    Keall, P. J.; Siebers, J. V.; Joshi, S.; Mohan, R.

    2004-08-01

    Four-dimensional (4D) radiotherapy is the explicit inclusion of the temporal changes in anatomy during the imaging, planning and delivery of radiotherapy. Temporal anatomic changes can occur for many reasons, though the focus of the current investigation was respiration motion for lung tumours. The aims of the current research were first to develop a 4D Monte Carlo methodology and second to apply this technique to an existing 4D treatment plan. A 4D CT scan consisting of a series of 3D CT image sets acquired at different respiratory phases was used. Deformable image registration was performed to map each CT set from the end-inhale respiration phase to the CT image sets corresponding with subsequent respiration phases. This deformable registration allowed the contours drawn on the end-inhale CT to be automatically drawn on the other respiratory phase CT image sets. A treatment plan was created on the end-inhale CT image set and then automatically created on each of the 3D CT image sets corresponding with subsequent respiration phases, based on the beam arrangement and dose prescription in the end-inhale plan. Dose calculation using Monte Carlo was simultaneously performed on each of the N (=8) 3D image sets with 1/N fewer particles per calculation than for a 3D plan. The dose distribution from each respiratory phase CT image set was mapped back to the end-inhale CT image set for analysis. This use of deformable image registration to merge all the statistically noisy dose distributions back onto one CT image set effectively yielded a 4D Monte Carlo calculation with a statistical uncertainty equivalent to a 3D calculation, with a similar calculation time for the 3D and 4D methods. Monte Carlo as a dose calculation tool for 4D radiotherapy planning has two advantages: (1) higher accuracy for calculation in electronic disequilibrium conditions, such as those encountered during lung radiotherapy, and (2) if deformable image registration is used, the calculation time for

  13. Phase I/II trial evaluating carbon ion radiotherapy for the treatment of recurrent rectal cancer: the PANDORA-01 trial.

    PubMed

    Combs, Stephanie E; Kieser, Meinhard; Habermehl, Daniel; Weitz, Jürgen; Jäger, Dirk; Fossati, Piero; Orrechia, Roberto; Engenhart-Cabillic, Rita; Pötter, Richard; Dosanjh, Manjit; Jäkel, Oliver; Büchler, Markus W; Debus, Jürgen

    2012-04-03

    Treatment standard for patients with rectal cancer depends on the initial staging and includes surgical resection, radiotherapy as well as chemotherapy. For stage II and III tumors, radiochemotherapy should be performed in addition to surgery, preferentially as preoperative radiochemotherapy or as short-course hypofractionated radiation. Advances in surgical approaches, especially the establishment of the total mesorectal excision (TME) in combination with sophisticated radiation and chemotherapy have reduced local recurrence rates to only few percent. However, due to the high incidence of rectal cancer, still a high absolute number of patients present with recurrent rectal carcinomas, and effective treatment is therefore needed.Carbon ions offer physical and biological advantages. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increase relative biological effectiveness (RBE), which can be calculated between 2 and 5 depending on the cell line as well as the endpoint analyzed.Japanese data on the treatment of patients with recurrent rectal cancer previously not treated with radiation therapy have shown local control rates of carbon ion treatment superior to those of surgery. Therefore, this treatment concept should also be evaluated for recurrences after radiotherapy, when dose application using conventional photons is limited. Moreover, these patients are likely to benefit from the enhanced biological efficacy of carbon ions. In the current Phase I/II-PANDORA-01-Study the recommended dose of carbon ion radiotherapy for recurrent rectal cancer will be determined in the Phase I part, and feasibilty and progression-free survival will be assessed in the Phase II part of the study.Within the Phase I part, increasing doses from 12 × 3 Gy E to 18 × 3 Gy E will be applied.The primary endpoint in the Phase

  14. Comparative evaluation of a novel 3D segmentation algorithm on in-treatment radiotherapy cone beam CT images

    NASA Astrophysics Data System (ADS)

    Price, Gareth; Moore, Chris

    2007-03-01

    Image segmentation and delineation is at the heart of modern radiotherapy, where the aim is to deliver as high a radiation dose as possible to a cancerous target whilst sparing the surrounding healthy tissues. This, of course, requires that a radiation oncologist dictates both where the tumour and any nearby critical organs are located. As well as in treatment planning, delineation is of vital importance in image guided radiotherapy (IGRT): organ motion studies demand that features across image databases are accurately segmented, whilst if on-line adaptive IGRT is to become a reality, speedy and correct target identification is a necessity. Recently, much work has been put into the development of automatic and semi-automatic segmentation tools, often using prior knowledge to constrain some grey level, or derivative thereof, interrogation algorithm. It is hoped that such techniques can be applied to organ at risk and tumour segmentation in radiotherapy. In this work, however, we make the assumption that grey levels do not necessarily determine a tumour's extent, especially in CT where the attenuation coefficient can often vary little between cancerous and normal tissue. In this context we present an algorithm that generates a discontinuity free delineation surface driven by user placed, evidence based support points. In regions of sparse user supplied information, prior knowledge, in the form of a statistical shape model, provides guidance. A small case study is used to illustrate the method. Multiple observers (between 3 and 7) used both the presented tool and a commercial manual contouring package to delineate the bladder on a serially imaged (10 cone beam CT volumes ) prostate patient. A previously presented shape analysis technique is used to quantitatively compare the observer variability.

  15. 4D ML reconstruction as a tool for volumetric PET-based treatment verification in ion beam radiotherapy

    SciTech Connect

    De Bernardi, E.; Ricotti, R.; Riboldi, M.; Baroni, G.; Parodi, K.; Gianoli, C.

    2016-02-15

    Purpose: An innovative strategy to improve the sensitivity of positron emission tomography (PET)-based treatment verification in ion beam radiotherapy is proposed. Methods: Low counting statistics PET images acquired during or shortly after the treatment (Measured PET) and a Monte Carlo estimate of the same PET images derived from the treatment plan (Expected PET) are considered as two frames of a 4D dataset. A 4D maximum likelihood reconstruction strategy was adapted to iteratively estimate the annihilation events distribution in a reference frame and the deformation motion fields that map it in the Expected PET and Measured PET frames. The outputs generated by the proposed strategy are as follows: (1) an estimate of the Measured PET with an image quality comparable to the Expected PET and (2) an estimate of the motion field mapping Expected PET to Measured PET. The details of the algorithm are presented and the strategy is preliminarily tested on analytically simulated datasets. Results: The algorithm demonstrates (1) robustness against noise, even in the worst conditions where 1.5 × 10{sup 4} true coincidences and a random fraction of 73% are simulated; (2) a proper sensitivity to different kind and grade of mismatches ranging between 1 and 10 mm; (3) robustness against bias due to incorrect washout modeling in the Monte Carlo simulation up to 1/3 of the original signal amplitude; and (4) an ability to describe the mismatch even in presence of complex annihilation distributions such as those induced by two perpendicular superimposed ion fields. Conclusions: The promising results obtained in this work suggest the applicability of the method as a quantification tool for PET-based treatment verification in ion beam radiotherapy. An extensive assessment of the proposed strategy on real treatment verification data is planned.

  16. Analysis of a large number of clinical studies for breast cancer radiotherapy: estimation of radiobiological parameters for treatment planning

    NASA Astrophysics Data System (ADS)

    Guerrero, M.; Li, X. Allen

    2003-10-01

    Numerous studies of early-stage breast cancer treated with breast conserving surgery (BCS) and radiotherapy (RT) have been published in recent years. Both external beam radiotherapy (EBRT) and/or brachytherapy (BT) with different fractionation schemes are currently used. The present RT practice is largely based on empirical experience and it lacks a reliable modelling tool to compare different RT modalities or to design new treatment strategies. The purpose of this work is to derive a plausible set of radiobiological parameters that can be used for RT treatment planning. The derivation is based on existing clinical data and is consistent with the analysis of a large number of published clinical studies on early-stage breast cancer. A large number of published clinical studies on the treatment of early breast cancer with BCS plus RT (including whole breast EBRT with or without a boost to the tumour bed, whole breast EBRT alone, brachytherapy alone) and RT alone are compiled and analysed. The linear quadratic (LQ) model is used in the analysis. Three of these clinical studies are selected to derive a plausible set of LQ parameters. The potential doubling time is set a priori in the derivation according to in vitro measurements from the literature. The impact of considering lower or higher Tpot is investigated. The effects of inhomogeneous dose distributions are considered using clinically representative dose volume histograms. The derived LQ parameters are used to compare a large number of clinical studies using different regimes (e.g., RT modality and/or different fractionation schemes with different prescribed dose) in order to validate their applicability. The values of the equivalent uniform dose (EUD) and biologically effective dose (BED) are used as a common metric to compare the biological effectiveness of each treatment regime. We have obtained a plausible set of radiobiological parameters for breast cancer: agr = 0.3 Gy-1, agr/bgr = 10 Gy and sub

  17. The Relationship Between Local Recurrence and Radiotherapy Treatment Volume for Soft Tissue Sarcomas Treated With External Beam Radiotherapy and Function Preservation Surgery

    SciTech Connect

    Dickie, Colleen I.; Griffin, Anthony M.; Parent, Amy L.; Chung, Peter W.M.; Catton, Charles N.; Svensson, Jon; Ferguson, Peter C.; Wunder, Jay S.; Bell, Robert S.; Sharpe, Michael B.; O'Sullivan, Brian

    2012-03-15

    Purpose: To examine the geometric relationship between local recurrence (LR) and external beam radiotherapy (RT) volumes for soft-tissue sarcoma (STS) patients treated with function-preserving surgery and RT. Methods and Materials: Sixty of 768 (7.8%) STS patients treated with combined therapy within our institution from 1990 through 2006 developed an LR. Thirty-two received preoperative RT, 16 postoperative RT, and 12 preoperative RT plus a postoperative boost. Treatment records, RT simulation images, and diagnostic MRI/CT data sets of the original and LR disease were retrospectively compared. For LR location analysis, three RT target volumes were defined according to the International Commission on Radiation Units and Measurements 29 as follows: (1) the gross tumor or operative bed; (2) the treatment volume (TV) extending 5 cm longitudinally beyond the tumor or operative bed unless protected by intact barriers to spread and at least 1-2 cm axially (the TV was enclosed by the isodose curve representing the prescribed target absorbed dose [TAD] and accounted for target/patient setup uncertainty and beam characteristics), and (3) the irradiated volume (IRV) that received at least 50% of the TAD, including the TV. LRs were categorized as developing in field within the TV, marginal (on the edge of the IRV), and out of field (occurring outside of the IRV). Results: Forty-nine tumors relapsed in field (6.4% overall). Nine were out of field (1.1% overall), and 2 were marginal (0.3% overall). Conclusions: The majority of STS tumors recur in field, indicating that the incidence of LR may be affected more by differences in biologic and molecular characteristics rather than aberrations in RT dose or target volume coverage. In contrast, only two patients relapsed at the IRV boundary, suggesting that the risk of a marginal relapse is low when the TV is appropriately defined. These data support the accurate delivery of optimal RT volumes in the most precise way using advanced

  18. Burden of cancer and projections for 2016, Indian scenario: gaps in the availability of radiotherapy treatment facilities.

    PubMed

    Murthy, N S; Chaudhry, Kishore; Rath, G K

    2008-01-01

    Plausible projections of future burden of cancer in terms of incident cases and requirement of radiotherapy treatment facilities at the national and state level are useful aids in planning of cancer control activities. The present communication attempts to provide a scenario for cancer in India during the year 2001 and its likely change by 2016 for al