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David J Gladstone - One of the best experts on this subject based on the ideXlab platform.
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improving treatment geometries in total skin Electron Therapy experimental investigation of linac angles and floor scatter dose contributions using cherenkov imaging
Medical Physics, 2018Co-Authors: Jacqueline M Andreozzi, Irwin I Tendler, Lesley A Jarvis, Brian W Pogue, Petr Brůža, K Mooney, Jochen Cammin, David J GladstoneAbstract:PURPOSE The purpose of this study was to identify the optimal treatment geometry for total skin Electron Therapy (TSET) using a new optimization metric from Cherenkov image analysis, and to investigate the sensitivity of the Cherenkov imaging method to floor scatter effects in this unique treatment setup. METHODS Cherenkov imaging using an intensified charge coupled device (ICCD) was employed to measure the relative surface dose distribution as a 2D image in the total skin Electron treatment plane. A 1.2 m × 2.2 m × 1 cm white polyethylene sheet was placed vertically at a source to surface distance (SSD) of 300 cm, and irradiated with 6 MeV high dose rate TSET beams. The linear accelerator coordinate system used stipulates 0° is the bottom of the gantry arc, and progresses counterclockwise so that gantry angle 270° produces a horizontal beam orthogonal to the treatment plane. First, all unique pairs of treatment beams were analyzed to determine the performance of the currently recommended symmetric treatment angles (±20° from the horizontal), compared to treatment geometries unconstrained to upholding gantry angle symmetry. This was performed on two medical linear accelerators (linacs). Second, the extent of the floor scatter contributions to measured surface dose at the extended SSD required for TSET were imaged using three gantry angles of incidence: 270° (horizontal), 253° (-17°), and 240° (-30°). Images of the surface dose profile at each angle were compared to the standard concrete floor when steel plates, polyvinyl chloride (PVC), and solid water were placed on the ground at the base of the treatment plane. Postprocessing of these images allowed for comparison of floor material-based scatter profiles with previously published simulation results. RESULTS Analysis of the symmetric treatment geometry (270 ± 20°) and the identified optimal treatment geometry (270 + 23° and 270 - 17°) showed a 16% increase in the 90% isodose area for the latter field pair on the first linac. The optimal asymmetric pair for the second linac (270 + 25° and 270 - 17°) provided a 52% increase in the 90% isodose area when compared to the symmetric geometry. Difference images between Cherenkov images captured with test materials (steel, PVC, and solid water) and the control (concrete floor) demonstrated relative changes in the two-dimensional (2D) dose profile over a 1 × 1.9 m region of interest (ROI) that were consistent with published simulation data. Qualitative observation of the residual images demonstrates localized increases and decreases with respect to the change in floor material and gantry angle. The most significant changes occurred when the beam was most directly impinging the floor (gantry angle 240°, horizontal -30°), where the PVC floor material decreased scatter dose by 1-3% in 7.2% of the total ROI area, and the steel plate increased scatter dose by 1-3% in 7.0% of the total ROI area. CONCLUSIONS An updated Cherenkov imaging method identified asymmetric, machine-dependent TSET field angle pairs that provided much larger 90% isodose areas than the commonly adopted symmetric geometry suggested by Task Group 30 Report 23. A novel demonstration of scatter dose Cherenkov imaging in the TSET field was established.
J Lehmann - One of the best experts on this subject based on the ideXlab platform.
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monte carlo treatment planning for molecular targeted radioTherapy within the minerva system
Physics in Medicine and Biology, 2005Co-Authors: David W. Nigg, J Lehmann, Christine Hartmann L Siantar, D E Wessol, C A Wemple, J J Cogliati, Tom Daly, Marie Anne DescalleAbstract: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 drug pharmacokinetics in MTR can only be properly accounted for by image-based, patient-specific treatment planning, as has been common in external beam radiation Therapy for many years. MINERVA offers 3D Monte Carlo-based MTR treatment planning as its first integrated operational capability. The new MINERVA system will ultimately incorporate capabilities for a comprehensive list of radiation therapies. In progress are modules for external beam photon-Electron Therapy and boron neutron capture Therapy (BNCT). BrachyTherapy and proton Therapy are planned. Through the open application programming interface (API), other groups can add their own modules and share them with the community.
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monte carlo treatment planning for molecular targeted radioTherapy within the minerva system
Presented at: Current Topics in Monte Carlo Treatment Planning Advanced Workshop Montreal Canada May 03 - May 05 2004, 2004Co-Authors: J Lehmann, David W. Nigg, Christine Hartmann L Siantar, D E Wessol, C A Wemple, J J Cogliati, Tom Daly, Marie Anne Descalle, T Flickinger, David PletcherAbstract: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 can only be properly accounted for by image-based, patient-specific treatment planning as has been common in external beam radiation Therapy for many years. MINERVA offers 3D Monte Carlo based MTR treatment planning as its first integrated operational capability. The new MINERVA system will ultimately incorporate capabilities for a comprehensive list of radiation therapies. In progress are modules for external beam photon-Electron Therapy and Boron Neutron Capture Therapy (BNCT). BrachyTherapy and ProtonTherapy are planned. Through the open Application Programming Interface (API) other groups can add their own modules and share them with the community.
L Marmiroli - One of the best experts on this subject based on the ideXlab platform.
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in vivo ebt radiochromic film dosimetry of Electron beam for total skin Electron Therapy tset
Physica Medica, 2007Co-Authors: A Bufacchi, A Carosi, N Adorante, Delle S Canne, T Malatesta, R Capparella, R Fragomeni, A Bonanni, M Leone, L MarmiroliAbstract:Abstract EBT radiochromic films were used to determine skin-dose maps for patients undergone Total Skin Electron Therapy (TSET). Gafchromic EBT radiochromic film is one of the newest radiation-induced auto-developing photon and Electron-beam analysis films available for therapeutic radiation dosimetry in radioTherapy applications. EBT films can be particularly useful in TSET; due to patient morphology, underdosed regions typically occur, and the radiochromic film represents a suitable candidate for monitoring them. In this study, TSET was applied to treat cutaneous T-cell lymphoma. The technique for TSET was implemented by using an Electron beam with a nominal energy of 6 MeV. The patient was treated in a standing position using dual angled fields in order to obtain the greatest dose uniformity along the patient's longitudinal axis. The Electron beam energy was degraded by a PMMA filter. The in vivo dose distribution was determined through the use of EBT films, as well as of thermoluminescent dosimeters for comparison (TLDs). EBT results showed a reasonable agreement with TLDs data.
Joachim Yahalom - One of the best experts on this subject based on the ideXlab platform.
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radiation Therapy for leukemia cutis
Practical radiation oncology, 2011Co-Authors: Richard L Bakst, Joachim YahalomAbstract:Abstract Purpose Leukemia cutis (LC) is the infiltration of the epidermis, dermis, or subcutis by neoplastic leukocytes, resulting in clinically identifiable cutaneous lesions. Electron-based radiation Therapy (RT) is often used in the treatment of LC; however, modern studies of RT are lacking. We reviewed our experience to analyze treatment response, disease control, and toxicity associated with RT in order to develop treatment recommendations for patients with LC. Methods and Materials Fifteen patients who underwent treatment for LC at our institution from November 1994 to August 2009 were identified and their medical records were reviewed and analyzed. Results LC presented after a median of 2 (range 0-24) months from acute myeloid leukemia diagnosis. Median survival from time of LC presentation was 23 months (range 0.5-137 months). Thirteen courses of radiation were administered to 12 patients: 9 total skin Electron beam (TSEB) Therapy and 4 focal treatments. Of patients receiving TSEB, 89% had diffuse LC involvement and 67% were in marrow remission. By contrast, only 25% of patients receiving focal Therapy had diffuse LC involvement and only 25% were in marrow remission. Median TSEB dose was 1600 (range 600-2400) cGy. Fifty percent of patients had a complete response to RT but 1-year local control was only 33%. All patients who developed a skin relapse either had active marrow disease at the time of RT or marrow recurrence shortly thereafter. Median survival since RT was 5 (range 0.5-136) months. RT was well tolerated without significant acute effects; however, 1 patient receiving chemoTherapy developed radiation recall 1 month after RT. Conclusions Patients with LC have aggressive disease with few long-term survivors. Definitive treatment with TSEB should be utilized only in cases of marrow remission with focal Electron Therapy reserved for palliation of symptomatic lesions. Long-term prognosis and durable cutaneous remission is dependent on systemic disease control.
Natia Esiashvili - One of the best experts on this subject based on the ideXlab platform.
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total skin Electron Therapy for cutaneous t cell lymphoma using a modern dual field rotational technique
International Journal of Radiation Oncology Biology Physics, 2015Co-Authors: T R Heumann, Natia Esiashvili, Sareeta Parker, Jeffrey M Switchenko, A Dhabbaan, Michael Goodman, Mary Jo Lechowicz, Christopher R Flowers, Mohammad K KhanAbstract:Purpose To report our experience with rotational total skin Electron irradiation (RTSEI) in cutaneous T-cell lymphoma (CTCL), and to examine response by disease stage and race. Methods and Materials We reviewed our outcomes for 68 CTCL patients who received RTSEI (≥30 Gy) from 2000 to 2013. Primary outcomes were complete clinical response (CCR), recurrence-free survival (RFS), and overall survival (OS). Using log–rank tests and Cox proportional hazards, OS and RFS were compared across tumor stages at time of RTSEI with further racial subgroup analysis. Results Median age at diagnosis and at time of radiation was 52 and 56 years, respectively. Median follow-up was 5.1 years, 49% were African American, and 49% were female. At time of treatment, 18, 37, and 13 patients were T stage 2, 3, and 4, respectively. At 6 weeks after RTSEI, overall CCR was 82% (88%, 83%, and 69% for T2, T3, and T4, respectively). Median RFS was 11 months for all patients and 14, 10, and 12 months for stage T2, T3, and T4, respectively. Tumor stage was not associated with RFS or CCR. Maintenance Therapy after RTSEI was associated with improved RFS in both crude and multivariable analysis, controlling for T stage. Median OS was 76 months (91 and 59 months for T3 and T4, respectively). With the exception of improved OS in African Americans compared with whites at stage T2, race was not associated with CCR, RFS, or OS. Conclusions These results represent the largest RTSEI clinical outcomes study in the modern era using a dual-field rotational technique. Our observed response rates match or improve upon the standard set by previous outcome studies using conventional TSEI techniques, despite a large percentage of advanced CTCL lesions in our cohort. We found that clinical response after RTSEI did not seem to be affected by T stage or race.
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role of total skin Electron beam Therapy for leukemia cutis in pediatric patients
Pediatric Blood & Cancer, 2008Co-Authors: Joseph M Pepek, Arnold C Paulino, Michael Briones, Robert B Marcus, Natia EsiashviliAbstract:The role of radiation Therapy for those with leukemia cutis, particularly pediatric patients, remains unclear. This report describes the first two cases of disseminated leukemia cutis in adolescents treated with total skin Electron beam Therapy. Both patients had resolution of their skin disease and significant palliation of symptoms. Total skin Electron irradiation is an option for adolescents suffering from significant extramedullary leukemia involving the skin. While it is uncertain if this treatment has any improvement in disease-free survival, the benefits of total skin Electron Therapy for symptom palliation should be considered. Pediatr Blood Cancer 2008;50:1054–1055. © 2007 Wiley-Liss, Inc.