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Rühm W, Pihet P, Schuhmacher H. The European Radiation Dosimetry Group-a 40 year success story. RADIATION PROTECTION DOSIMETRY 2023; 199:1659-1669. [PMID: 37819296 DOI: 10.1093/rpd/ncac193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 08/08/2022] [Accepted: 09/02/2022] [Indexed: 10/13/2023]
Abstract
The European Radiation Dosimetry Group (EURADOS) was founded in 1982. Since then, the group has continuously developed and is currently a network of 80 institutions and more than 600 individual scientists across Europe, including exchange with the scientific community outside of Europe. EURADOS supports research and development of dosimetry and harmonising dosimetric practices. This paper describes the major milestones in the history of the organization. It starts from the very beginning when the idea was born and describes periods during which the role and strategy of the network had to be defined, elaborated and refined. Finally, it ends to date where EURADOS appears as an independent self-sustainable association, which is a reliable partner for various international organisations in radiation research and radiation protection. Major activities of EURADOS are highlighted such as (1) establishment and coordination of Working Groups, (2) regular organization of dosimetric intercomparisons for quality assurance of dosimetry procedures, (3) development and organization of education and training events, and (4) contributions towards the development of strategic and integrated radiation research in Europe.
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Affiliation(s)
- Werner Rühm
- Helmholtz Zentrum München, Institute of Radiation Medicine, Neuherberg 85764, Germany
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Sá AC, Barateiro A, Bednarz BP, Almeida P, Vaz P, Madaleno T. Comparison of 3DCRT and IMRT out-of-field doses in pediatric patients using Monte Carlo simulations with treatment planning system calculations and measurements. Front Oncol 2022; 12:879167. [PMID: 35992845 PMCID: PMC9388939 DOI: 10.3389/fonc.2022.879167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 07/04/2022] [Indexed: 11/13/2022] Open
Abstract
3DCRT and IMRT out-of-field doses in pediatric patients were compared using Monte Carlo simulations with treatment planning system calculations and measurements. Purpose Out-of-field doses are given to healthy tissues, which may allow the development of second tumors. The use of IMRT in pediatric patients has been discussed, as it leads to a "bath" of low doses to large volumes of out-of-field organs and tissues. This study aims to compare out-of-field doses in pediatric patients comparing IMRT and 3DCRT techniques using measurements, Monte Carlo (MC) simulations, and treatment planning system (TPS) calculations. Materials and methods A total dose of 54 Gy was prescribed to a PTV in the brain of a pediatric anthropomorphic phantom, for both techniques. To assess the out-of-field organ doses for both techniques, two treatment plans were performed with the 3DCRT and IMRT techniques in TPS. Measurements were carried out in a LINAC using a pediatric anthropomorphic phantom and thermoluminescent dosimeters to recreate the treatment plans, previously performed in the TPS. A computational model of a LINAC, the associated multileaf collimators, and a voxelized pediatric phantom implemented in the Monte Carlo N-Particle 6.1 computer program were also used to perform MC simulations of the out-of-field organ doses, for both techniques. Results The results obtained by measurements and MC simulations indicate a significant increase in dose using the IMRT technique when compared to the 3DCRT technique. More specifically, measurements show higher doses with IMRT, namely, in right eye (13,041 vs. 593 mGy), left eye (6,525 vs. 475 mGy), thyroid (79 vs. 70 mGy), right lung (37 vs. 28 mGy), left lung (27 vs. 20 mGy), and heart (31 vs. 25 mGy). The obtained results indicate that out-of-field doses can be seriously underestimated by TPS. Discussion This study presents, for the first time, out-of-field dose measurements in a realistic scenario and calculations for IMRT, centered on a voxelized pediatric phantom and an MC model of a medical LINAC, including MLC with log file-based simulations. The results pinpoint significant discrepancies in out-of-field doses for the two techniques and are a cause of concern because TPS calculations cannot accurately predict such doses. The obtained doses may presumably increase the risk of development of second tumors.
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Affiliation(s)
- Ana Cravo Sá
- Radiation Protection and Safety Group, Centro de Ciências e Tecnologias Nucleares (C2TN), Bobadela, Portugal
- Diagnostic, Therapeutic and Public Health Sciences Department, Escola Superior de Tecnologia da Saúde de Lisboa (ESTeSL), Lisbon, Portugal
- Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Andreia Barateiro
- Radiotherapy Department, Portuguese Institute of Oncology Francisco Gentil, Lisbon, Portugal
| | - Bryan P. Bednarz
- Department of Medical Physics, Wisconsin Institutes for Medical Research, University of Wisconsin Hospital and Clinics, Madison, WI, United States
| | - Pedro Almeida
- Instituto de Biofísica e Engenharia Biomédica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Pedro Vaz
- Radiation Protection and Safety Group, Centro de Ciências e Tecnologias Nucleares (C2TN), Bobadela, Portugal
| | - Tiago Madaleno
- Radiotherapy Department, Portuguese Institute of Oncology Francisco Gentil, Lisbon, Portugal
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Sohrabi M, Ebrahimzadeh Torkamani M, Ali Nedaie H. Whole-body photoneutron 360° angular distribution dosimetry by novel "Sohrabi neutron dosimetry methods". Phys Med 2022; 95:167-175. [PMID: 35183907 DOI: 10.1016/j.ejmp.2022.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 01/24/2022] [Accepted: 02/01/2022] [Indexed: 11/28/2022] Open
Abstract
PURPOSE Whole-body photoneutron (PN) energy-specific dosimetry on phantom surfaces and 360°angular fast PN distribution dosimetry on and around polyethylene (PE) phantom organs for prostate cancer in 10 cm × 10 cm and 20 cm × 20 cm field sizes of 18 MV X-rays of Varian Clinac 2100C linear accelerator. METHODS Novel "Sohrabi neutron dosimetry methods" including "miniature passive neutron dosimeter/spectrometer" and "strip polycarbonate neutron dosimeters" were applied. Energy-specific PN dose equivalents on surface as well as 360°fast PN dose equivalent angular distributions on and around PE phantom organs; head, neck, thorax, arms, pelvis, thighs and legs were determined. RESULTS Matrix of surface (skin) energy-specific PN dose equivalents including total thermal, total epithermal, total fast, sum total thermal + epithermal and sum total thermal + epithermal + fast, and 360°angular fast PN dose equivalent responses were determined. The results indicate that data matrix of 20 cm × 20 cm field size provides higher PN dose equivalent values than those of 10 cm × 10 cm field size for surface points even remote from the central axis and for all 360°angular fast PN dose equivalent distributions on organs studied. CONCLUSIONS Matrix of energy-specific PN dose equivalents was obtained demonstrating that the Sohrabi neutron dosimetry methods applied are unique for energy-specific PN dose equivalent studies as well as for 360°angular PN dose equivalent distribution data for PN-SPC risk estimation. The dosimetry methods can be specifically applied to many other exotic applications in health physics, medical physics, space flight dosimetry, and nuclear science and technology.
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Affiliation(s)
- Mehdi Sohrabi
- Health Physics and Dosimetry Research Laboratory, Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran.
| | - Morteza Ebrahimzadeh Torkamani
- Health Physics and Dosimetry Research Laboratory, Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran
| | - Hassan Ali Nedaie
- Department of Radiotherapy Oncology, Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran
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Xu HB, Dong AD, Liu MT, Tseng HC, Chen CY, Tsai SY. Evaluating photoneutron dose equivalents for lung cancer using PMMA phantoms undergoing 15 MV IMRT. Technol Health Care 2022; 30:37-46. [PMID: 35124582 PMCID: PMC9028617 DOI: 10.3233/thc-228004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND: According to statistics of the Ministry of Health and Welfare in 2017, the second leading cause of death in Taiwan was lung cancer. OBJECTIVE: Routine treatment planning does not consider photoneutron dose equivalent (PNDE) of patient induced secondary radiation resulting from primary exposure of lung cancer. However, such treatment is potentially important for improving estimates of health risks. METHODS: This study used 10, 30, 50, 70, and 90 kg of polymethylmethacrylate (PMMA) phantoms as patient to measure PNDE varying anatomical area during lung cancer of intensity modulated radiotherapy (IMRT) treatment. Paired thermoluminescent dosimeters (TLD-600 and 700) were calibrated using university reactor neutrons. TLDs were inserted into phantom which was closely corresponded of the represented tissues or organs. RESULTS: Neutron doses (ND) of organ or tissue (NDT) were determined in these phantoms using paired TLDs approach. The risks of incurring fatal secondary malignancies, maximum statistical and total errors were estimated. Evaluated PNDE ranged from 0.80 ± 0.12 to 0.56 ± 0.08 mSv/Gy for these phantoms. CONCLUSION: The estimated NDT decreased with increasing distance that is from the central axis. Evaluated PNDE and ND𝑠𝑘𝑖𝑛 for these phantoms were discussed. This investigation also identified secondary risks associated with PNDE relating to radiation protection.
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Affiliation(s)
- Hai-Bing Xu
- Department of Medical Imaging, Jiangsu Vocational College of Medicine, Yancheng, Jiangsu, China
| | - An-Ding Dong
- Department of Medical Imaging, Jiangsu Vocational College of Medicine, Yancheng, Jiangsu, China
| | - Mu-Tai Liu
- Department of Radiation Oncology, Changhua Christian Hospital, Changhua, Taiwan
| | - Hsien-Chun Tseng
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Chung Shan Medical University, Taichung, Zhejiang, China
- School of Medicine, Chung Shan Medical University, Taichung, Zhejiang, China
| | - Chien-Yi Chen
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Chung Shan Medical University, Taichung, Zhejiang, China
- Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Zhejiang, China
- Department of Medical Imaging, Jiangsu Vocational College of Medicine, Yancheng, Jiangsu, China
| | - Sung-Yi Tsai
- Department of Medical Imaging, Jiangsu Vocational College of Medicine, Yancheng, Jiangsu, China
- Department of Medical Imaging, Jiangsu Vocational College of Medicine, Yancheng, Jiangsu, China
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Sohrabi M, Torkamani ME. Breakthrough whole body energy-specific and tissue-specific photoneutron dosimetry by novel miniature neutron dosimeter/spectrometer. Sci Rep 2021; 11:20552. [PMID: 34654858 PMCID: PMC8519960 DOI: 10.1038/s41598-021-99612-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 09/28/2021] [Indexed: 11/09/2022] Open
Abstract
Breakthrough whole body energy-specific photoneutron (PN) dosimetry was made in/out-of-field in polyethylene phantom organ surface/depths remote from isocenter of 10 × 10 cm2 field prostate cancer therapy in 18 MV X-rays Varian Clinac 2100C medical linear accelerator for PN tissue-specific second primary cancer (PN-SPC) risk estimation. A novel miniature neutron dosimeter/spectrometer with polycarbonate/10B/cadmium inserts was invented and applied. Each dosimeter determines seven tissue-specific dose equivalent (mSv)/Gy X-ray dose at each measurement point providing seven major energy-specific responses for beam thermal, albedo thermal, total thermal, total epithermal, total fast, sum of totals (thermal + epithermal) and sum of totals (thermal + epithermal + fast) PNs dose equivalents. The neutron dosimeter is simple, efficient, and unique with high spatial resolution and provides matrix of energy-specific PN dose equivalent (mSv)/Gy X-ray dose on surface and organ depths for tissue-specific PN-SPC risk estimation. The dosimeter also performs like a "miniature neutron spectrometer" and is unique for other applications in health physics in particular individual neutron dosimetry, medical physics, space flights, science and technology.
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Affiliation(s)
- Mehdi Sohrabi
- Health Physics and Dosimetry Research Laboratory, Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran.
| | - Morteza Ebrahimzadeh Torkamani
- Health Physics and Dosimetry Research Laboratory, Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran
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Veiga C, Lim P, Anaya VM, Chandy E, Ahmad R, D'Souza D, Gaze M, Moinuddin S, Gains J. Atlas construction and spatial normalisation to facilitate radiation-induced late effects research in childhood cancer. Phys Med Biol 2021; 66. [PMID: 33735848 PMCID: PMC8112163 DOI: 10.1088/1361-6560/abf010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/18/2021] [Indexed: 11/12/2022]
Abstract
Reducing radiation-induced side effects is one of the most important challenges in paediatric cancer treatment. Recently, there has been growing interest in using spatial normalisation to enable voxel-based analysis of radiation-induced toxicities in a variety of patient groups. The need to consider three-dimensional distribution of doses, rather than dose-volume histograms, is desirable but not yet explored in paediatric populations. In this paper, we investigate the feasibility of atlas construction and spatial normalisation in paediatric radiotherapy. We used planning computed tomography (CT) scans from twenty paediatric patients historically treated with craniospinal irradiation to generate a template CT that is suitable for spatial normalisation. This childhood cancer population representative template was constructed using groupwise image registration. An independent set of 53 subjects from a variety of childhood malignancies was then used to assess the quality of the propagation of new subjects to this common reference space using deformable image registration (i.e. spatial normalisation). The method was evaluated in terms of overall image similarity metrics, contour similarity and preservation of dose-volume properties. After spatial normalisation, we report a dice similarity coefficient of 0.95 ± 0.05, 0.85 ± 0.04, 0.96 ± 0.01, 0.91 ± 0.03, 0.83 ± 0.06 and 0.65 ± 0.16 for brain and spinal canal, ocular globes, lungs, liver, kidneys and bladder. We then demonstrated the potential advantages of an atlas-based approach to study the risk of second malignant neoplasms after radiotherapy. Our findings indicate satisfactory mapping between a heterogeneous group of patients and the template CT. The poorest performance was for organs in the abdominal and pelvic region, likely due to respiratory and physiological motion and to the highly deformable nature of abdominal organs. More specialised algorithms should be explored in the future to improve mapping in these regions. This study is the first step toward voxel-based analysis in radiation-induced toxicities following paediatric radiotherapy.
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Affiliation(s)
- Catarina Veiga
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Pei Lim
- Department of Oncology, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Virginia Marin Anaya
- Radiotherapy Physics Services, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Edward Chandy
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.,UCL Cancer Institute, University College London, London, United Kingdom
| | - Reem Ahmad
- Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Derek D'Souza
- Radiotherapy Physics Services, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Mark Gaze
- Department of Oncology, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Syed Moinuddin
- Radiotherapy, University College London Hospital NHS Foundation Trust, London, United Kingdom
| | - Jennifer Gains
- Department of Oncology, University College London Hospital NHS Foundation Trust, London, United Kingdom
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Faghihi Moghaddam F, Bakhshandeh M, Ghorbani M, Mofid B. Assessing the out-of-field dose calculation accuracy by eclipse treatment planning system in sliding window IMRT of prostate cancer patients. Comput Biol Med 2020; 127:104052. [PMID: 33126124 DOI: 10.1016/j.compbiomed.2020.104052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/07/2020] [Accepted: 10/09/2020] [Indexed: 11/18/2022]
Abstract
AIM The objective of this study was to evaluate out-of-field dose distribution calculation accuracy by the Anisotropic Analytical Algorithm (AAA), version 13.0.26, in Eclipse TPS, (Varian Medical Systems, Palo Alto, Ca, USA) for sliding window IMRT delivery technique in prostate cancer patients. MATERIALS AND METHODS Prostate IMRT plans with nine coplanar were calculated with the AAA Eclipse treatment planning system. To assess the accuracy of dose calculation predicted by the Eclipse in normal tissue and OARs located out of radiation field areas, including the rectum, bladder, right and left head of the femur, absolute organ dose value, and dose distribution were measured using the Delta4+ IMRT phantom. RESULTS In the out-of-field areas, underestimation of -0.66% in organs near the field edge to -39.63% in organs far from the field edge (2.5 and 7.3 cm respectively) occurred in the TPS calculations. The percentage of dose deviation for the femoral heads was 95.7 on average while for the organ closer to the target (rectum) it was 79.81. CONCLUSIONS AAA dosimetry algorithm (used in Eclipse TPS) showed poor dose calculation in areas beyond the treatment fields border where underestimation varies with the distance from the field edges. A significant underestimation was found for the AAA algorithm in the sliding window IMRT technique (P-value > 0.05).
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Affiliation(s)
- Fahimeh Faghihi Moghaddam
- Biomedical Engineering and Medical Physics Department, Faculty of Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Mohsen Bakhshandeh
- Department of Radiation Technology, Faculty of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Mahdi Ghorbani
- Department of Medical Physics, Faculty of Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Bahram Mofid
- Department of Radiation Oncology, Faculty of Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Dosimetric measurement of testicular dose for colorectal cancer using optically-stimulated luminescent dosimeters in radiotherapy. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.108792] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Ghareeb F, Esposito A, Lencart J, Santos JA. Localized extra focal dose collimator angle dependence during VMAT: An out-of-field Monte Carlo study using PRIMO software. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.108694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Assessment of out-of-field doses in radiotherapy treatments of paediatric patients using Monte Carlo methods and measurements. Phys Med 2020; 71:53-61. [DOI: 10.1016/j.ejmp.2020.02.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 12/18/2019] [Accepted: 02/13/2020] [Indexed: 01/22/2023] Open
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Irazola L, Sánchez-Nieto B, García-Hernández MT, Terrón JA, Roselló J, Ortiz-Seidel M, Béjar MJ, Linares R, Vélazquez S, Sánchez-Doblado F. 10-MV SBRT FFF IRRADIATION TECHNIQUE IS ASSOCIATED TO THE LOWEST PERIPHERAL DOSE: THE OUTCOME OF 142 TREATMENT PLANS FOR THE 10 MOST COMMON TUMOUR LOCATIONS. RADIATION PROTECTION DOSIMETRY 2019; 185:183-195. [PMID: 30649534 DOI: 10.1093/rpd/ncy292] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 12/06/2018] [Accepted: 12/30/2018] [Indexed: 06/09/2023]
Abstract
There is a growing interest in the combined use of Stereotactic Body Radiation Therapy (SBRT) with Flattening Filter Free (FFF) due to the high local control rates and reduced treatment times, compared to conventionally fractionated treatments. It has been suggested that they may also provide a better radiation protection to radiotherapy patients as a consequence of the expected decrease in peripheral doses. This work aims to determine this reduction in unattended out-of-field regions, where no CT information is available but an important percentage of second primary cancers occur. For that purpose, ten different cases suitable for SBRT were chosen. Thus, 142 different treatment plans including SBRT, as well as 3D-CRT, IMRT and VMAT (with standard fractionation) in low and high energies for Varian (FF and FFF), Siemens and Elekta machines were created. Then, photon and neutron peripheral dose in 14 organs were assessed and compared using two analytical models. For the prostate case, uncomplicated and cancer free control probability estimation was also carried out. As a general behavior, SBRT plans led to the lowest peripheral doses followed by 3D-CRT, VMAT and IMRT, in this order. Unflattened beams proved to be the most effective in reducing peripheral doses, especially for 10 MV. The obtained results suggest that FFF beams for SBRT with 10 MV represent the best compromise between dose delivery efficiency and peripheral dose reduction.
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Affiliation(s)
- L Irazola
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Sevilla, Spain
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain
| | - B Sánchez-Nieto
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | - J A Terrón
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Sevilla, Spain
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain
| | - J Roselló
- Servicio de Radiofísica ERESA, Hospital General Universitario, Valencia, Spain
| | - M Ortiz-Seidel
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Sevilla, Spain
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain
| | - M J Béjar
- Servicio de Radiofísica, Hospital Universitario Ramón y Cajal, Madrid, Spain
| | - R Linares
- Servicio de Radiofísica, Hospital Infanta Luisa, Sevilla, Spain
| | - S Vélazquez
- Servicio de Radiofísica, Hospital Universitario Virgen del Rocío, Sevilla Spain
| | - F Sánchez-Doblado
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Sevilla, Spain
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain
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Colnot J, Barraux V, Loiseau C, Berejny P, Batalla A, Gschwind R, Huet C. 14 Healthy tissue doses in a pulmonary stereotactic treatment using the Cyberknife: Application of two dosimetric methods. Phys Med 2019. [DOI: 10.1016/j.ejmp.2019.09.095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Ghareeb F, Lencart J, Oliveira J, Santos JAM. Characterization of Extrafocal Dose Influence on the Out-of-Field Dose Distribution by Monte Carlo Simulations and Dose Measurements. HEALTH PHYSICS 2019; 117:489-503. [PMID: 31033708 DOI: 10.1097/hp.0000000000001079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Out-of-field scattered and transmitted extrafocal radiation may induce secondary cancer in long-term survivors of external radiotherapy. Pediatric patients have higher life expectancy and tend to receive higher secondary radiation damage due to geometric and biological factors. The goal of this study is to characterize the location and the magnitude of extrafocal dose regions in the case of three-dimensional conformal radiotherapy and volumetric arc therapy, to apply this information to clinical treatment cases, and to provide mitigation strategies. Extrafocal dose has been investigated in a Varian TrueBeam linac equipped with a high-definition 120 multileaf collimator using different physical and virtual phantoms, dose calculation (including Monte Carlo techniques), and dose measurement methods. All Monte Carlo calculations showed excellent agreement with measurements. Treatment planning system calculations failed to provide reliable results out of the treatment field. Both Monte Carlo calculations and dose measurements showed regions with higher dose (extrafocal dose areas) when compared to the background. These areas start to be noticeable beyond 11 cm from the isocenter in the direction perpendicular to the multileaf collimator leaves' travel direction. Out-of-field extrafocal doses up to 160% of the mean dose transmitted through the closed multileaf collimator were registered. Two overlapping components were observed in the extrafocal distribution: the first is an almost elliptical blurred dose distribution, and the second is a well-defined rectangular dose distribution. Extra precautions should be taken into consideration when treating pediatric patients with a high-definition 120 multileaf collimator to avoid directing the extrafocal radiation into a radiosensitive organ during external beam therapy.
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Affiliation(s)
- Firass Ghareeb
- Medical Physics, Radiobiology and Radiation Protection Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
| | - Joana Lencart
- Medical Physics, Radiobiology and Radiation Protection Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
- Medical Physics Department, Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
| | - Jorge Oliveira
- Medical Physics, Radiobiology and Radiation Protection Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
| | - João A M Santos
- Medical Physics, Radiobiology and Radiation Protection Group, IPO Porto Research Center (CI-IPOP), Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
- Medical Physics Department, Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal
- Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, Porto, Portugal
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Schneider CW, Newhauser WD, Wilson LJ, Kapsch RP. A physics-based analytical model of absorbed dose from primary, leakage, and scattered photons from megavoltage radiotherapy with MLCs. ACTA ACUST UNITED AC 2019; 64:185017. [DOI: 10.1088/1361-6560/ab303a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Alves JG, Fantuzzi E, Rühm W, Gilvin P, Vargas A, Tanner R, Rabus H, Lopez MA, Breustedt B, Harrison R, Stolarczyk L, Fattibene P, Woda C, Caresana M, Knežević Ž, Bottollier-Depois JF, Clairand I, Mayer S, Miljanic S, Olko P, Schuhmacher H, Stadtmann H, Vanhavere F. EURADOS education and training activities. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:R37-R50. [PMID: 31307030 DOI: 10.1088/1361-6498/ab3256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This paper provides a summary of the Education and Training (E&T) activities that have been developed and organised by the European Radiation Dosimetry Group (EURADOS) in recent years and in the case of Training Courses over the last decade. These E&T actions include short duration Training Courses on well-established topics organised within the activity of EURADOS Working Groups (WGs), or one-day events integrated in the EURADOS Annual Meeting (workshops, winter schools, the intercomparison participants' sessions and the learning network, among others). Moreover, EURADOS has recently established a Young Scientist Grant and a Young Scientist Award. The Grant supports young scientists by encouraging them to perform research projects at other laboratories of the EURADOS network. The Award is given in recognition of excellent work developed within the WGs' work programme. Additionally, EURADOS supports the dissemination of knowledge in radiation dosimetry by promoting and endorsing conferences such as the individual monitoring (IM) series, the neutron and ion dosimetry symposia (NEUDOS) and contributions to E&T sessions at specific events.
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Affiliation(s)
- J G Alves
- EURADOS, EURADOS e.V. Postfach 1129, D-85758 Neuherberg, Germany. Universidade de Lisboa (UL), Instituto Superior Técnico (IST), Laboratório de Proteção e Segurança Radiológica (LPSR), Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal. Departamento de Engenharia e Ciências Nucleares (DECN), Centro de Ciências e Tecnologias Nucleares (C2TN), do IST, Portugal
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Sánchez-Nieto B, Romero-Expósito M, Terrón JA, Irazola L, Paiusco M, Cagni E, Ghetti C, Filice S, Sánchez-Doblado F. Intensity-modulated radiation therapy and volumetric modulated arc therapy versus conventional conformal techniques at high energy: Dose assessment and impact on second primary cancer in the out-of-field region. Rep Pract Oncol Radiother 2018; 23:251-259. [PMID: 29991929 PMCID: PMC6035902 DOI: 10.1016/j.rpor.2018.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Revised: 01/19/2018] [Accepted: 04/12/2018] [Indexed: 12/22/2022] Open
Abstract
The aim of this work was to estimate peripheral neutron and photon doses associated with the conventional 3D conformal radiotherapy techniques in comparison to modern ones such as Intensity modulated radiation therapy and volumetric modulated arc therapy. Assessment in terms of second cancer incidence ought to peripheral doses was also considered. For that, a dosimetric methodology proposed by the authors has been applied beyond the region where there is no CT information and, thus, treatment planning systems do not calculate and where, nonetheless, about one third of second primary cancers occurs.
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Affiliation(s)
- Beatriz Sánchez-Nieto
- Instituto de Física, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center UC Investigation in Oncology at Pontificia Universidad Católica de Chile, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | - José Antonio Terrón
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain
| | - Leticia Irazola
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Sevilla, Spain
| | - Marta Paiusco
- Veneto Institute of Oncology IOV – IRCCS, Padua, Italy
| | | | - Caterina Ghetti
- Servizio di Fisica Sanitaria, Azienda Ospedaliera Universitaria di Parma, Italy
| | - Silvano Filice
- Servizio di Fisica Sanitaria, Azienda Ospedaliera Universitaria di Parma, Italy
| | - Francisco Sánchez-Doblado
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Sevilla, Spain
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Majer M, Stolarczyk L, De Saint-Hubert M, Kabat D, Kneževic Ž, Miljanic S, Mojzeszek N, Harrison R. OUT-OF-FIELD DOSE MEASUREMENTS FOR 3D CONFORMAL AND INTENSITY MODULATED RADIOTHERAPY OF A PAEDIATRIC BRAIN TUMOUR. RADIATION PROTECTION DOSIMETRY 2017; 176:331-340. [PMID: 28338841 DOI: 10.1093/rpd/ncx015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/29/2017] [Indexed: 05/03/2023]
Abstract
The purpose of this study was to measure out-of-field organ doses in clinical conditions in anthropomorphic paediatric phantoms which received a simulated treatment of a brain tumour with intensity modulated radiotherapy (IMRT) and 3D conformal radiotherapy (3D CRT). Organ doses measured with radiophotoluminescent and thermoluminescent dosemeters were on average 1.6 and 3.0 times higher for the 5 y-old than for the 10 y-old phantom for IMRT and 3D CRT, respectively. A larger 5-y to 10-y organ dose ratio for 3D CRT can be explained because the use of a mechanical wedge for the 5-y-old 3D CRT phantom treatment increased out-of-field doses. Due to different configurations of the radiation fields, for both phantoms, the IMRT technique resulted in a higher non-target brain dose and higher eye doses but lower thyroid doses compared to 3D CRT. For 3D CRT (which used a non-coplanar field configuration), eye doses were 3-6% and for IMRT (which used a coplanar field configuration) 27-30% of the treatment dose, respectively. For thyroid and more distant organs, doses were less than 1% of the treatment dose. Comparison of measured doses and doses calculated by the treatment planning system (TPS) showed that the TPS underestimated out-of-field doses both for IMRT and 3D CRT.
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Affiliation(s)
- Marija Majer
- Ruder Boškovic Institute, Bijenicka cesta 54, 10000 Zagreb, Croatia
| | - Liliana Stolarczyk
- Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Krakow, Poland
| | | | - Damian Kabat
- Centre of Oncology M. Sklodowska-Curie Memorial Institute, Garncarska 11, 31-115 Krakow, Poland
| | - Željka Kneževic
- Ruder Boškovic Institute, Bijenicka cesta 54, 10000 Zagreb, Croatia
| | - Saveta Miljanic
- Ruder Boškovic Institute, Bijenicka cesta 54, 10000 Zagreb, Croatia
| | - Natalia Mojzeszek
- Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Krakow, Poland
| | - Roger Harrison
- University of Newcastle, Faculty of Medical Sciences, Newcastle upon Tyne NE2 4HH, UK
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Majer M, Knežević Ž, Liu H, Hršak H, Miljanić S, Zhuo W, Heinrich Z. Paediatric organ doses from CT-simulation in brain tumour GK radiosurgery treatment – Phantom study. RADIAT MEAS 2017. [DOI: 10.1016/j.radmeas.2017.03.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Mukherjee B, Fuentes C, Lambert J. Out-of-field dosimetry and 2nd cancer risk assessment of child patients under proton therapy using a TLD-based microdosimeter. RADIAT MEAS 2017. [DOI: 10.1016/j.radmeas.2017.04.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Schneider CW, Newhauser WD, Wilson LJ, Schneider U, Kaderka R, Miljanić S, Knežević Ž, Stolarcyzk L, Durante M, Harrison RM. A descriptive and broadly applicable model of therapeutic and stray absorbed dose from 6 to 25 MV photon beams. Med Phys 2017; 44:3805-3814. [PMID: 28429827 DOI: 10.1002/mp.12286] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 02/09/2017] [Accepted: 03/23/2017] [Indexed: 01/01/2023] Open
Abstract
PURPOSE To develop a simple model of therapeutic and stray absorbed dose for a variety of treatment machines and techniques without relying on proprietary machine-specific parameters. METHODS Dosimetry measurements conducted in this study and from the literature were used to develop an analytical model of absorbed dose from a variety of treatment machines and techniques in the 6 to 25 MV interval. A modified one-dimensional gamma-index analysis was performed to evaluate dosimetric accuracy of the model on an independent dataset consisting of measured dose profiles from seven treatment units spanning four manufacturers. RESULTS The average difference between the calculated and measured absorbed dose values was 9.9% for those datasets on which the model was trained. Additionally, these results indicate that the model can provide accurate calculations of both therapeutic and stray radiation dose from a wide variety of radiotherapy units and techniques. CONCLUSIONS We have developed a simple analytical model of absorbed dose from external beam radiotherapy treatments in the 6 to 25 MV beam energy range. The model has been tested on measured data from multiple treatment machines and techniques, and is broadly applicable to contemporary external beam radiation therapy.
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Affiliation(s)
- Christopher W Schneider
- Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA, 70803-4001, USA
| | - Wayne D Newhauser
- Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA, 70803-4001, USA.,Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA, 70809, USA
| | - Lydia J Wilson
- Department of Physics and Astronomy, Louisiana State University and Agricultural and Mechanical College, Baton Rouge, LA, 70803-4001, USA
| | - Uwe Schneider
- Faculty of Science, University of Zürich, Winterthurerstrasse 260, 8057, Zürich, Switzerland.,Institute for Radiotherapy, Hirslanden Medical Center, Rain 34, 5000, Aarau, Switzerland
| | - Robert Kaderka
- GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, 64291, Germany
| | - Saveta Miljanić
- Ruder Bošković Institute, Radiation Chemistry and Dosimetry Laboratory, Bijenićka 54, HR-10000, Zagreb, Croatia
| | - Željka Knežević
- Ruder Bošković Institute, Radiation Chemistry and Dosimetry Laboratory, Bijenićka 54, HR-10000, Zagreb, Croatia
| | - Liliana Stolarcyzk
- Bronowice Cyclotron Centre, Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342, Krakow, Poland
| | - Marco Durante
- Trento Institute for Fundamental Physics and Applications (TIFPA), National Institute of Nuclear Physics (INFN), University of Trento, Via Sommarive 14, 38123 Povo, Trento, Italy
| | - Roger M Harrison
- Faculty of Medical Sciences, University of Newcastle, Newcastle-upon-Tyne, NE2 4HH, UK
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Newhauser WD, de Gonzalez AB, Schulte R, Lee C. A Review of Radiotherapy-Induced Late Effects Research after Advanced Technology Treatments. Front Oncol 2016; 6:13. [PMID: 26904500 PMCID: PMC4748041 DOI: 10.3389/fonc.2016.00013] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Accepted: 01/12/2016] [Indexed: 01/01/2023] Open
Abstract
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.
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Affiliation(s)
- Wayne D. Newhauser
- Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, USA
- Department of Physics, Mary Bird Perkins Cancer Center, Baton Rouge, LA, USA
| | | | - Reinhard Schulte
- Department of Basic Sciences, Loma Linda University Medical Center, Loma Linda, CA, USA
| | - Choonsik Lee
- Radiation Epidemiology Branch, National Institutes of Health, Rockville, MD, USA
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Rühm W, Fantuzzi E, Harrison R, Schuhmacher H, Vanhavere F, Alves J, Bottollier Depois JF, Fattibene P, Knežević Ž, Lopez MA, Mayer S, Miljanić S, Neumaier S, Olko P, Stadtmann H, Tanner R, Woda C. EURADOS strategic research agenda: vision for dosimetry of ionising radiation. RADIATION PROTECTION DOSIMETRY 2016; 168:223-34. [PMID: 25752758 PMCID: PMC4884873 DOI: 10.1093/rpd/ncv018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/05/2015] [Accepted: 02/06/2015] [Indexed: 05/04/2023]
Abstract
Since autumn 2012, the European Radiation Dosimetry Group (EURADOS) has been developing its Strategic Research Agenda (SRA), which is intended to contribute to the identification of future research needs in radiation dosimetry in Europe. The present article summarises-based on input from EURADOS Working Groups (WGs) and Voting Members-five visions in dosimetry and defines key issues in dosimetry research that are considered important for the next decades. The five visions include scientific developments required towards (a) updated fundamental dose concepts and quantities, (b) improved radiation risk estimates deduced from epidemiological cohorts, (c) efficient dose assessment for radiological emergencies, (d) integrated personalised dosimetry in medical applications and (e) improved radiation protection of workers and the public. The SRA of EURADOS will be used as a guideline for future activities of the EURADOS WGs. A detailed version of the SRA can be downloaded as a EURADOS report from the EURADOS website (www.eurados.org).
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Affiliation(s)
- W Rühm
- Helmholtz Center Munich, Institute of Radiation Protection, Neuherberg, Germany
| | - E Fantuzzi
- Radiation Protection Institute, ENEA, Bologna, Italy
| | | | - H Schuhmacher
- Physikalisch Technische Bundesanstalt (PTB), Braunschweig, Germany
| | - F Vanhavere
- Belgian Nuclear Research Centre (SCK-CEN), Mol, Belgium
| | - J Alves
- Instituto Superior Técnico (IST), CTN, Lisboa, Portugal
| | - J F Bottollier Depois
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay-aux-Roses Cedex, France
| | - P Fattibene
- Istituto Superiore di Sanità (ISS), Rome, Italy
| | - Ž Knežević
- Ruđer Bošković Institute (RBI), Zagreb, Croatia
| | - M A Lopez
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
| | - S Mayer
- Paul Scherer Institut (PSI), Villigen, Switzerland
| | - S Miljanić
- Ruđer Bošković Institute (RBI), Zagreb, Croatia
| | - S Neumaier
- Physikalisch Technische Bundesanstalt (PTB), Braunschweig, Germany
| | - P Olko
- Instytut Fizyki Jądrowej (IFJ), Krakow, Poland
| | - H Stadtmann
- Seibersdorf Labor GmbH, Seibersdorf, Austria
| | - R Tanner
- Public Health England, Chilton, Didcot, UK
| | - C Woda
- Helmholtz Center Munich, Institute of Radiation Protection, Neuherberg, Germany
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Miljanić S, Bordy JM, d'Errico F, Harrison R, Olko P. Out-of-field dose measurements in radiotherapy – An overview of activity of EURADOS Working Group 9: Radiation protection in medicine. RADIAT MEAS 2014. [DOI: 10.1016/j.radmeas.2014.04.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Matsushima LC, Veneziani GR, Sakuraba RK, Cruz JC, Campos LL. Determination of the radiation dose scattered outside the target volume treated with IMRT technique. RADIAT MEAS 2014. [DOI: 10.1016/j.radmeas.2014.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Radiotherapy out-of-field dosimetry: Experimental and computational results for photons in a water tank. RADIAT MEAS 2013. [DOI: 10.1016/j.radmeas.2013.06.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Di Fulvio A, Tana L, Caresana M, D'Agostino E, de San Pedro M, Domingo C, d'Errico F. Clinical simulations of prostate radiotherapy using BOMAB-like phantoms: Results for neutrons. RADIAT MEAS 2013. [DOI: 10.1016/j.radmeas.2013.06.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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