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Romero-Expósito M, Liszka M, Christou A, Toma-Dasu I, Dasu A. Range shifter contribution to neutron exposure of patients undergoing proton pencil beam scanning. Med Phys 2023. [PMID: 38112191 DOI: 10.1002/mp.16897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/30/2023] [Accepted: 12/03/2023] [Indexed: 12/21/2023] Open
Abstract
BACKGROUND Superficial targets require the use of the lowest energies within the available energy range in proton pencil-beam scanning (PBS) technique. However, the lower efficiency of the energy selection system at these energies and the requirement of a greater number of layers may represent disadvantages for this approach. The alternative is to use a range shifter (RS) at nozzle exit. However, one of the concerns of using this beamline element is that it becomes an additional source of neutrons that could irradiate organs situated far from the target. PURPOSE The purpose of this study is to assess the increase in neutron dose due to the RS in proton PBS technique. Additionally, an analytical model for the neutron production is tested. METHODS Two clinical plans, designed to achieve identical target coverage, were created for an anthropomorphic phantom. These plans consisted of a lateral field delivering an absorbed dose of 60 Gy (RBE) to the target. One of the plans employed the RS. The MCNP code was used to simulate the plans, evaluating the distribution of neutron dose equivalent (Hn ) and the equivalent dose in organ. In the plan with the RS plan, neutron production from both the patient and the RS were assessed separately. Hn values were also fitted versus the distance to field edge using a Gaussian function. RESULTS Hn per prescription dose, in the plan using the RS, ranged between 1.4 and 3.7 mSv/Gy at the field edge, whereas doses at 40 cm from the edge ranged from 9.9 to 32 μSv/Gy. These values are 1.2 to 10 times higher compared to those obtained without the RS. Both this factor and the contribution of neutrons originating from the RS increases with the distance from field edge. A triple-Gaussian function was able to reproduce the equivalent dose in organs within a factor of 2, although underestimating the values. CONCLUSIONS The dose deposited in the patient by the neutrons originating from the RS predominantly affects areas away from the target (beyond approximately 25 cm from field edge), resulting in a neutron dose equivalent of the order of mSv. This indicates an overall low neutron contribution from the use of RS in PBS.
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Affiliation(s)
- Maite Romero-Expósito
- The Skandion Clinic, Uppsala, Sweden
- Oncology Pathology Department, Karolinska Institutet, Solna, Sweden
| | | | | | - Iuliana Toma-Dasu
- Oncology Pathology Department, Karolinska Institutet, Solna, Sweden
- Medical Radiation Physics, Stockholm University, Stockholm, Sweden
| | - Alexandru Dasu
- The Skandion Clinic, Uppsala, Sweden
- Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
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Van Hoey O, Stolarczyk L, Lillhök J, Eliasson L, Mojzeszek N, Liszka M, Alkhiat A, Mares V, Trompier F, Trinkl S, Martínez-Rovira I, Romero-Expósito M, Domingo C, Ploc O, Harrison R, Olko P. Simulation and experimental verification of ambient neutron doses in a pencil beam scanning proton therapy room as a function of treatment plan parameters. Front Oncol 2022; 12:903537. [PMID: 36158693 PMCID: PMC9494550 DOI: 10.3389/fonc.2022.903537] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 07/07/2022] [Indexed: 11/23/2022] Open
Abstract
Out-of-field patient doses in proton therapy are dominated by neutrons. Currently, they are not taken into account by treatment planning systems. There is an increasing need to include out-of-field doses in the dose calculation, especially when treating children, pregnant patients, and patients with implants. In response to this demand, this work presents the first steps towards a tool for the prediction of out-of-field neutron doses in pencil beam scanning proton therapy facilities. As a first step, a general Monte Carlo radiation transport model for simulation of out-of-field neutron doses was set up and successfully verified by comparison of simulated and measured ambient neutron dose equivalent and neutron fluence energy spectra around a solid water phantom irradiated with a variation of different treatment plan parameters. Simulations with the verified model enabled a detailed study of the variation of the neutron ambient dose equivalent with field size, range, modulation width, use of a range shifter, and position inside the treatment room. For future work, it is planned to use this verified model to simulate out-of-field neutron doses inside the phantom and to verify the simulation results by comparison with previous in-phantom measurement campaigns. Eventually, these verified simulations will be used to build a library and a corresponding tool to allow assessment of out-of-field neutron doses at pencil beam scanning proton therapy facilities.
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Affiliation(s)
- Olivier Van Hoey
- Belgian Nuclear Research Center (SCK CEN), Institute for Environment, Health and Safety (EHS), Mol, Belgium
- *Correspondence: Olivier Van Hoey,
| | - Liliana Stolarczyk
- Danish Centre for Particle Therapy, Aarhus University Hospital (AUH), Aarhus, Denmark
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
- The Skandion Clinic, Uppsala, Sweden
| | - Jan Lillhök
- Swedish Radiation Safety Authority, Solna, Sweden
| | - Linda Eliasson
- Department of Physics, Royal Institute of Technology (KTH), Stockholm, Sweden
| | - Natalia Mojzeszek
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
| | - Malgorzata Liszka
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
- The Skandion Clinic, Uppsala, Sweden
| | - Ali Alkhiat
- The Skandion Clinic, Uppsala, Sweden
- Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Stockholm, Sweden
| | - Vladimir Mares
- Helmholtz Zentrum München, Institute of Radiation Medicine, Neuherberg, Germany
| | - François Trompier
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-Santé, Fontenay-aux-Roses, France
| | - Sebastian Trinkl
- Helmholtz Zentrum München, Institute of Radiation Medicine, Neuherberg, Germany
- Federal Office for Radiation Protection, Neuherberg, Germany
| | | | | | - Carles Domingo
- Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Ondrej Ploc
- Department of Radiation Dosimetry, Nuclear Physics Institute of the Czech Academy of Sciences (CAS), Prague, Czechia
| | - Roger Harrison
- Faculty of Medical Sciences, University of Newcastle upon Tyne, Newcastle Upon Tyne, United Kingdom
| | - Pawel Olko
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
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Knežević Ž, Stolarczyk L, Ambrožová I, Caballero-Pacheco MÁ, Davídková M, De Saint-Hubert M, Domingo C, Jeleń K, Kopeć R, Krzempek D, Majer M, Miljanić S, Mojżeszek N, Romero-Expósito M, Martínez-Rovira I, Harrison RM, Olko P. Out-of-Field Doses Produced by a Proton Scanning Beam Inside Pediatric Anthropomorphic Phantoms and Their Comparison With Different Photon Modalities. Front Oncol 2022; 12:904563. [PMID: 35957900 PMCID: PMC9361051 DOI: 10.3389/fonc.2022.904563] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/15/2022] [Indexed: 11/23/2022] Open
Abstract
Since 2010, EURADOS Working Group 9 (Radiation Dosimetry in Radiotherapy) has been involved in the investigation of secondary and scattered radiation doses in X-ray and proton therapy, especially in the case of pediatric patients. The main goal of this paper is to analyze and compare out-of-field neutron and non-neutron organ doses inside 5- and 10-year-old pediatric anthropomorphic phantoms for the treatment of a 5-cm-diameter brain tumor. Proton irradiations were carried out at the Cyclotron Centre Bronowice in IFJ PAN Krakow Poland using a pencil beam scanning technique (PBS) at a gantry with a dedicated scanning nozzle (IBA Proton Therapy System, Proteus 235). Thermoluminescent and radiophotoluminescent dosimeters were used for non-neutron dose measurements while secondary neutrons were measured with track-etched detectors. Out-of-field doses measured using intensity-modulated proton therapy (IMPT) were compared with previous measurements performed within a WG9 for three different photon radiotherapy techniques: 1) intensity-modulated radiation therapy (IMRT), 2) three-dimensional conformal radiation therapy (3D CDRT) performed on a Varian Clinac 2300 linear accelerator (LINAC) in the Centre of Oncology, Krakow, Poland, and 3) Gamma Knife surgery performed on the Leksell Gamma Knife (GK) at the University Hospital Centre Zagreb, Croatia. Phantoms and detectors used in experiments as well as the target location were the same for both photon and proton modalities. The total organ dose equivalent expressed as the sum of neutron and non-neutron components in IMPT was found to be significantly lower (two to three orders of magnitude) in comparison with the different photon radiotherapy techniques for the same delivered tumor dose. For IMPT, neutron doses are lower than non-neutron doses close to the target but become larger than non-neutron doses further away from the target. Results of WG9 studies have provided out-of-field dose levels required for an extensive set of radiotherapy techniques, including proton therapy, and involving a complete description of organ doses of pediatric patients. Such studies are needed for validating mathematical models and Monte Carlo simulation tools for out-of-field dosimetry which is essential for dedicated epidemiological studies which evaluate the risk of second cancers and other late effects for pediatric patients treated with radiotherapy.
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Affiliation(s)
- Željka Knežević
- Ruđer Bošković Institute, Zagreb, Croatia
- *Correspondence: Željka Knežević,
| | - Liliana Stolarczyk
- Danish Centre for Particle Therapy, Aarhus, Denmark
- Institute of Nuclear Physics, PAN, Krakow, Poland
| | - Iva Ambrožová
- Nuclear Physics Institute of the Czech Academy of Sciences, CAS, Řež, Czechia
| | | | - Marie Davídková
- Nuclear Physics Institute of the Czech Academy of Sciences, CAS, Řež, Czechia
| | | | | | - Kinga Jeleń
- Institute of Nuclear Physics, PAN, Krakow, Poland
- Tadeusz Kosciuszko Cracow University of Technology, Cracow, Poland
| | - Renata Kopeć
- Institute of Nuclear Physics, PAN, Krakow, Poland
| | | | | | | | | | - Maite Romero-Expósito
- Universitat Autònoma de Barcelona, Bellaterra, Spain
- Skandion Clinic, Uppsala, Sweden
| | | | - Roger M. Harrison
- University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom
| | - Paweł Olko
- Institute of Nuclear Physics, PAN, Krakow, Poland
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Mares V, Farah J, De Saint-Hubert M, Domański S, Domingo C, Dommert M, Kłodowska M, Krzempek K, Kuć M, Martínez-Rovira I, Michaś E, Mojżeszek N, Murawski Ł, Ploc O, Romero-Expósito M, Tisi M, Trompier F, Van Hoey O, Van Ryckeghem L, Wielunski M, Harrison RM, Stolarczyk L, Olko P. Neutron Radiation Dose Measurements in a Scanning Proton Therapy Room: Can Parents Remain Near Their Children During Treatment? Front Oncol 2022; 12:903706. [PMID: 35912238 PMCID: PMC9330633 DOI: 10.3389/fonc.2022.903706] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/16/2022] [Indexed: 11/15/2022] Open
Abstract
Purpose This study aims to characterize the neutron radiation field inside a scanning proton therapy treatment room including the impact of different pediatric patient sizes. Materials and Methods Working Group 9 of the European Radiation Dosimetry Group (EURADOS) has performed a comprehensive measurement campaign to measure neutron ambient dose equivalent, H*(10), at eight different positions around 1-, 5-, and 10-year-old pediatric anthropomorphic phantoms irradiated with a simulated brain tumor treatment. Several active detector systems were used. Results The neutron dose mapping within the gantry room showed that H*(10) values significantly decreased with distance and angular deviation with respect to the beam axis. A maximum value of about 19.5 µSv/Gy was measured along the beam axis at 1 m from the isocenter for a 10-year-old pediatric phantom at 270° gantry angle. A minimum value of 0.1 µSv/Gy was measured at a distance of 2.25 m perpendicular to the beam axis for a 1-year-old pediatric phantom at 140° gantry angle. The H*(10) dependence on the size of the pediatric patient was observed. At 270° gantry position, the measured neutron H*(10) values for the 10-year-old pediatric phantom were up to 20% higher than those measured for the 5-year-old and up to 410% higher than for the 1-year-old phantom, respectively. Conclusions Using active neutron detectors, secondary neutron mapping was performed to characterize the neutron field generated during proton therapy of pediatric patients. It is shown that the neutron ambient dose equivalent H*(10) significantly decreases with distance and angle with respect to the beam axis. It is reported that the total neutron exposure of a person staying at a position perpendicular to the beam axis at a distance greater than 2 m from the isocenter remains well below the dose limit of 1 mSv per year for the general public (recommended by the International Commission on Radiological Protection) during the entire treatment course with a target dose of up to 60 Gy. This comprehensive analysis is key for general neutron shielding issues, for example, the safe operation of anesthetic equipment. However, it also enables the evaluation of whether it is safe for parents to remain near their children during treatment to bring them comfort. Currently, radiation protection protocols prohibit the occupancy of the treatment room during beam delivery.
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Affiliation(s)
- Vladimir Mares
- Helmholtz Zentrum München, Institute of Radiation Medicine, Neuherberg, Germany
- *Correspondence: Vladimir Mares,
| | - Jad Farah
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-Santé, Fontenay-aux-Roses, France
| | - Marijke De Saint-Hubert
- Belgian Nuclear Research Center, (SCK CEN), Institute for Environment, Health and Safety (EHS), Mol, Belgium
| | - Szymon Domański
- National Centre for Nuclear Research, Radiological Metrology and Biomedical Physics Division, Otwock-Świerk, Poland
| | - Carles Domingo
- Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Martin Dommert
- Helmholtz Zentrum München, Institute of Radiation Medicine, Neuherberg, Germany
| | - Magdalena Kłodowska
- Cambridge University Hospital National Health Service (NHS) Trust, Medical Physics, Cambridge, United Kingdom
| | - Katarzyna Krzempek
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
| | - Michał Kuć
- National Centre for Nuclear Research, Radiological Metrology and Biomedical Physics Division, Otwock-Świerk, Poland
| | | | - Edyta Michaś
- National Centre for Nuclear Research, Radiological Metrology and Biomedical Physics Division, Otwock-Świerk, Poland
| | - Natalia Mojżeszek
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
| | - Łukasz Murawski
- National Centre for Nuclear Research, Radiological Metrology and Biomedical Physics Division, Otwock-Świerk, Poland
| | - Ondrej Ploc
- Department of Radiation Dosimetry, Nuclear Physics Institute of the Czech Academy of Sciences (CAS), Prague, Czechia
| | | | - Marco Tisi
- Helmholtz Zentrum München, Institute of Radiation Medicine, Neuherberg, Germany
| | - François Trompier
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-Santé, Fontenay-aux-Roses, France
| | - Olivier Van Hoey
- Belgian Nuclear Research Center, (SCK CEN), Institute for Environment, Health and Safety (EHS), Mol, Belgium
| | - Laurent Van Ryckeghem
- Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-Santé, Fontenay-aux-Roses, France
| | - Marek Wielunski
- Helmholtz Zentrum München, Institute of Radiation Medicine, Neuherberg, Germany
| | - Roger M. Harrison
- Faculty of Medical Sciences, University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom
| | - Liliana Stolarczyk
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
- Danish Centre for Particle Therapy, Aarhus University Hospital (AUH), Aarhus, Denmark
| | - Pawel Olko
- Institute of Nuclear Physics, Polish Academy of Sciences, (IFJ PAN), Krakow, Poland
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Domingo C, Lagares JI, Romero-Expósito M, Sánchez-Nieto B, Nieto-Camero JJ, Terrón JA, Irazola L, Dasu A, Sánchez-Doblado F. Peripheral Organ Equivalent Dose Estimation Procedure in Proton Therapy. Front Oncol 2022; 12:882476. [PMID: 35692801 PMCID: PMC9176390 DOI: 10.3389/fonc.2022.882476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/19/2022] [Indexed: 11/23/2022] Open
Abstract
The aim of this work is to present a reproducible methodology for the evaluation of total equivalent doses in organs during proton therapy facilities. The methodology is based on measuring the dose equivalent in representative locations inside an anthropomorphic phantom where photon and neutron dosimeters were inserted. The Monte Carlo simulation was needed for obtaining neutron energy distribution inside the phantom. The methodology was implemented for a head irradiation case in the passive proton beam of iThemba Labs (South Africa). Thermoluminescent dosimeter (TLD)-600 and TLD-700 pairs were used as dosimeters inside the phantom and GEANT code for simulations. In addition, Bonner sphere spectrometry was performed inside the treatment room to obtain the neutron spectra, some relevant neutron dosimetric quantities per treatment Gy, and a percentual distribution of neutron fluence and ambient dose equivalent in four energy groups, at two locations. The neutron spectrum at one of those locations was also simulated so that a reasonable agreement between simulation and measurement allowed a validation of the simulation. Results showed that the total out-of-field dose equivalent inside the phantom ranged from 1.4 to 0.28 mSv/Gy, mainly due to the neutron contribution and with a small contribution from photons, 10% on average. The order of magnitude of the equivalent dose in organs was similar, displaying a slow reduction in values as the organ is farther from the target volume. These values were in agreement with those found by other authors in other passive beam facilities under similar irradiation and measurement conditions.
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Affiliation(s)
- Carles Domingo
- Departament de Fisica, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Juan Ignacio Lagares
- Unidad de Aplicaciones Médicas, Departamento de Tecnología, Centro de Investigaciones Energéticas Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
| | | | | | | | - Jose Antonio Terrón
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla, Spain
| | - Leticia Irazola
- Servicio de Radiofísica y Protección Radiológica, Clínica Universidad de Navarra, Pamplona, Spain
| | - Alexandru Dasu
- The Skandion Clinic, Uppsala, Sweden.,Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
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Romero-Expósito M, Toma-Dasu I, Dasu A. Determining Out-of-Field Doses and Second Cancer Risk From Proton Therapy in Young Patients—An Overview. Front Oncol 2022; 12:892078. [PMID: 35712488 PMCID: PMC9197425 DOI: 10.3389/fonc.2022.892078] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
Proton therapy has the potential to provide survival and tumor control outcomes comparable and frequently superior to photon therapy. This has led to a significant concern in the medical physics community on the risk for the induction of second cancers in all patients and especially in younger patients, as they are considered more radiosensitive than adults and have an even longer expected lifetime after treatment. Thus, our purpose is to present an overview of the research carried out on the evaluation of out-of-field doses linked to second cancer induction and the prediction of this risk. Most investigations consisted of Monte Carlo simulations in passive beam facilities for clinical scenarios. These works established that equivalent doses in organs could be up to 200 mSv or 900 mSv for a brain or a craniospinal treatment, respectively. The major contribution to this dose comes from the secondary neutrons produced in the beam line elements. Few works focused on scanned-beam facilities, but available data show that, for these facilities, equivalent doses could be between 2 and 50 times lower. Patient age is a relevant factor in the dose level, especially for younger patients (by means of the size of the body) and, in addition, in the predicted risk by models (due to the age dependence of the radiosensitivity). For risks, the sex of the patient also plays an important role, as female patients show higher sensitivity to radiation. Thus, predicted risks of craniospinal irradiation can range from 8% for a 15-year-old male patient to 58% for a 2-year-old female patient, using a risk model from a radiological protection field. These values must be taken with caution due to uncertainties in risk models, and then dosimetric evaluation of stray radiation becomes mandatory in order to complement epidemiological studies and be able to model appropriate dose–response functions for this dose range. In this sense, analytical models represent a useful tool and some models have been implemented to be used for young patients. Research carried out so far confirmed that proton beam therapy reduces the out-of-field doses and second cancer risk. However, further investigations may be required in scanned-beam delivery systems.
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Affiliation(s)
- Maite Romero-Expósito
- The Skandion Clinic, Uppsala, Sweden
- Oncology Pathology Department, Karolinska Institutet, Stockholm, Sweden
- *Correspondence: Maite Romero-Expósito,
| | - Iuliana Toma-Dasu
- Oncology Pathology Department, Karolinska Institutet, Stockholm, Sweden
- Medical Radiation Physics, Stockholm University, Stockholm, Sweden
| | - Alexandru Dasu
- The Skandion Clinic, Uppsala, Sweden
- Medical Radiation Sciences, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
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García-Hernández T, Romero-Expósito M, Sánchez-Nieto B. Low dose radiation therapy for COVID-19: Effective dose and estimation of cancer risk. Radiother Oncol 2020; 153:289-295. [PMID: 33065184 PMCID: PMC7553901 DOI: 10.1016/j.radonc.2020.09.051] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 09/16/2020] [Accepted: 09/27/2020] [Indexed: 01/11/2023]
Abstract
BACKGROUND AND PURPOSE The objective of this work is to evaluate the risk of carcinogenesis of low dose ionizing radiation therapy (LDRT), for treatment of immune-related pneumonia following COVID-19 infection, through the estimation of effective dose and the lifetime attributable risk of cancer (LAR). MATERIAL AND METHODS LDRT treatment was planned in male and female computational phantoms. Equivalent doses in organs were estimated using both treatment planning system calculations and a peripheral dose model (based on ionization chamber measurements). Skin dose was estimated using radiochromic films. Later, effective dose and LAR were calculated following radiation protection procedures. RESULTS Equivalent doses to organs per unit of prescription dose range from 10 mSv/cGy to 0.0051 mSv/cGy. Effective doses range from 204 mSv to 426 mSv, for prescription doses ranging from 50 cGy to 100 cGy. Total LAR for a prescription dose of 50 cGy ranges from 1.7 to 0.29% for male and from 4.9 to 0.54% for female, for ages ranging from 20 to 80 years old. CONCLUSIONS The organs that mainly contribute to risk are lung and breast. Risk for out-of-field organs is low, less than 0.06 cases per 10000. Female LAR is on average 2.2 times that of a male of the same age. Effective doses are of the same order of magnitude as the higher-dose interventional radiology techniques. For a 60 year-old male, LAR is 8 times that from a cardiac CT, when prescription dose is 50 cGy.
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Affiliation(s)
| | - Maite Romero-Expósito
- Área de Ciencias Básicas y Ambientales, Instituto Tecnológico de Santo Domingo (INTEC), P.O. Box 342-9/249-2, Santo Domingo, Dominican Republic
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García-Hernández T, Vicedo-González A, Sánchez-Nieto B, Romero-Expósito M, Roselló-Ferrando J. PERIPHERAL SURFACE DOSE FROM A LINEAR ACCELERATOR: RADIOCHROMIC FILM EXPERIMENTAL MEASUREMENTS OF FLATTENING FILTER FREE VERSUS FLATTENED BEAMS. Radiat Prot Dosimetry 2020; 188:285-298. [PMID: 31922571 DOI: 10.1093/rpd/ncz286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/06/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
There is a growing interest in the use of flattening filter free (FFF) beams due to the shorter treatment times. The reduction of head scatter suggests a better radiation protection to radiotherapy patients, considering the expected decrease in peripheral surface dose (PSD). In this work, PSD of flattened (FF) and FFF-photon beams was compared. A radiochromic film calibration method to reduce energy dependence was used. PSD was measured at distances from 2 to 50 cm to the field border for different square field sizes, modifying relevant clinical parameters. Also, clinical breast and prostate stereotactic body radiotherapy (SBRT) plans were studied. For square beams, FFF PSD is lower compared with FF PSD (differences ranging from 3 to 64%) and 10 MV FFF yields to the lowest value, for distances greater than 5 cm. For SBRT plans, near and far away from the field border, there is a reduction of PSD for FFF-beams, but the behavior at intermediate distances should be checked depending on the case.
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Affiliation(s)
| | - Aurora Vicedo-González
- Departmento de Física Médica, ERESA Hospital General Universitario de Valencia, Valencia, Spain
| | | | | | - Joan Roselló-Ferrando
- Departmento de Física Médica, ERESA Hospital General Universitario de Valencia, Valencia, Spain
- Departamento de Fisiología, Universidad de Valencia, Valencia, Spain
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García-Fusté M, Devienne A, Romero-Expósito M, Caballero-Pacheco M, Domingo C. Calibration of neutron dosimeters for radiation protection use at the ALBA synchrotron experimental hall. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.108749] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Sánchez-Nieto B, Romero-Expósito M, Terrón J, Irazola L, García Hernández M, Mateos J, Roselló J, Planes D, Paiusco M, Sánchez-Doblado F. External photon radiation treatment for prostate cancer: Uncomplicated and cancer-free control probability assessment of 36 plans. Phys Med 2019; 66:88-96. [DOI: 10.1016/j.ejmp.2019.09.076] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/18/2019] [Accepted: 09/11/2019] [Indexed: 10/25/2022] Open
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Romero-Expósito M, Viñals S, Ortega-Gelabert O, Fernández B, Jiménez-Bonilla P, Praena J, Domingo C. CHARACTERIZATION OF THE EPITHERMAL NEUTRON FIELD PRODUCED BY p+7Li REACTION IN A TANDEM ACCELERATOR USING A BONNER SPHERE SPECTROMETER. Radiat Prot Dosimetry 2018; 180:80-84. [PMID: 29669138 DOI: 10.1093/rpd/ncy061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Indexed: 06/08/2023]
Abstract
The proton beam produced in the Nuclear Physics line of the tandem accelerator of the Centro Nacional de Aceleradores was used to generate a neutron field. In particular, 1.912 MeV protons were used to produce well-known epithermal neutrons through the p+7Li → n+7Be reaction. The aim of the work was to characterize this field while testing the performance of a Bonner sphere spectrometer in the epithermal range. Measurements were performed in four locations at different angle (0°, 30°, 60° and 90°) from beam incidence direction in order to study the angular dependence of the field. Both a parametric and numerical unfolding methods were tested to process the counts of the central detectors and obtain the energy distribution of the neutron fluence. In addition, a Monte Carlo simulation was carried out to complete the study and provide a guess spectrum for numerical unfolding. It was found that the fluence rate and mean energy decrease as the angle from beam direction increases. Total fluence was 2.75, 1.36, 0.366 and 0.216 cm-2 per charge collected in the target at 0°, 30°, 60° and 90°, respectively. Mean energy of the field ranges from 46 to 17 keV at 0° and 60°, respectively. In all cases, given that the irradiation room is so large, the contribution of thermal neutrons to the field is small. Regarding the unfolding, the total fluences estimated by all methods were in agreement within the uncertainties.
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Affiliation(s)
- M Romero-Expósito
- Grup de Recerca en Radiacions Ionitzants, Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - S Viñals
- Grup de Recerca en Radiacions Ionitzants, Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - O Ortega-Gelabert
- Grup de Recerca en Radiacions Ionitzants, Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - B Fernández
- Centro Nacional de Aceleradores (U. Sevilla, CSIC, Junta de Andalucía), Sevilla, Spain
| | - P Jiménez-Bonilla
- Departamento de Física Atómica, Molecular y Nuclear, Universidad de Sevilla, Sevilla, Spain
| | - J Praena
- Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, Granada, Spain
| | - C Domingo
- Grup de Recerca en Radiacions Ionitzants, Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
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Kneževic Ž, Ambrozova I, Domingo C, De Saint-Hubert M, Majer M, Martínez-Rovira I, Miljanic S, Mojzeszek N, Porwol P, Ploc O, Romero-Expósito M, Stolarczyk L, Trinkl S, Harrison RM, Olko P. COMPARISON OF RESPONSE OF PASSIVE DOSIMETRY SYSTEMS IN SCANNING PROTON RADIOTHERAPY-A STUDY USING PAEDIATRIC ANTHROPOMORPHIC PHANTOMS. Radiat Prot Dosimetry 2018; 180:256-260. [PMID: 29165619 DOI: 10.1093/rpd/ncx254] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Proton beam therapy has advantages in comparison to conventional photon radiotherapy due to the physical properties of proton beams (e.g. sharp distal fall off, adjustable range and modulation). In proton therapy, there is the possibility of sparing healthy tissue close to the target volume. This is especially important when tumours are located next to critical organs and while treating cancer in paediatric patients. On the other hand, the interactions of protons with matter result in the production of secondary radiation, mostly neutrons and gamma radiation, which deposit their energy at a distance from the target. The aim of this study was to compare the response of different passive dosimetry systems in mixed radiation field induced by proton pencil beam inside anthropomorphic phantoms representing 5 and 10 years old children. Doses were measured in different organs with thermoluminescent (MTS-7, MTS-6 and MCP-N), radiophotoluminescent (GD-352 M and GD-302M), bubble and poly-allyl-diglycol carbonate (PADC) track detectors. Results show that RPL detectors are the less sensitive for neutrons than LiF TLDs and can be applied for in-phantom dosimetry of gamma component. Neutron doses determined using track detectors, bubble detectors and pairs of MTS-7/MTS-6 are consistent within the uncertainty range. This is the first study dealing with measurements on child anthropomorphic phantoms irradiated by a pencil scanning beam technique.
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Affiliation(s)
- Ž Kneževic
- Ruder Boškovic Institute, Bijenicka cesta 54, Zagreb, Croatia
| | - I Ambrozova
- Nuclear Physics Institute of the CAS, Department of Radiation Dosimetry, Na Truhlárce 39/64, Praha, Czech Republic
| | - C Domingo
- Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - M De Saint-Hubert
- Belgium Nuclear Research Center (SCK-CEN), Boeretang 200, Mol, Belgium
| | - M Majer
- Ruder Boškovic Institute, Bijenicka cesta 54, Zagreb, Croatia
| | - I Martínez-Rovira
- Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - S Miljanic
- Ruder Boškovic Institute, Bijenicka cesta 54, Zagreb, Croatia
| | - N Mojzeszek
- Cyclotron Centre Bronowice, Institute of Nuclear Physics, PAN (IFJPAN), Radzikowskiego 152, Krakow, Poland
| | - P Porwol
- Radiology therapeutic Center Poland SP. Z O.O., Centrum Radioterapii Amethyst w Krakowie, Zlotej Jesieni 1, Krakow, Poland
| | - O Ploc
- Nuclear Physics Institute of the CAS, Department of Radiation Dosimetry, Na Truhlárce 39/64, Praha, Czech Republic
| | - M Romero-Expósito
- Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - L Stolarczyk
- Cyclotron Centre Bronowice, Institute of Nuclear Physics, PAN (IFJPAN), Radzikowskiego 152, Krakow, Poland
| | - S Trinkl
- Helmholtz Zentrum München, Institute of Radiation Protection, Ingolstädter Landstraße 1, Neuherberg, Germany
- Technische Universität München, Physik-Department, James-Franck-Str. 1, Garching bei München, Germany
| | - R M Harrison
- University of Newcastle upon Tyne, Tyne and Wear, Newcastle upon Tyne, UK
| | - P Olko
- Cyclotron Centre Bronowice, Institute of Nuclear Physics, PAN (IFJPAN), Radzikowskiego 152, Krakow, Poland
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Stolarczyk L, Trinkl S, Romero-Expósito M, Mojżeszek N, Ambrozova I, Domingo C, Davídková M, Farah J, Kłodowska M, Knežević Ž, Liszka M, Majer M, Miljanić S, Ploc O, Schwarz M, Harrison RM, Olko P. Dose distribution of secondary radiation in a water phantom for a proton pencil beam-EURADOS WG9 intercomparison exercise. Phys Med Biol 2018; 63:085017. [PMID: 29509148 DOI: 10.1088/1361-6560/aab469] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Systematic 3D mapping of out-of-field doses induced by a therapeutic proton pencil scanning beam in a 300 × 300 × 600 mm3 water phantom was performed using a set of thermoluminescence detectors (TLDs): MTS-7 (7LiF:Mg,Ti), MTS-6 (6LiF:Mg,Ti), MTS-N (natLiF:Mg,Ti) and TLD-700 (7LiF:Mg,Ti), radiophotoluminescent (RPL) detectors GD-352M and GD-302M, and polyallyldiglycol carbonate (PADC)-based (C12H18O7) track-etched detectors. Neutron and gamma-ray doses, as well as linear energy transfer distributions, were experimentally determined at 200 points within the phantom. In parallel, the Geant4 Monte Carlo code was applied to calculate neutron and gamma radiation spectra at the position of each detector. For the cubic proton target volume of 100 × 100 × 100 mm3 (spread out Bragg peak with a modulation of 100 mm) the scattered photon doses along the main axis of the phantom perpendicular to the primary beam were approximately 0.5 mGy Gy-1 at a distance of 100 mm and 0.02 mGy Gy-1 at 300 mm from the center of the target. For the neutrons, the corresponding values of dose equivalent were found to be ~0.7 and ~0.06 mSv Gy-1, respectively. The measured neutron doses were comparable with the out-of-field neutron doses from a similar experiment with 20 MV x-rays, whereas photon doses for the scanning proton beam were up to three orders of magnitude lower.
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Affiliation(s)
- L Stolarczyk
- Institute of Nuclear Physics PAN, Radzikowskiego 152, 31-342 Krakow, Poland. Skandionkliniken, von Kraemers Allé 26, 752 37 Uppsala, Sweden. Author to whom any correspondence should be addressed
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Sánchez-Nieto B, Romero-Expósito M, Terrón JA, Sánchez-Doblado F. Uncomplicated and Cancer-Free Control Probability (UCFCP): A new integral approach to treatment plan optimization in photon radiation therapy. Phys Med 2017; 42:277-284. [PMID: 28392313 DOI: 10.1016/j.ejmp.2017.03.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/24/2017] [Accepted: 03/29/2017] [Indexed: 12/25/2022] Open
Abstract
PURPOSE Biological treatment plan evaluation does not currently consider second cancer induction from peripheral doses associated to photon radiotherapy. The aim is to propose a methodology to characterize the therapeutic window by means of an integral radiobiological approach, which considers not only Tumour Control Probability (TCP) and Normal Tissue Complication Probability (NTCP) but also Secondary Cancer Probability (SCP). METHODS Uncomplicated and Cancer-Free Control Probability (UCFCP) function has been proposed assuming a statistically uncorrelated response for tumour and normal tissues. The Poisson's and Lyman's models were chosen for TCP and NTCP calculations, respectively. SCP was modelled as the summation of risks associated to photon and neutron irradiation of radiosensitive organs. For the medium (>4Gy) and low dose regions, mechanistic and linear secondary cancer risks models were used, respectively. Two conformal and intensity-modulated prostate plans at 15MV (same prescription dose) were selected to illustrate the UCFCP features. RESULTS UCFCP exhibits a bell-shaped behaviour with its maximum inside the therapeutic window. SCP values were not different for the plans analysed (∼2.4%) and agreed with published epidemiological results. Therefore, main differences in UCFCP came from differences in rectal NTCP (18% vs 9% for 3D-CRT and IMRT, respectively). According to UCFCP values, the evaluated IMRT plan ranked first. CONCLUSIONS The level of SCP was found to be similar to that of NTCP complications which reinforces the importance of considering second cancer risks as part of the possible late sequelae due to treatment. Previous concerns about the effect of peripheral radiation, especially neutrons, in the induction of secondary cancers can be evaluated by quantifying the UCFCP.
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Affiliation(s)
- Beatriz Sánchez-Nieto
- Instituto de Física, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4880, Macul, Santiago, Chile.
| | - Maite Romero-Expósito
- Departament de Física, Universitat Autònoma de Barcelona, Edifici C, Campus UAB E-08193, Bellaterra, Spain.
| | - José A Terrón
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Av. Doctor Fedriani, 3, 41009 Sevilla, Spain.
| | - Francisco Sánchez-Doblado
- Servicio de Radiofísica, Hospital Universitario Virgen Macarena, Av. Doctor Fedriani, 3, 41009 Sevilla, Spain; Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Av. Doctor Fedriani S/N, 41009 Sevilla, Spain.
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Romero-Expósito M, Domingo C, Sánchez-Doblado F, Ortega-Gelabert O, Gallego S. Experimental evaluation of neutron dose in radiotherapy patients: Which dose? Med Phys 2016; 43:360. [PMID: 26745929 DOI: 10.1118/1.4938578] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The evaluation of peripheral dose has become a relevant issue recently, in particular, the contribution of secondary neutrons. However, after the revision of the Recommendations of the International Commission on Radiological Protection, there has been a lack of experimental procedure for its evaluation. Specifically, the problem comes from the replacement of organ dose equivalent by the organ-equivalent dose, being the latter "immeasurable" by definition. Therefore, dose equivalent has to be still used although it needs the calculation of the radiation quality factor Q, which depends on the unrestricted linear energy transfer, for the specific neutron irradiation conditions. On the other hand, equivalent dose is computed through the radiation weighting factor wR, which can be easily calculated using the continuous function provided by the recommendations. The aim of the paper is to compare the dose equivalent evaluated following the definition, that is, using Q, with the values obtained by replacing the quality factor with wR. METHODS Dose equivalents were estimated in selected points inside a phantom. Two types of medical environments were chosen for the irradiations: a photon- and a proton-therapy facility. For the estimation of dose equivalent, a poly-allyl-diglicol-carbonate-based neutron dosimeter was used for neutron fluence measurements and, additionally, Monte Carlo simulations were performed to obtain the energy spectrum of the fluence in each point. RESULTS The main contribution to dose equivalent comes from neutrons with energy higher than 0.1 MeV, even when they represent the smallest contribution in fluence. For this range of energy, the radiation quality factor and the radiation weighting factor are approximately equal. Then, dose equivalents evaluated using both factors are compatible, with differences below 12%. CONCLUSIONS Quality factor can be replaced by the radiation weighting factor in the evaluation of dose equivalent in radiotherapy environments simplifying the practical procedure.
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Affiliation(s)
- M Romero-Expósito
- Grup de Recerca en Radiacions Ionizants (GRRI), Departament de Física, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain
| | - C Domingo
- Grup de Recerca en Radiacions Ionizants (GRRI), Departament de Física, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain
| | - F Sánchez-Doblado
- Departamento de Fisiología Médica y Biofísica, Universidad de Sevilla, Sevilla 41009, SpainServicio de Radiofísica, Hospital Universitario Virgen Macarena, Sevilla 41009, Spain
| | - O Ortega-Gelabert
- Grup de Recerca en Radiacions Ionizants (GRRI), Departament de Física, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain
| | - S Gallego
- Grup de Recerca en Radiacions Ionizants (GRRI), Departament de Física, Universitat Autònoma de Barcelona, Bellaterra 08193, Spain
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Mares V, Romero-Expósito M, Farah J, Trinkl S, Domingo C, Dommert M, Stolarczyk L, Van Ryckeghem L, Wielunski M, Olko P, Harrison RM. A comprehensive spectrometry study of a stray neutron radiation field in scanning proton therapy. Phys Med Biol 2016; 61:4127-40. [PMID: 27171358 DOI: 10.1088/0031-9155/61/11/4127] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The purpose of this study is to characterize the stray neutron radiation field in scanning proton therapy considering a pediatric anthropomorphic phantom and a clinically-relevant beam condition. Using two extended-range Bonner sphere spectrometry systems (ERBSS), Working Group 9 of the European Radiation Dosimetry Group measured neutron spectra at ten different positions around a pediatric anthropomorphic phantom irradiated for a brain tumor with a scanning proton beam. This study compares the different systems and unfolding codes as well as neutron spectra measured in similar conditions around a water tank phantom. The ten spectra measured with two ERBSS systems show a generally similar thermal component regardless of the position around the phantom while high energy neutrons (above 20 MeV) were only registered at positions near the beam axis (at 0°, 329° and 355°). Neutron spectra, fluence and ambient dose equivalent, H (*)(10), values of both systems were in good agreement (<15%) while the unfolding code proved to have a limited effect. The highest H (*)(10) value of 2.7 μSv Gy(-1) was measured at 329° to the beam axis and 1.63 m from the isocenter where high-energy neutrons (E ⩾ 20 MeV) contribute with about 53%. The neutron mapping within the gantry room showed that H (*)(10) values significantly decreased with distance and angular position with respect to the beam axis dropping to 0.52 μSv Gy(-1) at 90° and 3.35 m. Spectra at angles of 45° and 135° with respect to the beam axis measured here with an anthropomorphic phantom showed a similar peak structure at the thermal, fast and high energy range as in the previous water-tank experiments. Meanwhile, at 90°, small differences at the high-energy range were observed. Using ERBSS systems, neutron spectra mapping was performed to characterize the exposure of scanning proton therapy patients. The ten measured spectra provide precise information about the exposure of healthy organs to thermal, epithermal, evaporation and intra-nuclear cascade neutrons. This comprehensive spectrometry analysis can also help in understanding the tremendous literature data based rem-counters while also being of great value for general neutron shielding and radiation safety studies.
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Affiliation(s)
- Vladimir Mares
- Helmholtz Zentrum München, Institute of Radiation Protection, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
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Irazola L, Ortiz-Seidel M, Velázquez S, García-Hernández M, Terrón J, Sánchez-Nieto B, Romero-Expósito M, Roselló J, Sánchez-Doblado F. EP-1613: Comparison of peripheral doses associated to SBRT, VMAT, IMRT, FFF and 3D-CRT plans for lung cancer. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)32864-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sánchez-Nieto B, El-far R, Irazola L, Romero-Expósito M, Lagares JI, Mateo JC, Terrón JA, Doblado FS. Analytical model for photon peripheral dose estimation in radiotherapy treatments. Biomed Phys Eng Express 2015. [DOI: 10.1088/2057-1976/1/4/045205] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Farah J, Mares V, Romero-Expósito M, Trinkl S, Domingo C, Dufek V, Klodowska M, Kubancak J, Knežević Ž, Liszka M, Majer M, Miljanić S, Ploc O, Schinner K, Stolarczyk L, Trompier F, Wielunski M, Olko P, Harrison RM. Measurement of stray radiation within a scanning proton therapy facility: EURADOS WG9 intercomparison exercise of active dosimetry systems. Med Phys 2015; 42:2572-84. [DOI: 10.1118/1.4916667] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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García Hernández T, Ortiz M, Irazola L, Terrón J, Romero-Expósito M, Sánchez-Nieto B, Sánchez-Doblado F. PO-0868: Neutron peripheral dose estimation: treatment planning system implementation. Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)40860-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Romero-Expósito M, Sánchez-Nieto B, Terrón JA, Lopes MC, Ferreira BC, Grishchuk D, Sandín C, Moral-Sánchez S, Melchor M, Domingo C, Gómez F, Sánchez-Doblado F. Commissioning the neutron production of a Linac: Development of a simple tool for second cancer risk estimation. Med Phys 2014; 42:276-81. [DOI: 10.1118/1.4903525] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Stolarczyk L, Knežević Ž, Adamek N, Algranati C, Ambrozova I, Domingo C, Dufek V, Farah J, Fellin F, Klodowska M, Kubancak J, Liszka M, Majer M, Mares V, Miljanić S, Ploc O, Romero-Expósito M, Schinner K, Schwarz M, Trinkl S, Trompier F, Wielunski M, Harrison R, Olko P. Comparison of passive dosimeters for secondary radiation measurements in scanning proton radiotherapy. Phys Med 2014. [DOI: 10.1016/j.ejmp.2014.07.197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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