Secondary neutron doses in proton therapy treatments of ocular melanoma and craniopharyngioma.
Monte Carlo simulations were used to assess secondary neutron doses received by patients treated with proton therapy for ocular melanoma and craniopharyngioma. MCNPX calculations of out-of-field doses were done for ∼20 different organs considering realistic treatment plans and using computational phantoms representative of an adult male individual. Simulations showed higher secondary neutron doses for intracranial treatments, ∼14 mGy to the salivary glands, when compared with ocular treatments, ∼0.6 mGy to the non-treated eye. This secondary dose increase is mainly due to the higher proton beam energy (178 vs. 75 MeV) as well as to the impact of the different beam parameters (modulation, collimation, field size etc.). Moreover, when compared with published data, the assessed secondary neutron doses showed similar trends, but sometimes with sensitive differences. This confirms secondary neutrons to be directly dependent on beam energy, modulation technique, treatment configuration and methodology.
Institut de Radioprotection et de Sûreté Nucléaire (IRSN) - PRP-HOM/SDE - BP17, 92262 Fontenay-aux-Roses Cedex, France jad.farah@irsn.fr.
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Farah
Institut de Radioprotection et de Sûreté Nucléaire (IRSN) - PRP-HOM/SDE - BP17, 92262 Fontenay-aux-Roses Cedex, France.
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Sayah
Institut de Radioprotection et de Sûreté Nucléaire (IRSN) - PRP-HOM/SDE - BP17, 92262 Fontenay-aux-Roses Cedex, France.
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Martinetti
Institut de Radioprotection et de Sûreté Nucléaire (IRSN) - PRP-HOM/SDE - BP17, 92262 Fontenay-aux-Roses Cedex, France.
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Donadille
Institut de Radioprotection et de Sûreté Nucléaire (IRSN) - PRP-HOM/SDE - BP17, 92262 Fontenay-aux-Roses Cedex, France.
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Lacoste
Centre Antoine Lacassagne (CAL) - Cyclotron biomédical, 227 avenue de la Lanterne, 06200 Nice, France.
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Hérault
Institut Curie - Centre de Protonthérapie d'Orsay (ICPO) - Campus universitaire bâtiment 101, 91898 Orsay, France.
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Delacroix
Institut Curie - Centre de Protonthérapie d'Orsay (ICPO) - Campus universitaire bâtiment 101, 91898 Orsay, France.
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Nauraye
Institut de physique nucléaire (IPN), 91406 Orsay Cedex, France.
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Vabre
Division of Cancer Epidemiology and Genetics, National Institute of Health, Bethesda, MD 20852, USA.
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Lee
Departments of Nuclear & Radiological and Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA.
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Bolch
Institut de Radioprotection et de Sûreté Nucléaire (IRSN) - PRP-HOM/SDE - BP17, 92262 Fontenay-aux-Roses Cedex, France.
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Clairand
D000328:Adult; D003198:Computer Simulation; D003397:Craniopharyngioma / Q000532:radiotherapy*; D005123:Eye / Q000528:radiation effects; D005134:Eye Neoplasms / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008545:Melanoma / Q000532:radiotherapy*; D008962:Models, Theoretical; D009010:Monte Carlo Method; D009502:Neutrons; D019047:Phantoms, Imaging; D061766:Proton Therapy / Q000009:adverse effects* / Q000379:methods*; D011829:Radiation Dosage; D011874:Radiometry; D011879:Radiotherapy Dosage; D015203:Reproducibility of Results; D012469:Salivary Glands / Q000528:radiation effects