Modelagem da Radiação Secundária em Terapia com Prótons para Câncer de Próstata Usando MCNP
DOI:
https://doi.org/10.29384/rbfm.2026.v20.19849001878Keywords:
Proton Radiotherapy, ; Monte Carlo Simulation, Secondary Dose, ICRP 110 Phantom, Prostate CancerAbstract
This study evaluated the contribution of secondary particles in prostate cancer treatments using a 250 MeV proton beam through Monte Carlo simulations with the MCNP 6.2 code. The adult male reference computational anthropomorphic phantom from ICRP 110 was used, with a realistic modeling of the beam line using a double scattering technique. Equivalent doses received by different organs due to scattered radiation from protons, neutrons, and photons were calculated. Secondary neutrons were the main contributors to out-of-field doses, reaching distant organs such as the brain with relevant levels. Comparison with studies based on photon radiotherapy revealed that proton therapy provides a significant reduction in equivalent doses to sensitive organs, such as the testes. The results reinforce the benefit of proton therapy in preserving healthy tissues, although they highlight the need to carefully consider the effects of secondary radiation, especially from neutrons.
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Copyright (c) 2026 Victória Carmo Silva, Jose Rafael Santos Ferreira, Carla de Jesus Souza Santos, José Willian Santos Prado, Lucio Pereira Neves, Ana Paula Perini, Walmir Belinato, Tiago Ramos Borba, Fellipe Oliveira Ferraz Silva, Arthur de Souza Borges Zuchetti Alves, William de Souza Santos
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