Preparation of a radiobiology beam line at the 18 MeV proton cyclotron facility at CNA

Proton therapy has gained interest in recent years due to its excellent clinical outcomes. However, the lack of accurate biological data, especially in the Bragg peak region of clinical beams, makes it difficult to implement biophysically optimized treatment plans in clinical practice. In this conte...

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Detalles Bibliográficos
Autores: Baratto Roldán, Anna, Jiménez Ramos, María del Carmen, Jimeno González, Sonia, Huertas Sánchez, Pablo, García López, Francisco Javier, Gallardo Fuentes, María Isabel, Cortés Giraldo, Miguel Antonio, Espino Navas, José Manuel
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/166847
Acceso en línea:https://hdl.handle.net/11441/166847
https://doi.org/10.1016/j.ejmp.2020.04.022
Access Level:acceso abierto
Palabra clave:Dosimetry
Monte Carlo simulations
Proton beams
Radiobiology
Radiochromic films
Descripción
Sumario:Proton therapy has gained interest in recent years due to its excellent clinical outcomes. However, the lack of accurate biological data, especially in the Bragg peak region of clinical beams, makes it difficult to implement biophysically optimized treatment plans in clinical practice. In this context, low energy proton accelerator facilities provide the perfect environment to collect good radiobiological data, as they can produce high LET beams with narrow energy distributions. This study presents the radiobiology beam line that has been designed at the 18 MeV proton cyclotron facility at the National Centre of Accelerators (CNA, Seville, Spain), to perform irradiations of mono-layer cell cultures. To ensure that all the cells receive the same dose with a suitable dose rate, low beam intensities and broad and homogeneous beam profiles are necessary. To do so, at the CNA an unfocused beam has been used, broadened with a 500 μm thick aluminium scattering foil. Homogeneous dose profiles, with deviations lower than 10% have been obtained over a circular surface of 35 mm diameter for an incident average energy of 12.8 MeV. Further, a Monte Carlo simulation of the beam line has been developed with Geant4, and benchmarked towards experimental measurements, with differences generally below 1%. Once validated, the code has been used, together with an ionization chamber, for dosimetry studies, to characterize the beam and monitor the dose. Finally, cultures of Human Bone Osteosarcoma cells (U2OS) have been successfully irradiated at the radiobiology beam line, investigating the effects of radiation in terms of DNA damage induction.