Nanoscale energy deposition frequencies evaluation using GATE simulation tools

Abstract

Over the last decade, cancer treatment with radiation therapy has evolved significantly due to the improvements in Treatment Planning Systems (TPS). Ideally, these algorithms can determine the dose distribution at the macroscopic scale. However, due to the lack of knowledge, these approaches remain impractical to model radiation side effects at the nanometric scale. This study presents the validation of Monte Carlo (MC) algorithms as a novel approach to model the nanodosimetric effects of radiation therapy particles on real DNA molecule models. A simulation of two simple volumes irradiated by a proton beam is performed to demonstrate the ability of the mixed Geant4-DNA physics model to describe extremely low-energy particle interactions compared to the simple standard Electromagnetic options three physic list. Furthermore, the nanodosimetric effects on the DNA molecule are simulated based on the calculations of the energy frequency deposited by both electron and proton beams in cylinders of three distinct nanometric diameters sizes corresponding to the block elements of the nucleus cell (10 bp, nucleosome, and chromatin fiber). Finally, following the results of this study, the energy deposition frequency in nanoscale cylinders simulated based on the Gate MC code is in good agreement with the results of the series of MOCA codes previously published in the literature.