Monte Carlo calculation of absorbed dose in breast radiotherapy due to photon beams of different energies

Abstract

In this study, breast cancer treatment reproduced from a VARIAN eclipse planning system is simulated. This treatment was simulate using the Monte Carlo system. To this end, the body of the woman is simulate by the geometry of the Phantom FAX06, which was reproduced using the ImageJ software that allowed the import and conversion of DICOM images into valid input files for the MCNPX code. Additionally, geometry of the linear accelerator head (including the MLC) was constructed. Co-60 photons, 6 and 15 MV photon spectra were simulate with an angle that allowed for the recreation of two tangential fields used in conventional radiation therapy treatments for breast cancer. The main objective of this study was to estimate the absorbed dose in each of the organs involved in this type of treatment and for each of the sources simulated. The result allowed us to establish the differences between the absorbed dose that is transferred to the target organ and that which is transferred to the organs at risk, such as the heart and lungs. The dose absorbed in organs at risk and target organ when Co-60 is used has advantages over the use of 6 and 15 MV beams, these results should be considered by the manufacturers of LINAC’S and by the scientific community. The proposal in this sense is to manufacture a device with Co-60 and with the technology of a LINAC for the treatment of some cancer.