Dose calculation in gynecological brachytherapy using monte carlo simulation for intracavitary treatment of cervical cancer

Abstract

Intracavitary brachytherapy with high dose rate (HDR) is nowadays one of the complementary specialities for the treatment of cervical cancer. This work presents results of an application for the deposited dose calculation in brachytherapy treatments for cervical cancer using distributed tools in the GAMOS and Geant4, aimed at studying the effects on dose distribution considering the variation of tissue inhomogeneities and decay characteristics for an mHDR-vl Nucletron Classic source. The anatomy of the patient is included in the developed Monte Carlo simulation using CT images of a typical HDR brachytherapy for cervical cancer treatment defining a voxel grid which contains the composition and density information due to body tissues, extracted from CT images, and converted to material voxels through the CT Number characteristic curve. The results obtained are in agreement with values reported by the planning system used, showing a difference possibly due to overestimation due to AAPM Task Group No. 43 formalism, the effect due to variation in tissue and the noise contained in the image.