Application of Monte Carlo calculations for validation of a treatment planning system in high dose rate brachytherapy

Aim: The accuracy of treatment planning systems is of vital importance in treatment outcomes in brachytherapy. In the current study the accuracy of dose calculations of a high dose rate (HDR) brachytherapy treatment planning system (TPS) was validated using the Monte Carlo method. Materials and methods: Three Co-60 sources of the GZP6 afterloading brachytherapy system were modelled using MCNP4C Monte Carlo (MC) code. The dose distribution around all the sources was calculated by MC and a dedicated treatment planning system. The results of both methods were compared. Results: There was good agreement (<2%) between TPS and MC calculated dose distributions except at a point near the sources (<1 cm) and beyond the tip of the sources. Conclusions: Our study confirmed the accuracy of TPS calculated dose distributions for clinical use in HDR brachytherapy. (C) 2009 Wielkopolskie Centrum Onkologii. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.