An Investigation into the Surface Dose Using Eclipse Treatment Planning System and Film Dosimetry for Treatment of Breast Cancer

Abstract

Purpose: Accurate knowledge about surface dose distribution is a critical issue in skin irradiation. This study was conducted to investigate the surface dose using the Eclipse Treatment Planning System (TPS) calculation and GAF chromic film measurement for breast cancer treatment. Materials and Methods: An inhomogeneous chest phantom was used in the present study. Irradiations were done with a 6 MV energy beam of a linear accelerator (Varian 2100C/D). TPS calculations and film measurements were compared for surface dose estimations. Results: The average difference between film measurements and TPS calculations was 7.1%. Surface doses were lower in TPS calculations in comparison with film measurements. Conclusion: TPS plays a significant role in radiotherapy. However, they have many errors in measuring surface doses. Because of the inaccuracy of the majority of treatment planning systems in calculating the surface dose, the need for practical measurements is essential.

Keywords

• Film Dosimetry
• Surface Dose
• Treatment Planning System