Introduction: Heterogeneity correction is an important parameter in dose calculation for cancer patients where it may be cause inaccuracy in dose calculation as a result of different densities of patients. This study studied the impact of dose calculation of breast cancer patients with and without heterogeneity correction. Material and Methods: Twenty breast cancer patients were treated with Three-Dimensional Conformal Radiotherapy(3DCRT). Dose calculations were performed using two modes: Fast Photon mode for homogeneity and Fast Photon Effective Path length for heterogeneity with two photon energies. Monitor Units(MU), Modulation Factor, Dose Volume Histograms(DVH) and quality indices were used to evaluate the effect of heterogeneity correction on dose calculation and investigate the mechanism of this effect in the low and high energies.
Results: Heterogeneity correction compared to without it showed significant reduction in MU and modulation factor at 6MVand 10MV (
