Comparison between 3D Conformal radiotherapy, Intensity Modulated Radiotherapy and Volumetric Modulated Arc Therapy treatment plans for left sided breast cancer patients using deep inspiration breath hold technique

Comparing between 3-Dimentional conformal radiotherapy (3DCRT), Intensity Modulated Radiotherapy (IMRT), Volumetric Modulated Arc Therapy (VMAT) using Deep Inspiratory Breath Hold (DIBH) techniques regarding target volume coverage and dose to heart and left lung for patients with left sided breast cancer. C-T simulation was done for 25 patients with left sided breast cancer using DIBH through the use of Active breath coordinate device (ABC), 3 plans were done for every patients, one by 3DCRT, second by IMRT and the third using VMAT techniques, comparison between these techniques was done regarding target volume coverage and dose to left lung and heart. The VMAT plans showed significantly higher mean dose coverage to the PTV than that of 3DCRT and IMRT plans (p< 0.001). The VMAT plans demonstrated significantly lower mean doses to OARs than that of 3DCRT and IMRT plans. The maximum heat dose was the least in VMAT plans (p<0.001). Whereas the median dose of the V25 of the heart was also less in the VMAT plans than that of 3DCRT and IMRT plans (p=0.015). Regarding the ipsilateral (left) lung, the median dose of V20 of left lung was the same of the 3 plans with no significant difference between them. The use of VMAT technique with DIBH technique showed better target volume coverage and significant reduction in the heart dose compared to 3DCTH and IMRT using DIBH.