Dosimetric Comparison of Three-Dimensional Conformal Radiotherapy under Deep Inspiration Breath-Hold and Free-Breathing Conditions and Volumetric Modulated Arc Therapy for Left-Sided Breast Cancer

Background and purpose: Radiotherapy for left-sided breast cancer may result in unintended radiation to the heart and left lung, and deep inspiration breath-hold (DIBH) can reduce this dose by increasing the distance between the heart and the chest wall. The aim of this study was to compare the dose received by the target volume and organs at risk in 3D-CRT techniques during free breathing (FB) and breath-hold, as well as in VMAT, in patients with left-sided breast cancer.

Materials and methods

In this dosimetric comparative study, ten patients with left-sided breast cancer scheduled for radiotherapy were enrolled. For each patient, CT simulation were acquired under FB and DIBH conditions. The mean doses to the target volume (CTV) and OARs, along with dose-volume parameters, including V95%, V98%, and V100% for the CTV and V25%, V20%, V10%, V5%, and V2% for the OARs, were extracted from dose-volume histograms (DVHs). Data were analysed using SPSS version 22 (P < 0.05).