Pre-treatment predictors of cardiac dose exposure in left-sided breast cancer radiotherapy patients after breast conserving surgery

Abstract Objectives This study aimed to identify high-risk factors for high cardiac radiation exposure, based on anatomical measurements taken from planning CT images of patients with left-sided breast cancer who underwent breast-conserving surgery and received radiotherapy. Methods We retrospectively analyzed 45 whole-breast radiotherapy, either under free breathing (27/45) or deep inspiratory breath-holding (DIBH) (18/45), after surgery. Six parameters were measured images, including treatment target volume (PTV), cardiopulmonary ratio (CVR), maximum margin distance, the relative distance between inferior boundaries heart PTV (DBIB(H2P)), axial contact para-sagittal (CCDps). Multiple linear regression analysis was performed using SPSS software explore correlation six parameters, body mass index (BMI), mean dose (MHD). Receiver operating characteristic (ROC) evaluate predictive power selected predictor exposure. Results Significant correlations observed MHD CVR, DBIB(H2P), CCDps parameters. Among them, CVR most important an area curve 0.915 a cut-off value 0.17. Conclusions The results indicated that are primary associated risk being significant predictor. Further prospective studies required determine whether these can be used would benefit DIBH technique.