Background/Aim: To determine the incidence of pectus excavatum (PE) and define anatomical chest wall metrics predictive of elevated mean heart dose (MHD) in patients with left-sided breast cancer receiving adjuvant radiotherapy. Patients and Methods: We reviewed 273 consecutively simulated patients from 1/2013-12/2014. Physical examination identified patients with clinically identifiable PE. Characteristics were compared between patients with and those without PE. Predictors of MHD were evaluated using linear regression. Results: The average MHD for the entire cohort was 172 cGy. Of 273 patients, 10 (3.7%) were found to have clinically significant PE. Increase in the Haller Index was correlated with higher MHD (p<0.001). Through the use of individually optimized patient positioning and respiratory gating, MHD was not statistically different in patients with PE compared to those without (p=0.093). Conclusion: Although PE deformity is associated with unfavorable geometry in patients undergoing left-sided breast irradiation, carefully selected treatment technique can maintain acceptable MHD.
