No difference in dose distribution in organs at risk in postmastectomy radiotherapy with or without breast implant reconstruction

摘要

The aim of this study was to quantify the variation in doses to organs at risk (ipsilateral lung and heart) and the clinical target volume (CTV) in the presence of breast implants. In this retrospective cohort study, patients were identified through the National Breast Cancer Register. Consecutive breast cancer patients undergoing mastectomy between 2009 and 2011 and completing a full course of postmastectomy radiotherapy (PMRT) were eligible. All included patients (n?=?818) were identified in the ARIA? oncology information system and further stratified for immediate breast reconstruction (IBR+, n?=?162) and no immediate breast reconstruction (IBR-, n?=?656). Dose statistics for ipsilateral lung, heart and CTV were retrieved from the system. Radiation plans for patients with chest wall (CW) only (n?=?242) and CW plus lymph nodes (n?=?576) irradiation were studied separately. The outcome variables were dichotomized as follows: lung, V20Gy?≤?30% vs. V20Gy?>?30%; heart, Dmean?≤?5 Gy vs. Dmean?>?5 Gy; CTV, V95%?≥?median vs. V95%?