Long-term Survival Outcomes in Patients with Locally Advanced Breast Cancer after Total Mastectomy with or without Breast Reconstruction: A Seer-based Analysis

Abstract

Background: There is ongoing debate about the safety of breast reconstruction for patients with locally advanced breast cancer (LABC) who have undergone total mastectomy (TM). More and more LABC patients are undergoing breast reconstruction after TM, but its long-term survival outcomes remain unclear. This study aims to compare the survival outcomes of LABC patients who underwent breast reconstruction after TM with those who did not, based on a large sample. Methods: We collected data for all LABC patients who underwent TM with or without breast reconstruction in the Surveillance, Epidemiology, and End Results (SEER) database. We divided patients into two groups: TM group and total mastectomy with reconstruction (TM+R) group. The primary outcomes were overall survival (OS) and breast cancer-specific survival (BCSS). Propensity score matching (PSM) analysis was used to eliminate imbalances of baseline data between the in tow groups. Data were analyzed using chi-square tests, Kaplan-Meier methods, and univariate and multivariate cox regression analyses. Result: We identified 39,112 eligible patients (33,169 patients received TM and 5,943 received TM+R), and 8,680 patients were matched after PSM (4,340 patients received TM and 4,340 received TM+R). Patients with middle age, white, married, lived in urban, IIB-IIIA stage, invasive ductal carcinoma(IDC), pathological grade II-III, hormone receptor positive, and undergone chemotherapy were more likely to receive breast reconstruction. After PSM, Kaplan-Meier survival analysis showed better OS and BCSS in the TM+R group versus the TM group (OS:P<0.001; BCSS: P=0.008). Multivariate cox regression analysis showed that TM+R significantly improved OS and BCSS (OS: hazard ratio (HR) 0.73, 95% CI [0.68,0.79], P<0.001; BCSS: 95% CI [0.79,0.94], P=0.001). Subgroup analysis showed that patients with old age, white, and hormone receptor positive had better OS and BCSS by TM+R compared to TM. Conclusions: Breast reconstruction after total mastectomy is associated with better OS and BCSS in patients with LABC.