Breast-Conserving Surgery or Mastectomy?: Impact on Survival

The early randomized controlled trials revealed no differences in survival between breast-conserving surgery (BCS) and mastectomy. However, breast cancer treatment has undergone changes, and the results of recent population-based registry studies suggest superior long-term survival after BCS. To explore the current evidence, a systematic review and meta-ana lysis of population-based observational studies from 2010 and onward was conducted. METHODS: A literature search was conducted in the PubMed, Embase, and Cochrane databases to identify relevant literature. Keywords included “mastectomy,” “breast conserving surgery,” and “survival.” The identified studies were narratively reviewed and effect sizes (hazard ratios [HRs]) for overall (OS) and breast cancer-specific survival (BCSS) were combined with random-effects models. RESULTS: A total of 30 reports were included in the review, and results from 25 studies were included in the meta-analyses. Compared with mastectomy, BCS was associated with better OS (HR = 1.34 [1.20–1.51]; N = 1,311,600) and BCSS (HR = 1.38 [1.29–1.47]; N = 494,267). Selected subgroups of patients, based on lymph node status, age (<50 years/≥50 years), and radiation therapy after mastectomy (±), all showed better overall survival after BCS. The number (range 4–12) and type of prognostic variables adjusted for in the survival analyses of the studies did not statistically significantly moderate the differences in survival between BCS and mastectomy. CONCLUSIONS: The combined findings from large population-based studies indicate that BCS is associated with survival benefit compared with mastectomy, suggesting that BCS be the recommended treatment of early breast cancer (T1-2N0-1M0) if a radical lumpectomy can be performed.