Breast-Conserving Surgery or Mastectomy?: Impact on Survival

Area of Science:

• Oncology
• Surgical Oncology
• Epidemiology

Background:

• Early trials found no survival difference between breast-conserving surgery (BCS) and mastectomy.
• Recent population-based studies suggest improved long-term survival with BCS.

Purpose of the Study:

• To systematically review and meta-analyze recent population-based observational studies on BCS versus mastectomy survival outcomes.
• To evaluate current evidence on the comparative effectiveness of BCS and mastectomy.

Main Methods:

• Systematic literature search of PubMed, Embase, and Cochrane databases.
• Meta-analysis of hazard ratios (HRs) for overall survival (OS) and breast cancer-specific survival (BCSS) using random-effects models.
• Inclusion of 30 reports, with 25 studies contributing to meta-analyses.

Main Results:

• BCS was associated with significantly better OS (HR=1.34) and BCSS (HR=1.38) compared to mastectomy.
• Subgroup analyses by lymph node status, age, and radiation therapy confirmed improved OS with BCS.
• No significant moderation of survival differences by the number or type of prognostic variables adjusted for.

Conclusions:

• Current evidence from large population-based studies indicates a survival benefit for BCS over mastectomy.
• BCS should be considered the recommended treatment for early breast cancer (T1-2N0-1M0) when radical lumpectomy is achievable.