Risk-reducing bilateral mastectomy confers survival benefit in BRCA carriers

Risk-reducing bilateral mastectomy in patients with the BRCA pathogenic variant appears to be associated with lower overall and breast-cancer specific mortality, according to a meta-analysis.

Researchers searched multiple online databases for studies in which the effect of risk-reducing bilateral mastectomy on mortality outcomes in female carriers of BRCA pathogenic variants was evaluated. Studies including patients with a history of breast cancer were excluded.

A total of six observational studies met the inclusion criteria, with the overall population comprising 6,135 carriers (median age at inclusion 38 years) of the BRCA1 or BRCA2 variant. Of these, 2,558 patients underwent risk-reducing bilateral mastectomy, and the 3,577 who did not were designated as controls.

The overall median follow-up duration was 75.6 months, and the primary outcomes were overall and breast cancer–specific mortality.

Pooled data showed that compared with the control group, the risk-reducing bilateral mastectomy group had significantly reduced overall mortality in both unadjusted (odds ratio [OR], 0.38, 95 percent confidence interval [CI], 0.27–0.55; p<0.001) and adjusted (hazard ratio [HR], 0.37, 95 percent CI, 0.23–0.60; p<0.001) analyses.

Similarly, patients who did vs did not undergo risk-reducing bilateral mastectomy had markedly lower breast cancer–specific mortality in the unadjusted (OR, 0.19, 95 percent CI, 0.08–0.47; p<0.001) and adjusted (HR, 0.14, 95 percent CI, 0.04–0.49; p=0.002) analyses.

The findings highlight the potential of risk-reducing bilateral mastectomy as a life-extending intervention and may inform the shared decision-making discussions in this population.