Effect of BRCA1/2 mutation on short-term and long-term breast cancer survival: a systematic review and meta-analysis

Reports of BRCA genetic mutations and risk of death or recurrence are inconsistent. This study aimed to compare overall and disease-free breast cancer survival rates between BRCA1/2 mutation carriers and non-carriers for short-term and long-term outcomes separately. We searched the PUBMED and EMBASE databases and retrieved 452 articles using keywords that included breast cancer, BRCA mutation, and survival. Seventeen articles were selected for systematic review and among them 11 were included in our meta-analysis. We used the random-effects model to calculate the summary hazard ratio and corresponding 95% confidence interval. BRCA1 mutation carriers had significantly lower short-term and long-term overall survival rates (OSR) relative to non-carriers (HR = 1.92 [95% CI = 1.45-2.53]; 1.33 [1.12-1.58], respectively), while both short-term and long-term OSR of BRCA2 carriers did not differ from non-carriers (HR = 1.30 [95% CI = 0.95-1.76]; 1.12 [95% CI = 0.86-1.45], respectively). For short-term progression-free survival rate (PFSR), BRCA1 mutation carriers had a significantly lower rate than non-carriers (HR = 1.54 [95% CI = 1.12-2.12]), while BRCA2 mutation carriers had a similar PFSR (HR = 1.23 [95% CI = 0.96-1.58]). For long-term PFSRs, we found no significant results. Our results suggest that BRCA1 mutation decreases short-term and long-term OSRs and short-term PFSR, however, BRCA2 mutation does not affect either short-term or long-term survival rate, which is attributed to the different carcinogenic pathways for BRCA1 and BRCA2.