- Risk-reducing surgery for BRCA-positive women is tied to substantially reduced incidence of breast and/or ovarian cancer, but not to decreased overall mortality, according to a retrospective cohort study.
Why this matters
- BRCA-positive women considering risk-reducing mastectomy (RRM) and/or salpingo-oophorectomy (RRSO) should be informed about this divergence in benefit between overall mortality and incidence reduction.
- Further research is warranted.
- 20-year retrospective, population-based cohort in Western Sweden, all BRCA1/2-positive women who were cancer-free at the time of registration, 1995-2016 (N=253).
- Incidence and mortality data from Swedish Cancer Register were compared with the general population.
- Funding: Swedish government and city councils.
- Standard incidence ratio (SIR) for breast cancer:
- Until RRM: 14.0 (95% CI, 9.42-20.7).
- After RRM: 1.93 (95% CI, 0.48-7.7).
- SIR for ovarian cancer:
- Until RRSO: 124.6 (95% CI, 59.4-261.3).
- After RRSO: 13.5 (95% CI, 4.34-41.8).
- Standard mortality ratio (SMR):
- Before risk-reducing surgery: 5.56 (95% CI, 2.09-14.8).
- After both RRM and RRSO: 4.32 (95% CI, 1.62-11.5).
- Number of deaths was low for statistical purposes (n=16).
- The study does not reflect the effect of new prophylactic medications or new medications for breast or ovarian cancer.