Marcinkute, R. et al | 2021| Uptake and efficacy of bilateral risk reducing surgery in unaffected female BRCA1 and BRCA2 carriers | Journal of Medical Genetics | Published Online First: 10 February 2021. doi: 10.1136/jmedgenet-2020-107356
This NIHR Alert summarises the recent findings of a longitudinal study that followed more than 800 women who carry the BRCA1 or BRCA2 genes who have an increased risk of developing ovarian and breast cancers (as well as other cancers). After testing positive for these genes, the individuals were followed up twenty years later, where more than half (57.9 per cent) had a risk reducing mastectomy, and 77 per cent had elected for a bilateral salpingo-oophorectomy (RRSO).
Abstract
Background Women testing positive for BRCA1/2 pathogenic variants have high lifetime risks of breast cancer (BC) and ovarian cancer. The effectiveness of risk reducing surgery (RRS) has been demonstrated in numerous previous studies. We evaluated long-term uptake, timing and effectiveness of risk reducing mastectomy (RRM) and bilateral salpingo-oophorectomy (RRSO) in healthy BRCA1/2 carriers.
Methods Women were prospectively followed up from positive genetic test (GT) result to censor date. χ² testing compared categorical variables; Cox regression model estimated HRs and 95% CI for BC/ovarian cancer cases associated with RRS, and impact on all-cause mortality; Kaplan-Meier curves estimated cumulative RRS uptake. The annual cancer incidence was estimated by women-years at risk.
Results In total, 887 women were included in this analysis. Mean follow-up was 6.26 years (range equal to 0.01–24.3; total equal to4685.4 women-years). RRS was performed in 512 women, 73 before GT. Overall RRM uptake was 57.9 per cent and RRSO uptake was 78.6 per cent. The median time from GT to RRM was 18.4 months, and from GT to RRSO–10.0 months. Annual BC incidence in the study population was 1.28 per cent. Relative BC risk reduction (RRM versus non-RRM) was 94 per cent. Risk reduction of ovarian cancer (RRSO versus non-RRSO) was 100 per cent.
Conclusion Over a 24-year period, we observed an increasing number of women opting for RRS. We showed that the timing of RRS remains suboptimal, especially in women undergoing RRSO. Both RRM and RRSO showed a significant effect on relevant cancer risk reduction. However, there was no statistically significant RRSO protective effect on BC.
Uptake and efficacy of bilateral risk reducing surgery in unaffected female BRCA1 and BRCA2 carriers [abstract only]
NIHR Alert Earlier decisions on breast and ovarian surgery reduce cancer in women at high risk
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