Bilateral salpingo-oophorectomy and breast cancer risk for BRCA1 and BRCA2 mutation carriers: Assessing the evidence
Cet article passe en revue les études analysant l'association entre une salpingo-ovariectomie prophylactique bilatérale et le risque de cancer du sein chez les femmes porteuses d'une mutation BRCA
Without preventive interventions, women with germline pathogenic variants in BRCA1 or BRCA2 have high lifetime risks for breast cancer (BC) and tubo-ovarian cancer. The increased risk for BC starts at a considerably younger age than that for tubo-ovarian cancer. Risk-reducing bilateral salpingo-oophorectomy (rrBSO) is effective in reducing tubo-ovarian cancer risk for BRCA1 and BRCA2 mutation carriers, but whether it reduces BC risk is less clear. All studies of rrBSO and BC risk are observational in nature, and subject to various forms of bias and confounding, thus limiting conclusions that can be drawn about causation. Early studies supported a statistically significant protective association for rrBSO on BC risk, which is reflected by several international guidelines that recommend consideration of pre-menopausal rrBSO for BC risk reduction. However, these historical studies were hampered by the presence of several important biases, including immortal person-time bias, confounding by indication, informative censoring, and confounding by other risk factors, which may have led to over-estimation of any protective benefit. Contemporary studies, specifically designed to reduce some of these biases, have yielded contradictory results. Taken together, there is no clear and consistent evidence for a role of pre-menopausal rrBSO in reducing BC risk in BRCA1 or BRCA2 mutation carriers.