The cumulative risk for breast and ovarian cancer is high in BRCA1 or BRCA2 mutation carriers. The lifetime risk of breast cancer by the age of 80 years is respectively up to 72% and 69% in BRCA1 and BRCA2 mutation carriers. The risk of ovarian cancer is higher (44%) in BRCA1 than in BRCA2 (17%) mutation carriers. Breast and ovarian cancers tend to arise earlier in BRCA1 mutation carriers. Breast cancers in BRCA1 mutation carriers are more frequently (up to 70%) triple negative while the majority (up to 80%) of breast cancers in BRCA2 mutation carriers are hormone sensitive. Many issues remain to be resolved. In daily practice we are often confronted with patients having BRCA mutations classified as variants of unknown significance, who do have breast cancer personally or have a strong family history of breast cancer. On the other hand, 30-40% of mutation carriers will not develop breast cancer. Moreover, it is very difficult to predict the age at which cancer will arise. In a multidisciplinary setting we need to offer BRCA and other mutation carriers a wide range of information, advice and support.
Keywords: BRCA; hormone therapy; pregnancy hormone; prophylaxis; surgery.