BRCA1 and breast cancer: Cumulative breast cancer risks are estimated 57–65 % (95 % CIs: 44–78 %) for BRCA1 and 45–49 % (95 % CIs: 31–57 %) for BRCA2 mutation carriers by age 70, whereas cumulative ovarian cancer risks lie around 39–40 % (95 % CIs: 18–54 %) and 11–18 % (95 % CIs: 2.4–23 %) by the age of 70 for BRCA1 en BRCA2, respectively [1, 2].