Accurate estimations of lifetime risks of breast and ovarian cancer are crucial for counselling women from BRCA1/2 families. We therefore determined breast and ovarian cancer penetrance in BRCA1/2 mutation families in the northern Netherlands and compared them with the incidence of cancers in the general population in this region. We identified 1188 female mutation carriers and first-degree female relatives in 185 families with a pathogenic BRCA1 or BRCA2 mutation. The occurrence of breast cancer, contralateral breast cancer and ovarian cancer was recorded. The cumulative incidence of breast cancer by age 70 was 71.4% (95% CI 67.2-82.4%) in BRCA1 and 87.5% (82.4-92.6%) in BRCA2 mutation carriers. For ovarian cancer at age 70, it was 58.9% (53.5-64.3%) in BRCA1 and 34.5% (25.0-44.0%) in BRCA2 mutation carriers. For breast cancer we saw a rise of 24.2% in the cumulative incidence in the seventh decade for BRCA2 mutation carriers versus 6.3% for BRCA1. For ovarian cancer the rise in the seventh decade was 17.3% for BRCA1 mutation carriers and 15.1% for BRCA2. The 10-year risk for contralateral breast cancer was 34.2% (29.4-39.0%) in BRCA1 families and 29.2% (22.9-35.5%) in BRCA2. We show that the incidence of breast and ovarian cancer in BRCA2 mutation carriers and of ovarian cancer in BRCA1 mutation carriers is still high after 60 years. This may justify intensive breast screening as well as oophorectomy even after age 60. The risk of contralateral breast cancer rises approximately 3% per year, which may affect preventive choices.

Expanded carrier screening (ECS) aims to inform couples’ reproductive choice, preferably before conception. As part of an implementation study in which trained general practitioners (GPs) offered a population-based ECS couple-test, we evaluated the feasibility of the test-offer and degree of participant informed choice (IC). Trained GPs from nine practices in the northern Netherlands invited 4295 female patients aged 18–40 to take part in couple-based ECS. Inclusion criteria were having a male partner, planning for children and not being pregnant. We evaluated the feasibility of the organizational aspects, GP competence and the content of the pre-test counselling. Participant satisfaction, evaluation of pre-test counselling and degree of IC were measured using a longitudinal survey. We explored GP experiences and their views on future implementation through semi-structured interviews. 130 consultations took place. All participating GPs were assessed by genetic professionals to be competent to conduct pre-test counselling. Most (63/108 (58%)) consultations took place within the planned 20 min (median 20, IQR 18–28). GPs considered couples’ prior knowledge level an important determinant of consultation length. 91% of patients were (very) satisfied with the GP counselling. After pre-test counselling, 231/237(97%) participants had sufficient knowledge and 206/231(88%) had a positive attitude and proceeded with testing. Our pilot demonstrates that offering couple-based ECS through trained and motivated GPs is feasible. Future large-scale implementation requires a well-informed general public and a discussion about appropriate reimbursement for GPs and health care coverage for couples. Providing (more) test information pre-appointment may help reduce average consultation time.

In conclusion, this study shows that BCRP protein is expressed at low but variable levels in AML, especially in immature CD34 ؉ cells. BCRP was not consistently up-regulated in relapsed/refractory AML.