Cancer risk management in Tasmanian women with BRCA1 and BRCA2 mutations

Women carrying germline mutations in BRCA1 or BRCA2 have significantly increased lifetime risks of breast and tubo-ovarian cancer. To manage the breast cancer risk women may elect to have breast screening by MRI/mammogram from age 30, to take risk-reducing medication, or to have a prophylactic bilateral mastectomy. To manage the tubo-ovarian cancer risk, the only effective strategy is to have a bilateral salpingo-oophorectomy, recommended by age 40 (BRCA1) or ‘around’ age 40 (BRCA2). Early studies suggested that uptake of these cancer risk-reducing strategies was low. More recent studies have revealed higher rates of uptake, however it is unclear whether uptake is genuinely improving or whether the higher uptake rates reflect changes in the populations studied. In this study we surveyed 193 BRCA1/2 mutation carriers in the state of Tasmania to determine the uptake of cancer risk-reducing strategies and what factors might influence women’s decisions in relation to both gynaecological and breast surgery. We observed that uptake of risk management strategies varied depending on the strength of the recommendation in the national guidelines. Uptake rates were > 90% for strategies which are strongly recommended, such as breast screening by MRI/mammogram and bilateral salpingo-oophorectomy, and were unaffected by demographic factors such as socio-economic disadvantage and educational achievement. Uptake rates were much lower for strategies which are presented in the guidelines as options for consideration and where patient choice and shared decision making are encouraged, such as prophylactic mastectomy (29%) and chemoprevention (1%) and in the case of prophylactic mastectomy, were influenced by both socio-economic advantage and educational achievement.