Precision prophylaxis: Identifying the optimal timing for risk-reducing salpingo-oophorectomy based on type of BRCA1 and BRCA2 cluster region mutations
Authors: Ian Solsky , Jinbo Chen , Timothy R Rebbeck
Objectives: Current risk-reducing salpingo-oophorectomy (RRSO) guidelines for individuals with BRCA1/2 mutations do not account for risk variability due to BRCA1/2 cluster region mutations that are associated with varying risks for the development of breast and ovarian cancer. We assessed whether current recommendations are appropriate for individual patients considering mutation-specific risks. Methods: Using a hypothetical cohort of patients with BRCA1/2 mutations, we constructed Markov models allowing for the estimation of mean life expectancy based upon BRCA1/2 mutation, the presence of a cluster region mutation (Ovarian Cancer Cluster Region (OCCR), Breast Cancer Cluster Region (BCCR), or non-BCCR/OCCR), age at time of BRCA1/2 diagnosis (20-65), and age at time of RRSO (21-80). Results: For all BRCA1/2 mutation types, the optimal strategy was to undergo RRSO as early as possible. For BRCA1/2 carriers who delayed RRSO or who were identified with a mutation later in life, the OCCR mutation tended to be associated with lower life expectancy estimates than the BCCR and non-BCCR/OCCR mutations. Minimal delays in RRSO (i.e., neighboring 5-year intervals) were associated with minor losses in life expectancy. Variables associated with greatest impact on life expectancy included ovarian cancer risk after RRSO, breast cancer mortality rate, non-cancer mortality associated with RRSO, and breast cancer stage distribution. Conclusions: BRCA1/2 cluster regions may provide more precise estimates of life expectancy in counselling and shared decision-making. The most appropriate timing for RRSO is a complex decision and must be individualized for each patient.
Keywords: BRCA mutations; RRSO; Risk-reducing surgery.