Cost-effectiveness of BRCA1 testing at time of obstetrical prenatal carrier screening for cancer prevention

Background Improved technologies paired with an increase in access to genetic testing has led to the availability of expanded carrier screening evaluating hundreds of disorders. Currently, most autosomal dominant mutations, such as BRCA1, are not included in expanded carrier assays. Screening pregnant or preconception reproductive-aged women for BRCA1 may present a unique opportunity to perform population-based screening for patients at a time where precancer screening, chemoprevention and/or risk reducing surgery may be beneficial. Objective The objective of our study was to inform clinical decision making as to whether the universal incorporation of BRCA1 testing at the time of obstetrical prenatal carrier screening is cost-effective. Study Design A decision analysis and Markov model was created. The initial decision point in the model was BRCA1 testing at the time of expanded carrier screening. Model probabilities, cost, and utility values were derived from published literature. For BRCA1-positive patients, the model simulated breast cancer screening and risk-reducing surgical interventions. A cycle length of 1 year and a time horizon of 47 years was used to simulate the lifespan of patients. Setting was Obstetrical clinics in U.S., and Participants were a theoretical cohort of 1,429,074 pregnant patients who annually undergo expanded carrier screening. Results Among our cohort, BRCA1 testing resulted in identification of an additional 3,716 BRCA1 patients, prevention of 1,394 breast and ovarian cancer cases, and 1,084 fewer deaths. BRCA1 testing was a cost-effective strategy compared to no BRCA1 testing with an ICER of $86,001/QALYs. In a one-way sensitivity analysis, we varied the prevalence of BRCA1 in the population from 0% up to 20% and found that BRCA1 testing continued to be the cost-effective strategy until prevalence rate was reduced to 0.16% (Table S1). Multiple additional sensitivity analyses did not substantially impact the cost-effectiveness. Conclusion The addition of BRCA1 testing to obstetrical prenatal carrier screening is a cost-effective management strategy to identify at-risk women at a time when cancer screening and preventive strategies can be effective. Despite the burden of additional genetic counseling, prenatal care represents a unique opportunity to implement population-based genetic testing.