Decision analysis of prophylactic mastectomy and oophorectomy in BRCA1- positive or BRCA2-positive patients

Purpose: Young Ashkenazi Jewish women or those from high-risk families who test positive for BRCA1 or BRCA2 mutant genes have a significant risk of developing breast or ovarian cancer by the age of 70 years. Many question whether they should have prophylactic surgical procedures, ie, bilateral mastectomy and/or oophorectomy. Methods: A Markov model was developed to determine the survival, quality of life, and cost-effectiveness of prophylactic surgical procedures. The probabilities of developing breast and ovarian cancer were based on literature review among women with the BRCA1 or BRCA2 gene and mortality rates were determined from Surveillance, Epidemiology, and End Results (SEER) data for 1973 to 1992. The costs for hospital and ambulatory care were estimated from Health Care Financing Administration (HCFA) payments in 1995, supplemented by managed care and fee- for-service data. Utility measures for quality-adjusted life-years (QALYs) were explicity determined using the time-trade off method. Estimated risks for breast and ovarian cancer after prophylactic surgeries were obtained from the literature. Results: For a 30-year-old woman, according to her cancer risks, prophylactic oophorectomy improved survival by 0.4 to 2.6 years; mastectomy, by 2.8 to 3.4 years; and mastectomy and oophorectomy, by 3.3 to 6.0 years over surveillance. The QALYs saved were 0.5 for oophorectomy and 1.9 for the combined procedures in the high-risk model. Prophylactic surgeries were cost-effective compared with surveillance for years of life saved, but not for QALYs. Conclusion: Among women who test positive for o BRCA1 or BRCA2 gene mutation, prophylactic surgery at a young age substantially improves survival, but unless genetic risk of cancer is high, provides no benefit for quality of life. Prophylactic surgery is cost- effective for years of life saved compared with other medical interventions that are deemed cost-effective.