Long-term consequences of ovarian ablation for premenopausal breast cancer

The TEXT and SOFT trials concluded that an aromatase inhibitor (AI) with ovarian ablation (OA) yields a higher 5-year disease-free survival than tamoxifen alone in premenopausal ER+ high-risk early breast cancer. However, the long-term health consequences and costs of OA, either by GnRH agonist or oophorectomy, have not been evaluated. The objective was to conduct a cost-effectiveness analysis comparing tamoxifen to OA with AI. Markov Monte Carlo simulation model estimated the costs and benefits of 3 endocrine strategies: (1) tamoxifen; (2) GnRH agonist with AI (GnRHa-AI); (3) bilateral salpingo-oophorectomy with AI (BSO-AI). Effectiveness was measured in life expectancy gain (years), and costs were averaged over a lifetime (USD 2015). Adverse events and deaths from each strategy were modeled in the United States population over a time horizon of 40 years. For women without prior chemotherapy (low-risk), tamoxifen alone was more effective (18.03 years) and less costly ($1566) than GnRHa-AI (17.66 years, $93,692) or BSO-AI (17.63 years, $25,892). For those with prior chemotherapy (high-risk), BSO-AI was more costly but more effective (16.78 years, $25,368) than tamoxifen alone (16.55 years, $1523) with an ICER of $102,290, while GnRHa-AI yielded an ICER of $443,376. The simulation estimated 787 and 577 deaths attributable to OA among 9320 high-risk women after BSO-AI and GnRHa-AI, respectively. There may be a role for ovarian ablation in premenopausal women with ER+ high-risk early breast cancer; however, this analysis raises concerns about the long-term health consequences of ovarian ablation and the potential effects on overall survival.