Bone loss after oophorectomy among high-risk women: An NRG oncology/gynecologic oncology group study

Objective: Women undergoing premenopausal oophorectomy for a variety of reasons, including to reduce ovarian or breast cancer risk were evaluated for accelerated bone loss. Methods: The Gynecologic Oncology Group (GOG)-0215 randomized phase-II trial of zoledronic acid was initiated to determine if postoophorectomy bisphosphonate therapy could prevent this bone loss. The study was closed after slow accrual prevented evaluation of the primary study endpoint. We analyzed changes in bone mineral density (BMD) among the 80 women randomized to the observation arm of this study, as measured 3, 9, and 18 months postenrollment. Results: The mean change in BMD from baseline to 18 months was-0.09 (95% CI,-0.12 to-0.07),-0.05 (95% CI,-0.07 to-0.03), and-0.06 (95% CI,-0.07 to-0.05) g/cm2 across the lumbar spine, right hip, and left hip, respectively. This represents a BMD decrease of-8.5% for the lumbar spine and-5.7% for both the right and left hips from baseline to 18 months' observation. Conclusions: These results demonstrate that premenopausal women undergoing oophorectomy clearly experience bone loss, an adverse effect of oophorectomy, which requires attention and active management. BMD should be monitored postoophorectomy, and treated per standard practice guidelines. Future studies will be required to determine if early treatment can mitigate fracture risk, and to test promising therapeutic interventions and novel prevention strategies, such as increased physical activity or alternative medications, in randomized trials.