Efficacy of Denosumab in Managing BMD Loss in Breast Cancer Patients Treated with Aromatase Inhibitors

Background : Aromatase inhibitors (AIs) are associated with accelerated bone mineral density (BMD) loss and an increased risk of osteoporosis.Denosumab (Prolia ) has demonstrated efficacy in improving BMD and preventing fractures in patients with hormone receptor-positive (HR+) breast cancer.However, data on its effectiveness in Korean populations remain limited.This retrospective observational study aimed to evaluate prescription patterns and effectiveness of denosumab in managing AI-induced BMD loss in patients with HR+ breast cancer at a single tertiary hospital in Korea. Methods :Retrospective data of HR+ breast cancer patients diagnosed with osteoporosis and first prescribed denosumab between November 2016 and June 2021 while receiving AIs were collected.Data of patients who were followed up to June 2024 included prescription records, BMD assessment, bone turnover marker measurements, fracture history, and adverse events. Results :Baseline T-scores for the lumbar spine, femoral neck, and total hip were -2.2, -1.9, and -1.2, respectively.At 12 months (n=35), 24 months (n=51), and 36 months (n=17), T-scores increased by 23.15%, 33.96% and 33.88% for the lumbar spine; 9.31%, 20.38% and 23.35% for the femoral neck; and 25.70%, 64.03%, and 73.80% for the total hip, respectively.Regarding bone turnover markers, serum CTx and P1NP levels were