Aromatase inhibitor-associated bone loss.

273 A 49-year-old postmenopausal Caucasian woman named M.A. was diagnosed with estrogen receptor (ER)-positive, progesterone receptor (PR)-positive, HER2-negative breast cancer. Anthracycline and taxane-based adjuvant chemotherapy and radiation therapy were followed by adjuvant therapy with an aromatase inhibitor (AI). Before M.A. started adjuvant AI therapy, she was evaluated for any additional risks for bone loss or fractures. Her bone mineral density was measured by dual-energy x-ray absorptiometry of the lumbar spine and hip; follow-up bone evaluations were scheduled at 6, 12, and 24 months. M.A.’s age at the onset of menopause was 43, and she reported a family history of early menopause and osteoporosis with fragile hip fracture. Considering M.A.’s early age of menopausal onset, baseline bone mineral density, and family history, the medical oncologist offered her the opportunity to participate in a clinical trial in which patients were randomized to receive an AI with or without concurrent bisphosphonate treatment. M.A. chose to participate in the trial (National Cancer Institute, Naples, 2010) and, after providing informed consent, was randomized to the study arm that included the addition of zoledronic acid therapy (4 mg via IV every six months) to letrozole (2.5 mg orally daily) for a planned duration of five years. �herapy was initiated after a dental examination to assess risk factors for osteonecrosis of the jaw, which yielded no pathology. �he potential side effects of letrozole and zoledronic acid were discussed with M.A. She was advised to continue taking oral calcium (1 g per day) and vitamin D (400 IU daily) supplementation. �he importance of adding a regular weight training exercise program, maintaining proper nutrition, and adhering to the treatment regimen also were reviewed with M.A. Following six months of therapy, M.A. began an exercise program that included a weight-resistance training regimen. M.A. Aromatase Inhibitor-Associated Bone Loss