Suppression of bone density loss and bone turnover in patients with hormone-sensitive prostate cancer and receiving zoledronic acid.

OBJECTIVE: To report a randomized, placebo-controlled study of treatment with zoledronic acid every 3 months in patients with hormone-sensitive prostate cancer, both with and without bone metastases, to assess the effect on bone mineral density (BMD) and markers of bone turnover.

PATIENTS AND METHODS: Eligible patients included those with prostate cancer and on androgen-deprivation therapy for <12 months. Patients received zoledronic acid 4 mg intravenously, or placebo, every 3 months for four treatments. BMD, urinary N-telopeptides of type I collagen (NTX), and serum bone alkaline phosphatase (BAP) were measured every 3 months. In all, 42 patients were randomized.

RESULTS: After excluding BMD data from sites of known metastases, patients receiving zoledronic acid had a relative increase in BMD compared with those receiving placebo, of 4.2% and 7.1% at the femoral neck and lumbar spine, respectively. NTX and BAP decreased significantly in patients receiving zoledronic acid. NTX and BAP levels were significantly higher at baseline in patients with bone metastases than in those without.

CONCLUSIONS: Treatment with zoledronic acid every 3 months preserved bone density and suppressed markers of bone turnover in patients with androgen-deprived prostate cancer, both with and without bone metastases.