Management of treatment-related osteoporosis in men with prostate cancer.

Osteoporosis is an important and preventable adverse effect of androgen deprivation therapy for prostate cancer. Androgen deprivation therapy by either bilateral orchiectomies or administration of a gonadotropin-releasing hormone agonist decreases bone mineral density and increases fracture risk. Treatment-related osteoporosis can be prevented by intermittent administration of either intravenous pamidronate or zoledronic acid. Pamidronate (60 mg intravenously every 3 months) prevents bone loss during androgen deprivation therapy. Zoledronic acid (4 mg intravenously every 3 months) not only prevents bone loss but also increases bone mineral density. Alendronate and other oral bisphosphonates may be effective but have not been evaluated in men with castrate testosterone levels. Oestrogen replacement therapy and treatment with selective ooestrogen receptor modulators may prevent bone loss during androgen deprivation therapy. Bicalutamide (150 mg daily) monotherapy increases serum ooestrogen levels and maintains bone mineral density.