Bisphosphonate treatment of bone metastases and hypercalcemia of malignancy

Bone metastases and hypercalcemia are common in patients with advanced cancer and may present major problems for physicians treating these patients. The recent development of the bisphosphonates has improved therapy for these two conditions. These compounds, pyrophosphate analogs with a P-C-P backbone, which binds tightly to calcified bone matrix, include etidronate, clodronate, and pamidronate. All three are useful for the treatment of hypercalcemia, but pamidronate seems to be the most effective. Currently investigational in the United States, pamidronate is now in active clinical testing. The author discusses the administration, dosage and side effects, and results of current studies.