Current use of bisphosphonates in oncology. International Bone and Cancer Study Group.

The purpose of this article is to review the recent data on bisphosphonate use in oncology and to provide some guidelines on the indications for their use in cancer patients. The group consensus reached by experts on the rationale for the use of bisphosphonates in cancer patients and their current indications for the treatment of tumor-induced hypercalcemia and metastatic bone pain in advanced disease and for the prevention of the complications of multiple myeloma and of metastatic bone disease are reviewed. Bisphosphonates are potent inhibitors of tumor-induced osteoclast-mediated bone resorption. They now constitute the standard treatment for cancer hypercalcemia, for which we recommend a dose of 1,500 mg of clodronate or 90 mg of pamidronate; the latter compound is more potent and has a longer lasting effect. Intravenous bisphosphonates exert clinically relevant analgesic effects in patients with metastatic bone pain. Regular pamidronate infusions can also achieve a partial objective response by conventional International Union Against Cancer criteria and enhance the objective response rate to chemotherapy. In breast cancer, the prolonged administration of oral clodronate 1,600 mg daily reduces the frequency of morbid skeletal events by more than one fourth, whereas monthly pamidronate infusions of 90 mg for only 1 year in addition to chemotherapy reduce by more than one third the frequency of all skeletal-related events. The use of bisphosphonates to prevent bone metastases remains experimental. Last, bisphosphonates in addition to chemotherapy are superior to chemotherapy alone in patients with stages II and III multiple myeloma and can reduce the skeletal morbidity rate by approximately one half. Bisphosphonate use is a major therapeutic advance in the management of the skeletal morbidity caused by metastatic breast cancer or multiple myeloma, although many questions remain unanswered, notably regarding the optimal selection of patients and the duration of treatment.