Effect of pamidronate on new vertebral fractures and bone mineral density in patients with malignant lymphoma receiving chemotherapy

BACKGROUND: High doses of corticosteroids, and the use of alkylating agents like cyclophosphamide with subsequent hypogonadism, have been implicated in the pathogenesis of chemotherapy-induced osteoporosis. In this study, we evaluated whether intravenous pamidronate can prevent bone loss and reduce vertebral fractures in patients with malignant lymphoma who were receiving chemotherapy. METHODS: We enrolled 50 patients who had newly diagnosed stage III or IV malignant lymphoma. All patients were assigned randomly to receive either intravenous pamidronate or placebo. Pamidronate (30 mg per treatment) or placebo was given at 3-month intervals for 12 months. Five patients in the control group dropped out during the trial. The main outcomes were the incidence of vertebral fractures and changes in bone mineral density of the lumbar spine and proximal femur. RESULTS: During the 12-month study, 6 (30%) of the 20 patients in the control group and 1 (4%) of the 25 patients in the pamidronate group developed new vertebral fractures (P = 0.01). In the control group, the mean percentage changes in bone mineral density were -11.2% in the lumbar spine and -4.5% in the femoral neck. In contrast, pamidronate treatment led to minor losses of bone mineral density at both sites (-2.7% at the lumbar spine; -2.3% at the femoral neck). The difference between the groups was significant at the lumbar spine (P = 0.005). CONCLUSION: Pamidronate reduces trabecular bone loss and the risk of new vertebral fractures in patients with malignant lymphoma receiving chemotherapy.