Pamidronate reduces skeletal morbidity in women with advanced breast cancer and lytic bone lesions: A randomized, placebo-controlled trial

Purpose: To assess whether pamidronate can reduce the frequency of skeletal morbidity in women with lytic bone metastases from breast cancer treated w ith hormone therapy. Patients and Methods: Three hundred seventy-two women with breast cancer wh o had at least one lytic bone lesion and who were receiving hormonal therap y were randomized to receive 90 mg of pamidronate or placebo as a 2-hour in travenous infusion given in double-blind fashion every 4 weeks for 24 cycle s. patients were evaluated for skeletal complications: pathologic fractures , spinal cord compression, irradiation of or surgery on bone, or hypercalce mia. The skeletal morbidity rate (the ratio of the number of skeletal compl ications to the rime an trial) was the primary efficacy variable. Bone pain , use of analgesics, quality of life, performance status, bone tumor respon se, and biochemical parameters were also evaluated, Results: One hundred eighty-two patients who received pamidronate and 189 w ho received placebo were assessable. The skeletal morbidity rate was signif icantly reduced at 12, 18, and 24 cycles in patients treated with 90 mg of pamidronate (P = .028, .023, and .008, respectively). At 24 cycles, the pro portion of patients having had any skeletal complication was 56% in the pam idronate group and 67% in the placebo group (P = .027), The time to the fir st skeletal complication was longer for patients receiving pamidronate than for those given placebo (P = .049), there was no statistical difference in survival or in objective bone response rate. Pamidronate was well tolerate d, Conclusion: Treatment with 90 mg of pamidronate as a 2-hour intravenous inf usion every 4 weeks in addition to hormonal therapy significantly reduces s keletal morbidity from osteolytic metastases. (C) 1999 by American Society of Clinical Oncology.