A total of 295 patients with lytic bone
metastases from
breast cancer were randomized to receive
chemotherapy or
chemotherapy plus
pamidronate (
Aredia) 45 mg intravenously every 3 weeks. Primary endpoints were time to progressive
bone disease (evaluated by blind extramural review), and improvement in
pain (according to a 6-point self-assessment scale). Secondary endpoints included incidence of bone-related complications (
pathological fractures,
tumor-induced
hypercalcemia, need for
radiotherapy), sclerotic response of lytic lesions, WHO performance status, and
analgesic score. Median time to bone progression was 249 days and 168 days in the
pamidronate and control groups respectively (p = 0.02). Marked improvement in bone
pain was observed in 44% of patients receiving
pamidronate compared to 30% in controls (p = 0.025). With respect to secondary endpoints,
pamidronate reduced the need for
radiotherapy (66 times vs. 82 times in controls), and median time to
radiotherapy was 697 days with
pamidronate, 571 in the control arm. No severe adverse reactions or worsening of
chemotherapy-induced toxicities were observed during 1598
pamidronate infusions. We conclude that intravenous
pamidronate is well tolerated, significantly prolongs time to progressive
bone disease, and significantly improves bone
pain in patients with osteolytic
metastases from
breast cancer.