Role of pamidronate in the management of bone metastases from breast cancer: Results of a non-comparative multicenter phase II trial

Bone metastases are a common cause of morbidity in patients with breast cancer. In an open, phase II, non-comparative trial to investigate the effects of repeated infusions of pamidronate (Aredia®) on pain, mobility, analgesic consumption, bone healing and bone metabolism, 69 patients with breast cancer and bone metastases received pamidronate 60 mg intravenously in 250 ml normal saline over 1 or 4 hours every 2 weeks for a total of 13 infusions, until either progressive disease or a serious adverse event. Improvement in pain score was seen in 33 of 54 evaluable patients (61%) as measured by a linear analogue pain scale, and in 28 of 56 evaluable patients (50%) as measured on a 6-point pain scale: 18 (30%) of 60 evaluable patients showed reduction in a 6-point analgesic score, while 28 patients (50%) showed some improvement in mobility, as assessed by a questionnaire. Sclerosis appeared in > 25% of bone lesions in 2 patients and in < 25% of bone lesions in 12 patients. Urinary calcium/creatinine ratios fell dramatically during therapy. One patient developed symptomatic hypocalcemia, 1 showed deterioration in pre-existing renal insufficiency. Fever occurred in 19% of patients, and less than 20% developed nu-like symptoms. We conclude that intravenous infusions of pamidronate at a dose of 60 mg every 2 weeks produces a marked reduction in pain in patients with extensive bone metastases from breast cancer.