Ibandronate or Zoledronate in Treating Patients With Newly Diagnosed Bone Metastases From Breast Cancer

OBJECTIVES: Primary * Compare the efficacy, in terms of reducing frequency and timing of skeletal-related events (SREs), of ibandronate vs zoledronate in patients with newly diagnosed bone metastases secondary to breast cancer. Secondary * Compare the median time to first SRE in patients treated with these regimens. * Compare the percentage of patients experiencing a SRE after treatment with these regimens. * Compare the number of occult vertebral fractures present in patients at the end of treatment with these regimens. * Compare the pain and analgesic scores and quality of life of patients treated with these regimens. * Compare the number of patients developing renal dysfunction or hypocalcemia during the study period. * Compare the number of patients developing osteonecrosis of the jaw during study treatment and follow-up. * Compare the overall survival of these patients at 96 weeks and at 5 years. * Compare the health-resource usage of patients treated with these regimens. OUTLINE: This is a randomized, open-label, parallel-group, controlled, multicenter study. Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients receive zoledronate IV over 15 minutes on day 1. Treatment repeats every 21\* or 28 days for at least 96 weeks (24 or 32 courses) in the absence of disease progression or unacceptable toxicity. NOTE: \*Patients who receive concurrent chemotherapy every 3 weeks receive study treatment every 21 days * Arm II: Patients receive oral ibandronate once daily on days 1-28. Treatment repeats every 28 days for at least 96 weeks (24 courses) in the absence of disease progression or unacceptable toxicity. Patients with bone pain or hypercalcemia at study entry or those who require IV therapy due to hypercalcemia while on study may receive 1 treatment with ibandronate IV at the discretion of the supervising clinician. Quality of life and pain are assessed at baseline, after every 3 courses, and at completion of study treatment. After completion of study treatment, patients are followed annually for up to 3 years. PROJECTED ACCRUAL: A total of 1,400 patients will be accrued for this study.