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

DISEASE CHARACTERISTICS: * Histologically proven breast cancer * Metastatic disease * Previous relapsed disease in sites other than bone allowed * Newly diagnosed multiple bone metastases within the past 3 months, meeting all of the following criteria: * Painful or asymptomatic * Lytic, mixed, or purely sclerotic type * Radiological diagnosis * IV bisphosphonate therapy indicated * No CNS metastases * Hormone receptor status not specified PATIENT CHARACTERISTICS: * ECOG performance status 0-2 * Male or female * Menopausal status not specified * No known active peptic ulcer * Not pregnant or nursing * Fertile patients must use effective contraception * No active dental problems, including infection of the teeth or jawbone (maxilla or mandible) or dental or fixture trauma * No prior or current diagnosis of osteonecrosis of the jaw, exposed bone in the mouth, or slow healing after dental procedures * Creatinine clearance ≥ 30 mL/min * Bilirubin ≤ 1.5 x upper limit of normal (ULN) * AST and ALT ≤ 1.5 times ULN * No history of bisphosphonate hypersensitivity * Able to comply with instructions relating to oral study medications * Able to take oral study medications * No psychiatric illness or other condition that would preclude giving informed consent PRIOR CONCURRENT THERAPY: * At least 6 months since prior bisphosphonate therapy * At least 6 weeks since prior and no concurrent dental or jaw surgery (e.g., extractions or implants) * Concurrent unplanned denta…