Doxorubicin Hydrochloride Liposome as First-Line Therapy in Treating Older Women With Metastatic Breast Cancer

DISEASE CHARACTERISTICS: * Histologically confirmed invasive ductal or lobular adenocarcinoma of the breast * Metastatic disease as confirmed by ≥ 1 of the following: * Histology or cytology * Radiology * Elevated CA 15-3 levels * No HER2/neu overexpression by IHC or FISH * Measurable (≥ 10 mm) or evaluable disease * Bone lesions or isolated pleural effusion allowed * Hormone receptor status not specified PATIENT CHARACTERISTICS: * Postmenopausal * Life expectancy \> 3 months * ANC ≥ 1,500/mm\^3 * Platelet count ≥ 100,000/mm\^3 * Hemoglobin ≥ 9 g/dL * AST and ALT ≤ 2.5 times upper limit of normal (ULN) (5 times ULN if liver metastases are present) * Alkaline phosphatase ≤ 5 times ULN * Bilirubin ≤ 2 times ULN * Creatinine clearance ≥ 30 mL/min * LVEF ≥ 50% * No congestive heart failure or other uncontrolled cardiac disease * No other malignancy within the past 5 years except for curatively treated carcinoma in situ of the cervix, urothelial in situ carcinoma, or basal cell cancer * No prior hypersensitivity to anthracyclines * No psychological, familial, social, or geographical reason that would preclude study follow-up * No serious illness or physical or mental condition resulting in a permanent disability that may preclude successful treatment PRIOR CONCURRENT THERAPY: * No prior chemotherapy for metastatic disease * Prior adjuvant chemotherapy allowed * No development of metastatic disease within 6 months after completion of adjuvant anthracycline-based chemotherapy * No more than 300 mg/m² of prior doxorubicin hydrochloride or 600 mg/m² of prior epirubicin hydrochloride in the adjuvant setting * More than 30 days since prior participation in another clinical trial