Liposomal Doxorubicin Compared With Observation or Cyclophosphamide and Methotrexate in Treating Older Women Who Have Undergone Surgery for Breast Cancer (CASA)

DISEASE CHARACTERISTICS: Histologically confirmed breast cancer Disease must be confined to the breast and axillary nodes without detected masses elsewhere No history of prior ipsilateral or contralateral invasive breast cancer Resected disease No more than 16 weeks since last surgery to remove the tumor No known clinical residual locoregional disease Margins must be negative for invasive breast cancer and ductal carcinoma in situ No locally advanced, inoperable breast cancer including any of the following: Inflammatory breast cancer Supraclavicular node involvement Enlarged internal mammary nodes unless pathologically negative Synchronous bilateral invasive breast cancer (diagnosed in the past 2 months) allowed if all tumors are hormone receptor-negative Must not be a candidate for endocrine therapy or standard chemotherapy Hormone receptor-negative disease PATIENT CHARACTERISTICS: Female Menopausal status: postmenopausal ECOG performance status 0-2 Platelet count ≥ 100,000/mm^3 Granulocyte count ≥ 1,500/mm^3 WBC ≥ 3,000/mm^3 AST and ALT ≤ 1.5 times upper limit of normal (ULN) Bilirubin normal Creatinine clearance ≥ 50 mL/min Creatinine < 1.35 mg/dL No significant malabsorption syndrome or disease affecting gastrointestinal tract function No myocardial infarction within the past 6 months No pulmonary embolism within the past 6 months No deep vein thrombosis within the past 6 months No New York Heart Association class III or IV heart disease LVEF ≥ 50% by echocardiography, radionucleotide ventriculography, or MUGA No evidence of acute ischemia by ECG No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix or bladder, or ipsilateral or contralateral breast carcinoma in situ No active, uncontrolled infection No active hepatitis B or C virus infection No other chronic infection Patients must not have any of the following "geriatric syndromes": Dementia Delirium Major depression (as diagnosed by a psychiatrist) Recent falls Spontaneous bone fractures Neglect Abuse No evidence of medically relevant conduction system abnormalities that would preclude study entry No other nonmalignant, uncontrolled systemic diseases, psychiatric illness, or addictive or cognitive disorder that would preclude study participation or compliance PRIOR CONCURRENT THERAPY: At least 4 weeks since prior raloxifene, tamoxifen citrate, or other selective estrogen receptor modulators (SERMs) No concurrent recombinant human epoetin alfa or pegfilgrastim No prior neoadjuvant or adjuvant therapy for breast cancer except radiotherapy Concurrent trastuzumab (Herceptin®) allowed No concurrent hormonal replacement therapy No other concurrent hormonal therapy (including estrogen, progesterone, androgens, tamoxifen citrate, SERMs, or aromatase inhibitors) except for the following: Steroids for adrenal failure Hormones for non-disease-related conditions (e.g., insulin for diabetes) Intermittent dexamethasone as an antiemetic No other concurrent investigational agents No concurrent bisphosphonates, except for the treatment of osteoporosis For patients who received prior anthracyclines, the following criteria must be met: Cumulative dose ≤ 240 mg/m² for conventional doxorubicin ≤ 140 mg/m² in case of prior doxorubicin and left chest radiotherapy (LCRT) Cumulative dose ≤ 400 mg/m² for epirubicin ≤ 230 mg/m² in case of prior epirubicin and LCRT