Inclusion Criteria

DISEASE CHARACTERISTICS: Diagnosis of locally advanced or metastatic breast cancer High
likelihood of anthracycline resistance due to prior anthracycline exposure in the adjuvant
or metastatic setting Prior anthraquinone (e.g., mitoxantrone) insufficient Prior
cumulative anthracycline dose limited to doxorubicin-equivalent 350 mg/m2 by IV bolus or
450 mg/m2 by prolonged (at least 48 hours) infusion Measurable or evaluable disease Brain
metastases treated by prior surgery and/or radiotherapy allowed if neurologic status
stable 2 weeks after discontinuation of dexamethasone Hormone receptor status: Not
specified

PATIENT CHARACTERISTICS: Age: 18 and over Sex: Male or female Menopausal status: Not
specified Performance status: Zubrod 0-2 Life expectancy: At least 12 weeks Hematopoietic:
Absolute granulocyte count greater than 1,500/mm3 Platelet count greater than 100,000/mm3
Hepatic: Bilirubin no greater than 1.5 mg/dL Renal: Creatinine no greater than 1.5 mg/dL
Cardiovascular: No history of heart failure Ejection fraction at least 55% by
2-dimensional echocardiogram Other: Not pregnant or nursing Negative pregnancy test
Fertile patients must use effective contraception Other prior malignancy allowed if
curatively treated and there is clear diagnosis of metastatic breast cancer requiring
treatment

PRIOR CONCURRENT THERAPY: Biologic therapy: No concurrent prophylactic filgrastim (G-CSF)
Chemotherapy: See Disease Characteristics At least 3 weeks since prior chemotherapy (6
weeks for mitomycin or nitrosourea) and recovered Endocrine therapy: See Disease
Characteristics Radiotherapy: See Disease Characteristics At least 3 weeks since prior
radiotherapy and recovered Surgery: See Disease Characteristics