Combination Chemotherapy With Trastuzumab in Treating Women With Metastatic Breast Cancer

You may be eligible if

• DISEASE CHARACTERISTICS:
• Histologically confirmed metastatic breast cancer c-erbB2 positive (3+ overexpression by the HercepTest™ method) in the primary tumor or metastatic site
• At least 1 unidimensionally measurable target lesion
• * At least 20 mm by conventional techniques OR
• * At least 10 mm by spiral CT scan
• * Lesions that have been irradiated in the preceding 3 months cannot be used as target lesions unless they have appeared or clearly progressed since prior irradiation
• * No bone lesions as the only target lesions
• No contralateral breast cancer that is c-erbB2-positive or c-erbB2-negative/unknown, with status determined on a metastatic site
• No CNS metastases
• * CT scan of brain and CSF cytology are required if neurologic symptoms are present
• Hormone receptor status:
• * Any estrogen or progesterone receptor status
• PATIENT CHARACTERISTICS:
• Age:
• 18 and over
• Sex:
• Female
• Menopausal status:
• Any status
• Performance status:
• ECOG 0-2
• Life expectancy:
• Not specified
• Hematopoietic:
• Neutrophil count at least 1,500/mm\^3
• Platelet count at least 100,000/mm\^3
• Hepatic:
• Bilirubin no greater than 1.25 times upper limit of normal (ULN)
• Transaminases less than 2.5 times ULN (5 times ULN if liver metastases present)
• Renal:
• For patients age 18 to 69:
• * Creatinine no greater than ULN
• For patients age 70 and over:
• * Creatinine clearance normal
• Cardiovascular:
• LVEF normal by MUGA or echocardiogram
• No clinical heart failure
• Pulmonary:
• No malignancy-associated dyspnea at rest
• No requirement for supportive oxygen therapy
• Other:
• Not pregnant or nursing
• No other prior or concurrent malignancy within the past 5 years except adequately treated carcinoma in situ of the cervix or basal cell skin cancer
• No psychological, familial, sociological, or geographical condition that would preclude compliance with study therapy and follow-up schedule
• PRIOR CONCURRENT THERAPY:
• Biologic therapy:
• No prior anti-c-erbB2 antibody, including trastuzumab (Herceptin®)
• No other concurrent biologic therapy
• Chemotherapy:
• No more than 1 prior chemotherapy regimen for metastatic breast cancer
• Prior combination of cyclophosphamide, methotrexate, and fluorouracil (CMF) allowed in the adjuvant or metastatic setting only if the disease-free interval after completion of CMF was at least 12 months
• Prior anthracyclines and/or taxanes allowed
• At least 4 weeks since prior anthracyclines
• No prior cumulative dose of doxorubicin more than 360 mg/m\^2
• No prior cumulative dose of epirubicin more than 720 mg/m\^2
• No prior cumulative dose of mitoxantrone more than 90 mg/m\^2
• No other concurrent chemotherapy
• Endocrine therapy:
• More than 2 weeks since prior hormonal therapy in the adjuvant or metastatic setting
• No concurrent hormonal therapy
• Radiotherapy:
• See Disease Characteristics
• No concurrent radiotherapy
• Surgery:
• Not specified
• Other:
• No other concurrent anticancer therapy or investigational drugs
• No concurrent bisphosphonates started after study enrollment except for hypercalcemia