DISEASE CHARACTERISTICS:

• Histologically confirmed metastatic adenocarcinoma of the breast
• HER2 nonoverexpressed (0-1+) OR overexpressed (2-3+)

• Measurable or evaluable disease

  • Pleural or peritoneal effusions allowed if local intracavitary treatment not started at onset of therapy
  • Blastic or mixed blastic/lytic osseous metastases allowed if accompanied by pain or decreased performance status, and do not require radiotherapy within two courses of study therapy
  • Osteolytic disease allowed if proven by x-ray
  • No abnormal bone scan without confirmatory x-rays as only evidence of metastatic disease
• Prior brain metastases responsive to treatment of radiotherapy and/or surgery allowed (cannot be only site of metastases)

• Hormone receptor status:

  • Not specified

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Sex:

• Female

Menopausal status:

• Not specified

Performance status:

• ECOG 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Granulocyte count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3

Hepatic:

• SGOT no greater than 2.5 times upper limit of normal
• Bilirubin normal

Renal:

• Creatinine no greater than 1.5 mg/dL

Cardiovascular:

• No prior deep venous thrombosis or thromboembolic condition
• LVEF at least lower limit of normal
• No prior myocardial infarction or congestive heart failure
• No arrhythmia requiring medication
• No hypertension or systolic or diastolic dysfunction
• No ventricular hypertrophy or conduction abnormality

Pulmonary:

• No prior pulmonary thromboembolism

Other:

• No other malignancy within the past 5 years except curatively treated carcinoma in situ of the cervix or basal cell or squamous cell carcinoma of the skin
• Not pregnant or nursing
• Fertile women must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior trastuzumab (Herceptin™)

Chemotherapy:

• No prior chemotherapy for advanced or local/regional recurrent disease
• Prior adjuvant chemotherapy allowed if completed 6 months before metastasis
• No prior anthracyclines or anthracenediones

Endocrine therapy:

• At least 2 weeks since prior hormonal therapy

Radiotherapy:

• Prior radiotherapy allowed only to conserved breast, postmastectomy chest wall with or without internal mammary lymph node chain (IMN), or field containing less than 25% bone marrow
• No prior photon IMN treatment
• At least 2 weeks since prior radiotherapy
• No concurrent radiotherapy

Surgery:

• At least 2 weeks since surgery (including mastectomy) and recovered