Inclusion Criteria:

- Histologically confirmed adenocarcinoma of the female breast which is inoperable,
recurrent or metastatic

- HER-2/neu status must be known at the time of protocol registration; HER-2/neu
assessment will be based on FISH analysis of either the primary tumor or a metastatic
site; a scoring of 0 or 1+ by immunohistochemistry (IHC) is considered negative; 2+
is considered negative unless confirmed by FISH positivity, in which case it should
be considered positive; 3+ by IHC is considered positive; for centers using FISH
only, a positive FISH assay by itself is sufficient to determine HER-2 positivity

- Patients with the following prior therapy are eligible:

- Patients with 0-1 prior chemotherapy regimens for metastatic or locally advanced
breast cancer, with the following exception: no prior taxane for
metastatic/locally advanced breast cancer

- Patients with 0-1 prior chemotherapy regimens in the adjuvant setting; if
adjuvant regimen included a taxane, patient must have been disease free for at
least 12 months from completion of adjuvant therapy until relapse

- Patients must be > 2 weeks from prior surgery, other than simple biopsy or
placement of venous access device; patients must be > 4 weeks from prior
chemotherapy; patients must be >6 weeks from nitrosoureas, melphalan, or
mitomycin

- Patients must be > 4 weeks from prior hormonal therapy unless tumor
measurements document clear progression while on treatment; if progression
is documented and toxicity from hormonal regimen has resolved, patients may
be placed on study > 1 week from prior hormonal therapy

- Prior Herceptin therapy is not allowed

- Patients with central nervous system metastases are eligible only if the patient has
completed cranial irradiation at least 6 months prior, is currently asymptomatic, and
is not currently receiving corticosteroids for this condition; patients with
leptomeningeal carcinoma (carcinomatous meningitis) are not eligible

- MESURABLE DISEASE: Any mass reproducibly measurable in two perpendicular dimensions,
examples include:

- Pulmonary nodules

- Hepatic lesions

- Skin nodules (if two measurements can be assigned)

- Lymph nodes

- The following lesions do not qualify as measurable:

- Central nervous system (CNS) lesions

- Bone disease only; lytic lesions should be documented and followed

- Lymphangitic pulmonary metastases (patients with lymphangitic metastases are
eligible if there are other sites of metastatic disease which can be measured)

- Lesions which have been irradiated unless there is definite documentation of
progression since radiotherapy

- A baseline assessment of left ventricular ejection fraction within 8 weeks of
registration is required (echocardiogram or resting multi gated acquisition scan
[MUGA] (radionuclide cineangiography [RNCA]) nuclear scintigraphy); patients with a
left ventricular ejection fraction (LVEF) < 45% are ineligible

- Granulocytes >= 1500/ul

- Platelet count >= 100,000/ul

- Creatinine =< 2.0 mg/dl

- Bilirubin within institutional normal limits

- Serum glutamic oxaloacetic transaminase (SGOT) (aspartate aminotransferase [AST])