DISEASE CHARACTERISTICS:

• Histologically confirmed metastatic or recurrent breast carcinoma

  • Unresectable disease
  • Previously treated with no more than 2 chemotherapy regimens for metastatic disease OR
  • Recurrent within 6 months of adjuvant chemotherapy

• Must have one of the following:

  • Measurable disease

  • Positive bone scan and elevation of serum tumor marker for adenocarcinoma

    • Serum levels must have increased over 2 consecutive measurements and exceed at least 2 times upper limit of normal
• Lewis-y antigen expression documented by immunohistochemistry
• No brain metastases that are uncontrolled or require active treatment (including steroids)

• Hormone receptor status:

  • Not specified

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Sex:

• Female

Menopausal status:

• Not specified

Performance status:

• ECOG 0-2

Life expectancy:

• At least 3 months

Hematopoietic:

• Hemoglobin at least 10 g/dL
• Absolute neutrophil count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3
• No bleeding diathesis

Hepatic:

• Bilirubin no greater than 1.5 mg/dL
• SGOT no greater than 2.5 times normal
• Alkaline phosphatase no greater than 2.5 times normal (unless documented bony metastasis present)
• Amylase/lipase less than 1.5 times normal
• Hepatitis B and C negative
• No hepatic failure

Renal:

• Creatinine no greater than 1.5 times upper limit of normal
• No renal failure

Cardiovascular:

• LVEF greater than 50% by echocardiogram or MUGA scan
• No congestive heart failure

Other:

• HIV negative
• No antibody present that detects monoclonal antibody BR96 in serum
• No peripheral neuropathy grade 2 or greater
• No dementia or altered mental status
• No other serious underlying medical condition that would preclude study participation
• No prior allergic reactions to recombinant human or murine proteins
• No uncontrolled peptic ulcer disease
• No active viral, bacterial, or systemic fungal infections
• No other primary malignancy except nonmelanoma skin cancer or carcinoma in situ of the cervix
• No serious nonmalignant disease
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• At least 8 weeks since prior therapeutic or diagnostic murine/humanized/human chimeric antibodies

Chemotherapy:

• See Disease Characteristics
• At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas, carboplatin, mitomycin, or anthracyclines)
• No prior cumulative anthracycline of 300 mg/m2 or more
• No concurrent antineoplastic agents

Endocrine therapy:

• See Disease Characteristics
• At least 4 weeks since prior hormonal therapy
• No concurrent hormonal therapy except estrogen replacement

Radiotherapy:

• At least 4 weeks since prior radiotherapy

Surgery:

• See Disease Characteristics

Other:

• No other concurrent experimental agents
• No concurrent immunosuppressive medications