Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed stage IV breast cancer meeting 1 of the following criteria:

- No evidence of disease

- Stable disease on hormonal therapy

- Stable disease must be present for ≥ 2 months and include < 30% decrease or
< 20% increase in the sum of the longest diameter of target lesion

- No new target lesions or unequivocal progression of non-target lesions

- Elevation in the CA 153 (BR2729) or CEA values allowed

- Hormone receptor status not specified

PATIENT CHARACTERISTICS:

- Female or male

- Menopausal status not specified

- Karnofsky performance status 80-100%

- Lymphocyte count ≥ 500/mm³

- WBC ≥ 3,000/mm³

- Creatinine ≤ 1.5 times upper limit of normal (ULN)

- AST ≤ 1.5 times ULN

- Alkaline phosphatase ≤ 1.5 times ULN

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No history of allergy to seafood

- No NYHA class III-IV cardiac disease

- No other active cancers except basal cell or squamous cell carcinoma of the skin

- No active infection requiring antibiotic treatment

- No known history of immunodeficiency or autoimmune disease

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- At least 4 weeks since prior chemotherapy

- At least 4 weeks since prior radiotherapy

- At least 4 weeks since prior surgery

- At least 6 weeks since prior immunotherapy

- No prior sialyl Lewisª antigen

- No concurrent immunosuppressive medications (i.e., corticosteroids)

- Concurrent hormonal therapy allowed