Inclusion Criteria

DISEASE CHARACTERISTICS: Diagnosed breast cancer at high risk for disease recurrence with
one of the following requirements: Disease free stage IV breast cancer following
eradication of disease by surgery, radiotherapy, or chemotherapy Stage I, II, or III
breast cancer remaining clinically free of identifiable disease following adjuvant
chemotherapy with 2 consecutively rising CA15.3 (BR2729) or CEA levels at least 2 weeks
apart Elevation of marker levels not needed for stage III disease if adjuvant therapy
completed within past 2 years CEA increase at least 1.5 times upper chronic value in
patients with significant smoking history and chronic CEA elevation less than 15
Recurrence in the ipsilateral axilla following lumpectomy/axillary dissection or modified
radical mastectomy Recurrence in the ipsilateral breast following lumpectomy/axillary
dissection Stage II disease with at least 4 positive axillary lymph nodes and adjuvant
therapy completed within past 2 years Stable stage IV disease on hormonal therapy
Colonoscopy required for isolated CEA elevation Hormone receptor status: Not specified

PATIENT CHARACTERISTICS: Age: 18 and over Menopausal status: Not specified Performance
status: Karnofsky 90-100% Life expectancy: Not specified Hematopoietic: Lymphocyte count
at least 500/mm3 WBC at least 3,000/mm3 Hepatic: Alkaline phosphatase no greater than 1.5
times upper limit of normal (ULN) SGOT no greater than 1.5 times ULN Renal: Creatinine no
greater than 1.5 times ULN Cardiovascular: No New York Heart Association class III or IV
heart disease Other: No immunodeficiency or autoimmune disease No seafood allergies No
other active malignancies except basal cell or squamous cell skin cancer Not pregnant
Negative pregnancy test Fertile patients must use effective barrier contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: At least 6 weeks since prior immunotherapy
Chemotherapy: See Disease Characteristics At least 4 weeks since prior chemotherapy No
concurrent chemotherapy Endocrine therapy: See Disease Characteristics Radiotherapy: See
Disease Characteristics At least 4 weeks since prior radiotherapy No concurrent
radiotherapy Surgery: See Disease Characteristics At least 4 weeks since prior surgery