DISEASE CHARACTERISTICS:

• Diagnosis of stage IV breast cancer
• Failed at least 1 prior conventional therapy for metastatic disease

• Measurable or evaluable disease by clinical, radiographic, or laboratory assessment

  • Measurable lesions must be at least 1 dimension

    • At least 20 mm by conventional techniques OR at least 10 mm by spiral CT scan

  • The following are not considered measurable:

    • Pleural effusion
    • Bone lesions
    • Tumor markers
• HLA-A2-expressing disease by human leukocyte antigen typing

• No CNS metastases by contrast CT scan and/or MRI

  • No brain metastases within the past 4 years

• Hormone receptor status:

  • Not specified

PATIENT CHARACTERISTICS:

Age

• 18 and over

Sex

• Not specified

Menopausal status

• Not specified

Performance status

• ECOG 0-1

Life expectancy

• More than 6 months

Hematopoietic

• WBC ≥ 3,000/mm^3
• Platelet count ≥ 75,000/mm^3
• Hemoglobin ≥ 10 g/dL

Hepatic

• Bilirubin ≤ 1.5 times upper limit of normal (ULN)
• ALT and AST ≤ 2.5 times ULN
• Hepatitis B negative
• Hepatitis C negative

Renal

• Creatinine ≤ 1.5 times ULN

Immunologic

• HIV negative
• Human T-cell lymphotrophic virus-1 negative
• No active infection
• No major autoimmune disorder that would preclude study participation

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception during and for 6 months after study participation
• No alcohol abuse or illicit drug use within the past 12 months
• No clinically significant comorbid disease or other underlying condition that would preclude study participation
• No significant psychiatric disorder that would preclude giving informed consent or complying with study

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior allogeneic or autologous bone marrow or stem cell transplantation
• More than 30 days since prior hematopoietic growth factors
• More than 30 days since initiation of prior immunotherapy (e.g., trastuzumab [Herceptin])
• Concurrent immunotherapy (e.g., trastuzumab) allowed provided regimen was initiated more than 30 days before study entry, disease is stable or progressive, and patient plans to continue immunotherapy for the duration of study participation
• No other concurrent hematopoietic growth factors

Chemotherapy

• More than 30 days since prior chemotherapy
• No concurrent chemotherapy

Endocrine therapy

• More than 30 days since prior glucocorticoids
• More than 30 days since initiation of prior hormonal therapy (e.g., tamoxifen, anastrozole, or letrozole)
• Concurrent hormonal therapy (e.g., tamoxifen, anastrozole, or letrozole) allowed provided regimen was initiated more than 30 days before study entry, disease is stable or progressive, and patient plans to continue hormonal therapy for the duration of study participation
• No concurrent glucocorticoids

Radiotherapy

• More than 30 days since prior radiotherapy
• No concurrent radiotherapy

Surgery

• Not specified

Other

• More than 14 days since prior anticoagulants (e.g., warfarin, heparin, or enoxaparin)

  • Low-dose anticoagulants to maintain IV catheter patency allowed
• More than 30 days since prior immunosuppressive drugs
• More than 30 days since prior experimental therapy
• No concurrent immunosuppressive drugs
• No other concurrent investigational products