DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the breast

  • Metastatic disease
• Previously treated with chemotherapy in the adjuvant setting and/or for metastatic disease

• At least one unidimensionally measurable lesion

  • At least 20 mm by CT scan or MRI OR at least 10 mm by spiral CT scan
  • Superficial clinical lesions (e.g., skin nodules or palpable lymph nodes) are allowed
  • Lesions on chest x-ray are allowed provided they are clearly defined and surrounded by aerated lung

  • The following are not considered measurable:

    • Bone lesions
    • Ascites
    • Leptomeningeal disease
    • Pleural/pericardial effusion
    • Inflammatory breast disease
    • Lymphangitis cutis/pulmonis
    • Cystic lesions
• No known CNS metastases unless controlled by prior surgery and/or radiotherapy

• Hormone receptor status:

  • Estrogen receptor (ER) and/or progesterone receptor (PR) status known

PATIENT CHARACTERISTICS:

Age

• 18 and over

Sex

• Male or female

Menopausal status

• Not specified

Performance status

• ECOG 0-2

Life expectancy

• At least 3 months

Hematopoietic

• Granulocyte count ≥ 1,500/mm^3
• Hemoglobin ≥ 8.0 g/dL
• Platelet count ≥ 100,000/mm^3

Hepatic

• Bilirubin ≤ upper limit of normal (ULN)

• Meets 1 of the following criteria:

  • AST or ALT ≤ ULN AND alkaline phosphatase ≤ 5 times ULN
  • Alkaline phosphatase ≤ ULN AND AST or ALT ≤ 5 times ULN
  • AST or ALT ≤ 1.5 times ULN AND alkaline phosphatase ≤ 2.5 times ULN

Renal

• Creatinine ≤ 1.5 times ULN

Cardiovascular

• No myocardial infarction within the past 180 days
• No congestive heart failure
• No unstable angina
• No clinically significant pericardial effusion or arrhythmias

Other

• No active, unresolved infection
• No prior severe hypersensitivity reaction to docetaxel, irinotecan, or any drug formulated with polysorbate 80
• No other malignancy within the past 5 years except curatively treated basal cell or squamous cell skin cancer or carcinoma in situ of the cervix
• No grade 1 or greater sensory or motor neuropathy
• No other concurrent severe condition that would preclude study participation
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy

• Prior trastuzumab (Herceptin®) required for HER-2-positive patients (unless contraindicated)

Chemotherapy

• See Disease Characteristics
• More than 14 days since prior chemotherapy
• No more than 2 prior chemotherapy regimens for metastatic disease

• No prior irinotecan or docetaxel for metastatic disease

  • Docetaxel as adjuvant therapy allowed
• No other concurrent chemotherapy

Endocrine therapy

• Prior hormonal therapy required for patients with ER- and/or PR-positive tumors (unless contraindicated)

Radiotherapy

• See Disease Characteristics
• At least 30 days since prior radiotherapy
• No concurrent radiotherapy

Surgery

• See Disease Characteristics
• At least 3 weeks since prior major surgery and recovered

Other

• More than 7 days since prior parenteral antibiotic therapy
• No other concurrent experimental drugs