Irinotecan or Fluorouracil Plus Leucovorin in Treating Patients With Previously Treated Metastatic Colorectal Cancer

DISEASE CHARACTERISTICS:

• Diagnosis of metastatic colorectal adenocarcinoma incurable by surgery or not amenable to radiotherapy with curative intent

• Progressive disease after one of the following prior treatments for metastatic disease:

  • Oxaliplatin-based chemotherapy
  • Irinotecan and oxaliplatin combination chemotherapy

• At least 1 measurable lesion

  • At least 20 mm in at least one dimension
• No known CNS metastases or carcinomatous meningitis

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• ECOG 0-2

Life expectancy:

• At least 12 weeks

Hematopoietic:

• Absolute neutrophil count at least 2,000/mm^3
• Platelet count at least 100,000/mm^3

Hepatic:

• Bilirubin no greater than 0.5 mg/dL above upper limit of normal (ULN)
• AST no greater than 5 times ULN

Renal:

• Creatinine no greater than 1.5 times ULN

Cardiovascular:

• No unstable angina
• No symptomatic congestive heart failure
• No serious uncontrolled cardiac arrhythmia

Other:

• No active or uncontrolled infection
• No evidence of other serious illness
• No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer or noninvasive carcinomas
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No concurrent sargramostim (GM-CSF)

Chemotherapy:

• See Disease Characteristics
• At least 4 weeks since prior chemotherapy
• No more than 1 prior chemotherapy regimen for advanced colorectal cancer
• Prior adjuvant chemotherapy allowed

Endocrine therapy:

• Not specified

Radiotherapy:

• See Disease Characteristics
• No prior radiotherapy to more than 25% of bone marrow

Surgery:

• See Disease Characteristics
• At least 4 weeks since prior major surgery