Comparing Two Combination Chemotherapy Regimens in Treating Patients With Metastatic Colorectal Cancer

DISEASE CHARACTERISTICS:

• Histologically confirmed unresectable metastatic adenocarcinoma of the colon or rectum

• Bidimensionally measurable or evaluable disease outside previously irradiated area

  • No bone metastasis as target lesion
  • At least 1 cm if spiral CT scan OR
  • At least 2 cm if conventional CT scan
• No CNS metastasis
• No symptomatic ascites or pleural effusion that is not evacuated
• No total or partial bowel obstruction

PATIENT CHARACTERISTICS:

Age:

• 18 to 80

Performance status:

• ECOG 0-2
• WHO 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Neutrophil count at least 1,500/mm3
• Platelet count at least 100,000/mm3

Hepatic:

• Alkaline phosphatase less than 5 times upper limit of normal (ULN)

Renal:

• Creatinine less than 3 times ULN
• No uncontrolled hypercalcemia

Cardiovascular:

• No uncontrolled congestive heart failure, angina pectoris, hypertension, or arrhythmias

Other:

• No peripheral sensory neuropathy
• No prior significant neurologic or psychiatric disorders
• No other malignancy within past 5 years except adequately treated carcinoma in situ of the cervix or basal or squamous cell skin carcinoma
• No active infection
• No other concurrent serious disease
• Not pregnant or nursing
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior immunotherapy for metastatic disease

Chemotherapy:

• Prior adjuvant chemotherapy allowed, provided progression-free interval of more than 6 months since end of last course
• No prior oxaliplatin or irinotecan
• No prior chemotherapy for metastatic disease
• No other concurrent chemotherapy

Endocrine therapy:

• Not specified

Radiotherapy:

• See Disease Characteristics
• No concurrent radiotherapy

Surgery:

• Concurrent surgery allowed

Other:

• At least 30 days since other prior investigational drugs
• No other concurrent investigational treatment
• No other concurrent antitumoral treatment