Inclusion Criteria

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