RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Giving drugs at the time of day that allows for the best drug response may allow the doctor to give higher doses of chemotherapy drugs and kill more tumor cells.

PURPOSE: Randomized phase II trial to determine the best time to give irinotecan combined with fluorouracil, leucovorin, and oxaliplatin in treating patients who have colorectal cancer.

OBJECTIVES:

• Determine the role of peak delivery time on the tolerability of irinotecan when administered with chronomodulated fluorouracil, leucovorin calcium, and oxaliplatin as first- or second-line therapy in patients with locoregional or metastatic colorectal cancer.
• Determine the antitumor activity of this regimen.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to participating center, WHO performance status (0-1 vs 2), and line of treatment (first vs second). Patients are randomized to receive irinotecan at 1 of 6 different times of the day.

Patients receive irinotecan IV over 6 hours on day 1 and fluorouracil IV and leucovorin calcium IV over 11 hours followed by oxaliplatin IV over 11 hours on days 2-5. Courses repeat every 21 days in the absence of disease progression or unacceptable toxicity.

Patients are followed every 4 weeks until disease progression and then every 8 weeks thereafter.

PROJECTED ACCRUAL: A maximum of 186 patients (31 per irinotecan administration time) will be accrued for this study within 2 years.

DISEASE CHARACTERISTICS:

• Histologically confirmed colorectal cancer
• Unresectable metastatic or locoregional disease
• At least 1 measurable lesion outside a previously irradiated area or an area treated with physical devices (e.g., cryotherapy, laser, or thermoablation)
• No prior enrollment in EORTC-05963
• No symptomatic brain metastases

PATIENT CHARACTERISTICS:

Age:

• Over 18

Performance status:

• WHO 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Neutrophil count greater than 2,000/mm^3
• Platelet count at least 90,000/mm^3

Hepatic:

• Bilirubin no greater than 2 times upper limit of normal (ULN)

Renal:

• Creatinine no greater than 1.5 times ULN
• No uncontrolled hypercalcemia

Cardiovascular:

• No overt cardiac disease

Pulmonary:

• No severe respiratory illness

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• Male patients must use effective barrier contraception during and for up to 6 months after study
• No baseline diarrhea greater than grade I (must have less than 4 stools per 24 hours)
• No prior grade III or IV toxicity related to irinotecan
• No sensory or motor neuropathy with functional impairment
• No prior hypersensitivity to any study drug
• No other primary tumor except basal cell skin cancer or carcinoma in situ of the cervix
• No uncontrolled infectious or chronic disease
• No psychological, familial, sociological, or geographical condition that would preclude study

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No concurrent prophylactic growth factor therapy

Chemotherapy:

• At least 1 month since prior chemotherapy
• No prior irinotecan, fluorouracil, leucovorin calcium, and oxaliplatin as combination therapy
• Other prior therapy containing irinotecan and/or oxaliplatin allowed
• No more than 1 prior chemotherapy regimen for metastatic or locoregional disease
• Adjuvant chemotherapy considered first-line therapy if tumor relapsed within 6 months of completion of therapy

Endocrine therapy:

• No concurrent corticosteroids except for emergencies

Radiotherapy:

• See Disease Characteristics
• Palliative radiotherapy for bone lesion allowed except for disease progression

Surgery:

• See Disease Characteristics