PURPOSE: This randomized phase III trial is studying two different combination chemotherapy regimens to compare how well they work in treating patients with colorectal cancer and resectable metastases.

OBJECTIVES:

Primary

• Compare the 2-year disease-free survival rate in patients treated with these regimens.

Secondary

• Compare the overall survival of patients treated with these regimens.
• Compare the tolerability of these regimens in these patients.
• Compare the quality of life of patients treated with these regimens.
• Compare the objective response rate, postoperative complication rate, and transfusing rate in patients having metastasis surgery,
• Determine the pharmacogenetics of these regimens in these patients.

OUTLINE: This is a randomized, open-label, multicenter phase III study. Patients are stratified according to prior chemotherapy (perioperative vs postoperative), prior treatment (surgery only vs radiotherapy with or without surgery), and Blumgart score (0-1 vs 2-3 vs 4-5). Patients are randomized to 1 of 2 treatment arms.

• Arm I (FOLFOX 4): Patients receive FOLFOX 4 combination chemotherapy comprising oxaliplatin 85mg/m² IV over 2 hours, leucovorin calcium IV over 2 hours, fluorouracil IV bolus /15min and fluorouracil continuously over 22 hours on day 1. Treatment repeats every 2 weeks for 12 courses in the absence of disease progression or unacceptable toxicity.
• Arm II (FOLFOX 7 and FOLFIRI): Patients receive FOLFOX 7 combination chemotherapy comprising high-dose oxaliplatin 130mg/m² IV over 2 hours and leucovorin calcium IV over 2 hours on day 1 and fluorouracil IV over 46 hours on days 1 and 2. Treatment repeats every 2 weeks for 6 courses in the absence of disease progression or unacceptable toxicity. Patients then receive FOLFIRI combination chemotherapy comprising irinotecan hydrochloride 180mg/m² IV over 30-90 minutes and leucovorin calcium and fluorouracil IV bolus /15min on day 1, and fluorouracil IV continuously over 46 hours on days 1 and 2. Treatment repeats every 2 weeks for 6 courses in the absence of disease progression or unacceptable toxicity.

Patients in both arms who have undergone prior resection of metastatic lesions may undergo surgery after 6 courses of chemotherapy or after chemotherapy is completed.

Quality of life is assessed at baseline and after courses 4, 8, and 12.

After completion of study treatment, patients are followed periodically for 5 years.

PROJECTED ACCRUAL: A total of 284 patients will be accrued for this study.

MAIN ELIGIBILITY CRITERIA

DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the colon or rectum
• Resectable or resected metastatic disease,

PATIENT CHARACTERISTICS:

• WHO performance status 0-2
• Alkaline phosphatase ≤ 5 times upper limit of normal (ULN)
• Bilirubin ≤ 2 times normal
• Creatinine ≤ 135 mmol/L or creatinine clearance ≥ 60 mL/min
• SGOT and SGPT ≤ 3 times ULN
• No peripheral neuropathy that affects normal functions
• No unresolved complications from prior surgery

PRIOR CONCURRENT THERAPY:

• At least 1 year since prior FOLFOX 4 or FOLFIRI regimen in the adjuvant setting
• No concurrent participation in another clinical trial
• Recovered from prior therapy