Irinotecan With or Without Oxaliplatin in Treating Patients With Metastatic Colorectal Cancer

RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. It is not yet known if irinotecan is more effective with or without oxaliplatin in treating metastatic colorectal cancer. PURPOSE: Randomized phase III trial to compare the effectiveness of irinotecan with or without oxaliplatin in treating patients who have metastatic colorectal cancer.

OBJECTIVES: * Compare the overall survival of patients with metastatic colorectal cancer treated with irinotecan with or without oxaliplatin. * Compare the response rate, time to tumor-related worsening of symptoms, time to disease progression, onset and duration of responses, and duration of disease stabilization in these patients treated with these regimens. * Compare the safety of these regimens in these patients. OUTLINE: This is a randomized, open label, multicenter study. Patients are stratified according to Karnofsky performance status (50-60% vs 70-100%), number of metastatic organs involved (1 vs 2 or more), lactic dehydrogenase (no greater than 1.5 times upper limit of normal (ULN) vs greater than 1.5 times ULN), and prior fluorouracil chemotherapy (adjuvant vs first-line treatment for metastatic disease). Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients receive irinotecan IV over 90 minutes on day 1. * Arm II: Patients receive oxaliplatin IV over 120 minutes followed by irinotecan IV over 30 minutes on day 1. Courses repeat in each arm every 3 weeks for 1 year in the absence of disease progression or unacceptable toxicity. Patients are followed at 30 days, every 4 weeks for 3 months, and then every 3 months thereafter. PROJECTED ACCRUAL: A total of 596 patients (298 per arm) will be accrued for this study within 18 months.