Fluorouracil and Leucovorin With or Without Oxaliplatin in Treating Patients With Recurrent Metastatic Colorectal Cancer

RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Combining more than one drug may kill more tumor cells.
PURPOSE: Randomized phase II trial to study the effectiveness of combining fluorouracil and leucovorin with or without oxaliplatin in treating patients who have recurrent metastatic colorectal cancer.