Celecoxib Combined With Fluorouracil and Leucovorin in Treating Patients With Resected Stage III Adenocarcinoma (Cancer) of the Colon

RATIONALE: Drugs used in chemotherapy, such as fluorouracil and leucovorin, work in different ways to stop tumor cells from dividing so they stop growing or die. Celecoxib may stop the growth of tumor cells by blocking the enzymes necessary for their growth. It is not yet known whether fluorouracil and leucovorin are more effective with or without celecoxib in treating resected stage III adenocarcinoma (cancer) of the colon. PURPOSE: This randomized phase III trial is studying celecoxib, fluorouracil, and leucovorin to see how well they work compared to fluorouracil and leucovorin in treating patients who have undergone surgery for stage III colon cancer.