Combination Chemotherapy With or Without Bevacizumab in Treating Patients Who Have Undergone Surgery for High Risk Stage II or Stage III Colon Cancer

RATIONALE: Drugs used in chemotherapy work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Monoclonal antibodies, such as bevacizumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them. Bevacizumab (Bv) may also stop the growth of tumor cells by blocking blood flow to the tumor. Giving combination chemotherapy together with bevacizumab after surgery may kill any tumor cells that remain after surgery. It is not yet known whether giving combination chemotherapy together with bevacizumab is more effective than combination chemotherapy alone in treating colon cancer in adjuvant setting.
PURPOSE: This randomized phase III trial is studying two different combination chemotherapy regimens with or without bevacizumab to compare how well they work in treating patients who have undergone surgery for high risk stage II or stage III colon cancer.