Bevacizumab and Oxaliplatin Combined With Irinotecan or Leucovorin and Fluorouracil in Treating Patients With Metastatic or Recurrent Colorectal Cancer

RATIONALE: Drugs used in chemotherapy, such as oxaliplatin, irinotecan, leucovorin, and fluorouracil, 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 may also stop the growth of colorectal cancer by blocking blood flow to the tumor. Giving bevacizumab together with combination chemotherapy may be a better way to block tumor growth. Studying the amount of an enzyme found in the tumor may help doctors plan the best treatment.
PURPOSE: This randomized phase II trial is studying giving bevacizumab, oxaliplatin, and irinotecan or giving bevacizumab, oxaliplatin, leucovorin, and fluorouracil in treating patients with metastatic or recurrent colorectal cancer.