Cetuximab and/or Bevacizumab Combined With Combination Chemotherapy in Treating Patients With Metastatic Colorectal Cancer

1. Locally Advanced or Metastatic Colorectal Cancer 1. Eligible patients must have histologically or cytologically documented adenocarcinoma of the colon or rectum. Patients must have either locally advanced (unresectable) or metastatic disease. Patients with resected primary tumors who have documented metastases are eligible. Documentation of residual disease by CT scan or surgeon's notes is required for all patients, and histologic confirmation of metastases is strongly encouraged. 2. Patients with a history of colorectal cancer treatment by surgical resection who develop radiological or clinical evidence of metastatic cancer do not require separate histological or cytological confirmation of metastatic disease unless: * Either an interval of greater than five years has elapsed between the primary surgery and the development of metastatic disease or * The primary cancer was stage I. Clinicians should consider biopsy of lesions to establish the diagnosis of metastatic colorectal cancer in each case if there is substantial clinical ambiguity regarding the nature or source of apparent metastases. 3. At the time of randomization, the intent of this treatment must be indicated palliative or neoadjuvant chemotherapy with the potential for resection of all sites of metastatic disease. 2. Only patients with a wildtype K-ras gene as determined by the laboratory at the SWOG Solid Tumor Repository or by a local CLIA-certified laboratory are eligible. Patients wi…