 - No prior chemotherapy treatment for advanced or metastatic colorectal cancer. Patients may have received prior adjuvant chemotherapy or radiation with radiosensitizing chemotherapy. The last course of adjuvant chemotherapy must have concluded 12 months prior to registration. Patients may not have previously received irinotecan, oxaliplatin, antiangiogenesis agent, or EGFR inhibitor therapy in either the adjuvant or metastatic setting. No concurrent use of additional investigational agents including up to 4 weeks prior to enrollment is allowed while participating in this study. 