In this study, we describe the frequency and type of mutations found in biopsies of tumor tissue and in peripheral blood at the time of diagnosis of the disease to determine the most appropriate therapy for each synchronous metastatic colorectal cancer (SMCC) patient: chemotherapy alone or combined with monoclonal antibodies, anti-epidermal growth factor receptor (EGFR) or anti-vascular endothelial growth factor receptor (VEGFR). This evidence concerns the gene EGFR and neoplasm.