EGFR and metastatic colorectal cancer: The metastatic colorectal cancer (mCRC) patients are used with various combinations of chemotherapeutic drugs and biologics, including vascular endothelial growth factors inhibitors (VEGF inhibitors; e.g., bevacizumab) and epidermal growth factor receptors inhibitors (EGFR inhibitors; e.g., cetuximab) [4].