In particular, acquired therapeutic resistance to anti-EGFR monoclonal antibody treatment in patients with mCRC has been attributed to the various tumor-promoting mutations in rat sarcoma (KRAS), v-raf murine sarcoma viral oncogene homolog B1 (BRAF), and phosphatidylinositol 3-kinase catalytic subunit alpha (PI3KCA) genes [6]. The gene discussed is EGFR; the disease is neoplasm.