Regorafenib monotherapy is currently the third- or fourth-line standard of care for patients with metastatic colorectal cancer (mCRC) who have been previously treated with fluoropyrimidines, irinotecan, oxaliplatin, and monoclonal antibodies targeting vascular endothelial growth factor (VEGF), and monoclonal antibodies targeting epidermal growth factor receptor (EGFR) for those with KRAS wild-type cancers. This evidence concerns the gene EGFR and cancer.