EGFR and metastatic colorectal cancer: Anti-EGFR therapies are mainly used for treating three types of cancers, which are NSCLC bearing kinase-activating mutations in EGFR for TKIs (4, 88, 89), about 10% of advanced metastatic colorectal cancers (CRCs) for anti-EGFR mAbs (90, 91), and locoregional advanced head and neck cancers (HNCs) for combination of mAbs with radiotherapy (92, 93).