Two mAbs (cetuximab and panitumumab) and two TKIs (gefitinib and erlotinib), as first-generation EGFR inhibitors, have been used for the treatment of NSCLC, pancreatic cancer, HNSCC, renal cancer, and colorectal cancer (CRC) [38]. The gene discussed is EGFR; the disease is head and neck squamous cell carcinoma.