EGFR and head and neck squamous cell carcinoma: Epidermal growth factor receptor (EGFR) and the mesenchymal-epithelial transition factor (MET; also known as hepatocyte growth factor [HGF] receptor) are receptor tyrosine kinases that are coexpressed in many tumors, including non-small cell lung cancers (NSCLC), colorectal cancers (CRC), and head and neck cancers (HNSCC) [1–3].