EGFR and head and neck squamous cell carcinoma: Remarkable clinical benefits of the use of small tyrosine kinase inhibitors (TKIs) targeting the EGFR (e.g. gefitinib and erlotinib) have been observed in patients with non-small cell lung cancer (NSCLC) [32], but these TKIs did not show meaningful clinical efficacy against SCCHN [33, 34].