EGFR and head and neck squamous cell carcinoma: However, therapies targeting wild-type EGFR in tumors such as head and neck squamous cell carcinoma (HNSCC) have been less effective due to intrinsic and acquired tumor resistance to EGFR inhibitors (Leemans et al., 2011; Rieke et al., 2016; Jiang et al., 2014).