EGFR and neoplasm: Although targeted therapy with CTX has several advantages, CTX treatment slowly leads to acquired resistance in most HNSCC patients for one of the following reasons: alteration in EGFR or downstream effectors, activation of a different pathway or protein involved in tumor progression, and induction of mechanisms involved in the immunosuppressive tumor microenvironment (Chen et al., 2010; Ortiz-Cuaran et al., 2021).