First-generation EGFR TKIs are well-established molecularly driven therapies for lung cancer harboring specific types of activating EGFR mutations involved in the development of NSCLC (classical sensitive EGFR mutations, i.e., deletions in exon 19 and the single-point substitution mutation L858R in exon 21) [8–9]. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.