EGFR and non-small cell lung carcinoma: There are five selective EGFR TKIs approved for the treatment of EGFR-mutated NSCLC, namely, gefitinib (GEF) and erlotinib (ERL) (first-generation reversible EGFR TKIs), afatinib (AF) and dacomitinib (DAC) (second-generation irreversible EGFR TKIs), and osimertinib (OS) (third-generation irreversible EGFR TKI).