EGFR and non-small cell lung carcinoma: Though first-generation EGFR-TKI with gefitinib or erlotinib has been the standard first-line treatment for metastatic EGFR-mutated NSCLC as demonstrated in various phase 3 randomized-controlled clinical trials [1–7], resistance against these first-generation TKI eventually develops after a median treatment duration of 9 to 13 months.