Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are regarded as the standard treatment for stage IV EGFR-mutant non-small cell lung cancer (NSCLC) patients [1], but 50–70% of patients have developed T790M mutations associated with resistance after receiving the first- or second-generation TKIs [2, 3]. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.