In comparison with chemotherapy, EGFR-tyrosine kinase inhibitors (TKI), including gefitinib, erlotinib and afatinib, have provided a better outcome and quality of life for patients with advanced EGFR-mutant non-small cell lung cancer (NSCLC) and have become one of the standard first line therapies [4–6]. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.