EGFR and non-small cell lung carcinoma: EGFR mutations have been detected in about 14% of patients with non-small cell lung cancer, EGFR-TKI can inhibit signal transduction by blocking the phosphorylation process of tyrosine kinase region, so as to play an anti-tumor role.17,18 In recent years, erlotinib and Gefitinib are molecular targeted drugs with high application frequency, as a kind of EGFR-TKI, they can produce certain antitumor effects by preventing EGFR phosphorylation and inhibiting signal transduction such as proliferation and apoptosis of tumor cells.