Lung cancer has the highest incidence and mortality of malignant tumors in the world, of which Non-Small Cell Lung Cancer (NSCLC) accounts for about 80 % and has a low 5-year survival rate,1 In recent years, molecular targeted therapy for lung cancer has become increasingly mature in clinical application, among which Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors (EGFR-TKI) have been the most widely used, making a breakthrough in the treatment of NSCLC.2 The gene discussed is EGFR; the disease is lung cancer.