Detection And Biological Significance Of EGFR Gene Mutations In Non-Small Cell Lung Cancer

ObjectiveTo detect the mutations of epidermal growth factor receptor(EGFR) in patients with non-small cell lung cancer(NSCLC), and to investigate the characteristics of EGFR mutation and its biological significance of treatment for NSCLC.MethodFresh specimens of lung cancer tissues and corresponding paracarcinoma tissues were collected from 46 NSCLC patients. DNA was extracted from the 46 specimens respectively. Exon18,19,20,21 EGFR genes were amplified by PCR to be sequenced.ResultSomatic mutations in tyrosine kinase(TK) domain of EGFR in 12 of 46 NSCLC patients (26.1%) were identified in carcinoma tissues. Mutations were not found in corresponding paracarcinoma tissues. For 12 mutations, 9 cases(9/12,75.0%)are in-frame deletion in exon 19 and 3 cases ( 3/12,25.0% ) are amino acid substitution in exon21.Mutation rate was significantly higher in adenocarcinoma with bronchioloalveolar carcinoma(BAC) component(7/9,77.8%) than pure adenocarcinoma (5/23, 21.7%), significantly higher in women(9/15,60%) than men(3/31,9.7%),significantly higher in non-smokers (9/20,45%)than smokers(3/26,11.5%). ConclusionSomatic mutations of EGFR gene exist in NSCLC patients of China. Female, non-smoker and adenocarcinoma with any degree of BAC predicted higher presence of EGFR mutations.