EGFR Gene Mutation Status Among128NSCLC Patients

Objective To investigate EGFR gene mutations in128patients ofnon-small-cell lung cancers and the relationship between gene mutation andclinicalpathological features，EGFR expression.Methods To collect the tumor tissues of128NSCLC. Genomic DNA wasextracted with the DNeasy Blood＆Tissue Kit or QIAamp DNA FFPE Tissuekit according to the instruction of the manufacturer, mutation analysis of EGFRgene was performed by amplification refractory mutation system（ARMS）.Immunohistochemical staining was performed in61cases of128patients byMaxVision^TM2/HRP kit. To process the clinical data with the software SPSS13.0for chi-square test, and P <0.05for differences with a statistical significance.Results EGFR mutation were found in43.75%（56/128） of our NSCLCcases, of which,20cases located at exon19, all the mutant types are delE,18cases located at the exon21, all the mutant types are L858R and one caselocated at exon20with the mutant type of T790M.Besides, there are15casesmutations that located at more than two exons.94.64%of all the mutant casesharbored exon19or21mutations. The mutant rate was significantly higher inadeno-carcinoma（54.05%） than non-adeno-carcinoma（29.63%）. The mutant rate was significantly higher in non-smoker patients （57.97%） than smokers（27.12%）. The mutant rate was significantly higher in middle-high differentiatedtumors （56.86%） than middle-low differentiated tumors （33.96%）. Moreover,mutation rate was higher in females （53.49%） than in males （38.82%）, but hadno statistically significance. No statistically significance correlation was foundbetween the mutation and patients’ age, metastasis, disease stage, primary fociand metastatic supraclavicular lymph nodes, neoadjuvant chemotherapy.Besides，EGFR expression rate was68.85%，and there was no statisticallysignificance between EGFR expression and patient’ sex, age, smoking,histological types，lymph nodes metastasis，stage and gene mutation（P>0.05）.Conclusion The use of ARMS for the EGFR gene mutations detection isa simple operation method，which requires relatively low instruments and canquickly obtain the result，so it is quite suitable for the clinical application. EGFRgene mutation is significantly higher related to adeno-carcinomas, non-smokers,middle-high differentiated tumors and Zhuang populations. The total mutationrate is about43.75%，with the most common mutation types of the in-framedeletion at exon19and replacement mutations at exon21. The co-mutant rate is26.79%, which is much higher than reported. The mutant rate is not significantlyhigher related to neoadjuvant chemotherapy, primary foci or lymph metastases.There is no statistically significance between EGFR expression and patient’gender，age，smoking，histological types，lymph nodes metastasis，stage andgene mutation.