Correlation Between EGFR Co-mutation Type And EGFR-TKI Efficacy In Patients With NSCLC Study

BackgroundNon small cell lung cancer is a common tumor that seriously endangers human health.The development of genomics and targeted therapy has changed its treatment status.EGFR-TKI has achieved significant effect in the treatment of lung cancer,but the initial treatment effect of some patients is poor.Some scholars believe that the poor efficacy of EGFR-TKI targeted therapy is closely related to EGFR combined with co-mutation.Therefore,it is urgent to further explore the correlation between EGFR gene mutation and the efficacy of EGFR-TKI in patients with non-small cell lung cancer.ObjectiveThis study mainly analyzes the efficacy difference of EGFR-TKI targeted therapy in patients with EGFR gene mutation positive non-small cell lung cancer after EGFR-TKI first-line treatment,and discusses the efficacy difference of EGFR-TKI targeted therapy with different types of EGFR gene mutation,in order to guide the selection of first-line treatment scheme for patients with EGFR combined with different co-mutation targets.MethodsThe pathological tissue samples of 232 patients with NSCLC diagnosed by histopathology and EGFR positive by gene test in Jincheng people’s Hospital from January2016 to January 2018 were collected.The mutation status of EGFR gene was detected by Illumina sequencing system and EGFR gene mutation detection kit.The mutation status and clinical general data were statistically analyzed by chi square test.Kaplan-Meier curve was used to calculate the difference of progress free survival（PFS）of people with different EGFR mutation status treated with EGFR-TKI first-line treatment.ResultsAmong the 232 EGFR gene mutation-positive patients,79 had single mutation and153 had co-mutation.There was no significant difference between the EGFR single mutation group and the co-mutation group in terms of gender,age,smoking history,pathological type,and clinical staging,and the P values were all >0.05.After first-line EGFR-TKI targeted therapy,the m PFS of patients in the EGFR gene single mutation group was 14.0 months（12.4-18.2 months）.Patients with single mutation of EGFR gene can be divided into 19 del mutation group and L858 R mutation group.Among them,39 patients had 19 del mutation,and the m PFS was 14.1 months（13.9-18.2 months）;40 patients had L858 R,and the m PFS was 13.2 months（12.4-14.9 months）.The difference in median PFS between the 19 del mutation group and the L858 R mutation group was statistically significant（P=0.00）.After first-line EGFR-TKI targeted therapy in patients with genetic co-mutation,the m PFS was 9.2 months（0.4-11.9 months）.There was a statistically significant difference in m PFS（14.0 VS 9.2）between the EGFR gene single mutation group and the co-mutation group（P=0.00）.In the EGFR gene co-mutation group,there were 127 patients with 2 gene loci mutations,and their m PFS was 9.5 months（1.5-11.9months）.Among them,63 patients in the 19 del group had a m PFS of 9.6 months（1.5-11.9months）;64 patients in the L858 R group had a m PFS of 9.4 months（2.0-11.7 months）.Twenty-six patients had 3 or more gene loci mutations,and the m PFS was 2.5 months（0.4-3.9 months）.There was a statistically significant difference in m PFS（14.0 VS 9.2）between the EGFR single mutation group and the co-mutation group（P=0.00）;there was a difference in m PFS（9.5 VS 2.5）between the EGFR gene double mutation group and the multi-mutation group.It was statistically significant（P=0.00）.Conclusions1.Patients with single mutation of EGFR gene are significantly better than patients with co-mutation of EGFR gene of the efficacy of EGFR-TKI targeted therapy in the first line.2.The efficacy of EGFR-TKI targeted therapy in patients with Exon19 deletion mutation alone is better than that in patients with Exon21 L858 R mutation alone.3.PFS in the double mutation group was significantly better than that in the multi mutation group（mutation sites≥3）.