Efficacy Of EGFR-Tyrosine Kinase Inhibitors And Clinical Pathologic Features Analysis Between Exon 19 Deletion And L858R Mutation With Advanced Non-Small Cell Lung Cancer

Objective:To study the efficacy of epidermal growth factor receptor-tyrosine kinase inhibitors(EGFR-TKIs) in patients with advanced non-small cell lung cancer harbouring exon 19 deletion and L858R mutation and analyze its clinical pathologic features and side effects.Methods:127 patients who were diagnosed histopathologically as advanced non-small cell lung cancer harboring EGFR mutations during 2008-2015 in Guangxi Tumor Hospital were enrolled. We used SPSS statistical software 16.0 to analyze.The median progression-free survival (mPFS) and median overall survival (mOS) of different groups were estimated by Kaplan-Meier approach and Log-Rank test. The Chi-square test or Fisher’s exact test was performed to analyze the association between the EGFR mutation status and the clinicopathological characteristics of patients.Results:1.The objective response rate(ORR)was 52.8% and disease control rate(DCR)was 93.7%.Either in overall or first-line,ORR and DCR in patients with skin rash were higher than those with no rash(p<0.05).In the second line, ORR in patients with 19 exon deletion were higher than those with exon 21(p<0.05).2.Overall median progression free survival(mPFS) was 14.7 months(95%CI:12.8 to 16.6), Median overall survival(mOS) was 22 months(95%CI:18.2 to 25.8).MOS in exon 19 deletion and exon 21 was 33.2 months vs 19.3 months,respectively.MPFS and mOS in patients horboring exon 19 mutation were longer than those with exon 21 no matter with first-line or a second line, but the differences were no statistically significant. Patients with skin rash had longer mPFS than those without rash(p<0.05).3. The incidence of adverse events and skin rash related targeted treatment were 55.1%(70/127) and 87.1%,respectivley.Most of rash was grade 1 or 2,Four cases were grade 3 and no grade 4 or 5.Conclusions:1.ORR and mPFS in patients with skin rash are higher than those without rash(p<0.05)2.Age,sex,TNM stage,treatment and smoking status of patients have no correlation with the efficacy of EGFR-TKIs;3.Patients with exon 19 deletion have longer mPFS and mOS compared to exon 21 with statistically significant differences. As to first-line or a second line, exon 19 mutation is slightly improved than exon 21,but statistical significance has no reached.4.The efficacy of EGFR-TKIs are remarkable and its toxicities are tolerable.