Prognostic analysis of patients with mutant and wild-type EGFR gene lung adenocarcinoma

PURPOSE: The purpose of this study was to investigate the relationship between epidermal growth factor receptor (EGFR) gene mutation and clinicopathological features of lung adenocarcinoma, and the prognostic and therapeutic value of EGFR. METHODS: EGFR gene mutations were detected in 424 patients with lung adenocarcinoma by amplification refractory mutation system (ARMS). RESULTS: The total EGFR gene mutation rate was 55.2% (234/424) and EGFR gene mutation rates were statistically different in gender, smoking status, and pathological degree (P<0.05). The overall survival (OS) time of lung adenocarcinoma patients with mutation of exon 18 was lower than those with mutation of exon 19 and exon 21 (both P<0.05), but no significant difference was seen between those with mutation of exon 19 and exon 21 (P>0.05). Among 424 cases of lung adenocarcinoma, multivariate analysis showed that EGFR gene mutation, age, gender, clinical stages, and pathological degree (P<0.05) were statistically significant prognostic factors. In multivariate analysis, prognostic factors of patients with EGFR gene mutation were associated with EGFR-TKI treatment, surgery treatment, pathological degree, clinical stages, and age (P<0.05), whereas in patients without EGFR gene mutation, prognostic factors were related to surgery treatment, pathological degree, clinical stages, gender, age, and smoking status (P<0.05). CONCLUSION: The OS time of patients with mutation of exon 18 was lower than those of exon 19 and exon 21. EGFR-TKI treatment was an independent positive predictor in patients with EGFR gene mutation. Surgery treatment, age, clinical stages, and pathological degree were independent prognostic factors in Chinese patients with lung adenocarcinoma no matter whether with EGFR gene mutation or not.