[Predictive role of EGFR mutation status on postoperative prognosis in patients with resected lung adenocarcinomas].

BACKGROUND: At present the proportion of lung adenocarcinomas in NSCLC is higher than before. Thus, the study on prognosis of lung adenocarcinoma is extremely important. The predictive value of epidermal growth factor receptor (EGFR) mutations for prognosis in patients with resected lung adenocarcinomas has not be reported in China. The aim of this study is to analyze the association between the EGFR mutations and the outcomes of patients with resected lung adenocarcinomas.

METHODS: Total of 301 patients with stage Ia-IIIa resected lung adenocarcinomas whose survival had been identified were retrospectively analyzed. Their EGFR mutations were detected by real-time quantitative PCR and DNA sequencing technology together.

RESULTS: The proportion of EGFR mutation was 52.5% (158/301). The 2-year (disease-free survival, DFS) of EGFR-mutant group and wild-type EGFR group was 76.8%, 83.0%; 5-year overall survival (OS) of them was 67.7%, 65.7%. There was no significant difference for two groups (P = 0.252, P = 0.715). Further analysis for subgroups shows that the 2-year DFS, 5-year OS of mutant group and wild-type group in stage I-II was similar. For the patients with stage IIIa, the median DFS, 2-year DFS in mutant group was 12.2 months, 21.1%, lower than the 22.2 months, 42.1% in wild-type group. But there was no significant difference for both groups (P = 0.584, P = 0.295). The median OS, 5-year OS was 34.0 months, 30.8% in mutant group, while 38.7 months, 22.9% in wild-type group. There was no significant difference for both groups (P = 0.907, P = 0.444).

CONCLUSIONS: EGFR-mutant group with resected lung adenocarcinomas has a tendency of lower DFS than the wild-type EGFR group only in stage IIIa, but there was no significant difference for both groups. The EGFR mutation status was not associated with disease-free survival or overall survival in resected lung adenocarcinomas.