Prognostic role of epidermal growth factor receptor mutation status in patients with de novo lung adenocarcinoma

Background: To explore the relationship between the status of epidermal growth factor receptor (EGFR) and overall survival (OS) in de novo lung adenocarcinoma.

Methods: We retrospectively analyzed 291 lung adenocarcinoma subjects with exact EGFR status. The cases were divided into a mutant-type group (124 patients) and wild-type group (167 patients) according to the status of EGFR. The general information, OS, and possible risk factors influencing the OS were also evaluated.

Results: The EGFR mutation rate was 42.6% (124/291 patients), and there were statistically significant differences in gender, smoking history, and OS (P<0.05), but no significant difference in diagnosed age, alcohol history, TNM stage, clinical stage, and immunohistochemistry between the two groups (P>0.05). The most common subtypes of EGFR mutations were exon 19 and exon 21. The median OS of the total population was 30.20 months [95% confidence interval (CI): 25.94-34.46 months] and the OS in the mutant-type group was better than in the wild-type group (P<0.001). Cox regression demonstrated that N stage, M stage, and EGFR status were the risk factors for OS in de novo lung adenocarcinoma patients (P<0.001), and the relative risk were 1.398 (95% CI: 1.214-1.609), 2.427 (95% CI: 1.780-3.310), and 2.030 (95% CI: 1.528-2.699), respectively.

Conclusions: The OS of EGFR mutant individuals was better than that of wild-type patients in de novo lung adenocarcinoma patients. EGFR mutation may be a useful prognostic indicator in lung adenocarcinoma.