Validation of EGFL6 expression as a prognostic marker in patients with lung adenocarcinoma in Taiwan: a retrospective study

Abstract

Objective: Lung adenocarcinoma is a non-small cell lung cancer, a common cancer in both genders, and has poor clinical outcome. Our aim was to evaluate the role of epidermal growth factor (EGF)-like domain multiple 6 (EGFL6) and its prognostic significance in lung adenocarcinoma.

Methods: EGFL6 expression was studied by immunohistochemical staining of specimens from 150 patients with lung adenocarcinoma. The correlation between clinicopathological features and EGFL6 expression was quantitatively analysed. We used Kaplan-Meier analysis and Cox proportional hazard models to examine the prognostic value of EGFL6 in terms of overall survival.

Results: No significant correlation was found between EGFL6 expression and clinical parameters. However, patients with high levels of EGFL6 expression showed a tendency towards poor prognosis, with borderline statistical significance. Grouping the patients according to a medium age value revealed a significant association between high EGFL6 expression and poor clinical outcome in young patients. This finding was further confirmed by grouping the patients into three groups according to age. HR in patients with high EGFL6 expression was higher in younger patients than in older patients.

Conclusion: High EGFL6 expression may serve as a marker for poor prognosis of lung adenocarcinoma, especially in younger patients.

Keywords: egf like domain multiple 6; egfl6; lung adenocarcinoma;; non-small cell lung cancer; overall survival; prognosis.

Figure 1

Representative immunostaining of EGFL6 in tissue arrays of lung adenocarcinoma specimens. EGFL6 expression levels were (A) 0, (B) 1+ and (C) 2+. EGFL6, epidermal growth factor-like domain 6.

Figure 2

Kaplan-Meier actuarial analysis of EGFL6 expression with respect to overall survival of (A) all patients and (B) patients younger than 69 years of age. EGFL6, epidermal growth factor-like domain 6.