Cell Free EGFR mRNA Expression and Implications for Survival and Metastasis in Non-Small Cell Lung Cancer Cases.

Abstract

NSCLC is a disease involving uncontrolled cell growth, which could result in metastases into nearby tissues beyond the lungs. The aim of the present study was to analyze the influence of epidermal growth factor receptor (EGFR) gene expression on metastasis and survival in NSCLC patients. The present case-control study included 100 cases of NSCLC patients and 100 age and sex matched controls. EGFR gene expression was analyzed by quantitative real time PCR using serum RNA. Association with NSCLC patient survival was analyzed by the Kaplan-Meier method. We analyzed EGFR gene expression and observed mean increased gene expression of 13.5 fold in NSCLC patients. Values reflected overall survival of patients with a median of 15.8 months in the cases of <13 fold increased gene expression vs 6.7 months with >13 fold increased EGFR gene expression (p=0.005). Distant metastatic patients with <13 fold increased EGFR gene expression had 7.9 months of median survival time while>13 fold increased EGFR gene expression had only 5 months of median survival time (p=0.03). Non metastatic patients with <13 fold increased EGFR gene expression had 18 months of median survival time as compared to only 7.1 months with >13 fold increased expression. Higher cell free EGFR mRNA expression may play an important role in causing distant metastases and reducing overall survival of NSCLC patients in the Indian population.