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

Background: NSCLC is a disease involving uncontrolled cell growth, which could result in metastases intonearby tissues beyond the lungs. Materials and
Methods: The aim of the present study was to analyze the influenceof 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 NSCLCpatient survival was analyzed by the Kaplan-Meier method.
Results: We analyzed EGFR gene expression andobserved mean increased gene expression of 13.5 fold in NSCLC patients. Values reflected overall survival ofpatients with a median of 15.8 months in the cases of <13 fold increased gene expression vs 6.7 months with >13fold increased EGFR gene expression (p=0.005). Distant metastatic patients with <13 fold increased EGFR geneexpression had 7.9 months of median survival time while>13 fold increased EGFR gene expression had only 5months of median survival time (p=0.03). Non metastatic patients with <13 fold increased EGFR gene expressionhad 18 months of median survival time as compared to only 7.1 months with >13 fold increased expression.
Conclusions: Higher cell free EGFR mRNA expression may play an important role in causing distant metastasesand reducing overall survival of NSCLC patients in the Indian population.