Epidermal growth factor +61 a/g polymorphisms as predictors for survival in advanced lung adenocarcinoma and squamous cell carcinoma.

Abstract

e19069 Background: Our purpose was to evaluate epidermal growth factor (EGF) +61 A/G polymorphisms as prognostic marker for progression free survival (PFS) and overall survival (OS) in advanced non-small cell lung cancer (NSCLC). Methods: 148 Portuguese Caucasian, medically treated for NSCLC between February 2010 and April 2011, were included in this study. DNA was extracted from peripheral blood leucocytes. Genotyping was performed by PCR-RFLP. Chi-square test, Kaplan-Meier estimator and cox regression hazard model were used to assess the prognostic value of selected polymorphisms. Results: Genotype frequency was A/A (25.3%), A/G (55.6%), G/G (19.2%). We found no differences in PFS among EGF+61 A/G polymorphisms and NSCLC (p = 0.339). However in G/G+A/G genotype patients group showed a trend to higher OS than A/A genotype (p = 0.055). Moreover, adenocarcinoma and squamous cell (SC) lung cancers patients harboring in A/G+G/G genotype group showed a trend to higher OS than those harboring A/A genotype (p = 0.074). Furthermore, patients in advanced stages carrying G/G genotype presented higher OS than those carrying A/A genotype: 13 months versus 3 months (adenocarcinoma); and 6 months versus 1 month (SC lung cancer), respectively, p = 0.043. Conclusions: We were able to observe the G/G genotype of EGF+61 A/G polymorphisms as a positive predictor for survival in medically treated advanced adenocarcinoma and squamous cell lung carcinoma patients. In future, our findings could be used as a biological marker in order to identify eligible NSCLC subgroups with potential improved response to EGFR tyrosine-kinase-inhibitors.