Effect of rs2293347 polymorphism in EGFR on the clinical efficacy of gefitinib in patients with non-small cell lung cancer

Background and objective Genetic variations of the epidermal growth factor receptor (EGFR) may alter the protein function and therapeutic efficacy of EGFR inhibitors. The aim of this study is to investigate the association between single nucleotide polymorphism rs2293347 in EGFR and the clinical outcome in patients with advanced non-small cell lung cancer (NSCLC) treated with gefitinib. Methods A total of 88 advanced NSCLC patients treated with gefitinib were analyzed in the present study. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was conducted to analyze the genotype. The association study was performed between genotypes and clinical efficacy among 88 patients. Results rs2293347 was associated with the efficacy of gefitinib. The response rate for the rs2293347 GG was significantly higher than that for the GA or AA (71.4% vs 36.0%, P=0.002). rs2293347 GG genotype was also associated with longer progression-free survival compared with GA or AA genotype (10 months vs 3 months, P=0.005). No significant difference was shown on the overall survival (OS) (P=0.409). Conclusion rs2293347 polymorphism in exon 25 is associated with the clinical efficacy of gefitinib and may be a potential biomarker to predict the clinical outcome in advanced NSCLC patients treated with gefitinib.