Abstract B11: EGFR polymorphism as a predictor of clinical outcome in advanced lung cancer patients treated with EGFR-TKI

Background: Mutations in the epidermal growth factor receptor (EGFR) have been confirmed as predictors of efficacy for EGFR-tyrosine kinase inhibitors (TKIs). We investigated whether polymorphisms of the EGFR gene were associated with clinical outcome in NSCLC patients treated with EGFR-TKI. Methods: A polymorphic dinucleotide repeat (CA simple sequence repeat 1 [CA-SSR1]) in intron one and single nucleotide polymorphisms in the promoter region (SNP -216 GG or GT) were evaluated in 71 NSCLC patients by PCR-RFLP and DNA sequencing. Genetic polymorphisms were correlated with clinical outcomes of EGFR-TKIs. Results: SNP-216G/T polymorphisms were associated with the efficacy of EGFR-TKI. The response rate for the SNP-216G/T was significantly higher than that for the GG (62.5% vs. 27.4%, P=0.044). SNP-216G/T genotype was also associated with longer progression-free survival compared with GG genotype (16.7 months vs. 5.1 months, P=0.005). However, Genotypes for the CA-SSR1 was not associated with the efficacy of EGFR-TKI. Conclusions: SNP-216G/T polymorphism is potential predictor for clinical outcome in NSCLC patients treated with EGFR-TKI.