The rs689465 AA genotype was significantly associated with longer overall survival (OS) (13.0 months vs 8.8 months, P = 0.019 for log-rank test; hazard ratio [HR] 0.624; 95% confidence internal [CI] 0.418-0.931) and progression-free survival (5.3 months vs 4.0 months, P = 0.018 for log-rank test; HR 0.627; 95% CI 0.421-0.934) compared with AG or GG genotype, especially in patients with adenocarcinoma (P = 0.002), performance status of 1 (P = 0.009) and stage IV disease (P = 0.012), and treated with gemcitabine-based chemotherapy (P = 0.012).