[目的]研究胸苷酸合成酶增强子(TSER)多态性与晚期结直肠癌患者以5-Fu为基础方案化疗疗效关系。[方法]收集经病理学确诊的晚期结直肠癌患者59例,化疗前抽静脉血,提取白细胞,用PCR技术检测TSER基因型。所有患者均经FOLFOX4方案治疗,以肿瘤化疗疗效评价标准(WHO)评价疗效。[结果]3R/3R、2R/2R+2R/3R基因型组化疗的有效率分别为19.4%(7/36)、47.8%(11/23),3R/3R与2R/2R、2R/3R两组对5-Fu为基础方案化疗疗效关系存在显著差异性(P<0.05)。[结论]晚期结直肠癌患者TSER多态性与5-Fu为基础方案化疗疗效可能存在相关性,基因型检测可能有助于晚期大肠癌的化疗。 [Objective] To investigate the relationship between TSER polymorphism and 5-Fu-based regimen in patients with advanced colorectal cancer. [Method] 59 patients with pathologically diagnosed advanced colorectal cancer were collected. Venous blood was drawn before chemotherapy and leukocytes were extracted. TSER genotypes were detected by PCR. All patients were treated with FOLFOX4 regimen to evaluate the efficacy of tumor chemotherapy evaluation criteria (WHO). [Results] The effective rates of 3R / 3R and 2R / 2R + 2R / 3R genotype chemotherapy were 19.4% (7/36), 47.8% (11/23) There was significant difference between the two groups on the efficacy of 5-Fu-based chemotherapy (P <0.05). [Conclusion] TSER polymorphism in patients with advanced colorectal cancer may be correlated with 5-Fu-based regimen chemotherapy. Genotyping may be helpful for the chemotherapy of advanced colorectal cancer.