微卫星不稳定性对R0切除高危Ⅱ结肠癌辅助化疗后的预后意义

Significance of microsatellite instability in patients with R0 resection and high-risk Ⅱ stage colon cancer after adjuvant chemotherapy

目的:探讨微卫星不稳定性与R0切除术后行辅助化疗的高危Ⅱ期结肠癌患者临床预后的关系,为结肠癌的个体化治疗提供依据。方法:选择47例高危Ⅱ期结肠癌患者,均行R0切除及5-氟尿嘧啶为基础的辅助化疗。应用显微切割联合聚合酶链反应及毛细管电泳技术检测和比较肿瘤细胞及其正常腺上皮细胞的微卫星状态,分析其不稳定性与患者临床病理特征及预后的关系。结果:高频微卫星不稳定性的发生率为36.17%(17/47),低频微卫星不稳定性为27.66%(13/47),微卫星稳定为36.17%(17/47)。高频微卫星不稳定性与患者的性别、年龄、肿瘤部位和肿瘤组织学分级无关。高频微卫星不稳定性表达与患者的无病生存期(P=0.298)、总生存期(P=0.667)无关。多因素Cox回归分析结果提示,低分化肿瘤组织学分级(P=0.003)、受检测的淋巴结数目<11个(P=0.027)是独立的预后不良因素。结论:对于R0切除的高危Ⅱ期结肠癌患者,高频微卫星不稳定性不能作为辅助化疗后的预后指标,肿瘤组织学分级和受检测淋巴结数目是独立的预后指标。

OBJECTIVE：To analyze significance of microsatellite instability in patients with R0 resection and high-risk Ⅱ stage colon cancer after adjuvant chemotherapy for individual treatment.METHODS： Forty-seven cases with R0 resection and high-risk Ⅱ stage colon cancer after 5-fluorouracil-based adjuvant chemotherapy were selected.Patterns of microsatellite were tested with laser capture microdissection combined with polymerase chain reaction and capillary electrophoresis in these cases.Correlation of microsatellite instability with clinical characteristics and survival of patients was analyzed.RESULTS： The incidence of high frequency microsatellite instability was 36.17%（17/47）,low frequency microsatellite instability 27.66%（13/47） and microsatellite stable 36.17%（17/47）.High frequency microsatellite instability was not associated with age,gender,tumor site and grade.High frequency microsatellite instability did not correlate with disease-free（P=0.298） and overall survival time of patients（P=0.667）.Cox analysis showed that poor-differentiated tumor grade（P=0.003） and less than 11 lymph nodes examined（P=0.027） were an independently poor prognostic factors.CONCLUSIONS： High frequency microsatellite instability will not be considered as a prognostic factor in patients with R0 resection and high-risk Ⅱ stage colon cancer after 5-fluorouracil-based adjuvant chemotherapy.Tumor grade and number of lymph node examined can be independently prognostic markers in these patients.