根据临床病理学特征鉴别无家族史MSI-H大肠癌

Identification of nonfamilial MSI-H colorectal cancer based on clinicopathological features

目的根据修订的Bethesda指南,分析无家族史大肠癌患者的病理学特征和微卫星不稳定检测结果的关系,探讨无家族史高度微卫星不稳定(MSI-H)大肠癌的临床病理学特征。方法纳入150例无家族史大肠癌患者,选取5个标准位点(BAT25、BAT26、D2S123、D5S346、D17S250)进行免疫荧光PCR,以GeneMapper软件分析PCR产物;收集患者年龄、性别及肿瘤部位信息;光学显微镜观察多种病理特征(分化程度、黏蛋白分化、组织学异质性及类Crohn反应);免疫组化方法检测肿瘤浸润淋巴细胞CD4+和CD8+的表达。Logistic逐步回归分析产生回归方程,依据病理特征计算MSI-H表型的概率。结果无家族史大肠癌中MSI-H表型为13.33%;低分化、组织学异质性、类Crohn反应和TILs是MSI-H表型大肠癌的独立鉴别因子,Logistic回归方程鉴别MSI-H表型大肠癌的敏感性为70.0%,特异性为99.2%,总准确率为95.3%。结论MSI-H表型构成了一个病理学特异的无家族史大肠癌类型,根据临床病理学特征能够有效地检出MSI-H表型大肠癌。

Objective To identify clinicopathological features of high MSI （MSI-H）.Methods We enrolled 150 patients,standard microsatellite loci （BAT25,BAT26,D2S123,D5S346,D17S250） were amplified by polymerase chain reaction（PCR）with fluorescent primers,and the PCR products were analyzed by GeneMapper software;age at diagnosis,gender and site were obtained;various pathological features were observed by light microscopy;the expression of tumor infiltrating lymphocytes（CD4＋ and CD8＋） was detected by immunohistochemistry.Using a stepwise logistic regression model,a formula was generated that could be used to calculate the probability of a colorectal carcinoma being MSI-H based on pathological features.Results Among 150 cancers,MSI-H was 13.33%.Independent identifiers inclucle poor differentiation,histologic heterogeneity,Crohn＇s-like reaction and tumor-infiltrating lymphocytes,logistic regression formula shows a sensitivity of 70.0% and a specificity of 99.2% and a accurate ratio of 95.3% for MSI-H.Conclusion MSI-H phenotype cancer is a type of nonfamilial colorectal cancerwith specific pathological features,Clinicopathological features can efficiently identify MSI-H colorectal cancers.