微卫星不稳定散发性大肠癌的临床病理特征和DNA倍体研究

目的:探讨微卫星不稳定的散发性大肠癌的临床病理特征及微卫星不稳定表型和DNA倍体类型的关系。方法:对71例散发性大肠癌行BAT25和BAT26两个位点的微卫星不稳定检测和流式细胞术倍体分析,探讨微卫星不稳定状态和临床病理特征及DNA倍体类型的关系。结果:微卫星不稳定的阳性率为9.86%(7/71),微卫星不稳定表型和发病部位、组织学类型及分化程度相关(P<0.05),而与性别、年龄、淋巴结转移和分期无关。微卫星不稳定的散发性大肠癌中右半结肠癌和低分化腺癌的比例高于微卫星稳定者。68例患者检出二倍体和异倍体分别为18和50例,微卫星不稳定表型者5例为二倍体,因此和DNA倍体类型显著相关(P=0.012)。结论:微卫星不稳定的散发性大肠癌好发于右半结肠,具有低分化腺癌的倾向,多为二倍体。

Clinicopathologic features and DNA ploidy of sporadic colorectal cancers with microsatellite instability

Purpose:To explore the clinicopathologic features of sporadic colorectal cancer patients with microsatellite instability(MSI) and the correlation between the microsatellite instability and the DNA ploidy.Methods:Detecting microsatellite instability with two sites(BAT25 and BAT26),conduct flow cytometry to analyze the DNA ploidy among 71 sporadic colorectal cancer patients and probe into the relationship between the microsatellite instability phenotype and the clinicopathologic characteristics as well as the DNA ploidy.Results:The positive rate of the microsatellite instability among sporadic colorectal cancer patients was 9.86 percent.The microsatellite instability phenotype was correlated with the tumor site and the histopathologic type and the differentiation grade with the P value less than 0.05,while it was independent of the gender,age,lymph node metastasis and Dukes' stage.The proportion of right colon cancers and poorly-differentiated adenocarcinomas of sporadic colorectal cancers showing microsatellite instability was higher than that of microsatellite stable ones.18 and 50 cases showed diploidy and aneuploidy respectively.5 cases of MSI were diploid,There was statistically significant correlation between the microsatellite instability phenotype and the DNA ploidy(P=0.012).Conclusions:Sporadic colorectal cancers with microsatellite instability were prone to occur in the right colon and to be poorly-differentiated adenocarcinomas and inclined to be diploid.