Identification of nonfamilial MSI-H colorectal cancer based on clinicopathological features / 基础医学与临床

ABSTRACT

Objective To identify clinicopathological features of high MSI (MSI-H).Methods We enrolled 150 patients,standard microsatellite loci (BA T25,BA T26,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 cancer with specific pathological features,Clinicopathological features can efficiently identify MSI-H colorectal cancers.