Objective: To detect and analyze the time-effect of expression of DNA mismatch repair (MMR) protein in colorectal cancer through immunohistochemical method and discuss the effective time of MMR detection in colorectal cancer specimens after operation.Methods: A total of 45 cases of colorectal cancer surgical specimens from January 2010 to December 2018 from the General Hospital of the Eastern Theater Command (formerly Bayi Hospital) were selected.Each case was set up with a positive control for MMR protein (MLH1, MSH2, MSH6 and PMS2), then immunohistochemical detection was perfomed. Results: In the case of normal expression of the positive control, the MMR protein immunohistochemical test showed that the specimens were weakly stained in 2010 and 2011, the specimens were weakened in 2012, and that the staining degree was basically the same from 2013 to 2018. Conclusion: The absence of MMR protein is closely related to the occurrence and development of colorectal cancer, and it is more effective to select pathologic wax slices within 8 years for immunohistochemical detection. |