Expression Of Ki-67and MCM₂and Its Significance In The Carcinogenesis Of Ampullary Adenoma

Objective:At present, scholars,home and abroad,agreed that the processof adenomatous carcerous changes of colon,gallbladder and stomach was inline with the evolution of the"adenoma-Epithelial neoplasia-adenocarcinoma".The study on adenomatous carcerous changes of duodenal ampulla was few.Some scholars abroad agreed that the process of adenomatous carcerouschanges of duodenal ampulla were similar to the process of colorectaladenoma.It was difficult to diagnose the nature of the ampullary tumor beforesurgery because of the complexity and anamorphosis of the tumorigenesisprocess. The most common method was endoscopic biopsy. However, it wasnot easy to rule out preli minary cancer even though the pathological diagnosisis benign.Ki-67and MCM₂were frequently used as the proliferation-associatedantigens in recent years. Ki-67and MCM₂were likely to be the biologicalindexs which can identify the malignant tumor earlier, evaluate the potential ofpremalignant lesions evolving into malignant, and screen the high risk groupsof population. The objective of this study was to detect the expression ofKi-67and MCM₂protein in ampullary adenoma epithelial neoplasia andcancer change, and investigated the value of early diagnosis in ampullaryadenoma cancer and the significance guiding clinical treatment detectonby combining Ki-67with MCM₂.The methods were the pathomorphology,immunohist-ochemistry and flow cytology.Method:In the subject,the263paraffin-embedded archival wax blocks of Vatertumors cuted by duodenoscopes came from Pathology Department ofB-ethune International Peace Hospital, collected from February2001toOcto-ber2011. All the sections were classified in accordance with thediagnos-tic criteria of WHO (2003), and the diagnosis were classified by two senior pathologist. We took47cases of ampullary adenoma with epithelialneoplasia of low grade,29cases of ampullary adenoma with epithelialneoplasia of high grade,27cases of ampullary adenocarcinoma, and20casesof normal ampullary tissues as the control group.The expression of the Ki-67and MCM₂protein were detected by immunohistochemical SP method,meanwhile the results were statistically analyzed whether there was astatistically significance, and analyzed whither there was a correlation bettwenthe age, gender and the two indexs.3cases of ampullary adenoma withepithelial neoplasia of low grade,3cases of ampullary adenoma with epithelialneoplasia of high grade,3cases of ampullary adenocarcinoma, and3cases ofnormal ampullary tissues as the control were minced and subjected tocollagenase to obtain single cell suspension.We detected the expression ofKi-67by the way of flow cytometry, and analyzed whether there was astatistically significant between groups. The data (mean±standard deviation)were analysised by using SPSS13.0statistical analysis software.Comparedeach group of count data and measurement data. Bilateral inspection P<0.05was considered significant differences.Results:1. The immunohistochemical results showed that, the expression of Ki-67and MCM₂in the process of ampullary adenoma gradually increased; therewas a significant difference(P<0.05)among the ampullary epithelial neoplasiaof low grade group, ampullary epithelial neoplasia of high grade group andadenoma with canceration group. Application of paired t-test, there was astatistical difference between the proliferation index of Ki-67andMCM₂(P=0.000). While there was no significant difference (P>0.05) betweenthe Ki-67and MCM₂of each group.2. Flow cytometry analyzed Ki-67was expressed in ampullary epithelialneoplasia of low grade group, ampullary epithelial neoplasia of high gradegroup,adenoma with canceration group, and normal ampullary tissues group.There was significant difference between any two above-mentionedgroup(P<0.05). Conclusion:1. In the process of ampullary adenoma cancerous change, the proliferationindex of Ki-67and MCM₂increased gradually. It reflect that the proliferationindex of Ki-67and MCM₂could reflect cell proliferation, which could ascandidate maker for ampullary early carcinoma.2. In the process of ampullary adenoma cancerous change, MCM₂ascandidate maker for cell proliferation was superior than Ki-67.3. Ampullary adenoma was disease tending to carcinomatous change.