Value of immunohistochemistry to evaluate the degree of malignant transformation of villous tumors
Science Articles / / August 12, 2017
Igumenov AV S.V.Petrov., Gatatullin IG Gannoshenko EM
City Clinical Hospital №1, Tolyatti
Kazan State Medical University, Kazan State Medical Academy
Hitherto unresolved issues early diagnosis of colorectal villous tumors, reliable detection of malignant transformation and a common approach to treatment.Obviously, this circumstance can be explained by a certain percentage of discrepancies in the results of the preoperative examination of patients with large tumors and villous morphology studies of remote tumors.Thanks to advances in biochemistry and molecular biology at the present time in the arsenal of researchers and clinicians have a huge number of biologically significant indicators that may help in the diagnosis of early colorectal cancer arising in the background of villous tumors and, therefore, in choosing the adequate treatment.Fundamentally new possibilities of using antibodies as the most sensitive available today markers of biological cells and their components.
aim of the study: Identify the value of tissue biomarkers p53, Ki-67, CEA to evaluate the degree of malignant transformation of villous tumors.
Materials and methods: 43 drug villous adenomas of the colon were subjected to immunohistochemical studies include a study of expression of carcinoembryonic antigen using a mAb clone 12-140-10 (Novocastra company, UK) to a protein CD 66e or carcinoembryonic antigen(CEA), p53 oncoprotein using mAb clone D07 (Novocastra firm) to a mutant protein gene - suppressor p53 and Ki-67 marker of proliferation using mAb clone MIB-1 (manufactured by DakoCytomation, Denmark) to the nuclear protein Ki-67.In an imaging system using sets LSAB2 (DAKO) and Novostain (NovoCastra).As negative control sections were incubated with normal serum of the animal from which the first antibody with PBS and were obtained.It served as a positive control a normal mucosa tissue, as well as tissue localization of various carcinomas (breast, stomach, lung).
results. antibodies to CEA villous polyps stained with only the apical part of the villi epithelium.In porsinchatyh polyps average index Ki-67 (the number of positively stained cells) was 5,5 ± 0,38%.When dysplastic changes in the epithelium proliferation intensity intensified, and proliferation index was 12.1 + 0.45%.Expression of mutant p53 gene was negative and positive in 8 of 35 observations villous polyps.Ki-67 -positive tumor cell nuclei were found in all neoplastic cells, glands, regardless of the degree of differentiation.Average Ki-67 index in the tumor was 62,5 ± 2,78%.Carcinoembryonic antigen in 80% of cases detected in cells strongly, moderately to 20% .In the vast number of observations colorectal cancer - 80% - found bright expression of a mutant protein of the p53 gene.The reaction was characterized by uniform staining of the nuclei of tumor cells and does not depend on the degree of differentiation of the tumor.
Conclusions. mutation of the p53 gene indicates the transition villous adenoma colon cancer;Expression of CEA is directly proportional to the degree of differentiation of colorectal villous tumors;with dysplastic changes in the epithelium of villous adenomas increases the intensity of proliferation (Ki-67 index).