Immunohistochemical Aspects of the Expression of Markers of Cell Cycle Regulation, Proliferation and Apoptosis (p53, Ki-67, bcl-2, cyclin D1) in Breast Neoplasia

Abstract

The aim of study was to develop new criteria for the differential diagnosis of variants of intraepithelial neoplasia of the accessory lobe of the mammary gland based on the use of a comprehensive morphological research method using an optimal panel of markers to improve the quality of diagnosis and estimation the risk of invasive cancer development. Introduction. To date, the pathology of the mammary glands occupies a leading position in the structure of oncological diseases and continues to grow from year to year. Currently, a three-level characteristic of the degree of tumor differentiation, common for oncological pathomorphology, is widely used to determine the malignant potential of preinvasive lesions of the mammary gland and its lobes. Material and methods. The results of a retrospective examination of 182 patients with mammary gland accessory lobe cancer treated at our Center from 2010 to 2020 were included to our research. The patients were divided into 4 groups according to the results of the morphological study. Results. Expression of p53 was least common in patients with dysplasia, lobular and highly differentiated intraductal, making up 1.6%, 3.5% and 14.7%, respectively. The study of cyclin D1 expression showed that among patients with intralobular, intraductal carcinomas and intraductal carcinoma in situ with the onset of invasion, it was observed equally (64.3%, 66.2% and 69%, respectively). Comparison of the apoptosis marker bcl-2 expression values showed that this indicator was most often detected in patients with intralobular carcinoma and highly differentiated intraductal carcinoma (85.5%, 89.3% and 87.5% of cases). Estimation of Ki-67 expression values showed that it was most common in patients with poorly differentiated intraductal carcinoma and patients with microinvasive cancer, the values of the indicators were 24.3% and 50%, respectively. Conclusion. The discovered trend allowed us to propose this set of immunohistochemical markers as additionally characterizing the ability of intraductal carcinoma to further progress into invasive mammary gland accessory lobe cancer. The data obtained on the basis of immunohistochemical studies on the frequency and severity of expression of various immunohistochemical markers provide a basis for determining the individual prognosis of the course of the disease, which, in turn, will contribute to the development of adequate treatment regimens for preinvasive breast neoplasia.