COMPARATIVE ANALYSIS OF CD44 EXPRESSION IN POLYPS AND ADENOCARCINOMA OF DISTAL COLON

Introduction. CD44 is one of the most used markers of cancer stem cells in colorectal cancer. Even though, the questions of its diagnostic and prognostic value remain open. The aim of the study was to compare CD44 immunohistochemical expression levels in polyps and adenocarcinoma of the distal colon. Materials and methods. Histopathological and immunohistochemical studies of biopsies from 40 patients and surgical material of colorectal adenocarcinoma from 30 patients were carried out. Results. It was figured out that distal colonic polyps are characterized by membranous CD44 expression with the medians of relative areas of CD44+ cells equal to 60,24 (50,22; 70,22) % stromal cells and 15,67 (12,47; 19,47) % epitheliocytes. Colorectal adenocarcinoma is characterized by membranous-cytoplasmic CD44 expression with the medians of relative areas of CD44+ cells equal to 61,26 (42,58 ; 79,15) % stromal cells and 30,60 (24,56 ; 36,45 ) % cancer cells. Comparative analysis of the data obtained for the pTNM stages of colorectal adenocarcinoma revealed some significant differences. The median of CD44+ stromal cells area on the I stage equals to 31,41 (19,87 ; 42,15) % vs. the median of CD44+ stromal cells area on the II stage equals to 48,26 (35,44 ; 61,45) % , р ˂ 0,05; the median of CD44+ stromal cells area on the II stage vs. the median of CD44+ stromal cells area on the III stage equals to 78,36 (61,13 ; 80,06) % , р ˂ 0,05. The median of CD44+ cancer cells area on the III stage equals to 30,35 (21,19 ; 35,47) % vs. the median of CD44+ cancer cells area on the IV stage equals to 31,25 (30,22 ; 41,19) % , р ˂ 0,05. Moreover, it was revealed that the median of CD44+ epitheliocytes area in polyps two-fold smaller than the median of CD44+ cancer cells area in colorectal adenocarcinoma: 15,67 (12,47 ; 19,47) % vs. 30,60 (24,56 ; 36,45 ) % , р ˂ 0,05. Conclusions. Distal colonic polyps are characterized by membranous CD44 expression with the median of CD44+ epitheliocytes area that is two-fold smaller than the median of CD44+ cancer cells area. Colorectal adenocarcinoma is characterized by membranous-cytoplasmic CD44 expression with the median of CD44+ stromal cells area that significantly increases during the tumor progression from I to III stages and with the median of CD44+ cancer cells area that significantly go up during the tumor progression from III to IV stages.