Comparative assessment of the mucosa of index segments of the colon in colorectal cancer

The aim of the study was to compare the incidence of colorectal cancer between colon segments and the molecular genetic characteristics of the mucosa of index colon segments. Materials and methods: A comprehensive retrospective study of 7,185 colonoscopies was conducted. A prospective study (2022-2023) of the colonic mucosa was performed in 152 patients with CRC. Results: An assessment of the CRC frequency by colon segment from all detected CRC cases revealed a predominance of the sigmoid and rectum, consistent with existing data. However, an analysis of the CRC frequency among all neoplasms in a specific colon segment revealed a predominance of the cecum, sigmoid, and rectum. An assessment of the differences in these indicators revealed unexpected discrepancies for the cecum, ascending colon, and descending colon. Mucosal morphometry revealed increasing differences in measurement parameters from the ascending colon to the sigmoid colon. Molecular genetic characteristics of the index segments for some of the studied parameters showed significant differences both between colon segments and between colon halves. However, among colon segments, there was heterogeneity in parameters that was inconsistent with the combined assessment of the colon halves. Conclusion: In colorectal cancer, there is morphological and genetic heterogeneity in the mucosa between different segments of the colon, which is not consistent with the differences in CRC incidence between the right and left halves of the colon. The identified differences between the outer colon and the colonic segments require further evaluation.

colorectal cancer, colon, mucosa, molecular genetic characteristics, mucosal morphometry

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