The Problem of Vascularization of Precancerous Lesions of the Colon and Development of Hypoxia at the Incipient Stages of Blastomogenesis.

The features of the blood supply in the colon mucosa during the development of hyperplastic and dysplastic processes, and early neoplastic lesions were studied. The study cohort comprised the material of 92 patients of the N. N. Blokhin National Medical Research Center of Oncology collected during 2002-2016. The initial stages of hyperplastic, atypical processes developed against the background of enhanced angiogenesis. During the development of adenomatosis with concomitant dysplasia, the blood supply of newly formed structures decreased, which was associated with overexpression of markers of tissue hypoxia Hif1, CAIX, and Glut1. The expression of these markers was maximal in the foci of highly pronounced dysplasia, but was not detected in the foci of carcinoma in situ and microinvasion, when the cells reach the stroma with abundant vascular supply. It can be hypothesized that hypoxia forces the cells to search the territories with sufficient vascularization and migrate to other structures, which finally manifests in invasion and destruction of adjacent tissues and dissemination of these cells in the body (formation of metastasis).