Colorectal and Stomach Cancer, a New Look at the Features of Morphogenesis

Purpose of the study: to determine the reasons for the increase in the incidence of colon and stomach cancer, as well as the insuffi cient eff ectiveness of colon cancer screening and prevention programs.

Material and methods of research: clinical and endoscopic, most often annual studies of the colon in 4134 patients over a 15-year period with morphological assessment of the changes detected (more than 11,000 preparations); the method of esophagogastroduodenoscopy with biopsy of gastric tumors (113 studies); special methods of morphological studies, including electron microscopy, detection of hybrid cells; methods of vital chromo- and colonomicroscopy, including for prospective study of the structure of the mucous membrane in the zone of probable development of cancerous tumors during subsequent observations; the method of gastromicroscopy; a laboratory method for studying the concentration of carcinoembryonic antigen (CEA) in homogenates of tissues of the mucous membrane and cancerous tumors.

Research results: annual dynamic observations of patients for 15 years showed that development of sporadic cancer in the colon occurred in 3.4% of patients. In most of them (83.8%) cancer tumors appeared during annual intervals between observations without any visible connection with previous adenomas; we stated the absence of practical possibility to predict timing and localization of development of cancer tumors in them. Tumors with high growth rates appeared on the border between the epithelial surface with signs of moderate diff use hyperplasia (DH) and the epithelial surface of small adenomas (A) with moderate dysplasia of gland epithelium. It was established that in cases of rapid development of cancer adenoma and carcinoma are not consecutive stages of malignancy, but on the contrary – a synchronous process. This type of cancer tumors develops as a result of fusion (hybridization) of cells of hyperplastic epithelium and epithelium of adenomas. A more pronounced increase in the concentration of CEA in tumors compared to the surrounding mucous membrane confi rmed the embryonic origin of tumors of this type. Cells with morphological features of hybrids were also found in gastric cancer tumors.

Conclusion: A pathoembryonic theory is presented with a complete cycle of morphological changes, including the diversity of the structure of the surface epithelium in the colon and the discovery of hybridization of cells from adjacent diff erently structured epithelia as a biological mechanism leading to the initiation of cancer with high growth rates (similar changes were found in gastric tumors). It is also shown that tumors with slow growth rates in the colon are formed mainly from previous adenomas as they recur and the degree of dysplasia of the glandular epithelium increases in them in accordance with the generally accepted views on the process of carcinogenesis in the colon. Known promoters of hybridization of epithelial somatic cells include polyethylene glycol, which is widely used in medicine, as well as in the food industry; there is reason to believe that a signifi cant part of such substances (fusogens) have not been identifi ed to date. A number of signs suggest that hybrid cells also play a signifi cant role in the metastatic process.