Frequency of cancerous and precancerous epithelial lesions in the stomach in different models for enterogastric reflux.

A gastroenterostomy without entero-anastomosis in rats favours the development of adenomatous epithelial lesions at the gastroenteral borderline in dependence of exposition to MNNG. The extent of such changes in the mucosa could be modified by vagotomy, pyloroplasty, or the prevention of duodenogastric reflux (Roux-en-Y method), whereby vagotomy has an enhancing effect on proliferation. A comparison of the mucosal changes at the gastroenteral anastomosis indicates that a multitude of factors causes environmental changes at the gastroenteral borderline, stimulating epithelial proliferation to the point of cancer formation. Thus, it is not possible to accuse any single factor such as intestinal reflux, carcinogens or different surgical techniques as the sole culprit in carcinogenesis.