The experimental production of precancer and cancer of the stomach

Abstract

The pancreatico-duodenal vein was ligated in albino rats simultaneously with the introduction of a paraffin capsule with 9,10-dimethyl-1,2-benzanthracene into the anterior wall of the pyloric region of the stomach. Thickenings and mucosal nodules of various size were observed at the site of administration; histologically they represented heterotopic proliferations of the glandular epithelium penetrating to different depths, even to the serous membrane. Notwithstanding the cancerogen elimination, arrest of inflammation and absence of necroses, heterotopic proliferations persisted in the submucosa in the form of foci of adenomatous structure, characterized either by a multiformity of glandular cells, or by a prevalence of one of the generations of atypical glandular elements. Activation of growth of the glandular foci exhibiting a marked destructive and infiltrating nature of growth and a high mitotic activity at late experimental periods (in 16–18 months) points to the malignant nature of these proliferations. Thus, by employing an additional factor for changing the functional state of the organ, the possibility of inducing malignant epithelial proliferations of the adenocracinoma type by means of 9,10-dimethyl-1,2-benzanthracene was demonstrated for the first time. The rumen was always devoid of any alterations.