[Fibroma of the small intestine with heterotopia of the pyloric glands in the mucous membrane covering the tumor].

Small bowel tumour, 5 X 3 X X 3 cm in size, in a woman of 52 provoked intestinal invagination. Small bowel was resected with the tumour which was diagnosed histologically as a soft fibroma. Focal areas of the pyloric glands with single argyrophil endocrine cells as well as "stomach metaplasia" of the epithelium of one crypt were detected in the intestinal mucous membrane covering tumour. In the author's opinion, this heterotopia is related to the developmental malformation.