Pathological structure under microscope
The surface of the tumor was the duodenal mucosa, with columnar brush border cells, scattered goblet cells, Panes cells and the intrinsic glands of the duodenal mucosa. There were focal infiltration of lymphocytes and scattered eosinophils in the stroma of the lamina propria, accompanied by hyperemia and edema, and telangiectasis. The duodenal glands showed adenomatous hyperplasia at the base of the lamina propria and the submucosa, which were surrounded by mucosal smooth muscle fibers and divided into lobules. The glandular epithelium was well differentiated without atypia. At the base of the tumor, there were proliferating collagen fibrous connective tissue.(Fig. 2)
The specific gastric and intestinal epithelial immunohistochemical markers were further examined, such as MUC2, CD-X2, villin and AB-PAS staining. The results suggested that the tumor originated from the mucosa of the duodenum, rather than intestinal metaplasia of the gastric mucosa.(Fig. 3)