Neuroendocrine cells in gastric adenoma

Abstract

Gastric adenomas are recognised precursor lesions of gastric adenocarcinoma. We investigated biopsy material from gastric adenomas of 30 patients for the expression of potential cell growth promoting or inhibiting neuroendocrine mediators. In one patient an additional adenocarcinoma was diagnosed. Sections were stained for chromogranin (CG), serotonin (5-HT), progastrin (PG), glicentin (GLIC), pancreatic polypeptide (PP), Glucagon (GLUC) and somatostatin (S). In all cases neuroendocrine cells were demonstrated after staining for CG except in one case where only little biopsy material had been obtained. CG positive cells were predominantly found in the basal portions of the adenomas. Immunoreactive cells for 5-HT were the most prevalent cell type followed by cells staining for GLIC. PP, S and PG immunoreactive cells were only occasionally encountered. PG was also seen in mucous glands underlying adenomas where they appeared to be increased in some cases. Cells positive for GLUC were not observed. Intestinal metaplasia mainly of the incomplete type could be recognised in the majority of biopsies adjacent to the adenoma. In the one case of carcinoma neuroendocrine cells positive for CG, 5-HT and GLIC were present at the margin but not within the tumour. 5-HT has been shown to promote division of a wide variety of cell types. GLIC also possesses a trophic action. Both 5-HT and GLIC are found in gastric intestinal metaplasia. However, 5-HT occurs in gastric carcinoma where GLIC is absent. Gastrin-like peptides are recognised autocrine growth factors. The study shows endocrine cell proliferations to be a common phenomenon in gastric adenomas but reported to be less prevalent in carcinomas. Their product may regulate a more controlled growth in adenoma in contrast to the uncontrolled proliferation of carcinoma.