Pathology of endocrine cells in gastric mucosa.

Pathological changes of gastric endocrine cells are reviewed. The lesions are subdivided according to the type of mucosa in which they originate. Hyperplasias of fundic endocrine cells, probably related to the patient's concomitant hypergastrinemia, were found in Zollinger Ellison syndrome and in chronic atrophic gastritis. They may evolve into carcinoid tumors. Typical and atypical forms of fundic carcinoids have been described, usually without specific clinical syndrome. Antral gastrin G cells proliferate in achlorhydric, hypergastrinemia patients while their involvement in peptic ulcer disease is probably limited to a minority of cases. Antral gastrin secreting tumors are rare. Metaplasic intestinal epithelium also harbors endocrine cells that may present hyperplastic and neoplastic changes.