A novel subtyping of intestinal metaplasia of the stomach, with special reference to the histochemical characterizations of endocrine cells.

Intestinal metaplasia of the stomach was grouped into 3 subtypes (A, B and C) according to the degree of pyloric gland involution which was judged from patterns of paradoxical Concanavalin A staining after Katsuyama and Spicer. The appearance of endocrine cells was investigated with immunohistochemical and silver methods. Type A metaplasia with slightly to moderately atrophic pyloric glands corresponded to the incomplete type in the previous classification, while Type C showing complete disappearance of pyloric glands corresponded to the complete type. Type B with severely atrophic pyloric glands was an intermediate. This subtyping reflects the cell kinetics in the intestinalized mucosa well. Regarding the endocrine cells, their total number varied in the order Type A greater than Type B greater than Type C. The selective populations of the endocrine cells including glicentin-containing cells, Grimelius-positive argyrophil cells without argentaffinity and intestinal-type enterochromaffin cells frequently formed hyperplastic foci in the intestinalized areas, where the other gut-type and proper gastric-type endocrine cells were scarcely noted. Immunoreactivity of glucagon or bovine pancreatic polypeptide were occasionally identified in a subpopulation of the glicentin-containing cells.