Investigations of hyperplasiogenous gastric polyps by partial reconstruction

Four focal foveolar hyperplasias (hyperplastic polyps) and 41 hyperplasiogenous polyps were studied by serial sections and partial graphic reconstruction. Position of mitoses and the border between foveolar epithelium and glandular epithelium were recorded. The results show that the hyperplasiogenous polyp essentially is a hyperplasia of the gastric mucosa in which the foveolar epithelium always plays a major role. The zone of mitotic activity, especially the transitional zone between proliferating and differentiated cells, is widened. The glands usually show atrophy, but also may be normal or hyperplastic. An overaging of foveolar epithelia may contribute to development of erosions frequently seen. Splitting of the muscularis mucosa seems to be a secondary phenomenon which in turn may contribute to cystic dilation of foveolae. Because of its characteristics in structure and cell proliferation the term "hyperplasiogenous polyp" seems to be justified and preferable as compared to the term "hyperplastic polyp" (WHO-nomenclature; Oota, 1977).