[Mucus-forming apudoma of the stomach]

Gastric apudoma (argyrophilic carcinoma) some cells of which are characterized by intensive production of intestinal mucosa is described. Endocrine granules were found in the cytoplasm of the tumor cells, including mucosa-producing ones, by means of diagnostic APUD-reactions (Grimelius method, staining with toluidine blue after acid hydrolysis, lead hematoxylin) and electron microscopy. In the opinion of the authors, mucosa production indicates the entodermal nature of the tumor which casts doubt on the conception of the common neuroectodermal origin of all apudomas.