[Malignant carcinoid that developed against a background of chronic gastric ulcer].

A description of malignant carcinoid of alveolartrabecular structure developing in the edge of chronic progressive gastric ulcer is presented. Granules detectable by argirophilic method of Grimelius, toluidine blue after acid hydrolysis, and lead hemotoxylin were found in the cytoplasm of tumor cells. Changes in the epithelium of the type of cancer in situ as well as marked hyperplasia of argirophilic cells were observed in gastric mucosa in the edges of the ulcer. Although this observation may be interpreted as a peculiar variant of Zollinger-Ellison syndrome, it is more likely that this is a malignized chronic ulcer with carcinoid differentiation of the tumor tissue.