Simultaneous polypoid tumors of the stomach and duodenum with composite cell population (mucous, argyrophil, and lysozyme-containing cells): a case report.

Seventeen years after a Billroth II gastric resection for duodenal ulcer had been performed, two large polypoid tumors were found in the gastric stump (outside the stomal area) and in the duodenal stump of a 69-year-old man. Histologically the neoplasms were tubular adenomas with small focal carcinomatous changes restricted to the gastric tumor. A distinctive feature of both tumors was the occurrence of three major cell populations segregated into two different types of neoplastic epithelium: one with columnar mucous cells containing gastric type mucins and mixed with a large number of argyrophil endocrine cells and the other with large, pleomorphic cells containing immunoreactive lysozyme and intestinal type mucins. In the absence of any evidence of generalized gastrointestinal polyposes, it is suggested that both tumors originated from the gastric mucosa (of heterotopic origin in the duodenum) and that the second type epithelium may represent a particular, and up to now unrecognized, type of intestinal metaplasia.