Mucoepidermoid carcinoma of the stomach.

A rare case of mucoepidermoid carcinoma of the stomach in a 70-year-old man is reported. The protruded mass with central depression resembled a submucosal tumor, located on the posterior wall of a part of the cardia, fornix, and upper corpus. Histologically, submucosal ectopic glands composed of columnar cells, mucus-producing cells that closely resemble gastric epithelium, and ciliated epithelium were observed. The tumor consisted of an admixture of cuboidal, columnar cells, mucus-producing cells, singled or pseudostratified ciliated epithelium, and squamous metaplastic cells. The tumor cells were intimately continuous with the submucosal ectopic glands. Gradual transition between tumor cells and epithelium of submucosal ectopic glands was recognized. It is supposed that mucoepidermoid carcinoma of the stomach in this case derived from preexisting submucosal ectopic mucous glands of the stomach.