ADENOCARCINOMA IN HETEROTOPIC GASTRIC PANCREAS

Abstract

A 67-year-old man entered our hospital complaining of anorexia and nausea. Roentogenograms showed a smooth elevated lesion in the prepyloric region and deformity of the duodenal cap (Figure 1). Gastrofiberscopic examination revealed a submucosal mass in the posterior wall of the antrum (Figure 2). Selective gastroduodenal arteriography showed a hypervascular area and a tumor stain (Figure 3). An operation was performed because of progression of the symptoms. On the resected specimen, a submucosal mass, measuring 3.0×3.0×3.0 cm, was found in the posterior wall of the gastric antrum. On microscopic examination, the tumor located in the submucosal and proper muscle layer of the antrum and was composed of well-differentiated ductal structures lined by a single layer of dysplastic cuboidal epithelium. The tumor was mixed with heterotopic pancreatic tissue which consisted of acinar and ductal tissue. The overlying gastric mucosal layer was normal. A diagnosis of adenocarcinoma originating from the heterotopic pancreas in the stomach was made. Carcinoma arising in heterotopic gastric pancreas is extremely rare and only 15 cases including ours were reported in Japan. They located in the antral region of the stomach in most cases. Histologically, tubular adenocarcinoma was common. It appears that careful histological examination is necessary for evaluation of histogenesis of such carcinomas.