Heterotopic pancreas in the stomach is usually asymptomatic and benign. Here, we presented a rare case of an early gastric cancer overlying a heterotopic pancreas. A 48-year-old woman underwent esophagogastroduodenoscopy, which revealed a subepithelial mass measuring 2.0×1.5 cm on the gastric antrum with a 1-cm erosive erythematous discoloration on the surface. A biopsy specimen showed moderately differentiated tubular adenocarcinoma. Endosonography showed a heterogeneous hypoechoic mass measuring 1.3×0.6 cm, with indistinct margins in the second and third layers of the gastric wall; anechoic tubular structures within the mass were suggestive of heterotopic pancreas. Distal gastrectomy was performed, which confirmed an early gastric cancer confined to the mucosa, and a separate underlying heterotopic pancreas. Although heterotopic pancreas is most likely benign, careful endoscopic observation of the mucosal surface is necessary to avoid overlooking a coincident early gastric cancer.
Keywords: Early gastric cancer; Ectopic pancreas; Endosonography; Heterotopic pancreas.