A CASE OF EARLY CANCER SUSPECTED TO ARISE FROM HETEROTOPIC GASTRIC MUCOSA IN THE HORIZONTAL PORTION OF THE DUODENUM

Abstract

A man in his 60's was admitted to our hospital after being diagnosed with duodenal cancer. Upper gastrointestinal endoscopy showed an elevated lesion of 15 mm diameter in the horizontal portion of the duodenum, which was accompanied by several elevated reddish lesions in the duodenal bulb and descending portion. The elevated lesion in the horizontal portion and some of the other lesions had depressed areas on their surfaces. A biopsy of the elevated lesion in the horizontal portion identified a well-differentiated adenocarcinoma and that of one of the elevated lesions in the duodenal bulb identified heterotopic gastric mucosa with inflammation. We resected the lesion in the horizontal portion by endoscopic mucosal resection (EMR). Histopathological analysis revealed an adenocarcinoma confined to the mucosal layer that was adjacent to the heterotopic gastric mucosa. The gastrointestinal endoscopy and histopathology suggested that the duodenal cancer arose from the heterotopic gastric mucosa. Duodenal cancer with heterotopic gastric mucosa in the horizontal portion is considered to be rare. We report the case and review the relevant literature.