Polypoid adenomyoma of the gastric fundus: an unusual endoscopic and pathologic presentation

Gastric adenomyoma (GA) is a rare benign lesion, most frequently found in the pyloric/antral region of the stomach. It consists of a mixture of smooth muscle and glandular structures, occasionally cystically dilated, lined by tall columnar epithelium, Brunner’s glands, and sometimes pancreatic parenchyma. In this report, we describe an unusual case of adenomyoma of the fundus of the stomach, which presented as a polyp on endoscopy, and was found to be a polypoid, cystic lesion pathologically; both of these features are rare for a gastric adenomyoma.