The Development of Gastric Outlet Obstruction due to a Lumen-occupying Protruding Duodenal Ulcer Mimicking a Submucosal Tumor.

Even in the era of Helicobacter pylori eradication and proton pump inhibitors, peptic ulcer remains an important disease. Stricture due to a duodenal ulcer in the healing stage is a well-known etiology of benign gastric outlet obstruction. However, a duodenal ulcer-induced submucosal tumor-like change with gastric outlet obstruction is a very rare manifestation. We herein present a rare case of a patient with deteriorating symptoms of gastric outlet obstruction caused by an unusual manifestation of a lumen-occupying protruding duodenal ulcer mimicking a submucosal tumor.