A Case of Duodenal Gastrointestinal Stromal Tumor Mimicking Isolated Duodenal Varix

Gastrointestinal stromal tumors (GIST) are generally located in the stomach and small intestine, and they present most with commonly abdominal pain. However, the duodenum is an unusual location and is commonly associated with gastrointestinal bleeding. A 51-year-old female was admitted for a 15-day history of melena and malaise. A cystic mucosal lesion featuring an isolated duodenal varix was observed by gastroduodenoscopy. Abdominal CT revealed a tortuous vascular structure at the posterior wall of the duodenum. Endoscopic Histoacryl injection therapy at the cystic mucosal lesion and a duodenal segmental resection were performed. The procedure was successful. Microscopic observation revealed GIST. We report a case of a duodenal GIST mimicking an isolated duodenal varix.