Detection of an Extramural Jejunal GIST by Video Capsule Endoscopy

Abstract

Purpose: Small bowel tumors are a rare cause of gastrointestinal malignancies. Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the GI tract and typically present in the stomach. Up to 20% can present in the small bowel. Most GISTs are located intramurally; however, 20% are considered extramural, occurring as exophytic masses protruding through the serosa. We report the case of obscure gastrointestinal bleeding secondary to an extramural jejunal GIST detected by capsule endoscopy. A 57-year-old woman presented to an outside hospital with anemia and melena. An upper endoscopy and colonoscopy were normal. Capsule endoscopy demonstrated a large, cratered ulcer in the mid small bowel. A repeat capsule endoscopy several weeks later was thought to indicate healing as the ulcer was no longer seen on captured images. She remained asymptomatic until 8 months later, when she presented to our institution with melena and anemia. Given the previous small bowel ulceration, an anterograde single balloon enteroscopy (SBE) was performed and found to be normal. A capsule endoscopy was then pursued showing abnormal vascular mucosa with ulceration in the mid small bowel beyond the insertion point of the SBE. A retrograde approach was unsuccessful at reaching the lesion. She was taken to the operating room, where a laparoscopically-assisted enteroscopy revealed a 5.5-cm extramural jejunal mass with intraluminal extension as the cause of the ulceration seen endoscopically. Pathology confirmed a GIST of spindle cell type, mitotic rate 3/50 hpf and margins free of tumor. She has remained asymptomatic following successful surgical resection and is to be evaluated by Oncology. GISTs may arise in the gastrointestinal tract anywhere from the esophagus to the rectum. In over 90% of cases, a tyrosine kinase receptor protein (CD117) is expressed. The median age at diagnosis is 63 years. The most common presentation is GI bleed, though patients may present with abdominal pain, early satiety, bloating, obstructive jaundice, and dysphagia. Most GISTs are submucosal in origin. Subserosal lesions and extra-intestinal lesions are also seen, though less commonly. Submucosal tumors are more easily detected by capsule endoscopy due to luminal impingement and overlying ulceration. Capsule endoscopy is limited in its ability to detect extramural GISTs unless there is extension to the lumen. CT scan is useful for diagnosing GISTs with extramural growth. Surgical resection is the standard therapy for non-metastatic GISTs. Our case illustrates that extramural mass lesions may present as mucosal ulcerations on video capsule endoscopy.