S4750 An Elusive Small Bowel GIST in an Atypical Patient

Introduction: Gastrointestinal stromal tumors (GISTs) are rare mesenchymal tumors that may arise throughout and around the gastrointestinal (GI) tract with median age of diagnosis between 65-69 years. We present a case of an otherwise healthy 43-year-old man presenting with intermittent melena, eventually found to have a jejunal GIST. Case Description/Methods: A healthy 43-year-old man presented with intermittent melena and iron deficiency anemia. Upper endoscopy and colonoscopy were unrevealing. He presented again with melena at which time push enteroscopy was also unrevealing. A capsule endoscopy revealed active proximal small bowel bleeding approximated to the distal duodenum, thus a repeat push enteroscopy was conducted. This revealed a proximal jejunal ulceration that was just out of reach of the endoscope. A hemostatic clip was placed near the lesion. Finally, a double-balloon enteroscopy identified a 2.5–3.0 cm ulcerated jejunal mass. Biopsy revealed bland spindle cells. Immunostaining revealed positive DOG1 and CD117 and negative desmin stain, all consistent with a GIST. Computed tomography abdomen/pelvis did not reveal metastatic disease. In a subsequent encounter, he again developed melena requiring admission, red blood cell transfusions and urgently underwent a laparoscopic small bowel resection of a 3.0 cm grade 1 GIST. He is doing well at follow-up without anemia or further episodes of melena. Discussion: GISTs account for 0.04% of all GI tumors and typically present in older adults. GISTs are found in the stomach (60%), small intestine (30%), and rarely in the esophagus, colon, rectum, or outside of the GI tract. Metastatic disease is present at diagnosis in 10-20% of cases. They may lead to significant GI bleeding. Our patient suffered through multiple episodes of melena requiring multiple admissions and blood transfusions over the course of weeks-to-months while the above diagnostic evaluation took place. This case highlights the importance of recognizing that GISTs may occur in younger adults or even children and may cause life-threatening GI bleeding. A higher index of suspicion and more aggressive initial diagnostic approach may have resulted in decreased morbidity prior to ultimate curative resection.