P2054 - Extragastrointestinal Stromal Tumor Arising From the Omentum Presenting as Hematochezia

Nathan DeRon, DO¹, Huda Khan, MD^2
1Methodist Health System of Dallas, Dallas, TX; ²Methodist Dallas Medical Center, Dallas, TX

Introduction: Gastrointestinal stromal tumors (GISTs) are neoplasms arising from the bowel wall, most often in the small intestine, but rarely may arise from extragastrointestinal locations. These tumors rarely occur in patients less than 40 years old and can present with a multitude of gastrointestinal symptoms including melena and hematochezia. We present a case of an extragastrointestinal stromal tumor (EGIST) causing abdominal pain, melena, and hematochezia in a 34-year-old Hispanic male.

Case Description/Methods: The patient presented with diffuse abdominal pain, melena, hematochezia, and severe anemia. EGD was performed without an identifiable bleeding source. Computed tomography of the abdomen revealed a large mass abutting the small bowel. The patient was taken to surgery where the mass, which was deriving from the omentum and invading the adjacent small bowel, was completely excised and found to be a spindle cell GIST. Excision margins were determined to be negative, and the patient was started on a tyrosine kinase inhibitor for maintenance therapy. The patient continues to follow-up on an outpatient basis for surveillance.

Discussion: This case represents the rare disease entity EGIST presenting outside the typical demographics of the disease in a young patient with no identified previous genetic syndromes. Gross examination of the mass in this case was also atypical given that the mass was rooted in the omentum and invading the small bowel making the primary tumor site extragastrointestinal. This case demonstrates the need to build a differential diagnosis that includes GIST, difficulty with diagnosing this disease with endoscopy alone, and the ability to successfully treat this disease if it is identified early in the clinical course.


Disclosures:


Nathan DeRon, DO¹, Huda Khan, MD². P2054 - Extragastrointestinal Stromal Tumor Arising From the Omentum Presenting as Hematochezia, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.