S6117 A Stuck Pillcam and a Hidden Culprit: Retained VCE Reveals Multifocal Primary Small Bowel NETs With Mesenteric Complications

Introduction: Small bowel neuroendocrine tumors (NETs) are often indolent and discovered incidentally or in the context of metastatic disease. Obscure gastrointestinal bleeding and bowel obstruction are rare initial presentations and may signify multifocal primary disease or mesenteric tumor involvement. Case Description/Methods: A 62-year-old man with metastatic hepatic NETs (segment 8 dominant lesion, 4.3 cm) on everolimus, with prior PRRT and embolization, was admitted with hematemesis, melena, and abdominal pain. Esophagogastroduodenoscopy revealed Barrett’s esophagus (C0M4) and diminutive antral erosions. Colonoscopy showed 9 < 1 cm tubulovillous adenomas. He was discharged, but returned with worsening emesis, melanotic stools, and leukocytosis. VCE was retained proximal to the ileocecal valve. Imaging noted a 4.9 × 3.2 cm subpleural/pericardial mass. He underwent diagnostic laparoscopy, exploratory laparotomy, small bowel resection, and radical resection of a mesenteric mass. Pathology revealed 2 well-differentiated grade 1 NETs (1.8 and 1.0 cm), invading subserosa with lymphovascular invasion and 2/39 positive mesenteric lymph nodes (pT3 pN1). The mesenteric mass (6.0 cm) demonstrated fat necrosis and ischemic injury. Margins were negative. Discussion: This case illustrates the diagnostic complexity of obscure gastrointestinal bleeding in patients with known NETs. Despite stable metastatic disease, the patient was found to harbor multifocal primary small bowel NETs complicated by mesenteric desmoplasia and ischemia. Surgical resection remains pivotal in management, even amid systemic therapy. VCE retention and chronic nonsteroidal anti-inflammatory drug use likely contributed to symptom escalation. High clinical suspicion and timely multidisciplinary intervention are essential.