Recommended Citation
Stevenson JR, Momin A, Latif SU. Obstructing Periampullary Duodenal Gangliocytic Paraganglioma Managed With En Bloc Endoscopic Mucosal Resection After Prolonged Surveillance. Poster presented at: American College of Gastroenterology (ACG) 2026 Annual Scientific Meeting; October 11, 2026; Nashville, TN. Poster P1511.
Presentation Notes
Poster presented at: American College of Gastroenterology (ACG) 2026 Annual Scientific Meeting; October 11, 2026; Nashville, TN. Poster P1511.
Abstract
Introduction: Gangliocytic paraganglioma (GP) is a rare, typically periampullary duodenal neuroendocrine neoplasm. Although often indolent, GP may cause bleeding, pain, and obstruction. Submucosal location and triphasic histology hinder preoperative diagnosis. We report a periampullary GP followed as a presumed spindle-cell lesion until melena and obstruction prompted en bloc endoscopic mucosal resection (EMR), avoiding pancreaticoduodenectomy. Case Description: In 2017, computed tomography angiography for vascular evaluation incidentally identified a 35 mm soft tissue mass in the second portion of the duodenum. Esophagogastroduodenoscopy (EGD) showed mass effect with normal mucosa. Endoscopic ultrasound (EUS) fine-needle aspiration was nondiagnostic; repeat EUS fine-needle biopsy showed a bland spindle-cell lesion. Given stability and surgical risk, multidisciplinary review favored surveillance. In early 2023, the patient presented with melena and anemia. EGD revealed a 3 cm mass with central ulceration and oozing; biopsy favored GP, with ganglioneuroma and neuroendocrine tumor in the differential. By June 2023, the lesion obstructed >75% of the lumen within 2 cm of the ampulla. Patient was not a candidate for surgery. Endoscopic submucosal dissection was attempted but abandoned for scope instability; en bloc EMR was completed with hot snare polypectomy. Post-resection bleeding was controlled with epinephrine, coagulation forceps, thermal coagulation, and clips. Specimen migration to the proximal jejunum caused luminal obstruction, requiring complex retrieval. Final pathology confirmed a 4.0 cm GP extending to inked margins. Six-month surveillance EGD showed no residual disease. Discussion: GP is typically managed conservatively given its indolent biology; bleeding or obstruction warrants intervention, as here. R1 endoscopic resection has prompted salvage pancreaticoduodenectomy in prior reports; negative six-month surveillance supported continued non-operative management. Triphasic epithelioid, spindle, and ganglion-like cells may mimic spindle-cell tumor, ganglioneuroma, or neuroendocrine tumor on limited sampling. Resection immunohistochemistry (synaptophysin, chromogranin, S- 100, pancytokeratin, GATA3) confirmed the diagnosis. GP belongs in the differential for periampullary submucosal lesions with bleeding or obstruction. AI use disclosure: Generative AI tools assisted with literature review and language editing; no patient-identifiable information was entered, and authors verified content. A B Figure 1. Endoscopic Appearance Before and After En Bloc Endoscopic Mucosal Resection of an Obstructing Periampullary Duodenal Gangliocytic Paraganglioma. (A) Pre-resection EGD demonstrating a large polypoid submucosal lesion in the second portion of the duodenum with marked luminal obstruction. (B) Post-resection EGD after en bloc endoscopic mucosal resection with adequate hemostasis achieved. A B Figure 2. Cross-Sectional and Endosonographic Features of a Periampullary Duodenal Gangliocytic Paraganglioma. (A) Contrast-enhanced computed tomography of the abdomen demonstrating a well-circumscribed soft tissue mass in the second portion of the duodenum near the ampulla (red circle). (B) Endoscopic ultrasound demonstrating a hypoechoic periampullary submucosal lesion.
Type
Poster
Affiliations
Aurora Health Care