P2317 - Numerous Colonic Ganglioneuromas: A Rare Finding During Routine Colonoscopy

Shelby McNeilly, MS¹, Christine Granato, MD^2
1Philadelphia College of Osteopathic Medicine, Philadelphia, PA; ²Associated Gastroenterologists of Central New York, Camillus, NY

Introduction: Ganglioneuromas (GNs) arise from sympathetic ganglion cells, specifically embryonic neural crest cells. They are typically asymptomatic, occur at any anatomic location, however, most GNs are found in the head, neck and/or adrenal glands1. We present a case of a 50-year-old male with 18 polyps found on routine colonoscopy, nine of which were incidental GNs confirmed by histopathology.

Case Description/Methods: A 50-year-old average-risk Caucasian male was referred for a positive multitarget stool DNA test. Colonoscopy was notable for 18 subcentimeter polyps, all of which were removed by cold or hot snare polypectomy. Nine of the 18 polyps were GNs, the remainder were adenomas. Endoscopically, the GNs were grossly indistinguishable from traditional adenomas (see images a and b). The patient was referred for genetic consultation to rule out Cowden Syndrome, MEN-2 and NF-1.

Discussion: GNs are rare neuroblastic tumors that are characterized as benign overgrowths of mature ganglion, satellite and Schwann cells with a fibrous stroma1. They are classically found in the posterior mediastinum (41.5%), retroperitoneum (37.5%), adrenal glands (21%) and neck (8%)1. Histopathology confirms their diagnosis with hematoxylin and eosin staining and characteristic S100, SOX-10 and synaptophysin staining1.

GNs in the colon can signify a polyposis syndrome. These are categorized based on degree of GN formation; most commonly, polypoid ganglioneuroma, ganglioneuromatous polyposis or diffuse ganglioneuromatosis2. Polypoid ganglioneuromas are nests of ganglion cells in the intestinal mucosa, few in number and resemble hyperplastic polyps or adenomas2. Ganglioneuromatous polyposis commonly presents with greater than 20 sessile or pedunculated mucosal and/or submucosal lesions without destruction of surrounding tissues2. In diffuse ganglioneuromatosis, ganglioneuromas are large (1-17 cm), disseminated, distort surrounding tissues and have an association with neuroendocrine familial syndromes, such as MEN2b, NF-1 and Cowden Syndrome2.

Colonic GNs are a rare finding during routine colonoscopy. The discovery of multiple GNs may indicate an underlying polyposis syndrome which may warrant genetic consultation for other neuroendocrine familial syndromes.

1. Shaheen, AA et al. Pancreatic Ganglioneuroma Presenting in an Octogenarian. 2021;8(3):e00546.


2. Chan, O, Haghighi, P. Hamartomatous Polyps of the Colon. 2006;130(10)1561-1566.

Disclosures:


Shelby McNeilly, MS¹, Christine Granato, MD². P2317 - Numerous Colonic Ganglioneuromas: A Rare Finding During Routine Colonoscopy, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.