A Colonic Polypoid Ganglioneuroma: An Unexpected Finding on a Screening Colonoscopy

Abstract

Introduction: Ganglioneuromas are benign peripheral neuroblastic tumors of the neuroectodermal family composed of mature ganglion cells, schwann cells, and supporting cells. They can occur anywhere along the sympathetic chain, most commonly in the mediastinum, retroperitoneum, and adrenal glands. They most often occur in the pediatric population in association with genetic syndromes with 60% being diagnosed before age 20, and occur most often in females. Case Description: A 56 year old African-American male with Diabetes Mellitus and chronic HCV infection underwent first average-risk screening colonoscopy. The colonoscopy was completed to the cecum with good bowel preparation. A 7 mm sessile polyp, which was not characteristically adenomatous under white light, was seen at the distal sigmoid colon. This polyp was completely excised by hot snare polypectomy. The polyp was retrieved and sent for histologic examination. Immunohistochemical stain S100 highlighted the ganglion and spindle cells, supporting the diagnosis of ganglioneuroma. This unique finding highlights an unexpected case of an asymptomatic, solitary polypoid colonic ganglioneuroma. Ganglioneuromas are most often found in constellation syndromes such as multiple endocrine neoplasia type IIB (MEN-IIB), Von Recklinghausen's disease, and Cowden Syndrome. However, for a solitary colonic ganglioneuroma to be found in an asymptomatic individual, especially in an adult male; this is an exceedingly rare presentation for a rare tumor.Figure 1Figure 2Figure 3