Isolated Ganglioneuroma of the Colon

Abstract

Purpose: Ganglioneuromas (GN) are neuroectodermal tumors consisting of ganglion cells, nerve fibers and Schwann sheath elements. When found in the gastrointestinal tract, they are of uncommon occurrence. We report a case of an isolated ganglioneuroma of the colon. Case: A 43 year old Ecuadorian female who was otherwise healthy, underwent surveillance colonoscopy that revealed a 6mm polyp at the hepatic flexure and a 4mm polyp at the sigmoid colon. Histology of the resected polyps from the hepatic flexure and sigmoid colon showed tubular adenoma and ganglioneuroma respectively. Discussion: GI ganglioneuromas are rare, benign, and well differentiated reported as 3 subtypes: (1) solitary polypoid GN, (2) ganglioneuromatous polyposis and (3) diffuse ganglioneuromatosis. Polypoid GNs are small, sessile polyps that resemble juvenile polyps, adenomas, or hyperplastic polyps. Gangioneuromatous polyposis is characterized by small multiple polyps (20-40 lesions) with mature ganglion cells in the mucosa and submucosa. Diffuse ganglioneuromatosis (GNM) have band-like enlargement of the submucosal plexus and myenteric nerve plexus caused by hyperplasia of nerve fibers and ganglion cells. There are no specific symptoms eluding toward the clinical diagnosis of ganglioneuromas of the GI tract. Isolated ganglioneuromas are usually asymptomatic. Ganglion cells are not normally found within the GI mucosa. Diagnosis can be facilitated through immunostaining; S-100 protein, neuronase specific enolase (NSE) and neurofilament protein (NFP). In our patient, stains were not performed in order to make the final diagnosis. Mature ganglion cells infiltrating the submucosa as seen in the clusters of large cells with vesicular eccentrically placed nuclei and abundant eosinophilic cytoplasm are seen in high power field (See Figure 1). In the background stroma, spindle and Schwann cells are present. There is no indication for resection in asymptomatic patients. Isolated colonic ganglioneuromas have no reported predilection toward malignancy and there is no indication for long term follow-up in this patient population.Figure