S1663 The Nerves of the Colon

Abstract

INTRODUCTION: Ganglioneuromas are benign, rare and slow growing tumors that typically begin growth within sympathetic ganglion cells. Uncommonly, ganglioneuromas can initiate growth within the colon. Our case report details a 72 year-old male presenting with unexplained chronic diarrhea that resulted in an extensive non-invasive work-up, followed by colonoscopy revealing the ultimate diagnosis of colonic ganglioneuroma. CASE DESCRIPTION/METHODS: 72 year-old male with a past medical history of hypertension and hypothyroidism presented to the clinic with complaints of chronic diarrhea. The patient reported years of chronic non-bloody loose stools, 3-4 times per day with associated urgency and lower abdominal cramps. Symptoms were relieved after defecation. The patient had attempted loperamide, probiotics and multiple dietary modifications without improvement. Last colonoscopy for colorectal screening was three years prior yielding grade II internal hemorrhoids and one single tubular adenoma. On presentation, the patient was afebrile with normal vital signs and benign physical exam. He underwent an extensive workup for chronic diarrhea including complete blood count and metabolic panel, ESR, CRP, TSH, stool C. diff toxin gene PCR, ova and parasite, giardia and cryptosporidium antibodies, celiac panel, lactoferrin, ANCA, proteinase3 antibody, myeloperoxidase antibody, fecal fat and HIV screening; all within normal limits. The patient subsequently underwent colonoscopy with findings of a 20 mm flat polyp in the ascending colon with histology findings of positive S-100 immunostain; negative for CD117 and CD34 immunostain, consistent with ganglioneuroma. DISCUSSION: Ganglioneuromas most commonly arise within the head and neck area or adrenal glands and are rarely found within the gastrointestinal (GI) tract. When in the GI tract, ganglioneuromas may present in three forms: isolated polyp (polypoid), multiple polyps (ganglioneuromatous polyposis) or diffuse polyps of the bowel wall (intestinal ganglioneuromatosis). Current treatment for solitary ganglioneuromatous polyps is resection, which is curative and offers a favorable prognosis; with almost no change in clinical mortality. No current guidelines exist for surveillance of recurrence. For cases with multiple polyps or diffuse bowel wall involvement, genetic screening may be indicated to screen for associated syndromes, such as neurofibromatosis 1, MEN 2B, NFAP or Cowden’s disease.Figure 1.: A 15 mm polypoid lesion was found in the proximal descending colon. The lesion was sessile. No bleeding was present. This was biopsied with a cold forceps for histology.Figure 2.: Hematoxylin an eosin staining showed spindle-cell proliferation in submucosa that shows S100 immunoreactivity.Figure 3.: A few ganglion cell shows synaptophysin immunoreactivity.