The polypoid ganglioneuroma associated with hyperplastic polyposis

Ganglioneuroma (GN) of the gastroin-testinal (GI) tract is rare tumor composed of ganglion cells, nerve fibers, and supporting cells of the enteric nervous system. Diffuse ganglioneuromatosis is associated with multiple endocrine neoplasia IIB (MEN IIB), neurofibro-matosis type I (NF1, also known as von Recklinghausen disease), multiple cu-taneous or GI tract neurofibromatosis, and neurogenic sarcoma of the GI tract [1]. However, usual presentation of GN is small mucosal polyp < 1 to 2 cm, or sometimes multiple polyps. Few cases of solitary polypoid GN were reported in the literature, and colonic mucosal GN associated with colonic polyps is a very unusual finding. We report here a case of polypoid GN associated with hyperplastic polyposis and discuss the important pathological features and clinical issues. A 51-year-old Korean woman underwent colonoscopy for health checkup. The patient denied abdominal pain, diarrhea, or weight loss. She and her family had no history of familial ade-nomatous polyposis, MEN IIB, NF1, juvenile polyposis, or Cowden syndrome. During colonoscopy, numerous small sessile polyps were observed in the transverse colon, sigmoid colon, and rectum (Fig. 1A). The polyps were mainly located in rectosigmoid area. The colonoscpic biopsy was performed in polyps in size from 2 to 5 mm. Patho-logic examination of 3 polyps in cecum, 1 polyp in ascending colon, 1 polyp in hepatic fracture, 2 polyps in sigmoid colon revealed hyperplastic polyps. Pedunculated polyp in sigmoid colon showed irregular lobulation with redness , measuring 3.0 × 1.5 cm in greatest dimensions (Fig. 1B). The endoscopic finding suggested differential diagnosis for hamartomatous polyp. The pol-ypectomy was done after injection of normal saline and indigo carmine solution into the submucosal layer. The pol-yp was removed clearly by endoscopic mucosal resection. Microscopically, at low magnification the polyp showed disturbed crypt architecture with cystic glands, expanded lamina propria, and a smooth surface epithelium. Nerve gan-glion and stromal cells were also noted in the lamina propira (Fig. 2A). Under closer inspection at higher magnification , collection of spindle cells in fibril-lar matrix and irregular groups and nest of ganglion cells were observed specifically within the lamina propria (Fig. 2B). Immunohistochemically, the ganglion cells were positive for neu-ron specific enolase (NSE) (Fig. 2C) and S-100 protein (Fig. 2D). As a result of the colonoscopy, the patient also underwent esophagogastroduodenoscopy. Inner cavity of the stomach was covered with numerous sessile polyps were identified and biopsied (Fig. 1C). Patho