Bitaal Sadiq, BS1, Matthew Nunez, BS1, Shilpa Sannapaneni, MD2, Amanda Hoelscher, PA-C3, Donna J. Lager, MD3, Rajeev Jain, MD3, Chris Fourment, MD1, Timothy E. Ritter, MD1
1Texas Digestive Disease Consultants, PA, Southlake, TX; 2Texas Health Presbyterian, Dallas, TX; 3Texas Digestive Disease Consultants, PA, Dallas, TX
Introduction: Mucosal Schwann cell hamartoma (MSCH) is a benign mucosal lesion composed of spindle cells surrounding colonic crypts that can arise anywhere in the colon; usually in the rectosigmoid. Most reports of colonic MSCH are limited to case reports and two case series from tertiary-care academic settings involving 20 and 26 patients. Our retrospective study is the first to describe the characteristics of colorectal MSCH in a community gastroenterology practice.
Methods: We retrospectively identified patients with colorectal MSCH from the pathology database of a large, community gastroenterology practice of 157 physicians in Texas and Louisiana working at 24 outpatient centers. Data were collected from consecutive patients diagnosed with MSCH from 2015-2019. MSCH were confirmed by positive immunohistochemical staining for S-100. Historical data recorded included the endoscopic size and appearance of the polyps, location, indication(s) for colonoscopy, and patient age, sex, and race.
Results: 184 colorectal MSCH from 179 patients were identified out of a total of 335,635 colon specimens. The median age of 59 years (range, 40-84). Sixty percent were female, 67% were White, and 25% were Black. The most common indications for colonoscopy were screening (55%), polyp surveillance (35%) and diagnostic (35%), which often overlapped. The polyps were described as sessile (65%), pedunculated (2%), mixed sessile/pedunculated (1.6%), and not specified (32%). The average size was 3.8 mm (range, 1-15 mm), and most were in the distal colon and rectum (77%) followed by transverse (11%) and proximal colon (10%). One MSCH was at an anastomosis and in one, the site was not specified.
Discussion: This large retrospective series is the first to describe colorectal MSCH in a community gastroenterology practice. Additionally, the large number of patients provides a better description of MSCH characteristics in comparison to prior small case series. MSCH were most commonly found during screening and surveillance colonoscopies in patients who were older, female and white. Most were located in the distal colon and rectum. Colorectal MSCHs are found infrequently at an approximate rate of 1 every 4 years by a community gastroenterologist, or 0.05% of colonoscopy biopsies.
Citation: Bitaal Sadiq, BS; Matthew Nunez, BS; Shilpa Sannapaneni, MD; Amanda Hoelscher, PA-C; Donna J. Lager, MD; Rajeev Jain, MD; Chris Fourment, MD; Timothy E. Ritter, MD. P0126 - COLORECTAL MUCOSAL SCHWANN CELL HAMARTOMAS IN A COMMUNITY GASTROENTEROLOGY PRACTICE. Program No. P0126. ACG 2019 Annual Scientific Meeting Abstracts. San Antonio, Texas: American College of Gastroenterology.