Mina Saeed, MD, Joaquin J Estrada, MD, FASCRS. Advocate Illinois Masonic MedicalCenter
Schwannomas are tumors arising from Schwann cells in the peripheral nervous system. Their presence in the gastrointestinal system is rare. Colonic schwannomas are an extremely rare variant accounting for less than 6% of mesenchymal tumors of the colon and less than 1% of all subepithelial lesions. It is estimated that fewer than a hundred cases of colonic schwannoma have been reported in the medical literature. Schwannomas of the gastrointestinal tract arise from the submucosa or the muscular propria where peripheral nerve sheaths of Auerbach's or Meissner's nerve plexuses exist. Although generally thought of as benign process, very few case reports describe local recurrence after resection and/or malignant degeneration. They pose a diagnostic challenge to the pathologist, radiologist and surgeons. Colonic schwannomas can mimic other malignancies (i.e. Gastro-Intestinal Stromal Tumors and Gastrointestinal Autonomic Nerve Tumors), which also arise from Schwann cells in the enteric nerve plexus. Therefore, immunohistochemical staining techniques are essential in diagnosing gastrointestinal schwannomas. Colonic schwannomas show diffusely strong positivity for S-100 and vimentin. They are typically negative for CD34, CD117, desmin, c-Kit and actin. Their submucosal location also poses a diagnostic dilemma endoscopically. A colonic schwannoma’s appearance is frequently inconsistent but may appear well-circumscribed, sessile, and nodular with occasional ulceration. Due to their location in the muscular propria, it is difficult to obtain an adequate tissue sample endoscopically. Accurate diagnosis is imperative as the prognosis is vastly different for other tumors included in the differential diagnosis. This paper presents the case of a 56 year-old female who underwent a laparoscopic colon resection for definitive management of a colonic schwannoma exhibiting degenerative features and servers as a comprehensive literature review of this rare colonic tumor.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 78962
Program Number: P142
Presentation Session: Poster (Non CME)
Presentation Type: Poster