Colon tumor
Mesenchymal tumors
Mucosal Schwann cell hamartoma

Author: Raul Gonzalez, M.D. (see Authors page)

Revised: 4 January 2017, last major update June 2016

Copyright: (c) 2002-2017,, Inc.

PubMed Search: Mucosal Schwann cell hamartoma

Cite this page: Mucosal Schwann cell hamartoma. website. Accessed May 22nd, 2018.
Definition / general
  • Benign mucosal proliferation composed of Schwann cells
Essential features
  • Benign, incidental spindle cell lesion
  • Not associated with any clinical syndrome
  • Positive for S100, negative for EMA
  • Has been called "neuroma" or "neurofibroma" in past
  • Can arise anywhere in the colorectum, but more common distally
Clinical features
  • Average patient age is 62 years, with a female predominance (Am J Surg Pathol 2009;33:781)
  • Not associated with any particular syndrome
  • Lesions do not recur
  • Discovered incidentally during colonoscopy
Case reports
Clinical images

Images hosted on other servers:

Rectal polyps on colonoscopy

Gross description
  • Small (6 mm or less) sessile polyp
Microscopic (histologic) description
  • Poorly circumscribed mucosal proliferation of spindle cells, with no whorling, no palisading, no fasciculation
  • Nuclei are generally small, bland and elongated
Microscopic (histologic) images

Images hosted on PathOut servers:

Courtesy of Raul Gonzalez, M.D.

Images hosted on other servers:

Low power view on H&E

S100 positivity

Two rectal lesions (H&E and S100)

Positive stains
Differential diagnosis