Stomach
Other tumors
Schwannoma
Author: Elliot Weisenberg, M.D.
Last author update: 1 July 2012
Last staff update: 9 March 2023
Copyright: 2003-2024, PathologyOutlines.com, Inc.
PubMed Search: gastric schwannoma
Table of Contents
Definition / general | Case reports | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Board review style question #1 | Board review style answer #1Cite this page: Weisenberg E. Schwannoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/stomachschwannoma.html. Accessed November 29th, 2024.
Definition / general
- Well circumscribed, benign nerve sheath tumor (also called neurilemmoma), much less common (~ 1 / 50) in stomach than GIST
Case reports
Microscopic (histologic) description
- Well circumscribed but not encapsulated, with interlacing bundles of spindle cells and collagen
- Often nuclear pallisading, Verocay bodies, hyalinized vessels
- May have nuclear atypia, inflammatory cells, peripheral cuff of lymphoid aggregates
- No mitotic figures, no skenoid fibers, no epithelioid features
Microscopic (histologic) images
Contributed by @RaulSGonzalezMD on Twitter and Cases #455 and #347
Schwannoma
Microcystic variant of schwannoma in stomach
S100, microcystic variant
CD117, microcystic variant
46 year old woman
Positive stains
- S100 (strong), vimentin
- Often PAS+ needle shaped crystalloids (Am J Surg Pathol 1999;23:431); variable GFAP
Board review style question #1
Which of the following describes the majority of schwannomas arising in the gastrointestinal tract?
- Both encapsulated and circumscribed
- Circumscribed but not encapsulated
- Encapsulated but not circumscribed
- Neither encapsulated nor circumscribed
Board review style answer #1
