Small intestine & ampulla
Benign tumors / tumor-like conditions
Leiomyoma
Author: Hanni Gulwani, M.B.B.S.
Last author update: 1 August 2012
Last staff update: 21 July 2023
Copyright: 2003-2025, PathologyOutlines.com, Inc.
PubMed Search: Leiomyoma small bowel
Table of Contents
Definition / general | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosisCite this page: Gulwani H. Leiomyoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/smallbowelleiomyoma.html. Accessed March 29th, 2025.
Definition / general
- Benign smooth muscle tumors that arise from small bowel muscularis propria or muscular mucosa
- Duodenal leiomyomas of muscular mucosa are incidental, 1 - 2 mm, merge with muscularis mucosa; those not from muscularis mucosa are also often incidental but larger, 2 - 4 cm, with firm, white, whorled cut surface
Microscopic (histologic) description
- Low cellularity, no / rare mitotic figures, resembles esophageal leiomyoma
Microscopic (histologic) images
AFIP images
Esophageal leiomyomas
Positive stains
Differential diagnosis
- GIST: often cytologically malignant in small bowel; CD117+, often CD34+ (Rom J Morphol Embryol 2011;52:1121, Am J Surg Pathol 2003;27:625)
