Table of Contents
Definition / general | Essential features | Terminology | Epidemiology | Sites | Etiology | Clinical features | Case reports | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Electron microscopy description | Sample pathology report | Differential diagnosis | Board review style question #1 | Board review style answer #1Cite this page: Gonzalez RS. Xanthoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/colonxanthoma.html. Accessed April 2nd, 2025.
Definition / general
- Localized mass forming collection of lipid bearing histiocytes
Essential features
- Rare but typically incidental and benign polypoid collection of histiocytes
Terminology
- Also called xanthomatous polyp, xanthogranulomatous inflammation, xanthelasma
Epidemiology
- Very rare in colon - stomach is most common gastrointestinal site
Sites
- Colonic examples almost always rectosigmoid
Etiology
- May be due to prior injury
Clinical features
- Colon polyp
- May clinically resemble carcinoma
- May cause intestinal obstruction if more extensive and involving deeper layers
Case reports
- 38 year old woman with xanthogranulomatous inflammation presenting as a submucosal mass of the sigmoid colon (Pathol Int 2005;55:440)
- 68 year old man with xanthoma disseminatum with large plaques confined to the back, pulmonary involvement and multiple intestinal xanthomas (Dermatology 2004;208:164)
Microscopic (histologic) description
- Collection of foamy cells without mucin, typically limited to lamina propria
- Associated with surface hyperplastic change (APMIS 2004;112:3)
Microscopic (histologic) images
Positive stains
Negative stains
- PAS-diastase, Alcian blue (pH 2.5 or 1.0), mucicarmine
Electron microscopy description
- Electron dense globules
Sample pathology report
- Descending colon, polypectomy:
- Xanthoma
Differential diagnosis
- Muciphages:
- Present in up to 40% of rectal biopsies but usually contain mucin (Am J Surg Pathol 2000;24:1009)
Board review style question #1
Board review style answer #1