Table of Contents
Definition / general | Case reports | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stainsCite this page: Hamodat M. Necrobiotic xanthogranuloma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/skinnontumornecrobioticxanthogranuloma.html. Accessed April 2nd, 2025.
Definition / general
- Head, neck and trunk lesions similar to necrobiosis lipoidica but associated with IgG paraproteinemia and not diabetes
Case reports
- 64 year old woman with multiple nodules (Dermatol Res Pract 2011;2011:927852)
Gross description
- Yellowish papules / nodules
Microscopic (histologic) description
- Marked necrobiosis alternating with foci of xanthogranulomatous infiltration through the reticular dermis with extension into subcutaneous fat
- Septal distribution may mimic panniculitis
- Granulomatous infiltrate is associated with epithelioid and foamy histiocytes in addition to conspicuous giant cells, many of Touton type; also foreign body giant cells, lymphocytes and plasma cells, cholesterol clefts
- Asteroid bodies often found in cytoplasm of giant cells
- Granulomatous and necrobiotic process may also affect muscular arteries
Microscopic (histologic) images
Positive stains
- Oil Red O may reveal focal lipid droplets
- Direct immunofluorescence shows IgM, C3 and fibrinogen deposits in blood vessel wall
- Alcian blue staining may reveal small amount of interstitial mucin
Negative stains
- No elastic fibers in necrobiotic areas