The Significance of Extracellular Cholesterol Crystals or a Cholesterol Granuloma in Xanthelasma.

BACKGROUND/AIMS: Xanthelasma is an unreliable indicator of systemic hyperlipidemia. A review in search of unusual histopathologic features of cellular composition that might correlate with systemic hyperlipidemia was conducted.

METHODS

An observational case series of 3 cases was performed. Slides were stained and analyzed with hematoxylin and eosin, Masson trichrome, and periodic acid-Schiff as well as for iron. Three lesions displayed an atypical morphologic finding and were subjected to immunohistochemical analysis for CD3, CD20, CD68, CD163, S100, and adipophilin.

RESULTS

The three lesions comprised in this study had classical xanthoma cells with densely packed fine vacuoles. The xanthoma cells were CD68, CD163, and adipophilin positive and S100 negative. In case 1, extracellular, nonpolarizing cholesterol crystalloids displayed totally negative staining for all biomarkers. In cases 2 and 3, the cholesterol granulomas were surrounded and permeated by CD68- or CD163-positive epithelioid and giant cells and by CD3-positive T lymphocytes. The 3 cases each harbored squamous cysts.

CONCLUSION

In case 1, the uninflamed extracellular cholesterol crystalloids were associated with severely dysregulated systemic hyperlipidemia. In cases 2 and 3, the cholesterol granulomas were interpreted as a local manifestation of a cyst that might have partially ruptured and did not portend serious hyperlipidemia.