Definition:

Xanthomas are benign and usually yellow plaques, papules, or nodules that develop in the cutis and subcutaneous tissue. They evolve as clusters of foam cells and favor the neck, upper trunk, flexural folds and periorbital region. The foam cells are formed from macrophages as a consequence of gradual intracellular accumulation of lipids taken up by specific receptors or by the mechanism of phagocytosis. They are seen in several lipidoses and are usually indicative of a derangement in lipoprotein metabolism, in particular familial hypercholesterolemia. Prevention of xanthomas goes hand in hand with the management of the underlying disorders of lipid metabolism. Normolipemic xanthomatosis may be seen in several rare conditions.