Xanthoma

A xanthoma (pl. xanthomas or xanthomata) (condition: xanthomatosis), from Greek xanthos, ξανθος, "yellow", is a deposition of yellowish cholesterol-rich material that can appear anywhere in the body in various disease states. They are cutaneous manifestations of lipidosis in which lipids accumulate in large foam cells within the skin. They are associated with hyperlipidemias, both primary and secondary types.

Tendon xanthomas are associated with type II hyperlipidemia, chronic biliary tract obstruction, and primary biliary cirrhosis. Palmar xanthomata and tuboeruptive xanthomata (over knees and elbows) occur in type III hyperlipidemia.

Types

Xanthelasma

A xanthelasma is a sharply demarcated yellowish collection of cholesterol underneath the skin, usually on or around the eyelids. Strictly, a xanthelasma is a distinct condition, only being called a xanthoma when becoming larger and nodular, assuming tumorous proportions. Still, it is often classified simply as a subtype of xanthoma.