Abstract
Benign giant-cell synovioma, the most frequent example of which is the well-known myeloid tumour of tendon sheaths, is used as a text for the discussion of the true significance of the so-called "xanthoma" cell. These cells are the result of the phagocytosis of cholesterol esters and are of varied histogenesis. Some are undoubtedly of neoplastic origin; most of them are not, being usually histiocytic, fibrocytic, serosal or endothelial. There is no such thing as a specific xanthoma cell.
The term "xanthosis" might well be used to designate this process of infiltration of tissue with cholesterol fat, and the prefix "xantho-" or the adjective "xanthic" in tumour terminology, as for example in "fibro-xantho-sarcoma," "xanthic neurofibroma," and so on.