Verruciform xanthoma. Further light and electron microscopic studies, with the addition of a third case.

The authors report their third case of verruciform xanthoma confirmed by electron microscopy and frozen-section lipid stains. Studies of the blood in this case revealed normal levels of triglycerides, cholesterol, and glucose, just as in the previous two cases reported. An ultrastructural search for etiologic factors with the use of material from all three cases resulted in the hypothesis that this lesion is initiated within the epithelium. The authors propose that epithelial entrapment with degeneration and accumulation of lipid may be the logical sequence of early events leading to the formation of foam cells.