To the Editor.—
Polano et al reported in the October 1969 Archives that "xanthoma tuberosum occurred with equal frequency in the three groups," ie, type II, III, and IV, and suggest that "the old concept that xanthoma tuberosum and essential hypercholesterolemia belong together should be discarded."1I strongly object to this conclusion for it destroys the specificity of the type of xanthoma in relationship to the type of primary hyperlipemia. My disapprobation is twofold.
Presently there is no evidence to discredit the "eruptive xanthoma as the sole manifestation of an elevated triglyceride fraction,"2 and it being "characteristic of hyper pre-β-lipoproteinemia."3 In fact, clinical analysis of the eruptive xanthoma shows it to contain "more free fatty acids and less cholesterol esters than the tuberous and tendinous xanthomata."4 It would thus follow that the other forms of xanthoma, eg, the tuberous, are associated with hypercholesterolemia.
Prior to 1968, to