Verruciform xanthoma: an immunocytochemical study.

Verruciform xanthoma is a rare lesion that occurs predominantly on the oral mucosae, but also on other mucosal sites and on the skin. We report an immunocytochemical analysis of the xanthoma cells in three cases of verruciform xanthoma (two vulval and one scrotal), and also attempt to identify human papilloma virus (HPV) as a possible trigger for the production of these lesions. We employed a panel of seven histiocytic markers (CD68 [KP1], KiM1P, HAM 56, lysozyme, vimentin, peanut agglutinin and factor X111a) and two others to identify HPV involvement (CAMVIR-1 and bovine papilloma virus-1 [BPV-1]). Results showed the xanthoma cells to be positive for CD68, KiM1P, HAM 56 and vimentin, with less consistent labelling for peanut agglutinin and lysozyme. CAMVIR-1 and BPV-1 were negative in all three cases. These findings support the view that the xanthoma cells are derived from a monocyte macrophage lineage and fail to demonstrate HPV as the cause.