Clinico-immunohistochemical Study of Oral Verruciform Xanthomas

Abstract Objective : To elucidate the immunohistochemical characteristics of oral verruciform xanthomas and the aetiology of foam cells. Patients and Methods : Oral verruciform xanthomas surgically extirpated from 5 patients were examined using immunohistochemistry. Results : The verruciform xanthomas revealed an accumulation of foam cells with clear cytoplasm in the connective tissue around the elongated epithelial rete pegs. The foam cells were intensely positive for CD-68, lysozyme, and vimentin, and were weakly positive for α-1-antitrypsin, but were negative for total keratin and S-100 protein. A small number of dendritic cells were found among the foam cells and were positive for S-100 protein. Conclusions : The findings suggest that the foam cells in oral verruciform xanthomas are of monocytemacrophage lineage and are associated with a local inflammatory immune mechanism similar to verruciform xanthomas of other organs.