Verruciform xanthoma has papillary architecture and shows acanthosis, hyperkeratosis and parakeratosis. Loose keratin squames with bright orange-pink color are present on the surface of the papillae as well as within crypts. The epidermal ridges show bulbous expansion and some appear coalesced at their bases. There is marked keratinocyte necrosis associated with a prominent neutrophilic infiltrate. The dermal component of the papillae contains an admixture of foamy or granular xanthoma cells, neutrophils, plasma cells, and lymphocytes in a background of vascular stroma. There is no epithelial atypia and viral inclusions are not present.
Verruciform xanthoma must be distinguished from condyloma, granular cell tumor, and verrucous carcinoma.