Oral verruciform xanthoma: a clinicopathologic and immunohistochemical study of 20 cases.

Verruciform xanthoma of the oral cavity is an uncommon benign lesion that usually affects the palate and gingiva mainly as a well-circumscribed solitary yellowish to whitish plaque or nodule, which is promptly recognized microscopically by identification of sub-epithelial foamy macrophages. The aim of this study was to evaluate the clinicopathologic and immunohistochemical features of 20 cases of oral verruciform xanthoma. All cases were evaluated by conventional hematoxylin/eosin staining and six of those were submitted to immunohistochemical reactions for CD68, CD63, CD163, syndecan-1 (CD138), S-100 protein and cytokeratins (CK) 8, 14 and 19. Oral verruciform xanthoma presented as yellowish papillary nodules affecting mainly the palate (30%), buccal mucosa (30%) and gingiva (25%) of middle-aged male patients. Most cases presented papillary epithelial hyperplasia and sub-epithelial foamy cells, which were immunopositive for CD68, CD63 and CD163 in all cases. The orange parakeratin superficial layer was negative for CK14 and presented a distinct granular membrane pattern of positivity for CD138. S-100 protein, CK8, and CK19 were negative.