Clinicopathological and Immunohistochemical Characteristics of Verruciform Xanthoma of the Lower Gingiva: A Case Report.

Verruciform xanthoma (VX) is a rare benign lesion and mainly effects the oral mucosa. This slow-growing asymptomatic lesion typically develops along the gingival margin of the masticatory mucosa, followed by the hard palate, tongue, buccal mucosa, floor of the mouth, alveolar mucosa, soft palate and junction between the hard and soft palate. Moreover, this lesion can also affect the skin and genital organs. Clinically, VX generally presents a sessile or pedunculated appearance, forming a papule or single plaque with verrucous or papillomatous mucosal growth. The colour (white, pink, grey, or yellow) depends on the thickness of the overlying epidermis. In fact, the clinical findings of VX are similar to those of verrucous carcinoma and other benign tumours, such as squamous papilloma, verruca vulgaris and mucosal fibroma. For this reason, clinical and histopathological examinations are essential for accurate differential diagnosis. Histologically, VX is characterized by parakeratosis, rete ridges of uniform depth and the accumulation of foam cells, which are also called "xanthoma cells". Here, we describe the clinicopathological and immunohistochemical findings of a VX located on the lower gingiva of a 64-year-old male patient.