Verruciform xanthoma associated with lichen planus

Abstract

Verruciform xanthoma (VX) is a rare benign lesion of unknown etiology, with a rough or papillary aspect, painless, sessile, well-defined, most lesions do not exceed 2 cm in their largest diameter, the degree of keratinization of the surface influences color, varying white to red, affecting mainly the gingiva and alveolar mucosa, and can also be seen in skin and genital. Herein, we present a report a clinical case of oral verruciform xanthoma in the buccal mucosa associated with the lichen planus lesion, as well as the morphological and immunohistochemical characteristics of the lesion. The clinical diagnostic hypothesis of oral lichen planus of the white reticular lesions on the buccal mucosa and on the tongue was confirmed by histopathology before a subepithelial connective tissue exhibiting intense inflammatory infiltrate in a predominantly lymphocytic band. In contrast, the hypothesis of the verrucous lesion in the left buccal mucosa was leukoplakia, with histopathological evidence showing exophytic and digitiform proliferations with parakeratin plugs between the papillary projections. Subepithelial connective tissue was characterized by macrophages with foamy cytoplasm (xanthoma cells). An immunohistochemical examination was performed, showing positivity for CD68, a macrophage marker, in addition to testing by Schiff's periodic acid (PAS) with diastasis, which was detected the presence of lipids inside these macrophages. The patient is free of recurrences of verruciform xanthoma and is being monitored due to the presence of lesions of oral lichen planus.

Keywords: Foam cells; Mouth Mucosa; Pathology.

Figure 1. Clinical aspect of lesions clinically diagnosed as OLP and leukoplakia. A – white reticular lesions on the right buccal mucosa; B – white warty lesion on the left buccal mucosa adjacent to reticular lesions; C and D – white lesions on the right and left lateral borders of the tongue.

Figure 2. Microscopic characteristics of the OLP, lesion removed from the right buccal mucosa: A – lesion covered by stratified hyperortokeratinized squamous epithelium displaying a banded subepithelial inflammatory infiltrate (H&E, scale bar 50 µm; B – epithelial changes comprising exocytosis and spongiosis and predominantly lymphocytic connective tissue inflammatory infiltrate )H&E, scale bar 200 µm).

Figure 3. Microscopic characteristics of the VX, lesion removed from the left buccal mucosa: A – digitiform proliferation of the stratified parakeratinized squamous epithelium (H&E scale bar 200 µm; B – presence of spongy or xanthoma cells ( H&E; scale bar 100 µm); C and D – positive CD68 immunoexpression in spongy cells (C scale bar 200 µm; D scale bar 50 µm).

Figure 4. Microscopic characteristics of the VX, lesion removed from the left buccal mucosa: A and B – positivity for PAS with diastasis. (A scale bar 200 µm; B scale bar 50 µm).