A verrucous plaque on the intergluteal cleft

Physical examination showed a brownish-pink, verruciform plaque with a raised, hyperkeratotic border, 2 cm in diameter, located in the upper region of the gluteal cleft [Figure 1]. Histological study of the lesion revealed moderate hyperkeratosis associated with verruciform epidermal hyperplasia with significant elongation of the crests [Figure 2], as well as a column of parakeratosis, the lower vertex of which was situated on a reduced granular layer and dyskeratotic, vacuolated keratinocytes. Clinically, it starts as small hyperkeratotic papules with a tendency to join and extend symmetrically on both buttocks, forming a pink verrucous plaque in the shape of butterfly wings with peripheral satellite lesions, accompanied by intense pruritus.