Exclusive facial porokeratosis: histopathologically showing follicular cornoid lamellae.

Porokeratosis is a heterogeneous group of disorders that are mostly inherited in an autosomal dominant fashion. It has a wide variety of clinical manifestations with a characteristic histological finding of cornoid lamella. Porokeratosis usually affects the trunk or the extremities. Exclusive facial lesions are rare, although 15% of patients with disseminated, superficial, actinic porokeratosis do have facial lesions. Herein, we discuss the case of a 25-year-old woman who noticed the appearance of well-defined, brownish, macular lesions located on both cheeks. She had no other symptoms. A skin examination showed well-demarcated, multiple, brownish macules with raised hyperkeratotic borders on both cheeks and a half-palm-sized, arcuate-shaped lesion formed by grouped macules on the right cheek. No other parts of the body were affected. Histopathological examination of a biopsy specimen obtained from the hyperkeratotic margin gave a diagnosis of porokeratosis with follicular involvement of the cornoid lamellae. Topical pimecrolimus was applied twice a day to the lesions, although little improvement was achieved after 2 months.