Verrucous porokeratosis: A case report

Porokeratoses are uncommon hereditary or acquired keratinization disorders due to abnormal clones of keratinocytes in the epidermis. Porokeratoses have several clinical features which may occur simultaneously. A rare type is verrucous porokeratosis (VPK). Herein, we present a 47-year-old man with a 4-year history of perianal verrucous lesions and one year history of annular pruritic lesions on his extremities. Tissue biopsies from the annular and verrucous lesions showed cornoid lamellation in the horny layer with epidermal invagination and lichenoid reaction in the dermis that favored porokeratosis (PK). Genotyping for human papilloma virus (HPV) on the paraffin block of the verrucous lesion was negative. Shave excision was performed with moderate improvement. Annular and VPK lesions might coexist in an individual patient and we should consider VPK in the differential diagnoses of perianal warty lesions.