[ Pilar sheath acanthoma - a benign follicular hamartoma].

A new case of pilar sheath acanthoma is reported. This tumor has been identified in 1978 and shows characteristic histological features: a central sinus with keratinous material, a pore-like opening to the surface, keratinization of the epidermoid type and projecting epithelial tumor lobes containing small keratin cysts resembling incomplete pilar differentiation.