Epidermal panfolliculoma: an adnexal proliferation with advanced follicular differentiation confined to the epidermis.

Follicular differentiation can be exhibited by a variety of epidermal lesions. We report an example of panfolliculoma purely confined to the epidermis. The lesion presented as a verrucous plaque on the leg of a 55-year-old man. Histopathologic sections showed an acanthoma with follicular differentiation including areas mimicking the follicular germ, matrix, root sheath and infundibular components.