This highly elevated lesion, which clinically is called cutaneous horn may be a verruca vulgaris, seborrhoic keratosis, inverted follicular keratosis and rarely a squamous cell carcinoma or sebaceous-gland carcinoma. Excsional biopsy and histologic examination necessary for diagnosis
Naumann, G.O.H., Prof. Dr. med., Univ.-Augenklinik, Erlangen, Germany