Abstract
A 46-year-old man had a brown verrucous lesion on his neck since his birth. He noticed three tumors on the lesion in the previous two months. Since these tumors rapidly increased in size, he visited our department. On examination, a rice-grain sized hyperkeratotic pediclated nodule, a pea sized cutaneous horn and a rice-grain sized dark nodule were all observed on a brown verrucous plaque. The plaque was totally resected surgically. Histopathologically, the three kinds of tumors were diagnosed as isolated epidermolytic acanthoma, trichilemmal horn, and seborrheic keratosis, respectively, which had all developed on an organoid nevus. We reviewed a total of 241 cases of organoid nevi in our department over the past 22 years, and also discuss the statistics of secondary tumors associated with organoid nevi.
