nevus sebaceus of Jadassohn, a congenital skin neoplasm with several cutaneous tissue elements. The most common location is the scalp, face, or neck. It may appear as a yellow or tan waxy patch of alopecia at birth. During puberty the lesion becomes raised, thick, and verrucous. It is usually treated with local excision. Untreated, the lesion may remain benign or become a malignant growth in later life. Also called nevus sebaceus.
