What is Nevus Sebaceous?
Nevus Sebaceous is a congenital malformation of sebaceous differentiation occurring on the scalp and sometimes the face. This results in a characteristic orange, hairless elevated, plaque with a pebbly or warty appearing surface. In about 10% of patients the Nevus Sebaceous will develop into basal cell carcinoma. Due to this fact, and for cosmetic reasons, excision is recommended at or around the time of puberty.

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Image obtained from: http://dermis.multimedica.de/bilder/CD097/550px/img0074.jpg
Wolff K, Johnson, RA. Fitzpatrick’s Color Atlas and Synopsis of Clinical Dermatology. Sixth Edition. 2009.