Jan 19 2009
Nevus Sebaceus
Nevus sebaceus is a hairless area that is present at birth. It usually occurs on the scalp and less commonly on the neck or trunk. The surface may be smooth or pebbly and the color is often yellow to yellow-orange.
Nevus sebaceus represents a localized abnormality with too many sebaceus glands and few, malformed hairs. This type of birthmark is not inherited and may occur equally in males and females of all races. Nevus sebaceus enlarges as a child grows. Occasionally, it is more obvious at birth because hormones from a mother cause sebaceus glands in the lesion to be active. As the baby ages, it may become less apparent as hormone levels decrease. Likewise, as the child enters puberty, the lesion becomes more raised, thickened and nodular.
Because 10% - 15% of nevus sebaceus may become cancerous during adolescence or as an adult, local excision is advised before the teenage years. Preadolescence (7-11 yrs) is often an appropriate time for lesions that are not of cosmetic concern. Lesions, which pose a cosmetic issue, can be removed earlier under general anesthesia.
