Nevus sebaceus

Nevus sebaceus or sebaceous nevus is a congenital, hairless plaque that typically occurs on the face or scalp. Such nevi are classified as epidermal nevi and can be present at birth, or early childhood, and affect males and females of all races equally. The condition is named for an overgrowth of sebaceous glands, a relatively uncommon hamartoma, in the area of the nevus. NSJ is first described by Josef Jadassohn in 1895.

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