Nevus Sebaceous is a birthmark commonly found on the scalp, less commonly on the face, that is made of extra oil glands. It is a congenital defect that occurs before birth within the outer layer of the embryo, also known as the ectoderm. It is usually a pink or orange-colored patch on the scalp in which no hair grows.
You do not see changes in this birthmark until you hit puberty. It will then start to rise and become bumpier, which can cause discomfort in a variety of everyday tasks such as brushing, washing, or blow-drying the hair. You might feel it is slightly itchy. This is because it has developed a thicker surface and may even develop sores. If you were to itch these sores, there is a good chance the lesion will begin to bleed. Even with this abnormal discomfort, it is still safe to just be monitored over time by your doctor.
Can it be removed?
The removal of the birthmark is an option if you or your child typically desires it or are in a place where it isn’t as bearable as it once was. Many times, people may be insecure to wear their hair a certain way due to the birthmark beause of insecurity and low self-esteem. Before you get the lesion removed, however, you may need to go to a plastic surgeon for a consult, depending on how much of the scalp the lesion is covering.
Nevus Sebaceous is typically removed due to the 5-8% of lesions that develop basal cell carcinoma.  Basal Cell Carcinoma is the most common skin cancer caused by exposure to sunlight. It mainly affects the basal layer of the skin and its cells.
Is it hereditary?
No, it is most commonly a defect that occurs with no family history and simply by chance. It occurs after fertilization. Nevus Sebaceous only occurs in 0.3% of newborns, making it quite rare. If you have Nevus Sebaceous and are worried that your child might develop the lesion as well, there isn’t much to worry about. It is unlikely it can be passed on from you to a child. If your child were to develop Nevus Sebaceous, it would be by chance, not inherited.
If you are looking to get your lesion removed, consult your doctor. He or she may provide you with prescribed creams before determining whether it is a good fit to get it surgically removed, or he may provide them up until you get it removed. Nevus Sebaceous is a birth defect that commonly grows as your child does, and if any abnormal changes occur, your doctor should be notified immediately. However, it is very rare that any abnormal occurrences will take place. Your child might want the lesion removed due to the insecurity of it being exposed in public. Though, the lesion hardly causes any pain and is usually monitored up until after puberty.