A Pilar cyst is a type of benign growth that usually appears on the scalp. These cysts are filled with a thick, yellowish substance called keratin, which is a protein found in skin, hair, and nails. Pilar cysts are often round and smooth, and they can vary in size. They are generally harmless and do not cause any pain, but some people choose to have them removed for cosmetic reasons.
These cysts are more common in women and can run in families, suggesting a genetic link. While they can occur at any age, they are most frequently seen in adults. If a pilar cyst becomes inflamed or infected, it may require medical attention, but most cases are easily managed.