What should you know about keratin cyst scalp?

A keratin cyst on the scalp is often a firm, smooth lump that can be monitored or removed after clinical assessment. Scalp cysts may become noticeable when brushing, washing, wearing headwear, or resting the head. A hands-on examination helps distinguish a pilar cyst from other lumps.

A pilar cyst, also called a trichilemmal cyst, develops from a hair-follicle lining and contains keratin. It commonly feels round and mobile beneath the scalp, although a larger or irritated lump may be tender. Several cysts can occur in the same family. A cyst can rupture after pressure or an accidental knock, causing soreness and inflammation. A new lump should not be diagnosed from appearance alone because scalp growths have different causes.

Avoid squeezing the lump or trying to drain it with a needle. Use a gentle shampoo and take care when combing around the area. Book an assessment if it is growing, repeatedly snagged, painful, or difficult to examine. If removal is chosen, a clinician can numb the scalp, open the skin, and remove the cyst and its lining. Ask about wound care and how hair washing should be handled afterward. For background on lumps, see the Skin Lumps guide.

Seek prompt care for increasing pain, warmth, marked redness, pus, fever, or redness spreading from the lump. Arrange an earlier review if it bleeds, ulcerates, becomes fixed, changes quickly, or causes persistent headaches because of its size or position. Sudden swelling after an injury also deserves assessment. Do not assume every scalp lump is a cyst.

Ask whether the lump feels like a pilar cyst, whether monitoring is reasonable, and what signs would change that plan. If removal is discussed, ask how the procedure affects hair, where the incision will be, how long the dressing stays on, and how recurrence will be handled.