What should you know about scalp cyst types?

A pilar cyst, also called a trichilemmal cyst, develops from a hair follicle and commonly feels like a smooth, firm, mobile lump in the scalp. Other skin cysts can contain keratin and may have a visible opening. A cyst is different from a solid growth, an abscess, or a swollen lymph node, so appearance alone cannot confirm the type. Some remain quiet for a long time; rubbing, pressure or a break in the skin can make one tender, red or swollen.

Do not squeeze, pierce or repeatedly press the lump, because this can irritate it or introduce infection. Take note of its location, approximate size, tenderness and any change in the overlying skin. A clinician can examine it and explain whether observation is reasonable. If it keeps catching on a comb, becomes uncomfortable or returns after draining, discuss cyst removal; removing the cyst wall may matter when recurrence is a concern.

Arrange a prompt assessment if the lump becomes rapidly larger, hot, very painful, increasingly red, draining or associated with fever. Seek care sooner if several lumps appear, the skin breaks down, or the diagnosis is uncertain. Urgent help is appropriate for severe swelling with difficulty opening the eyes, breathing or swallowing, although these symptoms are not typical of a simple scalp cyst.

Ask: Does this feel like a pilar cyst or another type of lump? What changes should I monitor? Would removal be useful if it is repeatedly irritated, and how would the area be cared for afterward?