Quick answer: A skin cyst often called a sebaceous cyst may be an epidermoid or pilar cyst. Not every cyst needs removal. A large, painful or repeatedly inflamed lump should be assessed; do not squeeze it. Excision may be considered once the diagnosis and any infection are addressed. See skin-lump assessment and minor procedures NHS skin cyst guidance.
What they are
Slow-growing benign cysts containing keratin. Common on the scalp, face, back and trunk.
When to remove
Pain, interference with daily activities, recurrent inflammation, increasing size or uncertainty about the diagnosis. An unexplained lump should be assessed before deciding on removal.
The procedure
Local anaesthesia, elliptical incision, complete excision of the cyst wall (essential to prevent recurrence), closure with dissolvable sutures.
Recovery
Resume normal activity immediately. Avoid swimming for 2 weeks.
Histology
The specimen is sent for histology — almost always confirms benign disease.