Sebaceous cyst removal: what happens, risks and recovery

A Royal Surrey leaflet describes sebaceous cysts as benign growths beneath the skin, filled with keratin, firm and round, and commonly on the face, neck or trunk. A Lincolnshire leaflet describes cysts more broadly as round growths just under the skin that contain material or liquid. They are benign, which means not cancer.

Most do not have to come out. Removal is generally considered when a cyst is uncomfortable, repeatedly inflamed, in a place where it rubs or catches, or bothers the person cosmetically. If it is quiet and painless, leaving it is a valid choice, though it will not go away by itself.

Timing matters. The Royal Surrey leaflet says an inflamed cyst should not be removed during the acute inflammatory phase because that can increase complications, and the inflammation should be treated first. A red, hot, tender cyst is usually something to be assessed by your GP, who may treat the infection before any operation is planned.

The leaflets retrieved do not detail non-surgical options in depth, but the sensible alternatives are watchful waiting and treating flare-ups as they happen. Ask your GP before trying to squeeze or drain a cyst yourself.

If a cyst keeps getting infected or leaking, that is a strong reason to discuss planned removal with the GP. Your GP will tell you whether the NHS or a private minor surgery service is the route, as local arrangements vary.

For local anaesthetic you can normally eat and drink as usual, but follow whatever your appointment letter says. Tell the team about blood-thinning medicines, allergies and any previous reaction to local anaesthetic.

Wear clothes that give easy access to the area, and plan for the first 48 hours to be quiet, as Oxford advises taking things easily to reduce bleeding. If the cyst is on a foot or lower leg, expect to elevate the leg for a couple of days, and a cyst on the hand may need a sling for a short time.

The Royal Surrey leaflet describes a day case under local anaesthetic, with the patient awake. The skin is cleaned and numbed, a small cut is made over the cyst, and the cyst and its wall are carefully removed, aiming to keep the scar small. The wound is closed with stitches.

The key technical point is the wall. The leaflet says cysts can return if not completely removed, so the surgeon aims to take the whole sac out intact. Sometimes a lump removed as a cyst is sent to the laboratory to confirm what it is, which the Milton Keynes leaflet gives as one of the reasons for excision.

The Royal Surrey leaflet lists recurrence, infection and scarring. Milton Keynes lists pain, bleeding, bruising, infection and scarring, and notes that a small number of people have an inherited tendency to unusually red, raised scars. Numbness around the wound can occur, and swelling and bruising typically settle in one to two weeks according to Milton Keynes.

A wound that bleeds can usually be controlled by pressure, and Oxford advises firm pressure with a clean tissue or gauze for about ten minutes without checking. An infected wound may need antibiotics from the GP.

Oxford says to keep the wound dry and clean for the first 24 hours, then wash it gently with unperfumed soap and pat dry, and avoid activity that stretches the area for the first week. Stitches that do not dissolve are removed after about a week according to Milton Keynes, and Cambridge gives 7 to 14 days depending on the site.

Most people return to ordinary activity within days. Oxford says wounds stay weak for up to six weeks and the scar continues to mature for over a year, so moisturising, massage after healing and sun protection of factor 50 are suggested.

Swelling, spreading redness, increasing pain, cloudy or foul-smelling discharge, a fever or feeling unwell may mean infection. Contact your GP promptly, or NHS 111 out of hours. If the wound opens, bleeds continuously despite pressure, or you are worried, attend an emergency department.