Skin Lumps and Cysts: Common Types and the Lumps Worth Having Examined

What it involves

MedlinePlus defines skin lumps as any abnormal bumps or swellings on or under the skin. It says most are benign and harmless, especially the soft kind that roll easily under the fingers, such as lipomas and cysts, but that an unexplained lump or swelling is a reason to contact a provider.

Who this is for

• Patients with a new lump or bump under the skin that has not gone away
• Patients with a known cyst that has become red, tender or painful
• Patients with a painful, red bump that may be a boil or an abscess
• Patients with a mole or spot that bleeds easily, changes shape or does not heal

What to expect

• Questions about where the lump is, when you noticed it, whether it hurts, drains or is growing, and if there are others
• An exam of the lump and the surrounding skin, since a provider can often diagnose a lump by looking and feeling
• Treatment of an infected lump, including drainage of an abscess, which the practice lists among its procedures
• Referral for a biopsy, imaging or a dermatologist if the lump needs more than an exam

The usual suspects

MedlinePlus lists lipomas, which are fatty lumps under the skin, and cysts, which are closed sacs in or under the skin filled with fluid or semisolid material. It also lists enlarged lymph glands, usually in the armpits, neck and groin; benign growths such as skin tags and seborrheic keratoses; boils, which are painful red bumps usually involving an infected hair follicle; corns, calluses, warts and moles; and abscesses, which are pus trapped in a closed space. Skin cancer is also on the list, which is why new lumps get examined.

Epidermoid cysts, up close

MedlinePlus says epidermoid cysts are very common, that their cause is unknown, and that they form when elements of the surface skin get under the skin and fill the cyst with dead skin cells. The main symptom is usually a small, painless lump beneath the skin, most often on the face, neck or trunk, often with a tiny pit in the center. It adds that these are sometimes wrongly called sebaceous cysts. They usually grow slowly and tend to stop growing at a certain size.

When a lump becomes infected

A cyst that turns red, tender or warm, or that drains grayish-white, cheesy, foul-smelling material, has become inflamed or infected, according to MedlinePlus. It says epidermoid cysts are not dangerous and do not need treatment unless they cause symptoms, and that a warm moist compress may help one drain and heal. An inflamed cyst may be injected with steroid medicine, a swollen or tender one may be drained or removed, and an infected one may need antibiotics. The practice lists incision and abscess drainage among its services.

Lumps that act differently

MedlinePlus says a painful lump or swelling that appears suddenly, over 24 to 48 hours, is usually caused by an injury or an infection. Swollen lymph glands behave differently from cysts, and the swollen lymph nodes guide explains what their pattern means. A colored or pigmented spot that bleeds easily, changes in size or shape, or crusts and does not heal is on the list of possible skin cancer, and should not be treated at home. The warts guide covers that common type of bump.

Why not treat it yourself

MedlinePlus advises that most lumps should be looked at by a provider before you try any home treatment, and says lumps from an injury can be treated with rest, ice, compression and elevation. Squeezing, cutting or draining a lump yourself risks infection and scarring. If an infected area is spreading, red streaks appear, or you have a fever, do not wait. The skin conditions guide covers when a skin change should be checked soon.

What the exam and any tests involve

MedlinePlus says your provider will examine the lump and ask where it is, when you first noticed it, whether it is painful, growing, bleeding or draining, whether there is more than one, and what else you have noticed. Antibiotics may be prescribed for an infection. If cancer is suspected, or the provider cannot make a diagnosis by looking, a biopsy or imaging test may be done, usually arranged through a dermatologist or surgeon. Tell the provider about any new growth, even one that seems harmless, because some skin cancers look like cystic nodules.

Sources

• MedlinePlus — Skin lumps
• MedlinePlus — Epidermoid cyst