What is skin cyst?

A skin cyst is a lump just under the skin. These cysts can form when a hair follicle becomes blocked. They are common in acne and may occur on the face, neck, back, and genitals. But they can form anywhere on the body. These cysts aren't cancer, and they don't lead to cancer. They tend not to hurt, but they can sometimes become swollen and painful. They also may break open (rupture) and cause scarring.

These cysts may not cause problems. They may not need treatment. If a cyst is swollen and hurts, the doctor may inject it with a medicine or treat it with antibiotics if it's infected. But sometimes a painful or infected cyst will need to be removed or opened. In those cases, the doctor will use numbing medicine and then will cut into the cyst to drain it or remove it.

An epidermal (skin) cyst is a small, round lump in the top layer of skin called the epidermis. It may be filled with a soft, yellow substance called keratin. Skin cysts most often appear on the face, ears, back, or chest. But they can appear on almost any part of the body.

When you have a skin cyst, the lump or bump under the skin is:

• Small, round, and smooth.
• About the size of a pea, or a little smaller or larger.
• Yellow, white, or skin-colored. It can turn red if it becomes inflamed.
• Painless. But it can be painful if it's inflamed.

• Do not squeeze the cyst or poke it with a needle to open it. This can cause swelling, redness, and infection.
• Always have a doctor look at any new lumps you get to make sure that they are not serious.
• If you had stitches, you may get other instructions. You will have to come back to have the stitches removed.