An epidermoid cyst, often incorrectly referred to as a sebaceous cyst, is a small noncancerous lump in the top layers of the skin. It's filled with keratin, the same proteins that make up your hair and nails. These cysts grow slowly. They can grow anywhere on the body. But they are most often found on the face, behind the ears, and on the chest, trunk, upper back, scrotum, and genitals.
How to say it
ehp-ih-DER-moid sihst
What causes an epidermoid cyst?
In most cases, epidermoid cysts occur for no known reason in any gender at any age, though they are more often seen in adults. Sometimes an epidermoid cyst may occur because of skin trauma, irritation of the skin or hair follicle, chronic sun damage, or genetics.
Symptoms of an epidermoid cyst
An epidermoid cyst is a bump under the skin. It may be yellow or skin-colored. It often has a small black mark in the middle of it, like a blackhead.
An epidermoid cyst rarely causes pain, unless it breaks open (ruptures) or becomes inflamed or infected. It may ooze keratin, a white, cheesy, smelly material. If the cyst becomes inflamed or infected, it may be:
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Bad smelling.
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Red.
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Swollen.
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Sore and tender to touch.
Treatment for an epidermoid cyst
Many epidermoid cysts don’t cause any problems. They don’t always need to be treated. They may go away on their own. Treatment may be needed if the cyst becomes inflamed or infected or is in an uncomfortable place. Treatment options include:
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Steroid injection. A steroid may be injected into the cyst. This may help ease redness and pain caused by inflammation.
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Antibiotics. In some cases, you may need to take an oral antibiotic to treat infection and reduce inflammation.
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Surgical removal. The cyst can be cut out. Inflamed cysts are hard to remove. They may need to be drained or treated with antibiotics or steroids before surgery. In such cases, there is a slight chance the cyst may come back.
When to get medical care
Contact your health care provider or get medical care right away if you have:
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A fever of 100.4°F (38°C) or higher, or as directed by your provider.
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Redness, swelling, or fluid leaking from your incision that gets worse.
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Pain that gets worse.
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Symptoms that don’t get better or that get worse.
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New symptoms.
Author: Semko, Laura
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