What is seborrheic keratosis? — Seborrheic keratosis (called "SK" here) is a condition that causes growths on the skin. It usually happens in people older than 50, but younger people also get it. The growths can look like something that was stuck on the skin (picture 1). They can be light tan, brown, or black. It is usually easy to see where normal skin ends and the growth starts. The growths sometimes look scaly.
A person can have one or many of these growths. If there are more than one, they are called "seborrheic keratoses."
What are the symptoms of seborrheic keratosis? — The growths in SK often do not cause any symptoms, but they sometimes itch. They are most common on certain parts of the body. These include the:
Trunk – Chest, belly, and back
Should I see a doctor or nurse? — SK is common in older people. It is not skin cancer. But some people who get SK also get skin cancer. If you notice any new growths on your skin, ask your doctor or nurse to check them. He or she can make sure they are not cancer or treat them if they are.
Is there a test for seborrheic keratosis? — No, there is no one test. The doctor or nurse will do an exam and check your skin. He or she can usually tell if you have SK by looking at any skin changes and touching them.
If the doctor is not sure whether SK is causing the skin changes, you will have a test called a "biopsy." During a biopsy, a doctor takes a small sample of the SK or takes off the whole growth. Then another doctor looks at the tissue under a microscope to check for skin cancer.
The doctor can also do a test called "dermoscopy." In this test, he or she looks at the skin with a small microscope that has a light on it. The doctor holds this over the area with skin changes. The microscope and light help the doctor see under the skin. It can help show if a spot is SK or something else.
How is seborrheic keratosis treated? — Most people with SK do not need treatment. But if the growths bother you or look bad, a doctor or nurse can usually take them off with:
Liquid nitrogen – This is a special liquid that gets very cold. It can leave an area of lighter skin where the SK was.
A scalpel or other small tool – The doctor or nurse can take off the SK after numbing the skin. He or she might then freeze the SK with liquid nitrogen to get rid of abnormal tissue under it.
Electricity – The doctor can use electricity to burn away the SK after numbing the skin. He or she might take off the SK first and then use electricity to get rid of abnormal tissue under it.
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This topic retrieved from UpToDate on: Mar 30, 2020.
Topic 83445 Version 4.0
Release: 28.2.2 - C28.105
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