Patient education: Seborrheic keratosis (The Basics)
Written by the doctors and editors at UpToDate

What is seborrheic keratosis?

Seborrheic keratosis, or "SK, " is a benign growth of the skin. "Benign" means not cancerous. SK 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. 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 1 or many of these growths. If there are more than 1, they are called "seborrheic keratoses."

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