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    • Services and providers for Moles in the U.S.
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Also called: Nevus

Moles are growths on the skin. They happen when cells in the skin, called melanocytes, grow in a cluster with tissue surrounding them. Moles are very common. Most people have between 10 and 40 moles. A person may develop new moles from time to time, usually until about age 40.

Moles are usually pink, tan or brown. They can be flat or raised. They are usually round or oval and no larger than a pencil eraser.

About one out of every ten people has at least one unusual (or atypical) mole that looks different from an ordinary mole. The medical term for these unusual moles is dysplastic nevi. They may be more likely than ordinary moles to develop into melanoma, a type of skin cancer. Because of this, you should have a healthcare professional check your moles if they look unusual, grow larger, change in color or outline, or in any other way.

National Cancer Institute

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