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Benign Skin Conditions
Moles and Melanocytes
Nevi, or more commonly known as moles, are growths on the skin. These growths occur when cells in the skin, called melanocytes grow in a cluster with tissue surrounding them. Moles are usually pink, tan, brown or flesh-colored.

Moles are very common. Most people have between 10 and 40 moles. Until about age 40, a person may develop new moles from time to time. Moles can be flat or raised. They are usually round or oval and no larger than a pencil eraser. Many moles begin as a small, flat spot and slowly become larger in diameter and raised. Over many years, they may flatten again, become flesh-colored and go away.

Melanocytes also are spread evenly throughout the skin and produce the pigment that gives skin its natural color. When skin is exposed to the sun, melanocytes produce more pigment, causing the skin to tan, or darken.

Dysplastic Nevi
About one out of every ten people has at least one unusual mole. These aytpical moles are called dysplastic nevi and are more likely than ordinary moles to develop into a type of skin cancer called melanoma. Because of this, moles should be checked regularly by a physician or nurse, especially if they look unusual, grow larger, change in color, outline, or change in any other way.