Moles (Nevi)

Moles are clusters of pigmented cells. They are found on the outer layer of the skin, the epidermis. (Read about "Skin") Almost everyone has moles on their skin. The American Academy of Dermatology (AAD) says the average is between 20 and 40 moles by the time we reach adulthood. Sometimes moles are referred to as beauty marks. Most moles are benign but some can turn cancerous so people should be aware of changes in their moles or any new moles.

The medical term for a mole is a nevus, with the plural being nevi. Most moles or nevi appear as a dark brown spot. Some are raised and some have hair on them. Most will never be a problem but they also can turn into skin cancer (Read about "Skin Cancer") and because of that, it's important to remember the ABC's of moles as warning signs. They are:

• Asymmetry - If one half of the mole doesn't match the other half
• Border - If the borders are uneven or ragged
• Color - If the color of the mole isn't even or if there are a number of colors in the same mole.
• Diameter - If the mole is larger than a pencil eraser

If you have a mole that falls into any of those categories, you should discuss it with your doctor.

Moles tend to darken with sun exposure. Sun also tends to increase the number of moles. This is another reason for avoiding excess sun exposure by both adults and children. (Read about "Children and Sun")

There are different types of moles:

• Acquired nevi - These are the moles that develop in childhood and as we get older. Most people are not born with any moles but develop them as they age.
• Congenital nevi - In about one in 100 births however, the baby does have moles at birth. These are called congenital nevi, according to AAD. These are often called birthmarks. Depending on how large they are, they can be called large or giant nevus. Large nevi are defined as over 4 inches and happen in about one in every 20,000 births, according to the Nevus Network (NN). There are usually a number of smaller nevi on the body as well. Giant nevi cover much of the body and are rare, according to NN, occurring once in 250,000 to half a million births. These types of congenital moles should not be confused with vascular birthmarks such as port wine stains. (Read about Vascular Birthmarks)
• Dysplastic or atypical nevi - There is also a type of mole called dysplastic nevi or atypical moles. They are not round but irregular in shape with uneven borders and larger in size. They also tend to be different colors, being brown toward the center and reddish at the edges.

AAD says people who are born with moles or nevi are at greater risk for developing skin cancer, particularly melanoma, the deadliest form. Protective measures - such as avoiding the midday sun and using sunscreen - should be followed. (Read about "Sunscreen")

Moles that are located in areas where they may get irritated, for example at the collar line or near beard growth, can be removed. Depending on the size and location of the mole, it can be shaved off or it can be excised with an area of surrounding skin and then stitched. (Read about "Plastic Surgery") If the mole is suspicious in appearance, it can be tested or biopsied for cancer. (Read about "Biopsy")

Related Information:

    Skin Care

    Age and Skin