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Moles

(Nevi)

Definition

Moles are spots on the skin where pigmented cells have clustered together. They typically appear as light to dark brown spots on the skin that are either flat or raised. Most people have benign moles, which are harmless.
Moles that become atypical are called dysplastic nevi. They may eventually become melanoma . Melanoma is a form of skin cancer.
Mole
mole
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Causes

Moles develop from pigment-producing cells in the skin called melanocytes. Normally, these cells are evenly distributed in your skin. When you have a mole, these cells have formed a cluster.

Risk Factors

Factors that may increase your chance of developing moles:

Symptoms

Most people have some benign moles that appear at birth, childhood, or adolescence. Most adults have 10-40 moles.
Benign moles, which can appear anywhere on the body, are usually:
Signs that a mole may be atypical include:
Irregular Border on Mole
Skin Cancer Sign: Irregular Border on Mole
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When Should I Call My Doctor?

If you are concerned about a mole because it looks different from the others, or you are over age 30 and notice a new mole, call your doctor. Also, call your doctor if you notice any signs that an existing mole may be atypical.

Diagnosis

Your skin will be examined. You will be asked about your symptoms and medical history.
Your bodily tissues may be tested. This can be done with a biopsy to remove all or part of the mole to be tested for cancer cells.

Treatment

Benign moles do not need to be treated. However, surgery may be done to remove those that are unsightly or irritated.
Treatment for atypical moles includes monitoring or removal. Atypical moles that are cancerous or suspected of being cancerous can be removed . The mole tissue is examined under a microscope. If cancer cells are found, more surgery is done to remove any remaining portion of the mole and surrounding tissue.

Prevention

To help prevent benign moles from becoming atypical and possibly cancerous:
To detect atypical or cancerous moles early:
Have moles removed if your doctor recommends it.

RESOURCES

American Academy of Dermatology http://www.aad.org

American Cancer Society http://www.cancer.org

CANADIAN RESOURCES

Canadian Dermatology Association http://www.dermatology.ca

Dermatologists.ca http://www.dermatologists.ca

References

Moles. American Academy of Dermatology website. Available at: http://www.aad.org/dermatology-a-to-z/diseases-and-treatments/m---p/moles. Accessed June 4, 2015.

Common Moles, Dysplastic Nevi, and Risk of Melanoma. National Cancer Institute website. Available at: http://www.cancer.gov/types/skin/moles-fact-sheet. Updated November 1, 2011. Accessed June 4, 2015.

Sunscreen FAQs. American Academy of Dermatology website. Available at: https://www.aad.org/media-resources/stats-and-facts/prevention-and-care/sunscreens. Accessed June 4, 2015.

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