Moles (Nevi)

En Espaol (Spanish Version)

Definition

Moles are small growths on the skin that develop from pigment-producing cells in the skin called melanocytes. 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 (dysplastic nevi) can eventually become melanoma (a form of skin cancer). It may be hard even for experts to distinguish atypical moles from melanoma, so moles which change or look atypical need to be evaluated by a dermatologist.

Causes

Benign moles develop from an excess accumulation of melanocytes. In rare cases, a benign mole, especially one that is large and varied, may turn into an atypical mole.

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.Risk factors include:

  • Moles present at birth (This increases the likelihood of more moles later in life.)
  • Family members who have moles
  • Excessive exposure to sunlight, especially sunburn

Symptoms

Most people have some benign moles that appear at birth, or during childhood or adolescence.

Benign moles, which can appear anywhere on the body, are usually:

Dark brown, but can also be yellow-brown or flesh toneOne colorRound or oval with distinct edgesFlat and smooth, but may occasionally become raised, rough, grow hair, or change color over time Signs that a mole may be atypical include: Sudden change in size, color, shape, texture, or sensation Large size ( inch or more across, about the size of an eraser at the end of a pencil) Remember though that many melanomas today are found when quite small, often even less than inch. While the majority of atypical moles of any size are not cancerous, dont let small size keep you from seeking medical attention for a changing or irregularly shaped mole.A mixture of colors, often including blackIrregular edges Abnormal surface that is: ScalingFlakingOozing liquidBleedingOpen with a sore that won't healHard and raised lumpItchy, tender, or painfulAbnormally colored skin around it Irregular Border on Mole 2008 Nucleus Medical Art, Inc. DiagnosisThe doctor will examine your skin and moles and ask about your symptoms and medical history. Tests may include: Biopsy removal of all or part of the mole to be tested for cancer cells TreatmentBenign moles do not need to be treated. However, surgery may be performed to remove those that are unsightly or irritated.
Treatment for atypical moles include: SurgeryAtypical moles that are cancerous or suspected of being cancerous can be removed surgically with local anesthesia. The mole tissue is examined under a microscope. If cancer cells are found, additional surgery is performed to remove any remaining portion of the mole and surrounding tissue. Prevention To help prevent benign moles from becoming atypical (and possibly cancerous): Avoid excessive exposure to the sun. Take proper precautions when in the sun: Wear a broad-brimmed hat and protective clothing.Wear sunscreen with a minimum sun protection factor (SPF) of 15. Reapply sunscreen every two hours during long periods of sun exposure. Sometimes there is no way to prevent a benign mole from becoming atypical or cancerous. The key to successful treatment is early detection. To detect atypical or cancerous moles early: Monitor your moles, especially atypical moles.Report any sudden changes in a mole to your doctor. Have your doctor check and monitor atypical moles every 12 months. Have them checked more frequently based on your doctors recommendation if you have: A large number of atypical molesA family or personal history of atypical moles that develop into melanomaHave an atypical mole removed if your doctor suggests it.
RESOURCES: American Academy of Dermatologyhttp://www.aad.org American Cancer Societyhttp://www.cancer.org CANADIAN RESOURCES: Canadian Dermatology Associationhttp://www.dermatology.ca Skin Cancer Guidehttp://www.skincancerguide.ca References: American Academy of Dermatology website. Available at: http://www.aad.org . The Merck Manual of Medical InformationHome Edition . Simon and Schuster, Inc; 2000. National Cancer Institute website. Available at: http://www.cancer.gov/ . Last reviewed February 2008 by Ross Zeltser, MDPlease be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
1 2 3 4 Next
Print Article