PreventionBy Mayo Clinic staff
Watch for changes
The best way to catch potential problems at an early stage is to become familiar with the location and pattern of your moles. Examine your skin carefully on a regular basis — ideally once a month, especially if you have a family history of melanoma — to detect early skin changes that may signal melanoma.
Remember to check areas that aren't exposed to sunlight, including your scalp, armpits, feet (the soles, toenails and between the toes), palms and fingernails, genital area and, if you're a woman, the skin underneath your breasts. If necessary, use a hand-held mirror along with a wall mirror to scan hard-to-see places, such as your back. People with dysplastic nevi are at greater risk of developing malignant melanoma and may want to consider having a dermatologist check their moles on a regular basis.
To detect melanomas or other skin cancers, use this A to E skin self-examination guide:
- A is for asymmetrical shape. Look for moles with irregular shapes, such as two very different-looking halves.
- B is for irregular border. Look for moles with irregular, notched or scalloped borders — the characteristics of melanomas.
- C is for changes in color. Look for growths that have many colors or an uneven distribution of color.
- D is for diameter. Look for growths that are larger than about 1/4 inch (6 millimeters).
- E is for evolving. Look for changes over time, such as a mole that grows in size or that changes color or shape. Moles may also evolve to develop new signs and symptoms, such as new itchiness or bleeding.
Prevent skin cancer
In addition to periodically checking your moles, you can take measures to protect yourself from cancerous changes:
- Avoid peak sun times. It's best to avoid overexposure to the sun, but if you must be outdoors, try to stay out of the sun from 10 a.m. to 4 p.m., when ultraviolet (UV) rays are most intense.
- Use sunscreen. Thirty minutes before going outdoors, apply sunscreen with a sun protection factor (SPF) of at least 15. Reapply every two hours, especially if you're swimming or involved in vigorous activities. And keep in mind that sunscreen is just one part of a total sun protection program.
- Cover up. Broad-brimmed hats, long sleeves and other protective clothing also can help you avoid damaging UV rays. You might also want to consider clothing that's made with fabric specially treated to block UV radiation.
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- What you need to know about moles and dysplastic nevi. National Cancer Institute. http://www.cancer.gov/cancertopics/wyntk/moles-and-dysplastic-nevi/allpages/print. Accessed Sept. 13,2011.
- Nevi and malignant melanoma. In: Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 5th ed. Edinburgh, U.K.; New York, N.Y.: Mosby Elsevier; 2010.http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-7234-3541-9..X0001-6--TOP&isbn=978-0-7234-3541-9&uniqId=230100505-57. Accessed Sept. 14, 2011.
- Moles in children: What parents should know. American Academy of Dermatology. http://www.skincarephysicians.com/skincancernet/moles_children.html. Accessed Sept. 13, 2011.
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- Step-by-step self-examination. Skin Cancer Foundation. http://www.skincancer.org/step-by-step-self-examination/Print.html. Accessed Sept. 14, 2011.
- Prevention guidelines. Skin Cancer Foundation. http://www.skincancer.org/prevention-guidelines/Print.html. Accessed Sept. 14, 2011.