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How do you know if you have a bad mole?

Moles (also called nevi) are very common. It has been estimated that the average person has 10-40 moles. Moles are not bad in and of themselves but when they turn into cancer, they can have very serious and dangerous consequences. This type of cancer is called melanoma. Although melanomas can certainly be cured, especially if caught in the early stages, they can potentially spread throughout the body and even be fatal if not treated properly.

A good rule of thumb for examining your moles is the ABCDE rule.

Asymmetry: When you fold a mole in half it should be the same on both sides,
Border: The edges of a mole should not be irregular, scalloped or poorly defined
Color: The color should be regular; often tan or brown but not black or multicolored
Diameter: Melanomas are often, but not always larger than 6 mm (the size of a pencil eraser)
Evolving: Moles that change are more concerning especially if they are developing any of the other ABCD characteristics

So what can you do? To prevent moles from turning into cancer it is important to protect yourself from the sun: wear sunscreen, avoid high intensity direct sunlight, wear sun protective clothing, and do not use indoor tanning salons. Skin examinations once or twice a year are the best way to find cancerous moles at early stages, before they progress into later stage disease that can have more serious consequences.

At Brookside Dermatology Associates we are experts in the diagnosis and treatment of skin cancer. If you have any questions or concerns about spots on your skin come in for an evaluation.

Jeremy Moss, M.D. Ph.D. Dr. Jeremy Moss, a board certified dermatologist, is an associate professor of dermatology at Yale University and on the active medical staff at St. Vincent’s Medical Center.

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