Moles, formally known as nevi, are pigmented growths that can appear on almost any part of your body. Although they are typically harmless, in certain circumstances moles can contain cells that turn into a dangerous form of skin cancer called melanoma. You cannot prevent skin moles from forming; however, you can take steps to prevent moles from developing into cancer.
Understanding Moles
Moles form when pigment cells called melanocytes cluster together abnormally rather than dispersing evenly throughout your skin, the Mayo Clinic reports. Doctors do not know the underlying causes of this clustering. The vast majority of people have at least a few moles, according to the American Academy of Dermatology, or AAD. If you have relatively light skin, you will typically have more moles than individuals with relatively dark skin. In most cases, moles form in childhood or later life, but some people also have moles on their bodies at birth.
Melanoma
Melanoma can form either inside or near mole tissue, the AAD reports. If you have moles that developed after birth, you typically have low risks for associated cancer development; however, your chances for melanoma increase if you have more than 50 to 100 of these normal moles. You also have increased risks for melanoma if you have any number of moles that are irregularly shaped or larger than the size of a pencil eraser. In addition, you have increased melanoma risks if you were born with a mole larger than 20 centimeters in diameter.
Mole Monitoring
You can help prevent or detect cancerous changes in your moles by monitoring their condition once a month, according to the Mayo Clinic. Begin by familiarizing yourself with the position, size and color of all the moles on your body. Since moles can form almost anywhere, you will need to check yourself thoroughly in areas that include your feet, armpits, scalp, genitals, palms, fingernails and the undersurfaces of your breasts. In some cases, you may need to have someone check hard-to-reach areas for you or use a mirror to access awkward locations. If you have types of moles known to increase your risk of cancer, increase your preventive measures by having a qualified dermatologist examine your skin for you.
Additional Steps
In addition to monitoring your moles, the Mayo Clinic recommends several measures to help prevent the development of melanoma. Begin by limiting your sun exposure whenever possible, especially between the late morning and mid-afternoon, when the sun's rays are strongest. When you do expose yourself to sunlight, prepare 20 minutes in advance by coating your skin with a sunscreen that has a minimal SPF, or sun protection factor, of 15. Reapply sunscreen at least every two hours. Whenever possible, wear clothing that protects you from direct sunlight.
Considerations
If a new mole forms on your body or you notice changes in an existing mole, the AAD recommends consulting a skin specialist. Even if you do not notice any changes or have normal moles, you may want to consider having a specialist examine your skin at least once a year. This is particularly true if you have other known skin cancer risks.
