Q: I’ve had a mole on my arm my entire life and I’ve heard it may become cancerous. Should I be concerned?
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A: Just because you’ve had a mole or birthmark your entire life does not mean that it can’t change or become dangerous. Any kind of skin lesion is a tumor – many are benign (non-cancerous) or pre-malignant (not yet cancerous), but they are still tumors with the potential to develop into cancer.
While moles and birthmarks often remain stable for years, sometimes they change because of factors beyond a person’s control – like genetics, environmental factors, hormones or a combination of factors. I tell everyone and especially people with a large number of moles to take advantage of the technology in your pocket and take routine skin selfies to monitor skin lesions over time. The timestamp can be very helpful to dermatologists who can evaluate how the lesions have changed and make decisions about which lesions to biopsy.
You can’t completely avoid melanoma, but you can reduce your risk. Melanomas can occur anywhere on the body, and often show up on a person’s back, face, arms and legs. Some melanoma lesions can also occur in non-sun exposed areas like the bottoms of the feet, the lower abdomen or under the fingernails. The best prevention is to limit exposure to the sun’s UVA and UVB rays – think wearing SPF daily on your face and any exposed areas, wearing hats, sunglasses and protective clothing and staying out of the sun during the middle of the day (from about 10 a.m. to 3 p.m.) when the sun is at its hottest.