The first sign of melanoma is any change in the size, shape, color, or feel of an existing mole. It may also appear suddenly as a new mole. Some people have certain abnormal-looking moles which are called dysplastic nevi. This is why it is recommended that you have any mole that changes in appearance be checked by your dermatologist for proper evaluation. It is also important to know the ABCDEs of melanoma: asymmetry, border, color, diameter and elevation. Any changes in these parameters warrants further evaluation.
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