Melanoma Mimics Introduction
A variety of melanocytic and non-melanocytic skin lesions may bear clinical and/or histologic resemblance to melanoma. Specific subtypes of benign melanocytic nevi may suggest melanoma. Most benign nevi are symmetric, sharply defined, less than 6 mm in greatest diameter, usually have one dominant color, and are usually asymptomatic. Roughly 30-50% of melanomas arise in pre-existing melanocytic lesions. Nevi that develop symptoms and change in appearance are suspicious.