What does a dysplastic nevus look like?

ABCDE's of moles. Atypical moles that resemble melanoma often has one or all of the following characteristics: a for asymmetry; b for irregular borders; c for lots of different colors (or shades of brown); d for rapidly growing diameter; e for evolving or changing mole. If you have any moles with these characteristics, you should see a dermatologist.
Dark brown. A dysplastic nevus is often very dark brown and, sometimes, will have areas that are lighter than others. Biopsy is the best way of knowing if a nevus is dysplastic.