A dysplastic nevus (atypical mole) is a type of mole that may appear similar to melanoma, but is not melanoma. They often have an irregular shape (not round) and may have more than one color within the same mole. They can occur anywhere on the body, but are most often on the trunk, and rare on the face.
In order to confirm the diagnosis of a dysplastic nevus, and to differentiate between this and a melanoma, a biopsy is performed. The dysplastic nevus is then graded as mild, moderate or severe. Often, mild or moderately dysplastic nevi require no further treatment after the biopsy has been performed. Severely dysplastic nevi, however, are typically treated as early melanoma with an additional surgical excision to ensure complete removal, as they share many features with early melanoma.
If you have been diagnosed with a dysplastic nevus you have a greater risk of developing melanoma. For this reason, daily sun protection is important as well as monthly self skin exams to monitor for changes and annual full skin exams by a dermatologist. This is particularly important if you have many moles throughout your body.