SkinCancerNet Article
Atypical Moles: How to Recognize

Dermatologists refer to atypical moles as “dysplastic nevi.”

Dysplastic – Alteration in the size, shape, and organization of cells

Nevus (pl. nevi) – Mole

Moles are labeled atypical, or dysplastic, due to size, shape, or color. Dysplastic nevi are usually larger than common moles, have indistinct borders (or a fried-egg appearance with distinct borders), and range in color from tan to dark brown. Such moles usually begin to appear on the skin around age 5.

Dysplastic nevi also indicate an increased risk for developing melanoma, and this risk increases when:

• There is a family history of melanoma

• Numerous dysplastic nevi are present

• The skin is light-colored and heavily freckled due to excessive sun exposure

Following are photos of patients with atypical moles. These photos also illustrate the “ABCDs of Melanoma Detection,” which are:

A – Asymmetrical. Dysplastic nevi tend to be asymmetrical. If the lesion were folded in half, the two parts would not match.
B – Border irregular. The borders tend to be poorly defined or have a fried-egg appearance.
C – Color varies. An atypical nevus tends to have more than one visible color.
D – Diameter. While melanomas are usually greater than 6 millimeters (size of a pencil eraser) in diameter when diagnosed, they can be smaller. If you notice a mole different from others, or which changes, itches, or bleeds even if it is smaller than 6 millimeters, you should see a dermatologist.

If you have a mole that has any of the ABCD characteristics or looks like any of those shown in these photos, it is probably a dysplastic nevus and should be examined by a dermatologist.

(Photos used with permission of the American Academy of Dermatology
National Library of Dermatologic Teaching Slides)

An educational program brought to you by the American Academy of Dermatology.