Atypical Moles

What they look like:

Normal moles are usually small brown spots or growths on the skin. They can be either flat or elevated and are generally round. Moles known as dysplastic nevi or atypical moles are larger than average (usually larger than a pencil eraser) and irregular in shape. They tend to have uneven color with dark brown centers and lighter, sometimes reddish, uneven border or black dots at edge. These moles often run in families. Because they often resemble melanomas (an aggressive and deadly form of skin cancer), it is important to have them monitored by a health care provider. The presence of an atypical mole can increase the risk of developing melanoma. The level of risk increases with the number of atypical moles.

Dysplastic Nevus Syndrome:

People with dysplastic nevus syndrome are at a higher risk of developing melanoma. Those with dysplastic nevus syndrome have the following three characteristics:
  • 100 or more moles
  • One or more moles 8 mm (1/3 inch) or larger in diameter
  • One or more moles which are atypical.


  • Performing monthly self-examinations, looking for changes in the color, size or shape of their moles or the appearance of new moles is encouraged.
  • Skin examinations at least yearly by a dermatologist or other healthcare provider are recommended.
  • Depending on the amount of atypical cells found in a mole after biopsy, removal of more tissue from the surrounding area may be necessary.
  • Sunscreen and protective clothing should be used to shield moles from sun exposure.