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What are Dysplastic Nevi (Abnormal Moles)? 

Atypical, or abnormal, moles, also known as dysplastic nevi, are unusual-looking moles that have irregular features under the microscope. Though benign, they are worth more of your attention because individuals with atypical moles are at increased risk for melanoma, a dangerous skin cancer.

An atypical mole can occur anywhere on the body. The appearance of these moles can vary greatly. The best advice is to know your skin and schedule an annual full body exam. Keep track of any and all moles you may have. This gives you the best chance to spot anything new, changing or unusual and bring it to the attention of your dermatologist.

What do I need to know about Dysplastic Nevi? 

An atypical mole is not a skin cancer but having these moles is a risk factor for developing melanoma.

Although rare, melanoma can arise in association with atypical moles. That is why it is important to be aware of these moles, get them checked by your dermatologist, and watch out for changing moles.

If you have atypical moles plus a family history of melanoma, you have an increased risk of developing melanoma.

If you have any of these common melanoma risk factors plus atypical moles, you must be particularly watchful:

  • Fair skin, light eyes or hair
  • Freckles
  • Many moles
  • A personal or family history of melanoma or nonmelanoma skin cancer
  • Photosensitivity
  • Inability to tan
  • Repeated and intermittent sunburns

It’s important to note that even without a family history of melanoma, if you have atypical moles, you have an elevated risk of developing melanoma.

How can I spot a Dysplastic Nevi? 

At first glance, it can be tricky to see how an atypical mole differs from a normal mole. Below are some warning signs to watch for.

The ABCDE Warning Signs

The first five letters of the alphabet can be used as a guide to the warning signs for atypical moles and melanoma.

A is for Asymmetry. Most melanomas and/or dysplastic nevi are asymmetrical. If you draw a line through the middle of the lesion, the two halves do not match, so it looks different from a round to oval and symmetrical common mole.

B is for Border. Borders of dysplastic nevi tend to be uneven and may have scalloped or notched edges, while common moles tend to have more smoother, more even borders.

C is for Color. Multiple colors are a warning sign. While benign moles are usually a single shade of brown, a melanoma and/or dysplastic nevus  may have different shades of brown, tan or black. As it grows, the colors red, white or blue may also appear.

D is for Diameter and Dark. While it’s ideal to detect a melanoma or dysplastic nevus when it’s small, it is a warning sign if a lesion is the size of a pencil eraser (about 6 mm, or ¼ inch in diameter) or larger. Some experts say it is also important to look for any lesion, no matter what size, that is darker than others. Rare, amelanotic melanomas are colorless.

E is for Evolving. Any change in size, shape, color or elevation of a spot on your skin, or any new symptom in it, such as bleeding, itching or crusting, may be a warning sign to see your doctor.

When in doubt, check it out: A board certified dermatologist such as Dr. Greenberg will determine whether your pigmented lesion is an atypical mole or a melanoma, and provide you with detailed information about next steps.

What Causes Dysplastic Nevi?

The precise origin of atypical moles is unknown. Some individuals are more prone to these types of moles (and moles in general) due to genetic and environmental factors (prolonged sun exposure, especially). Around 1 in 10 people will have at least one atypical mole during their lives.

What are the treatment options for Dysplastic Nevi? 

If an atypical mole is benign, no intervention is required. However, if you have one or more atypical moles, frequent monitoring is crucial to ensure that any sign of melanoma is detected and treated as early as possible. 

If your dermatologist identifies a mole as suspicious, you may need a biopsy (removing tissue from the mole for further testing). We also have ways to evaluate moles without surgically removing them. If however there is significant concern, the mole may need to be surgically removed to ensure it does not grow back.

If you have one or more atypical moles, or if you notice any of the “ABCDE” melanoma warning signs outlined above, call us at 941-282-3376 to schedule an appointment.