Many people have moles—they’re those little brown, tan or flesh-colored spots that pop up over the years, especially if you have fair skin. Moles, nevi, are simply clusters of skin cells called melanocytes. While moles are technically cell overgrowths, like tumors, they’re almost always harmless. But how to know when to be concerned about a mole, and when might it need to be removed?

A visit to the dermatologist isn’t just for skin health; it’s a chance to keep an eye on these spots with regular screenings. Dermatologists use certain criteria to decide if a mole needs further attention. Have your questions answered by a board-certified dermatologist at THE CENTER for Advanced Dermatology. Appointments can be conveniently scheduled online at WEBSITE or by calling 602-867-7546. 

Dermatologists look for specific signs that indicate a mole might need a closer look. This is where the ABCDE rule comes in:

  • A is for Asymmetry: Moles are usually balanced all the way around—if you split one in half, both sides would match.   If a mole is asymmetrical, it may be a sign of skin cancer. 
  • B is for Border:  Regular moles are clearly defined on the skin. Moles with blurred, jagged or otherwise difficult to define borders may be cause for concern. A scalloped shaped mole may indicate irregular cell growth that will likely require a biopsy.
  • C is for Color: Most will be consistent with one color, usually brown, tan or even black; if the color of the mole is irregular such as red, white or blue, your dermatologist could determine these are warning signs of skin cancer.
  • D is for Diameter: Normal moles are no bigger than the size of a pencil eraser. If a mole is larger, it may require attention.
  • E is for Evolving: Changes in a mole’s size, shape, color or if it starts itching or bleeding are big red flags.

Moles come in a few common types and while most are harmless, some can potentially lead to serious issues if they change or grow abnormally. Here’s a breakdown of the most common mole types and what to watch out for:

  1. Congenital Moles
  • Description: Present at birth or appear shortly after, congenital moles range in color from light tan to dark brown and can vary in size.
  • Risk Level: Generally low. However, larger congenital moles (especially those over 20 cm) have a slightly increased risk of developing melanoma later in life.
  1. Acquired Moles
  • Description: These are the typical moles that appear in childhood or adolescence, often due to sun exposure or hormonal changes. They’re usually small, round and evenly colored in shades of brown or black.
  • Risk Level: Low risk. These moles are usually benign, but as with any mole, changes in color, size or shape should be monitored.
  1. Atypical Moles
  • Description: Also called dysplastic nevi, these are larger, irregularly shaped moles with uneven color and ragged or blurred borders. They may look quite different from other moles on the body, often with varied shades of brown, tan, pink or red.
  • Risk Level: Moderate to high. Dysplastic nevi have a higher potential to develop into melanoma, especially if they undergo changes in size, shape or color. People with multiple dysplastic nevi also have an increased risk and should monitor these moles closely with regular dermatology checkups.
  1. Spitz Nevi
  • Description: These are pink, raised and dome-shaped moles that may resemble melanoma under the skin’s surface. They are most common among children and young adults.
  • Risk Level: Typically low but can be hard to distinguish from melanoma without a biopsy. If a Spitz nevus changes or exhibits suspicious characteristics, removal and examination may be necessary to rule out cancer.