Moles are among the most common things on human skin. The American Academy of Dermatology (AAD) says almost every adult has a few, and 10 to 40 is normal. People with lighter skin often have more. Most appear in childhood and the teenage years, and they keep changing as a child grows. Having moles is normal. The work is in knowing which ones to show a dermatologist.
What a typical mole looks like
A common mole is usually one color, often brown, though moles can be tan, black, red, pink, blue, skin-toned or colorless. It is round, flat or slightly raised, and it stays the same from month to month. Your moles do not all have to look alike; they can differ in size, shape and color from one another.
Warning signs: the ABCDEs
The AAD’s ABCDEs describe a mole or spot that should be seen by a dermatologist without waiting:
- Asymmetry: one half is unlike the other.
- Border: the edge is irregular, scalloped or poorly defined.
- Color: the color varies from one area to another, with shades of tan, brown or black, and sometimes white, red or blue.
- Diameter: usually larger than 6 millimeters, about the size of a pencil eraser, though melanoma can be smaller.
- Evolving: the mole looks different from the rest, or it is changing in size, shape or color.
The ugly duckling sign
The Skin Cancer Foundation adds a second check. Compare each spot with the moles around it. A melanoma can stand out from its neighbors like an ugly duckling. This also matters because, by the Foundation’s figures, only about 20 to 30 percent of melanomas start in an existing mole. The other 70 to 80 percent appear on skin that looked normal, so a new spot deserves as much attention as a changing one.
Who is at higher risk
According to the Skin Cancer Foundation, melanoma risk rises with the number of moles. People with many moles, or many atypical moles, are at higher risk, and large moles add risk too. Other factors include a family history (about one in 10 people diagnosed has a relative who had melanoma), fair skin with red or blond hair, a history of five or more sunburns, indoor tanning, and a weakened immune system from medical treatment.
When to see a dermatologist
The AAD advises an appointment if a mole starts to grow, itch or bleed, and an immediate one for a mole with any ABCDE sign. A new mole in adulthood is also worth a visit, since the AAD notes new moles and changes in adults can be a sign of melanoma. So is a mole that grows back after it was removed. A dermatologist is the person to decide whether a mole is harmless.
What a visit involves
A dermatologist’s trained eye can often tell whether a spot is a mole. For a full skin check, the Skin Cancer Foundation describes changing into a gown and a head-to-toe exam, including the scalp, back, buttocks, behind the ears and between the toes. The dermatologist may use a dermatoscope, a handheld magnifier that shows the layers just under the surface. A mole that looks suspicious may be biopsied, which means removing part or all of it and sending it to a lab.
Bring phone photos of any mole that has changed. They help the dermatologist see what it looked like before.
How moles are removed
The AAD says dermatologists remove moles that are bothersome, such as one that rubs on clothing, ones a patient finds unattractive, and ones that are suspicious. There are two main methods:
- Surgical excision: the whole mole is cut out and the skin is stitched closed if needed.
- Surgical shave: the mole is removed with a surgical blade.
In both cases, the mole is usually examined under a microscope by a specially trained doctor. Removing a mole at home is risky: if it contains cancer, cells can stay behind and spread, and home removal can scar or get infected.
Cosmetic mole removal, listed on this page, is meant for a mole a dermatologist has already assessed. It is not a substitute for that assessment.
Self-checks and sun protection
Sunburns and indoor tanning raise melanoma risk, so avoiding both is part of lowering that risk. The Skin Cancer Foundation recommends a dermatologist skin exam once a year, more often for higher-risk people, with your own self-checks in between.
How to choose a dermatologist
Ask whether the visit is a full-body exam or a look at one mole. Ask whether they use a dermatoscope, and whether a removed mole is sent to a lab. If you want a mole removed for appearance, ask which method they would use and what the scar is likely to look like. Check with your insurer whether you need a referral and what is covered under your plan.
The city list below shows dermatologists who name moles on their own websites.