Skin moles have had a varied reputation over the centuries, from a witch’s mark to a beauty mark. But the truth is most of us don’t think about our moles at all until there’s a problem.
Adults typically have between 10 and 40 moles, and for most people, these skin growths are harmless. But you still need to keep an eye on them, as they can develop into skin cancer.
UNC Health dermatologist Jayson Miedema, MD, answers common questions about moles.
What are moles?
“Moles are really common benign growths on the skin,” Dr. Miedema says. “They’re made of cells called melanocytes.”
Melanocytes produce melanin, or skin pigment, which is why moles are colored. You may be familiar with a mole that is a small, brown, dome-like spot that raises off the surface of the skin, but moles can also be black, blue, pink or tan. They can be flat or raised. Some are wrinkly.
Moles are typically small—less than the size of a pencil eraser—and usually have a round or oval shape. They can appear anywhere on the body.
Because moles can look different from person to person, Dr. Miedema recommends you talk to a doctor about the marks you see on your skin.
You may hear a mole referred to as a nevus, which is the scientific term.
Why do people get moles?
“Genetics determines who gets a lot of moles and who doesn’t,” Dr. Miedema says. “Most of the time, there’s not a specific cause for a mole.”
While you can be born with some moles, Dr. Miedema says they tend to appear in childhood through middle age.
“Your 30s and 40s are when you typically have the highest number of benign nevi (moles),” he says. “As you get older—in your 60s or 70s—you typically don’t get any new nevi, and if you do, you should have it checked to make sure it’s benign.”
How do moles change over time?
The moles you have in your 20s may not look like the moles you have in your 50s.
“Moles evolve and there may be subtle changes in color or shape during your lifetime,” Dr. Miedema says. “They can fade as people get older.”
While slow and subtle changes are normal, drastic changes to a mole are a reason to see a dermatologist.
When should you be concerned about a mole?
Melanoma is a type of skin cancer that begins in the melanocytes—the same cells that form moles. About 20 to 30 percent of melanomas are found in moles, while the majority are found on normal skin. Most moles aren’t cancerous, but major changes in a mole could indicate cancer.
The ABCDE rule can help you remember the characteristics of moles that should give you concern:
- A is for Asymmetrical: Moles are generally round and symmetrical, so take note if one side looks different than the other.
- B is for Border irregularity: Moles generally have smooth, defined borders; be on the lookout for jagged or blurry edges.
- C is for Color: If the mole is several different colors or changes colors, see a doctor.
- D is for Diameter: A mole that’s bigger than a pencil eraser is a concern.
- E is for Evolving: Talk to your doctor if the mole is growing, changing rapidly or if it’s itchy, bleeding or inflamed.
Some concerning moles may only have one or two of the characteristics described by the ABCDE rule, so any of those changes would be a reason to have the mole—or any patch of skin—examined by a doctor.
“Sometimes spots that aren’t nevi appear on the skin, and it can be hard to make that distinction at home,” Dr. Miedema says. “If there’s any concern about something on your skin, get it checked by a professional.”
You should see a dermatologist if you have more than 50 moles so that they can provide ongoing monitoring.
“People with a lot of moles are at an increased risk of melanoma compared to people without moles,” he says. “If you have a family history of skin cancer, establish regular care with a dermatologist.”
Your dermatologist will let you know how often you need to be seen.
What happens if a doctor is concerned about a mole?
If your doctor is concerned that a mole could be cancer, they’ll surgically remove it so it can be tested.
“We numb the area locally with anesthetic, then typically use a blade or scalpel to remove it,” Dr. Miedema says. “The lesion will be sent to the pathology lab for assessment under the microscope.”
If the test shows that the mole is cancerous, your doctor will work with you to determine next steps. Finding a cancerous mole early is always best, as treatment is likely to be less invasive; removal of the mole may be all that’s needed.
What if I don’t like the look or feel of a mole?
If a mole bothers you because of the way it looks or feels, talk to your doctor.
“There may not be a reason to remove it from a medical perspective, but it can be removed if it causes irritability or you’re bothered for cosmetic reasons,” Dr. Miedema says. “When you remove anything, there is a risk for a scar, but it can be subtle.”
Never try to remove a mole yourself. You could cause an infection or scarring.
“If you’re scratching and picking at it because you’re worried and hoping it goes away, it’s better to come in and it get it checked,” Dr. Miedema says.
Questions about your skin? Talk to your doctor. If you need a doctor, find one near you.