Your right arm could indicate your melanoma risk

Your right arm could indicate your melanoma risk

One study investigated a new method for identifying people at high risk for melanoma, a form of skin cancer.

Counting the number of moles on the right arm was found to be a good indicator of how many moles a person has on his or her entire body, researchers said. People with a high number of overall moles were at higher risk for developing melanoma.

Researchers studied 3,594 female Caucasian twins over a period of eight years and found that the right arm best predicted the total number of moles on the entire body. The right arm was also the most telling site when using data from another study that included both sexes.

“The findings could have a significant impact for primary care, allowing [physicians] to more accurately estimate the total number of moles in a patient extremely quickly via an easily accessible body part,” said lead study author, Simone Robero, of the Department of Twin Research and Genetic Epidemiology in London, in a news release. “This would mean that more patients at risk of melanoma can be identified and monitored.”

The research demonstrated that a female who had more than seven moles on her right arm was found to have nine times the likelihood of having more than 50 on her entire body. A person with more than 11 moles on her right arm was likely to have more than 100 across her entire body, putting her in the higher-risk category.

“While only 20 to 40 percent of melanoma arises from existing moles, the risk of developing skin cancer increases with each mole,” says Dr. Michael Jude Welsch, dermatologist with Advocate Christ Medical Center in Oak Lawn, Ill. “Having a quick way of determining a person’s total mole count, and keeping a closer watch on those individuals with an increased risk of developing melanoma, is beneficial for the physician and the patient.”

Dr. Welsch says it’s important to note that this is just a guide to help determine patients at higher risk, and that anyone can get melanoma, regardless of risk factors.

While this study points to 100 moles as the indicator for higher-risk, Dr. Welsch and the U.S. Preventive Services Task Force agree that just 50 moles puts a person at greater risk for melanoma. The risk also increases for people who have fair-skin, are 65 years old and older, and have atypical moles.

“It’s important to self-check your entire body and note any changes,” Dr. Welsch says. “If you notice any ABCDE criteria, see your primary care physician or dermatologist.”

ABCDE Criteria:

  • A=Asymmetry. If you draw a line down the center of the mole, each side should match or be symmetrical.
  • B=Border irregularities. A non-cancerous mole should have smooth, even borders
  • C=Color. If a mole has more than one color, it’s another warning signal
  • D=Diameter. Melanomas are usually larger than a pencil eraser but can be smaller when first detected.
  • E=Evolving. If your moles starts to change in any way – uneven coloring, size, shape, uneven edges, bleeding, itching or enlargement – it’s an indication of possible melanoma.

Related Posts


One Comment

  1. Margaret J. Johnson February 22, 2017 at 11:22 am · Reply

    What’s the medical difference between a mole and a freckle? Are moles always ‘raised’ and freckles flat and smooth?

Subscribe to health enews newsletter

About the Author

Kate Eller
Kate Eller

Kate Eller was a regional director of public affairs and marketing operations for Advocate Health Care. She enjoys road trips, dogs, minimalism, yoga, hiking, and “urban hiking.”