Does the color of your fingernails indicate your risk for cancer?
A recent story in the British press asked whether brown or black streaks under the fingernails could be an indicator of subungual melanoma, a specific type of skin cancer that lives in the nail bed. As usual, these kinds of stories cause a lot of anxiety, so we asked the experts.
“Subungual melanoma is a rare and often deadly type of melanoma,” says Dr. Dendy Engelman of Manhattan Dermatology and Cosmetic Surgery. “This specific type of melanoma that occurs under the nail has fairly classic clinical findings—with linear, darkly pigmented streaking of the nail and involvement of proximal nail fold or cuticle.” Further, she recommends, do take note if you see such markings. “Any pigmented streaking of the fingernail should be evaluated,” she says.
However, Dr. Engelman continues, nail color is not itself an indication of subungual melanoma nor a reason to believe you may have other types of melanoma. “Determining one’s risk factor for melanoma solely on the color of the nail plate is neither helpful nor vetted in science. There are many causative factors that can lead to discoloration in the nail. Melanoma of the nail does not mean nor predict that you will have melanoma else where on the body, either.”
So, while some streaks beneath fingernails may be a sign of this one specific type of melanoma, fingernails are not an indicator of overall skin health, so it’s important to be alert for other signs and symptoms, too, and get regular checks by your dermatologist.
Most primarily, since you know your body best, it’s to be vigilant about doing skin checks on your own body in order to catch potential skin cancer early, says Dr. Cecilia Larocca, a dermatologist at Dana-Farber Cancer Institute. She recommends that patients at a high risk for melanoma, or those who have already had skin cancer, examine their own body once a month and look for the “ABCDE” indicators in moles: Asymmetry, irregular boarders, multiple colors, diameter larger than 6 millimeters, and evolution, which means a mole that changes or grows over time.
These moles are not always melanoma, she continues, but it’s important to get checked out by your dermatologist if you have any suspicious-looking spots on your body. This particularly applies to people who are at higher risk for melanoma, which, as Dr. Engelman tells us, includes people with fair skin, a personal history of indoor tanning, family history of melanoma and those who burn rather than tan in UV exposure, among other factors.