Nail Clinic: Moles and Melanoma
We answer your most common mole-related questions so you can make safe choices when you spot a suspicious-looking mole at your station or on your own body.
Q: How and when do moles develop?
A: Moles are hereditary, so your genetics largely determine how many you’ll have and where you’ll have them. Other factors that may play a role include skin color and amount of sun exposure. According to the American Academy of Dermatology (AAD), the dark color of moles is caused by melanocytes, which are cells that produce the pigment melanin—the same pigment that determines an individual’s skin color and tans the skin after sun exposure. These pigmented spots develop throughout a person’s life, most starting relatively soon after birth. “Moles tend to grow over a lifetime—it’s very unusual to see them at birth, but they typically start to grow within the first five years of life,” says Joel Schlessinger, M.D., a board-certified dermatologist whose Omaha, Nebraska-based practice includes a full-service day spa. “Interestingly, moles sometimes disappear as one ages.” They also tend not to appear after age 40 or 50, he says. Robert T. Brodell, M.D., professor of internal medicine, dermatology, at Northeastern Ohio Universities College of Medicine in Rootstown, Ohio, explains the life cycle of a typical mole: Pigmentation begins between the ages of 5 and 10 when the mole is a flat brown lesion that’s smaller than a pea, at which point it’s called a junctional nevus. It then rises for the next 5 to 10 years—a compound nevus. Over the course of several decades it will continue to rise as an intradermal nevus.
Brodell further explains, “Moles that a person is born with are called congenital melanocytic nevi, or birthmark moles, and are more likely to turn into melanoma skin cancer; they should be either removed or watched carefully.” Regardless of type or stage of progression, moles can take on a variety of appearances with different people. “The size of a mole and its characteristics—whether it’s raised or flat, how dark the color is, whether it’s multicolored and whether hair grows on it—vary from person to person and can even vary on the same person, depending on the area where it’s located,” explains Raffy Karamanoukian, plastic surgeon and assistant clinical professor in the Department of Plastic Surgery at the University of California, Irvine. “They usually change gradually and uniformly.” When nonuniform and/or sudden changes take place in a mole, there may be a problem.