Seborrheic keratoses can look like melanoma, the deadly skin cancer.
These benign lesions can come in a variety of colors, sizes and shapes, and can raise concern if you just happen to discover one or a few on your skin.
Seborrheic keratoses can easily be identified by a dermatologist and have several classic features.
One such feature of seborrheic keratoses is that it can resemble skin cancer, including melanoma.
There are two questions to consider.
1 Can skin cancer or melanoma arise from the cells of a seborrheic keratosis?
2 Is a seborrheic keratosis more likely to develop into melanoma when compared to regular areas of skin?
“Seborrheic keratoses represent a normal thickening of the skin,” says Adam J. Mamelak, MD, a board certified dermatologist and founder of Sanova Dermatology in Austin, TX.
They can appear to be stuck onto the skin in the way that a little speck of dirt or clay can be stuck on. But not all appear that way.
They may resemble warts, but a seborrheic keratosis does not contain the virus that causes warts, the human papilloma virus.
A seborrheic keratosis that develops or progresses can begin to look like a wart, with a lot of unsightly texture.
On the other hand, some can appear like glossy tiny droplets, which can be flesh colored, pinkish or some shade of brown, with a smooth surface.
These lesions may, or may not, itch. You may never know you have them unless you just happen to visually discover them upon, for example, adjusting your bra strap in the mirror, and you see a few speckles on your skin that you didn’t notice before.
They can appear just about anywhere and usually begin appearing after age 40.
“Their development is most often genetic,” says Dr. Mamelak. “If your parents have them, there’s a good chance you’ll get them as well.
“Often called age or liver spots, seborrheic keratoses are completely benign.” In short, their cells are not atypical.
But we need to dig deeper here. The cells that make up a seborrheic keratosis are perfectly normal — but can they ever become cancerous?
Dr. Mamelak explains, “The skin cells that make up a seborrheic keratosis can become malignant, just as they can in normal skin.
“That is, a skin cancer can arise within a seborrheic keratosis the same way it can arise in normal-appearing skin.”
This shouldn’t be surprising, because these benign skin barnacles are MADE UP OF SKIN.
As for their likelihood of turning cancerous when compared to surrounding skin, Dr. Mamelak says, “The risks for a skin cancer arising anywhere are the same: history of excessive sun exposure and sunburns, fair skin and complexion, personal and/or family history of a skin cancer.”
If one of these skin growths is scratched, it can bleed. Do not take this to mean a sign of melanoma or other cancer.
“And while some consider them unsightly, or they can catch or rub on clothing and become painful and irritated, there is no reason to treat them unless they become symptomatic,” says Dr. Mamelak.
“Just as you should be mindful of a non-healing or changing lesion on your skin, if a seborrheic keratosis starts to change in appearance, bleeds or changes color, it should be evaluated.”
Otherwise … you may as well just leave them be, unless the itching gets annoying; they interfere with clothes; or they become a cosmetic issue. They can be removed via liquid nitrogen by freezing.
A scar may result from the new skin, growing in after the removal, having different pigment concentrations than the original skin.
If you are not sure you have a seborrheic keratosis, and keep wondering if it might be melanoma or some other kind of skin cancer, make an appointment with a dermatologist. The peace of mind will be worth it.
Dr. Mamelakfocuses on the full breadth of dermatologic care, from cosmetic skin solutions to advanced skin cancer removal. He’s founder of the Austin Mohs Surgery Center, which is dedicated to the treatment and management of skin cancer.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.