What is Seborrheic Keratoses
Although Seborrheic Keratoses (seb-o-REE-ick Ker-ah-TOE-sees) are often confused with warts, they are quite different. Seborrheic keratoses are non-cancerous growths of the outer layer of skin. There may be just one growth, or many which occur in clusters. They are usually brown, but can vary in color from light tan to black. They vary in size from a fraction of an inch in diameter to larger than a half-dollar. A main feature of seborrheic keratoses is their waxy, “pasted-on” or “stuck-on” look. They sometimes look like a dab of warm brown candle wax that has dropped onto the skin.
What causes seborrheic keratoses?
We do not know the exact cause of seborrheic keratoses. However, almost everybody will eventually develop at least a few of these growths. They are sometimes referred to as “barnacles of old age”. These become more common and more numerous with advancing age. Some people develop many over time, while others develop only a few. Sometimes seborrheic keratoses may erupt during pregnancy, following estrogen therapy, or in association with other medical problems.
Where do they appear?
Seborrheic keratoses are most often found on the chest or back, although, they can also be found on the scalp, face, neck, or almost anywhere on the body. They appear less often below the waist. Since they are not caused by sunlight, they can be found on sun-exposed or covered areas. When they first appear, the growths usually begin one at a time as small rough, itchy bumps. Eventually, they thicken and develop a rough, warty surface.
Can anyone get seborrheic keratoses?
Children rarely develop seborrheic keratoses. Although seborrheic keratoses may first appear in one spot and seem to spread to another, they are not contagious. As people age they may simply develop a few more.
How serious are they?
Almost everybody gets at least a few of these growths. Unless they develop suddenly, seborrheic keratoses does not indicate a serious health problem, and is not related to skin cancer. They may be unsightly, especially if they begin to appear on the face. They can get irritated by clothing rubbing against them. Because they may grow larger over the years, removal is sometimes recommended especially if they itch, get irritated, or bleed easily. A seborrheic keratosis may turn black and may be difficult to distinguish from skin cancer. Sometimes such a growth must be removed and studied under a microscope to determine if it is cancerous or not.
Can they be prevented?
Salves, ointments, and medications can neither cure nor prevent seborrheic keratoses.
How are they treated?
Most often sebhorrheic keratoses are treated by one of three methods. One method is called cryotherapy, or freezing. A very cold liquid called liquid nitrogen is applied to the growth with a cotton swab or spray gun to freeze it. Blisters may form under the growth that dry into a scab like crust. The keratosis usually falls off within a few weeks. No mark is usually left, although occasionally there may be a small dark or light spot. These will fade over time.
Another method is called curettage. The growths are removing by “curetting” or scraping them from the surface of the skin. An injection or spray is first used to numb the growth us removed. No stitches are necessary and bleeding is very limited. It can be controlled by applying pressure or by the application of a blood-clotting chemical.
Electrosurgery is another form of treatment. The growth is first numbed, then burned using an electric current and then scraped off.
What seborrheic keratoses are not
Although these growths are frequently confused with warts, moles, actinic keratoses, and melanoma skin cancer, they differ in a variety of ways.
- Warts are caused by a virus; seborrheic keratoses aren’t caused by a virus. Warts tend to develop more quickly, they don’t get as dark in color, and they don’t have that “pasted-on” appearance.
- Moles are skin-colored, or tan to brown in color. Almost everyone develops 20-30 moles during his or her lifetime-usually during childhood.
- Actinic keratoses, also called solar keratoses, are caused by the sun, and occur on body areas that have been exposed to the sunlight. The face, hands, forearms, and V of the neck are the most common areas for actinic keratoses. These growths are more common among pale-skinned, fair-haired, light-eyed individuals. They are flatter, redder, and rougher than seborrheic keratoses. Actinic keratoses are pre-cancerous, which means they may become skin cancers. Any raised, reddish, rough-textured growth should be examined by a dermatologist.
Melanoma is a serious form of skin cancer. Melanomas are often, but not always, dark brown to bluish-black growths. Melanomas may be confused with seborrheic keratoses because both can become very dark. It is wise to have any growth that turns dark, bleeds, itches, or becomes irritated checked by a dermatologist. Early detection of skin cancer is the best way to assure successful treatment.