Seborrheic Keratosis

Medical Dermatology

Skin Conditions

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Seborrheic Keratoses are often confused with warts or moles. Seborrheic keratoses are common 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 tiny bump to larger than a half-dollar. A main feature of seborrheic keratoses is their waxy, "stuck-on" look.

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". These become more common and more numerous with time. Sometimes seborrheic keratoses may erupt during pregnancy, following estrogen therapy, or in association with other medical problems. 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. 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 as small, rough, itchy bumps. Eventually, they thicken and develop a rough, warty surface. 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 or jewelry. Because they may grow larger over the years, removal is sometimes recommended if they itch, get irritated, or bleed easily. Salves, ointments, and medication can neither cure nor prevent seborrheic keratoses. When treatment is required, seborrheic keratoses are treated by one of three methods. One method is called cryosurgery, or freezing. Cold liquid nitrogen is applied to the growth to freeze it. Blisters may form under the growth, which then dries into a scab like crust. The keratosis usually falls off within a few weeks. Occasionally, there may be a small dark or light spot after the treatment that will usually fade over time.

Another method is scraping them from the surface of the skin. An injection or spray is first used to numb the area before the growth is removed. No stitches are necessary, and bleeding is very limited. Electrosurgery is another form of treatment involving numbing the lesion, then burning it using an electric current.