Seborrheic Keratoses (SK)
What is Seborrheic Keratoses (SK)
Seborrheic Keratosis (SK) are raised growths on the skin. There may be just one or clusters of dozens. They usually start off light tan in color, and then may darken to dark brown or nearly black. They vary in size from a few millimeters to several centimeters.
These are not contagious and do not spread. They have NO relationship to skin cancer and DO NOT pose a risk to health. Unlike moles (nevi), they can never turn into melanoma. As people age they may simply develop more, and some people grow more than others. Sometimes seborrheic keratoses may erupt during pregnancy, following hormone replacement therapy, or as a result of other medical problems. They are often genetic and can be traced to other family members who have been affected. There is no direct correlation to sun exposure, and we often refer to them as “weeds”, as you will continue to develop more over time.
Characteristics of Seborrheic Keratoses (SK)
Characteristics of Seborrheic Keratoses
Stuck on – They are classically described as looking like someone took clay or a piece of dirt and “stuck” it on the skin. The edge of the SK is not usually attached to the underlying skin making it appear that it could be removed by picking it off with your fingernail. This is because SK arise from the epidermis, or top layer of the skin. They do not extend deep into the skin like warts.
Warty surface – SK may look like warts but they do not contain the human papilloma virus that causes warts. As they develop some can have a very rough surface with deep pits and fissures.
Smooth surface with horn pearls – Some SK do not have a rough surface. If they are smooth, they contain tiny bumps that look like seeds that are lighter or darker than the surrounding tissue. These are called horn pearls and they are actually bits of keratin that develop in a whirling, circular pattern.
Itching – For some reason, SK tend to itch especially the older we get. Some people will unintentionally manipulate or “pick at” a SK and cause it to be further irritated. If irritated enough, the skin around it can become red and the SK itself can bleed.
Seborrheic Keratoses Treatment
What can be done about Seborrheic Keratoses?
Although these lesions are completely benign, many find them to be irritating or cosmetically bothersome so they chose to have them removed. Some smaller lesions can be removed with liquid nitrogen, but most larger lesions are best removed with the Co2 Laser. The Co2 laser gives an excellent cosmetic result in people who desire removal of these lesions.
Dermatosis Papulosa Nigra
Dermatosis papulosa nigra (DPN) is characterized by the presence of multiple, small, 1-5 mm diameter, firm, black or dark brown papules on face and neck. They are a sub-type of benign seborrheic keratosis and occur among African Americans, Asians and Polynesians. There tends to a genetic correlation and they appear more in females than males. DPN’s usually start to appear in late adolescence and the number and size of lesions increase with age. They primarily occur on the cheeks and forehead, but can also be found on the neck, upper back and chest. The actor Morgan Freeman is well known for these lesions on his face. DPN’s do not cause any symptoms of pain or itching, but many consider them to be cosmetically unsightly. They have no cancerous potential, so removal is for cosmetic purposes only.
DPN’s can be removed effectively with the Ultrapulse Co2 laser. The lesions are frozen with a topical and/or injectable anesthetic and then the laser is used to systematically ablate the unwanted tissue. Because these lesions remain on the surface of the skin (similar to a “barnacle”) once treated with the laser, they can be gently sloughed off with a q-tip. Following removal, there will be small open areas that will need to heal over the next 7-10 days. During the healing process and for several months following, it is ESSENTIAL to use daily sun protection to avoid darkening of the treated area. Oftentimes these lesions often cover a large surface area, so we will choose a “zone” to focus on during each procedure. As these are a genetic condition, more lesions may develop over time and may require ongoing treatment.