Seborrheic Keratosis Vs Melanoma, Seborrheic keratosis (SK) is a very common benign skin tumor (or growth) which is often mistaken for an abnormal or cancerous mole. The tendency to have these growths is inherited and a family history of large numbers of these growths suggests a significant risk for others in the family to develop these growths. Those who inherit a very strong tendency for SKs may begin developing hundreds of the growths at an early age, usually in their early thirties.
The appearance of SKs can vary considerably, making it difficult for patients to determine on their own whether these are worrisome or not. They may range in color from white to flesh-colored to tan to brown, or even black. They usually have an appearance described as “stuck on” as they often look like they could be easily scratched off the skin. Some may appear warty and others may be smooth. The borders of SKs are usually irregular and uneven, and they may have bumps of various heights in the lesion. They may develop on any part of the skin except the palms and soles, are not related to sun exposure, and may stay small or grow larger and there is no known way to prevent their appearance.
Diagnosis: The diagnosis of seborrheic keratoses is usually made by a physician on the basis of its appearance. In cases where the appearance of the growth is not perfectly typical for SK a family physician may refer a patient to a dermatologist. If the dermatologist is unable to diagnose the growth by its appearance it may be necessary to perform a biopsy to rule out more worrisome growths, such as skin cancers. Patients who have many SKs should not assume that a growth which is not absolutely the same as the others is benign, but should have it checked by a physician.
Symptoms: As previously mentioned, SKs do not develop into skin cancers, but they do occasionally itch. Most of the time, only a few of these lesions will itch and they can be removed by freezing them with liquid nitrogen, which causes the SK to dry up and fall off and then resolves the itching. The itching in an SK may cause the patient to scratch it and change the appearance, making it more difficult to diagnose without a biopsy. Another risk with scratching is the development of a skin infection in the scratched area. Seborrheic keratoses on the scalp may, if they are thick, be caught on combs and styling appliances and become sore or by torn off. It is not uncommon for an occasional SK to dry up and become crumbly until it finally falls off. Because the part of the lesion which falls off is only a thick layer of dead skin on the surface the growth may return over time.
Treatment: Seborrheic keratoses are usually treated by liquid nitrogen cryotherapy (“freezing”). Unless the SK is itching, painful, or bleeding this is considered a cosmetic procedure and insurance will not cover it. Most insurance policies cover the removal of symptomatic SKs. Other methods of removal include shave excision (numbing the lesion and then cutting it off flat with the skin) or laser treatment. The removal technique has no effect on whether the procedure will be covered by insurance.