What Is a Seborrheic Keratosis?

A seborrheic keratosis is a noncancerous skin growth often seen on older adults, states Mayo Clinic. It is typically black, brown or tan, and it appears on the face, back, shoulders or chest. Multiple growths are typical, but one can sometimes appear by itself.

Seborrheic keratoses may itch, are oval or round shaped, are slightly elevated or flat, and range from very small to 2.5 centimeters in size, notes Mayo Clinic. A doctor should be seen if many growths appear over a short amount of time, sores that don’t heal appear or the growth bleed or become irritated. The cause of seborrheic keratoses is unknown but may be related to age and genetics. Doctors inspect growth and may remove the tissue to determine if it is cancerous.

Treatment for a seborrheic keratosis is typically unnecessary, but growths are often removed if irritation occurs, according to Mayo Clinic. Cryosurgery removes seborrheic keratoses, which involves freezing the growths with liquid nitrogen. This treatment is most effective with smaller growths and may alter the affected skin. Flat or thin seborrheic keratoses can also be removed by scraping the surface of the skin, and electrocautery may also be used along with scraping the skin to completely remove the growth. Electrocautery may cause scars and take longer than other methods. Laser treatments also remove seborrheic keratoses by vaporizing the growths.