Seborrheic Keratosis
What is a seborrheic keratosis?
Seborrheic keratoses are common, benign skin growths. The term keratosis refers to an overgrowth of keratinocytes. The keratinocyte is the most common skin cell in the epidermis. They are usually brown, black, or light tan and have a texture of waxy or scaly raised lesions. Seborrheic keratoses can be referred to as epidermal tumors, but that doesn’t mean they are cancerous. It refers to having a cluster of extra cells on the outer layer of the skin. These growths are not harmful but, in some cases, seborrheic keratosis can be challenging to differentiate from melanoma, which is a severe type of skin cancer.
What do seborrheic keratoses look like?
As stated, seborrheic keratoses are usually brown or black and have a waxy texture. They may be described as looking “stuck on.” They are raised above the skin and can look scaly but feel flat when touched. On rare occasions, they can be pink, yellow, or white. Some seborrheic keratoses form in numbers, while others appear individually. They can look like tiny bubbles or cysts within the epidermis which can be visible with dermoscopy or higher magnification of the skin.
What causes seborrheic keratoses?
While doctors do not entirely understand what causes seborrheic keratoses to form, they do notice that this type of skin growth does run in families. Doctors suggest that it is inherited through genetics and typically develops later in life. Many notice that the peak time for developing seborrheic keratoses is around middle age.
- 30% of people have developed seborrheic keratosis by age 40
- About 75% have developed seborrheic keratosis by the age of 70
It is more common to develop if past family members have been affected as well. Researchers have noted that lighter-skinned people are more at risk of developing seborrheic keratosis. Still, those with a darker skin tone can develop what is called dermatosis papulosa nigra, which is a variant of seborrheic keratosis. Seborrheic keratoses are not contagious or infectious in nature.
Seborrheic keratoses are extremely common, affecting about 83 million people in the United States.
When to see a doctor?
The most common symptom of seborrheic keratosis is a round or oval-shaped waxy bump that grows gradually over time. Since seborrheic keratoses are harmless, they most often do not need treatment and are left alone. They may be removed if a patient is having discomfort due to the following reasons:
- It gets caught on clothes and jewelry
- Cosmetic preference
- Becoming irritated
While most seborrheic keratoses are non-cancerous, Dr. Chacon may want to remove the growth so that it can be evaluated under a microscope to ensure it is not cancerous. Surgical excision is performed under local anesthetic.
How is seborrheic keratoses removed?
The process of removing seborrheic keratoses can be done during an in-office visit. Treatment and removal methods include cryosurgery, electrocautery, scraping, or prescribing a hydrogen peroxide solution. Cryosurgery uses liquid nitrogen to freeze off the growth. Electrocautery uses an electrical current to scrape the growth. Scraping is performed with a curette, a scoop-like surgical instrument, and is commonly combined with electrosurgery. The hydrogen peroxide solution is available only by prescription and destroys the overproduced keratinocytes. It is important to emphasize that you should not try removing a seborrheic keratosis yourself. Doing this puts you at risk for infection or inflammation.