Seborrheic keratosis (SK) is a common non-cancerous (benign) skin growth that can occur in people as they age. These growths are often seen in middle-aged and older individuals, but they can develop at any age. They are most commonly found on areas of the skin that are frequently exposed to the sun, such as the face, neck, chest, and back, although they can appear anywhere on the body.
Key characteristics of seborrheic keratosis include:
- Appearance: Seborrheic keratoses can vary in color, but they are typically brown, tan, or black. They often have a waxy, scaly, or “pasted-on” appearance and can range in size from very small (a few millimeters) to larger than a centimeter.
- Texture: They may feel slightly elevated or have a rough texture when touched.
- Shape: Seborrheic keratoses can have various shapes, from round to oval, and they may be flat or slightly raised.
- Itching: While some SKs are asymptomatic, others may be itchy or irritated.
The exact cause of seborrheic keratosis is not fully understood, but they are believed to result from the overproduction of keratin, a protein that makes up the outer layer of the skin. Genetics may also play a role, as these growths tend to run in families.
Seborrheic keratoses are generally harmless however, If a seborrheic keratosis changes in color, shape, size, or becomes painful, it should be evaluated to rule out any potential skin cancers or other skin conditions. If treatment is necessary, options may include cryotherapy (freezing), electrosurgery, laser therapy, or simply shaving or scraping off the growth.
Regular skin checks and sun protection measures can help reduce the risk of seborrheic keratoses and other skin issues.