Seborrheic keratosis is a common noncancerous (benign) skin growth. People tend to get more of them as they get older. Seborrheic keratoses are usually brown, black, or light tan. The growths (lesions) look waxy or scaly and slightly raised. Freezing a growth with liquid nitrogen (cryotherapy) can be an effective way to remove the seborrheic keratosis. It doesn't always work on raised, thicker growths. This method carries the risk of permanent loss of pigment, especially on Black or brown skin.