Overview
Seborrheic keratosis (seb-o-REE-ik ker-uh-TOE-sis) is one of the most common noncancerous skin growths in older adults.
A seborrheic keratosis usually appears as a brown, black or light tan growth on the face, chest, shoulders or back. The growth has a waxy, scaly, slightly elevated appearance. Seborrheic keratoses don't become cancerous and aren't thought to be related to sun exposure, but they can look like skin cancer.
Seborrheic keratoses are normally painless and require no treatment. You may decide to have them removed if they become irritated by clothing or for cosmetic reasons.
Source: http://www.mayoclinic.com