Noncancerous, Precancerous and Cancerous Tumors

Moles are pigmented skin growths that are may be brown, black, or bluish. Moles may appear singly or in groups anywhere on the skin. Moles often appear on the skin in childhood and before the age of 20. Sometimes moles appear later in life. In adulthood, it's common for the average adult to have 10 to 40 moles.

Moles may change in appearance over time. They may become raised or experience a slight change in color. Hair may grow out of moles. Sometimes, moles do not change or they may disappear.