(See also Overview of Skin Growths.)
Keloids are an extreme overgrowth of scar tissue. They may form in the months after an injury. They may be raised as much as ¼ inch (about 0.5 centimeters) or more above the surface of the skin. Keloids may result from any injury, including surgical incisions and acne. They are more common among darker-skinned people and typically develop on the mid chest, shoulders, upper back, and, sometimes, face and earlobes. Occasionally, they appear spontaneously.
Keloids are shiny, firm, smooth, and slightly pink or darkened. Keloids do not hurt, but they may itch or be sensitive to touch.
Keloids respond poorly to therapy, but monthly injections of corticosteroids may flatten them somewhat.
A doctor may try surgical or laser removal, but new, larger keloids often form in the scar resulting from the treatment. However, corticosteroid injections before and after surgery may reduce this risk.
Silicone patches or pressure garments applied to keloids may help prevent them from recurring. Recently, drugs that modify the actions of the immune system (immunomodulators), such as imiquimod, have been used to prevent keloids from developing or growing back.