Dermoid cyst is a nonmalignant cyst formed from surface skin cells.
The cyst may contain elements of skin, hair, sweat glands, and bone, which form a small, hard swelling in the body. A dermoid cyst is caused by a fault in the folding of tissues during embryonic development or by a wound that forces surface skin cells under the skin. Dermoid cysts are often found in the ovary, but may occur elsewhere. The usual treatment is surgical removal of the cyst. See also CYST .