A type of germ cell tumor that may contain several types of body tissue.

Teratomas are growths of cells, called tumors, that contain several types of body tissue. They may include hair, muscle and bone. They occur most often in the ovaries and the testicles. They may be cancerous or noncancerous.

Symptoms can depend on the location. A lump or swelling may be seen or felt. Some babies have a mass that can be seen on an ultrasound before birth.

Treatment may involve surgery, radiation or chemotherapy.