What Is a Mature Teratoma?

A mature teratoma, also called a dermoid cyst, is a growth that normally is present at birth and continues growing as the patient matures. The cyst is composed of bodily tissues such as teeth, skin, hair and fat. Mature teratomas are non-cancerous and usually are cured through surgical removal the cyst.

Some women develop mature teratomas on their ovaries. Although non-malignant, a mature teratoma can cause a variety of complications, such as infections and ruptured, rotated or twisted ovaries. Women between the ages of 20 and 40 are at the highest risk.

Mature teratomas can also form in the testes. Prepubertal teratomas form between the ages of 20 months and 4 years, and post-pubertal teratomas affect males between the ages of 20 and 40. Although most prepubertal cases involve a mature teratoma, this type of tumor is rare in adult males.

Some babies are born with sacrococcygeal teratomas, which are tumors that form near the backbone. Some tumors develop entirely on the outside of the body, and others are partially or completely internal. Sacrococcygeal teratomas can divert the blood flow from the fetus and might endanger the health of both the mother and the unborn baby.

Teratomas also can form in the mediastinum, which is the area between the lungs. Many mediastinal cysts do not produce symptoms. Doctors sometimes find them when treating unrelated illnesses or injuries.

A doctor who suspects that a patient has a mature teratoma might perform ultrasound tests to look inside the body. The doctor might perform X-rays to locate masses or use computed tomography (CT) or magnetic resonance imaging (MRI) tests to determine the cyst's density and boundaries. He or she might perform a needle biopsy to determine whether the cyst is malignant.

Doctors usually treat the condition by surgically removing the cyst. Sometimes the cysts are connected to other parts of the body, such as the lungs. If the doctor is unable to remove the entire tumor, he or she might remove part of it instead to provide the patient with relief from the symptoms. A mature teratoma usually does not grow back.

Medical practitioners treat testicular teratomas through a procedure called an orchiectomy, which removes the cyst along with the testicle. Women are treated either with a salpingo-oophorectomy, a procedure that removes the ovary, or with a cystectomy to remove only the cyst. Babies might undergo prenatal surgery if their health is at significant risk.