Extragonadal Germ Cell Tumors

Extragonadal germ cell tumors form from developing sperm or egg cells that travel from the gonads to other parts of the body. “Extragonadal” means outside of the gonads, the sex organs. When cells that are meant to form sperm in the testicles or eggs in the ovaries travel to other parts of the body, they may grow into extragonadal germ cell tumors. These tumors may begin to grow anywhere in the body but usually begin in organs such as the pineal gland in the brain, in the mediastinum, or in the abdomen.

Extragonadal germ cell tumors can be benign or malignant. Benign extragonadal germ cell tumors are called benign teratomas. These are more common than malignant extragonadal germ cell tumors and often are very large.

Malignant extragonadal germ cell tumors are divided into two types, nonseminoma and seminoma. Nonseminomas tend to grow and spread more quickly than seminomas. They usually are large and cause signs and symptoms. If untreated, malignant extragonadal germ cell tumors may spread to the lungs, lymph nodes, bones, liver, or other parts of the body.

Age and gender can affect the risk of extragonadal germ cell tumors. Risk factors for malignant extragonadal germ cell tumors include being male, being age 20 or older, and having Klinefelter syndrome.

Extragonadal Germ Cell Tumors Treatment (PDQ®)

Source: National Cancer Institute