Germ cell tumors develop from cells that normally produce eggs or sperm in the reproductive organs — the testicles in men and ovaries in women. Germ, meaning "seed," refers to the role that germ cells play in producing egg and sperm cells. When abnormal growth and development occurs, these cells may produce a germ cell tumor. These relatively rare tumors can be cancerous or benign.
When the tumors occur in the ovary or testes, known as the gonad glands, they are called gonadal germ cell tumors. Most ovarian and testicular tumors in children originate from germ cells.
When germ cell tumors occur outside the reproductive organs, they are called extragonadal germ cell tumors. These usually occur because misplaced cells fail to migrate to their proper location in the body. Many researchers believe that extragonadal germ cell tumors are related to developmental problems that occur before birth.
Ninety percent of all germ cell tumors are gonadal. Most of the remaining 10 percent tend to occur in the chest, lower back and head.
Germ cell tumors represent about 3 percent of all childhood cancers. Researchers have not identified any toxic or environmental factors that increase the risk of this cancer. Among children, cure rates are generally good — above 90 percent — except for a few of the germ cell tumors.
The specific characteristics of each tumor will have a major impact on the treatment prescribed and the prognosis. There are several types of both benign and malignant germ cell tumors, including the following:
Symptoms for germ cell tumors vary widely, depending on the type of tumor and its location. The tumors below and their symptoms are listed by their location in the body.
Gonadal tumors are located in the reproductive organs — the ovaries in girls and the testicles in boys.
Your child's doctor will perform a thorough physical examination with special attention to the area that corresponds to your child's symptoms. Alfa-feto protein and human chorionic gonadotropin studies will be performed on your child's blood in addition to other blood studies. Various imaging studies, depending on the tumor's location, will also be required. These include:
Sometimes a diagnostic biopsy is needed before surgery is performed to remove the entire tumor.
Treatment depends on the location and type of the tumor and the extent of the disease. For some tumors, complete surgical removal is possible and effective, with close follow-up after surgery. Some germ cell tumors may be treated with radiation therapy alone or in combination with surgery. Chemotherapy is very effective for malignant germ cell tumors and is almost always used in combination with surgery.
With the exception of relatively few germ cell tumors in children, cure rates are 90 percent or higher.
Reviewed by health care specialists at UCSF Benioff Children's Hospital.