What Are Germ Cell Tumors?
Germ cell tumors are tissue masses formed by immature cells that usually become mature eggs or sperm. They can be benign (noncancerous) or malignant (cancerous).
- Although germ cell tumors are rare in children under age 15, they are the most common solid tumors in adolescents, accounting for 14 percent of all cancers among those 15-19 years old.
- Ninety percent of germ cell tumors are gonadal, which means they begin in the reproductive cells of the testes (testicular tumors) or ovaries (ovarian tumors).
- Germ cell tumors that appear in other parts of the body are called extragonadal germ cell tumors. They can occur in the abdomen, chest, neck, head, and brain. Learn more about germ cell tumors of the brain.
At Dana-Farber/Boston Children's Cancer and Blood Disorders Center, your child will receive care from top pediatric cancer doctors with deep specialized experience and expertise. Doctors in the Rare Tumors Program, within our Solid Tumor Center, care for children with germ cell tumors.
Causes and Symptoms of Childhood Germ Cell Tumors
As a parent, you undoubtedly want to know what may have caused your child's germ cell tumor. Doctors do not understand the cause of most germ cell tumors. Scientists know that they can be associated with several other inherited defects of the ovaries or testes. For example, patients with Klinefelter syndrome have an increased risk of developing extragonadal germ cell tumors.
It's critical to understand that germ cell tumors most often occur with no known cause. There's nothing that you could have done or avoided doing that would have prevented the tumor from developing.
Germ cell tumors can cause various symptoms in children based primarily on the tumor's size and location. They may include:
- A tumor, swelling or mass that can be seen or felt
- Constipation, incontinence, and leg weakness if the tumor is in the pelvis or abdomen
- Shortness of breath, if the tumor is in the chest
- Elevated levels of specific proteins secreted by the tumors into the blood, such alpha-fetoprotein (AFP) and beta-human chorionic gonadotrophin (B-HCG)
How We Diagnose and Classify Childhood Germ Cell Tumors
Effective treatment starts with an accurate diagnosis. Our radiologists can sometimes see germ cell tumors on a prenatal ultrasound. After birth, we typically diagnose them with a combination of imaging and biopsy.
After we complete all diagnostic testing, a team of pediatric tumor experts comes together to decide on the best treatment plan for your child. We meet with you and your family to discuss our treatment recommendations and answer any questions.
There are three main types of germ cell tumors:
- Teratomas (mature and immature)
- Seminomas
- Non-seminomas (including yolk sac tumors)
Teratomas have developed into cells that resemble other tissues in the body. These tumors are typically benign, but their growth can severely impinge on the vital organs around them. The treatment is usually surgical; sometimes chemotherapy is necessary as well.
Learn more about how we treat teratomas.
The other two types of tumors (seminoma and non-seminoma) are malignant. The difference between these two types is the degree of differentiation or maturation. Seminomas have not matured at all, whereas non-seminomas have matured to resemble fetal growth's early structures.
How We Treat Childhood Germ Cell Tumors
We use the full spectrum of available treatments for germ cell tumors, including advanced surgery and promising clinical trials.
Treatments we offer include:
- Surgery: Pediatric surgeons will biopsy the tumor and attempt to remove it.
- Chemotherapy: Chemotherapy is a drug that interferes with the cancer cell's ability to grow or reproduce. Chemotherapy before surgery may help shrink the tumor, making it possible to remove; used after surgery, it can help fight a cancer's recurrence. Different groups of chemotherapy drugs work in different ways to fight cancer cells and shrink tumors. Your child may receive chemotherapy:
- Orally, as a pill to swallow
- Intramuscularly, as an injection into the muscle or fat tissue
- Intravenously (IV) as a direct injection into the bloodstream
- Intrathecally, as a direct injection into the spinal column through a needle
- Radiation therapy: Our doctors use high-energy rays from a specialized machine to damage or destroy cancer cells and shrink tumors.
- Supportive care: Throughout your child's treatment, our doctors use supportive care to prevent and treat infections, minimize side effects of treatment, respond to complications, and keep your child comfortable.
Children with germ cell tumors receive ongoing care in our pediatric cancer survivorship programs. We provide everything from ongoing medical care to psychosocial and nutritional support. Our goal is to support your child's physical, mental, and emotional health as they grow.