Children's Hospital Colorado

Testicular Germ Cell Tumors (Seminoma and Non-seminoma)

What is a testicular germ cell tumor?

A testicular germ cell tumor is a form of testicular cancer. Germ cells in males are the cells that make sperm. More than 90% of testicular cancers start in the germ cells. There are two types of germ cells: seminomas and non-seminomas. Depending on which type of germ cell the cancer starts from, they form differently.

Seminomas and non-seminomas germ cell tumors (GCT)

Seminomas GCT tend to grow and spread more slowly than non-seminomas. Many testicular cancers contain both seminoma and non-seminoma cells. These mixed germ cell tumors are treated as non-seminomas because they grow and spread like non-seminomas.

What causes testicular germ cell tumors in children?

Doctors have not identified a clear cause for most cases of germ cell tumors in children. An increased risk of germ cell tumors has been associated with certain inherited diseases and genetic syndromes. These inherited diseases are also often associated with malformations of the central nervous system, genitourinary tract and lower spine.

Boys with cryptorchidism or undescended testicles also have an increased risk of developing testicular germ cell tumors. Cryptorchidism, however, can occur on its own and is also related to other genetic syndromes.

Who gets testicular germ cell tumors?

Testicular germ cell tumors are of course limited to boys. But germ cell tumors in general can occur in both boys and girls, although they are rare. Germ cell tumors account for about 2% to 4% of all cancers in children and adolescents younger than the age of 20.

What are the signs and symptoms of childhood testicular germ cell tumors?

Most testicular tumors are first noticed by the child himself, his parent or his physician as a growth developing on one of the testes. Testicular tumors are rare and many times, the growth is likely due to a much more common problem such as a hernia, hydrocele, testicular torsion or inflammation of the epididymis. Because a testicular growth can be linked to so many other conditions, it is important to consult your child’s doctor right away. Symptoms of a testicular tumor can include:

  • A swollen testicle
  • A hardened mass on one of the testicles
  • An abnormally shaped testicle
  • A difference in size between testicles
  • Pain originating from a testicle

What tests are used to diagnose testicular germ cell tumors?

To distinguish a testicular germ cell tumor from other common conditions, your son’s doctor will first start by looking at a complete medical history.

Next, using ultrasound imaging, your child’s doctor can decide whether or not the mass is a tumor or related to another condition. If the doctor finds that the growth is a tumor, they will need to conduct additional tests to decide how to treat it.

How do we make a diagnosis for a testicular germ cell tumor?

Your doctor will use a number of different tests before making a final diagnosis. Diagnostic tests may include:

  • Blood test - a sample of blood is taken to measure blood cell counts and look for other signs of cancer
  • Biopsy - a sample of tissue is removed from the tumor and examined under a microscope
  • Imaging tests – these can include an ultrasound, magnetic resonance imaging (MRI) or a computerized tomography (CT) scan, all of which can show different levels of detail of the growth

Why choose us for testicular germ cell tumor testing?

Everything we do at Children’s Hospital Colorado, we do with children in mind. This includes the range of tests we perform, from the smaller needles we use to match kid-sized veins for blood tests, to the variety of entertaining distraction methods we use when a child has to sit still for imaging. And if they need to be put to sleep for a procedure, our pediatric anesthesiologists are trained to work exclusively with kids, so we can make sure they get just the right dosage of anesthesia and don’t feel any pain during the procedure. All these things help to ensure that we get the test right the first time around and get the most accurate results we can.

How is a testicular germ cell tumor treated in children?

Your son’s doctor will determine the course of treatment based on his age, overall health and medical history, as well as the extent of the cancer and your child’s tolerance for specific medications, procedures and therapies.

Generally, the next steps in treatment depend on the results of the surgery and the staging imaging.

Treatment can include the following or a combination of the following:

  • Surgery (to remove the tumor and potentially the entire testicle)
  • Chemotherapy
  • Radiation
  • Supportive care (for the effects of treatment)
  • Hormonal replacement (if necessary)
  • Antibiotics (to prevent or treat infections)

Your son will need continuous follow-up care to determine his response to the treatment, test for any recurring conditions and manage the late effects of the treatment, if there are any.

Why choose us for treatment of testicular germ cell tumors?

At Children’s Colorado, urologic surgeons from the Surgical Oncology Program have extensive experience managing testicular germ cell tumors in children, adolescents and young adults. We are experienced with all phases of care for testicular tumors and have provided care for patients in all stages of this type of cancer.

By working with specialists in urology and oncology, we take a holistic approach to cancer treatment and the surgical removal of tumors. The co-director of our Surgical Oncology Program, Nicholas Cost, MD, is one of the few pediatric urologists in the U.S. who is fellowship-trained in urologic oncology, giving Children’s Colorado a unique edge in the treatment of pediatric cancer. Dr. Cost also serves on the Testicular Cancer Panel of the National Comprehensive Cancer Network. Our doctors are also active in clinical trials and research, always striving to find more effective, innovative ways to treat pediatric cancer.

Will removal of one testicle affect my son’s future fertility or hormone function?

Generally, no. Almost all patients who have a testicle removed will still have normal sperm and testosterone production if the other testicle appears normal on the preoperative imaging. However, we will discuss options of fertility preservation before surgery and consider following testosterone levels in follow-up appointments after the testicular cancer treatments.

Can my child have a testicular prosthesis if one of his testicles is removed for cancer?

Yes, once the patient has gone through puberty and we know the size of the normal, remaining testicle we can place a testicular prosthesis to match. That can be done at the same time as the removal of the testicular cancer or at a later date. It is a routine, outpatient surgery with very little postoperative recovery.

Is my son at risk for testicular cancer if one of his family members had testicular cancer?

Generally, the risk of developing testicular cancer is low, about 1 in 400 men will develop testicular cancer in their lifetime. While that risk may go up if they have a father or brother with testicular cancer, that risk is still only about 1 in 100 men. Therefore, we only recommend that they do regular testicular self-exams once they start to go through puberty. They should then notify their parents or doctor if anything is abnormal on that self-exam.

Helpful resources

  • CureSearch for Children’s Cancer is a nonprofit organization on a mission to end childhood cancer by driving targeted and innovative research with measurable results in an accelerated time frame. The website offers information about childhood cancers like germ cell tumors.
  • The Testicular Cancer Society is committed to raising awareness for the most common form of cancer in men ages 15 to 35, to provide education about the disease and give support for fighters, survivors and caregivers.
  • The Testicular Cancer Awareness Foundation is a nonprofit organization dedicated to the fight against testicular cancer through awareness and outreach.