Germ cell tumours of the brain

Germ cell tumours occur mostly in the area above the pituitary gland or in the pineal region of the brain. They start in germ cells found in the brain.

There are 2 main types:

Germinomas are more common. Germinomas can cause a small increase in human chorionic gonadotropin (HCG or b-HCG).

Non-germinatous germ cell tumours are less common. They are also known as non-germinomas. They are sometimes called mixed malignant germ cell tumours or secreting tumours because they can secrete substances (tumour markers) such as alpha-fetoprotein (AFP) and HCG.

Recurrent germ cell tumours are tumours that have come back after treatment.

Treatment of germ cell tumours of the brain depends on the type of germ cell tumour. Surgery is often used to obtain a biopsy for diagnosis. But most germ cell tumours are treated with radiation therapy or a combination of radiation therapy and chemotherapy instead of surgery. This is because germ cell tumours are often hard to reach with surgery.

Germinomas are very sensitive to chemotherapy and radiation therapy. Germinomas may be treated using the following:

• whole-ventricle radiation therapy
• radiation therapy to the brain and spine (craniospinal radiation)
• chemotherapy and radiation therapy to the tumour
• chemotherapy alone

Non-germinomas are sensitive to chemotherapy but less sensitive to radiation. Non-germinomas may be treated using the following:

• chemotherapy and craniospinal radiation
• chemotherapy and radiation therapy to the tumour
• chemotherapy alone

Radiation therapy is commonly used to treat germinomas. It may be the only type of therapy needed because these types of germ cell tumours are very sensitive to radiation and can often be cured with radiation therapy.

In children under 3 years old, radiation is delayed (if possible) to avoid long-term effects of radiation on developing brain cells. In these cases, chemotherapy will be given until the child reaches the age of 3. The type of radiation used is craniospinal radiation or whole-ventricle radiation with a boost to the primary tumour.

Chemotherapy is often combined with radiation therapy to treat germ cell tumours. This has proven to improve survival rates and allows doctors to give a lower dose of radiation. Chemotherapy could also be used to delay giving radiation therapy to children under 3 years old.

Chemotherapy drugs that may be used include:

• cyclophosphamide (Cytoxan, Procytox)
• ifosfamide (Ifex)
• etoposide (Vepesid, VP-16)
• cisplatin (Platinol AQ)
• carboplatin (Paraplatin, Paraplatin AQ)

Surgery is used to treat a type of germ cell tumour called a mature teratoma. Surgery is not usually used to treat any other types of germ cell tumours. If non-germinomas don’t respond to chemotherapy, surgery may be used.

Treatment for recurrent germ cell tumours will depend on previous treatment. Children who previously had chemotherapy are often treated with craniospinal radiation therapy. Recurrent germ cell tumours may also be treated with high-dose chemotherapy followed by stem cell transplant.

Many children with germ cell tumours are treated in a clinical trial. Clinical trials look at new ways to prevent, find and treat cancer. Find out more about clinical trials.