What is a Glioma?
The most common type of brain tumor is a glioma. Gliomas begin from glial cells, which make up the supportive tissue of the brain. There are different types of glioma:
- Astrocytoma. This type of tumor forms from astrocytes, a type of glial cells. It is the most common brain tumor in children. It is grows most often in the cerebellum.
- Brain stem glioma. This tumor is found in the brain stem. Most brain stem tumors can’t be removed with surgery.
- Oligodendroglioma. This tumor grows in the cells that make the fatty covering of nerve cells called oligodendrocytes. It usually grows slowly. But it usually grows into brain tissue. This makes it very difficult to remove with surgery.
- Ependymoma. This usually grows in the lining of the ventricles that hold cerebrospinal fluid (CSF), or in the spinal cord. In children, they are usually near the cerebellum. They often block the flow of the CSF, the fluid that surrounds the brain and spinal cord. This may cause increased pressure in the skull.
- Optic nerve glioma. This kind of tumor is found in or around the nerves that send messages from the eyes to the brain. It often affects vision. It can also affect hormones since it’s usually at the base of the brain where hormone control is located.
How is a brain tumor diagnosed?
Your child's healthcare provider will ask about your child's health history and symptoms. He or she will examine your child. This will include a neurological exam. The exam tests reflexes, muscle strength, eye and mouth movement, and coordination. Your child's healthcare provider may refer your child to a cancer specialist (oncologist). Your child may have tests such as:
- CT scan. A CT scan uses a series of X-rays and a computer to make detailed pictures of the body.
- MRI. An MRI uses large magnets, radio waves, and a computer to make detailed pictures of the body. Contrast dye may be injected into your child's vein. It helps cancer cells be seen more clearly.
- Lumbar puncture. A special needle is placed into the lower back, into the spinal canal. This is the area around the spinal cord. This is done to check the brain and spinal cord for cancer cells. A small amount of cerebral spinal fluid (CSF) is removed and sent for testing. CSF is the fluid around the brain and spinal cord.
- Positron emission tomography (PET) scan. For this test, a radioactive sugar is injected into the bloodstream. Cancer cells use more sugar than normal cells, so the sugar will collect in cancer cells. A special camera is used to see where the radioactive sugar is in the body. A PET scan can sometimes spot cancer cells in different areas of the body, even when they can’t be seen by other tests. This test is often used in combination with a CT scan. This is called a PET/CT scan.
- Biopsy. Tumor cells are removed and sent to a lab for testing. This is done to determine the type of tumor and how quickly it is likely to grow.
- Blood tests. Blood tests may be done to check for substances that are released by some tumors. These are called tumor markers.
How is a brain tumor treated?
If your child has been diagnosed with a brain tumor and time allows, you may want your child to see a different oncologist (get a second opinion) before beginning treatment. In fact, your insurance company might require a second opinion.
Treatment may include one or more of the below:
- Surgery. Surgery is usually the first step in the treatment of brain tumors. The goal is to remove as much of the tumor as possible, while keeping brain function.
- Chemotherapy. These are medicines that kill cancer cells or stop them from growing. They may be given into the vein (IV), injected into tissue, or taken by mouth.
- Targeted therapy. These are medicines that kill cancer cells, but don’t harm healthy cells.
- Radiation therapy. These are high-energy X-rays or other types of radiation. They are used to kill cancer cells or stop them from growing.
- High-dose chemotherapy with a stem cell transplant. Young blood cells (stem cells) are taken from the child or from someone else. This is followed by a large amount of chemotherapy medicine. This causes damage to the bone marrow. After the chemotherapy, the stem cells are replaced.
Other treatments may include:
- Corticosteroids. These treat and prevent swelling in the brain.
- Antiseizure medicine. These treat and prevent seizures.
- Ventriculoperitoneal (VP) shunt. A long tube called a shunt may be placed to remove extra fluid from the inside the brain. This helps control the pressure.
- Supportive care. Treatment can cause side effects. Medicines and other treatments can be used for pain, fever, infection, and nausea and vomiting
- Antibiotics. These treat and prevent infections.
- Hormones. Medicines can replace hormones if a tumor affects natural hormone production.
With any cancer, how well a child is expected to recover (prognosis) varies. Keep in mind:
- Getting medical treatment right away is important for the best prognosis.
- Ongoing follow-up care during and after treatment is needed.
- New treatments are being tested to improve outcome and to lessen side effects.