Gliomas are tumors formed from glial cells. Glial cells in the brain hold nerve cells in place, bring food and oxygen to them, and help protect them from disease, such as infection.
The brain stem is the part of the brain connected to the spinal cord. It is in the lowest part of the brain, just above the back of the neck. The brain stem is the part of the brain that controls breathing, heart rate, and the nerves and muscles used in seeing, hearing, walking, talking, and eating. Most childhood brain stem gliomas are pontine gliomas, which form in a part of the brain stem called the pons.
|Anatomy of the brain, showing the cerebrum, cerebellum, brain stem, and other parts of the brain.||Anatomy of the inside of the brain, showing the pineal and pituitary glands, optic nerve, ventricles (with cerebrospinal fluid shown in blue), and other parts of the brain.|
This summary refers to the treatment of primary brain tumors (tumors that begin in the brain). Treatment for metastatic brain tumors, which are tumors formed by cancer cells that begin in other parts of the body and spread to the brain, is not discussed in this summary.
Brain tumors can occur in both children and adults; however, treatment for children may be different than treatment for adults. See the following PDQ treatment summaries for more information:
- Childhood Brain and Spinal Cord Tumors Treatment Overview
- Adult Brain Tumors Treatment
Brain tumors may be benign (not cancer) or malignant (cancer).
Benign brain tumors grow and press on nearby areas of the brain. They rarely spread into other tissues. Malignant brain tumors are likely to grow quickly and spread into other brain tissue. When a tumor grows into or presses on an area of the brain, it may stop that part of the brain from working the way it should. Both benign and malignant brain tumors can cause signs and symptoms and need treatment.
There are two types of brain stem gliomas in children.
Childhood brain stem glioma is either a diffuse intrinsic pontine glioma (DIPG) or focal or a low-grade glioma.
- DIPG is a high-grade tumor that is fast-growing and spreads all through the brain stem. It is hard to treat and has a poor prognosis (chance of recovery).
- A focal or low-grade glioma is slow-growing and is in one area of the brain stem. It is easier to treat than DIPG and has a better prognosis.
The cause of most childhood brain tumors is unknown.
Anything that increases your risk of getting a disease is called a risk factor. Having a risk factor does not mean that you will get cancer; not having risk factors doesn't mean that you will not get cancer. Talk with your child's doctor if you think your child may be at risk. Possible risk factors for brain stem glioma include:
- Having certain genetic disorders, such as neurofibromatosis type 1 (NF1).
The signs and symptoms of brain stem glioma are not the same in every child.
Signs and symptoms depend on the following:
- Where the tumor forms in the brain.
- The size of the tumor and whether it has spread all through the brain stem.
- How fast the tumor grows.
- The child's age and development.
Some tumors do not cause signs or symptoms. Signs and symptoms may be caused by childhood brain stem gliomas or by other conditions. Check with your child's doctor if your child has any of the following:
- Loss of ability to move one side of the face and/or body.
- Loss of balance and trouble walking.
- Vision and hearing problems.
- Morning headache or headache that goes away after vomiting.
- Nausea and vomiting.
- Unusual sleepiness.
- More or less energy than usual.
- Changes in behavior.
- Trouble learning in school.
Tests that examine the brain are used to detect (find) childhood brain stem glioma.
The following tests and procedures may be used:
- Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient's health habits and past illnesses and treatments will also be taken.
- Neurological exam: A series of questions and tests to check the brain, spinal cord, and nerve function. The exam checks a person's mental status, coordination, and ability to walk normally, and how well the muscles, senses, and reflexes work. This may also be called a neuro exam or a neurologic exam.
- MRI (magnetic resonance imaging) with gadolinium: A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the brain. A substance called gadolinium is injected into a vein. The gadolinium collects around the cancer cells so they show up brighter in the picture. This procedure is also called nuclear magnetic resonance imaging (NMRI).
A biopsy may be done to diagnose certain types of brain stem glioma.
If the MRI scan looks like the tumor is a DIPG, a biopsy is usually not done and the tumor is not removed.
If the MRI scan looks like a focal or low-grade brain stem glioma, a biopsy may be done. A part of the skull is removed and a needle is used to remove a sample of the brain tissue. Sometimes, the needle is guided by a computer. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are found, the doctor will remove as much tumor as safely possible during the same surgery.
Craniotomy: An opening is made in the skull and a piece of the skull is removed to show part of the brain.
The following test may be done on the tissue that was removed:
- Immunohistochemistry: A test that uses antibodies to check for certain antigens in a sample of tissue. The antibody is usually linked to a radioactive substance or a dye that causes the tissue to light up under a microscope. This type of test may be used to tell the difference between brain stem glioma and other brain tumors.
Certain factors affect prognosis (chance of recovery) and treatment options.
The prognosis and treatment options depend on:
- The type of brain stem glioma.
- Where the tumor is found in the brain and if it has spread within the brain stem.
- The age of the child when diagnosed.
- Whether or not the child has a condition called neurofibromatosis type 1.
- Whether the tumor has just been diagnosed or has recurred (come back).