The tumors
may be malignant
(cancer) or benign
(not cancer). Most CNS embryonal tumors in children are malignant. Malignant brain tumors
are likely to grow quickly and spread into other parts of the brain. 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. Benign brain tumors grow and press on nearby areas of the brain. They rarely spread to other parts of the brain. Both benign and malignant brain tumors can cause signs
or symptoms
and need treatment.
Although cancer is rare in children, brain tumors are the third most common type of childhood cancer, after leukemia
and lymphoma.
This summary is about the treatment of primary
brain tumors (tumors that begin in the brain). The treatment of metastatic
brain tumors, which begin in other parts of the body and spread to the brain, is not discussed in this summary.
For information about the different types of brain and spinal cord tumors, see the PDQ
summary on Childhood Brain and Spinal Cord Tumors Treatment Overview.
Brain tumors occur in both children and adults. Treatment for adults may be different from treatment for children. See the PDQ summary on Adult Central Nervous System Tumors Treatment for more information on the treatment of adults.
There are different types of CNS embryonal tumors.
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.
The different types of CNS embryonal tumors include:
Medulloblastomas
Most CNS embryonal tumors are medulloblastomas. Medulloblastomas are fast-growing tumors that form in brain cells in the cerebellum. The cerebellum is at the lower back part of the brain between the cerebrum
and the brain stem. The cerebellum controls movement, balance, and posture. Medulloblastomas sometimes spread to the bone, bone marrow, lung, or other parts of the body, but this is rare.
CNS primitive neuroectodermal tumors
CNS primitive neuroectodermal tumors
(CNS PNETs) are fast-growing tumors that usually form in brain cells in the cerebrum. The cerebrum is at the top of the head and is the largest part of the brain. The cerebrum controls thinking, learning, problem-solving, emotions, speech, reading, writing, and voluntary movement. CNS PNETs may also form in the brain stem or spinal cord.
There are four types of CNS PNETs:
CNS neuroblastomas
CNS neuroblastomas
are a very rare type of neuroblastoma that form in the nervetissue
of the cerebrum or the layers of tissue that cover the brain and spinal cord. CNS neuroblastomas may be large and spread to other parts of the brain or spinal cord.
CNS ganglioneuroblastomas
CNS ganglioneuroblastomas are rare tumors that form in nerve tissue of the brain and spinal cord. They may form in one area and be fast growing or form in more than one area and be slow growing.
Medulloepitheliomas
Medulloepitheliomas are fast-growing tumors that form in brain cells that line tubelike spaces in the brain and spinal cord.
Ependymoblastomas
Ependymoblastomas are fast-growing tumors that form in brain cells lining the fluid
-filled spaces in the brain and spinal cord. They often form near the tailbone.
The pineal gland
is a tiny organ
in the center of the brain. The gland makes melatonin, a substance
that helps control our sleep cycle.
Pineoblastomas
form in cells of the pineal gland and are usually malignant. Pineoblastomas are fast-growing tumors with cells that look very different from normal pineal gland cells. Pineoblastomas are not a type of CNS embryonal tumor but treatment for them is a lot like treatment for CNS embryonal tumors.
Pineoblastoma is linked with inherited
changes in the retinoblastoma (RB1) gene. A child with the inherited form of retinoblastoma (cancer than forms in the tissues of the retina) has an increased risk of pineoblastoma. When retinoblastoma forms at the same time as a tumor in or near the pineal gland, it is called trilateral retinoblastoma. MRI
(magnetic resonance imaging) testing in children with retinoblastoma may detect pineoblastoma at an early stage when it can be treated successfully.
Certain genetic conditions increase the risk of childhood CNS embryonal tumors.
Anything that increases the 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.
Risk factors for CNS embryonal tumors include having the following inherited diseases:
In most cases, the cause of CNS embryonal tumors is not known.
Signs and symptoms of childhood CNS embryonal tumors or pineoblastomas depend on the child's age and where the tumor is.
These and other signs and symptoms may be caused by childhood CNS embryonal tumors, pineoblastomas, or other conditions. Check with your child's doctor if your child has any of the following:
Loss of balance, trouble walking, worsening handwriting, or slow speech.
Lack of coordination.
Headache, especially in the morning, or headache that goes away after vomiting.
General weakness or weakness on one side of the face.
Unusual sleepiness or change in energy level.
Infants and young children with these tumors may be irritable or grow slowly. Also they may not eat well or meet developmental milestones
such as sitting, walking, and talking in sentences.
Tests that examine the brain and spinal cord are used to detect (find) childhood CNS embryonal tumors or pineoblastomas.
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 patient'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) of the brain and spinal cord 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 and spinal cord. 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). Sometimes magnetic resonance spectroscopy
(MRS) is
done during the MRI scan to look at the chemicals in brain tissue.
Lumbar puncture: A procedure used to collect cerebrospinal fluid (CSF) from the spinal column. This is done by placing a needle between two bones in the spine
and into the CSF around the spinal cord and removing a sample of the fluid. The sample of CSF is checked under a microscope
for signs of tumor cells. The sample may also be checked for the amounts of protein
and glucose. A higher than normal amount of protein or lower than normal amount of glucose may be a sign of a tumor. This procedure is also called an LP or spinal tap.
Lumbar puncture. A patient lies in a curled position on a table. After a small area on the lower back is numbed, a spinal needle (a long, thin needle) is inserted into the lower part of the spinal column to remove cerebrospinal fluid (CSF, shown in blue). The fluid may be sent to a laboratory for testing.
A biopsy may be done to be sure of the diagnosis of CNS embryonal tumor or pineoblastoma.
If doctors think your child may have a CNS embryonal tumor or pineoblastoma, a biopsy
may be done. For brain tumors, the biopsy is done by removing part of the skull
and using a needle to remove a sample of tissue. Sometimes, a computer-guided needle is used to remove the tissue sample. A pathologist views the tissue under a microscope to look for cancer cells. If cancer cells are found, the doctor may remove as much tumor as safely possible during the same surgery. The piece of skull is usually put back in place after the procedure.
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 sample of tissue that is 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 different types of brain tumors.
Certain factors affect prognosis (chance of recovery) and treatment options.
