The central nervous system is made up of the brain and spinal cord. Central nervous system tumors are the second most common cancer in children Overview of Childhood Cancer In the United States, the overall incidence of cancer in children and adolescents has increased over time. From 1975 to 2022, rates increased by approximately 0.8 per 100,000 each year. However... read more under 15 years of age (after leukemia) and the leading cause of death in children from cancer.
The most common central nervous system tumors in children are (in order) astrocytomas Astrocytomas The central nervous system is made up of the brain and spinal cord. Astrocytomas are central nervous system tumors that develop from star-shaped cells (astrocytes) that help nerve cells in the... read more , medulloblastomas Medulloblastomas The central nervous system is made up of the brain and spinal cord. Medulloblastomas are rapidly growing brain tumors that develop in the cerebellum (the part of the brain that helps control... read more
, and ependymomas Ependymomas The central nervous system is made up of the brain and spinal cord. Ependymomas are slow-growing central nervous system tumors that develop from cells lining the spaces within the brain (ventricles)... read more 
.Brain tumors can cause various symptoms, including headaches, nausea, vomiting, vision problems, listlessness, and loss of coordination or balance.
The diagnosis is usually based on results of magnetic resonance imaging and a biopsy.
Treatment may involve surgery, radiation therapy, chemotherapy, or a combination.
The cause of central nervous system tumors is usually unknown. However, high doses of radiation Radiation and cancer Radiation injury is damage to tissues caused by exposure to ionizing radiation. Large doses of ionizing radiation can cause acute illness by reducing the production of blood cells and damaging... read more and certain genetic disorders (for example, neurofibromatosis Neurofibromatosis Neurofibromatosis is a group of genetic disorders in which many soft, fleshy growths of nerve tissue (neurofibromas) form under the skin and in other parts of the body, and flat spots that are... read more 
) are known to cause central nervous system tumors.
(See also brain tumors in adults Overview of Brain Tumors A brain tumor can be a noncancerous (benign) or cancerous (malignant) growth in the brain. It may originate in the brain or have spread (metastasized) to the brain from another part of the body... read more .)
Symptoms of Brain and Spinal Cord Tumors in Children
The first brain tumor symptoms may result from increased pressure within the skull (intracranial pressure). Pressure may be increased because the tumor blocks the flow of cerebrospinal fluid within the brain or because the tumor takes up space. Increased pressure can cause the following symptoms:
Headaches
Nausea and vomiting (often when the child first awakens)
Vision problems, such as double vision or vision loss
Difficulty turning the eyes upward
Changes in behavior or consciousness level, making the child irritable, listless, confused, or drowsy
Seizures
Other symptoms vary depending on where the tumor is located in the brain or the spine.
Diagnosis of Brain and Spinal Cord Tumors in Children
Imaging tests
Usually biopsy or sometimes surgery to remove the entire tumor
Sometimes a spinal tap
Doctors suspect a central nervous system tumor based on symptoms.
To check for a central nervous system tumor, doctors typically do an imaging test such as magnetic resonance imaging Magnetic Resonance Imaging (MRI) In magnetic resonance imaging (MRI), a strong magnetic field and very high frequency radio waves are used to produce highly detailed images. MRI does not use x-rays and is usually very safe... read more 
(MRI) of the brain, which can usually detect the tumor. Computed tomography Computed Tomography (CT) In computed tomography (CT), which used to be called computed axial tomography (CAT), an x-ray source and x-ray detector rotate around a person. In modern scanners, the x-ray detector usually... read more 
(CT) may also be done. Before MRI or CT is done, a contrast agent is usually injected into a vein (intravenously). Contrast agents are substances that make organs and other structures clearer to see on imaging tests.
If a central nervous system tumor is suspected, doctors usually remove a small piece of tissue (biopsy) to confirm the diagnosis. Sometimes, instead of removing a small piece, doctors surgically remove as much of the tumor as possible.
Sometimes a spinal tap (lumbar puncture How a Spinal Tap Is Done 
) is done to obtain cerebrospinal fluid for examination under a microscope. This procedure is done routinely to determine whether tumor cells have spread to the cerebrospinal fluid or when the diagnosis is unclear.
Treatment of Brain and Spinal Cord Tumors in Children
Surgical removal of the tumor
Chemotherapy, radiation therapy, or both
Drainage of cerebrospinal fluid
(See also Cancer Treatment Principles Cancer Treatment Principles Treating cancer is one of the most complex aspects of medical care. It involves a team that encompasses many types of doctors working together (for example, primary care doctors, gynecologists... read more .)
Usually, treatment of central nervous system tumors involves surgically removing the tumor Surgery for Cancer Surgery is a traditional form of cancer treatment. It is the most effective in eliminating most types of cancer before it has spread to lymph nodes or distant sites (metastasized). Surgery may... read more . Then, chemotherapy Chemotherapy and Other Systemic Cancer Treatments Systemic treatments are those that have effects throughout the body rather than being applied directly to the cancer. Chemotherapy is a form of systemic treatment that uses drugs to kill cancer... read more , radiation therapy Radiation Therapy for Cancer Radiation is a form of intense energy generated by a radioactive substance, such as cobalt, or by specialized equipment, such as an atomic particle (linear) accelerator. Radiation preferentially... read more , or both Combination Cancer Therapy Cancer drugs are most effective when given in combination. The rationale for combination therapy is to use drugs that work by different mechanisms, thereby decreasing the likelihood that resistant... read more are used. Treatment should be planned by a team of experts Care team for cancer treatment In the United States, the overall incidence of cancer in children and adolescents has increased over time. From 1975 to 2022, rates increased by approximately 0.8 per 100,000 each year. However... read more who have experience treating central nervous system tumors in children. The care team may include doctors who specialize in the care and treatment of babies, children, and adolescents such as pediatric cancer specialists (oncologists), pediatric neurologists, pediatric neurosurgeons, and radiation oncologists.
When possible, the tumor is removed surgically. Brain tumors are removed by opening the skull (called a craniotomy). Some brain tumors can be removed with little or no damage to the brain. After surgery, MRI is done to determine whether any of the tumor is left and, if so, how much.
If the tumor cannot be removed surgically, radiation therapy, chemotherapy, or both are usually required. In children younger than 5 years of age, depending on the tumor type, chemotherapy may be used first because radiation therapy can interfere with growth and brain development. If needed, radiation therapy may be used when children are older. Chemotherapy may also have serious side effects.
If the tumor is blocking the flow of cerebrospinal fluid, a small tube (catheter) may be used to drain the cerebrospinal fluid before the tumor is surgically removed. After a local or general anesthetic is used, the tube is inserted through a tiny opening drilled in the skull, and fluid is withdrawn to reduce the pressure within the skull. The tube is connected to a gauge that measures the pressure within the skull. After a few days, the tube is removed or may be converted to a permanent drain (shunt—see Hydrocephalus Hydrocephalus Hydrocephalus is an accumulation of extra fluid in the normal spaces within the brain (ventricles) and/or between the inner and middle layers of tissues that cover the brain (the subarachnoid... read more 
).
Because cancer is relatively rare in children, the doctor may speak with the parents about entry into a clinical trial, if available. In such trials, some children receive the standard treatment, and others receive the treatment being tested (called experimental treatment). The experimental treatment may involve new chemotherapy drugs, new combinations of older drugs, or new surgical or radiation techniques. However, experimental treatments are not always effective, and side effects or complications may not be known.
More Information
The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.
American Cancer Society: If Your Child Is Diagnosed With Cancer: A resource for parents and loved ones of a child who has cancer that provides information about how to cope with some of the problems and questions that come up just after a child is diagnosed
The brain tumors organizations here provide information about types of and treatments for brain tumors as well as information for caregivers about support resources:
