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Causes, Risk Factors, and Prevention of Brain Tumors in Children
The exact cause of most brain and spinal cord tumors in children and teens is not known. Scientists have found some genetic and environmental risk factors, but most children with these tumors do not have any known risk factors. A risk factor is anything that raises a person’s chance of getting a disease such as cancer.
What causes brain tumors in children?
The cause of most brain and spinal cord tumors is not fully understood. Most children and teens with brain tumors have no known risk factors, so it’s important to know that there is nothing you or your child could have done to prevent these cancers.
Gene changes in brain tumors
Certain gene changes in normal brain cells can cause them to multiply out of control and become a tumor. For example, some genes control when our cells grow, divide into new cells, and die. Changes in these genes can lead to the development of cancer. Changes in several genes are usually needed before brain cells form tumors.
What causes gene changes?
Gene changes can either be inherited from a parent or acquired during a person’s life. Only a small number of people inherit DNA changes from a parent that increase their risk of cancer. Instead, most gene changes that raise the risk of a brain tumor in childhood are acquired mutations that occur early, sometimes before birth.
Researchers continue to search for answers about why brain tumors happen in children.
Risk factors for brain tumors
Inherited genetic syndromes, certain environmental factors such as radiation exposure, and having a weakened immune system can raise the risk of brain tumors. No links between childhood brain tumors and cell phone use, power lines, or exposure to chemicals or certain foods have been found.
Lifestyle-related risk factors for adult cancers, such as tobacco use, alcohol use, diet, exercise, and excess weight, are not known to play a major role in childhood cancers.
Genetic syndromes
Some inherited genetic syndromes increase the risk of developing several types of brain tumors:
Neurofibromatosis type 1 (NF1) is the most common syndrome linked to brain or spinal cord tumors. It is often inherited from a parent, but it can also start in children whose parents do not have it. Children with this syndrome may have low grade gliomas, such as optic gliomas, high grade gliomas, or tumors of the nerves like neurofibromas (benign tumors of peripheral nerves) or malignant peripheral nerve sheath tumors (MPNST). It is caused by changes in the NF1 tumor suppressor gene.
Neurofibromatosis type 2 is less common than type 1. It can either be inherited or start in children without a family history. It is associated with cranial or spinal nerve schwannomas, especially vestibular schwannomas (acoustic neuromas), which almost always occur on both sides of the head. It is also linked to an increased risk of meningiomas, as well as ependymomas. It is almost always caused by changes in the NF2 gene.
People with CMMRD have trouble repairing damaged DNA, which can lead to several types of cancer. Brain tumors are among the most common childhood tumors related to CMMRD, including medulloblastomas and high-grade gliomas. CMMRD also raises the risk of blood cancers and cancers of the gastrointestinal (GI) tract.
People with tuberous sclerosis may develop subependymal giant cell astrocytomas (SEGAs), as well as other benign tumors of the brain, skin, heart, kidneys, or other organs. This condition is caused by changes in either the TSC1 or the TSC2 genes, which normally act as tumor suppressors.
People with von Hippel-Lindau syndrome tend to develop blood vessel tumors (hemangioblastomas) of the cerebellum, spinal cord, or retina, as well as tumors in the kidney, pancreas, adrenal glands, and some other parts of the body. It is caused by changes in the VHL gene, which normally regulates how cells respond to low oxygen.
BCNS is caused by a gene change in the sonic hedgehog pathway (SHH) in a gene called PTCH1. About 5% of children with Gorlin syndrome will develop medulloblastoma, SHH type. People with BCNS are also at increased risk of developing skin cancers and meningiomas, especially after treatment with radiation.
People with Li-Fraumeni syndrome have an increased risk of gliomas and medulloblastoma, as well as breast cancer, soft tissue sarcomas, leukemia, and some other types of cancer. It is caused by changes in the TP53 gene.
Turcot syndrome is the presence of a brain tumor in someone with a hereditary colorectal cancer syndrome. It is most often associated with familial adenomatous polyposis (FAP) and Lynch syndrome (HNPCC). Brain tumors in Turcot syndrome can be medulloblastomas, glioblastomas, pituitary adenomas, ependymomas, or, in rare cases, astrocytomas.
Cowden syndrome is associated with gene changes in PTEN, which normally acts as a tumor suppressor gene. It has been associated with a higher risk of brain tumors such as cerebellar dysplastic gangliocytoma (also called Lhermitte-Duclos disease) and meningiomas.
People with hereditary retinoblastoma have a gene change in RB1, a tumor suppressor gene, throughout their body. This puts them at a higher risk of developing retinoblastoma, a cancer of the back part of the eye, as well as a type of brain tumor called pineoblastoma.
Rubinstein-Taybi syndrome is associated with an increased risk of medulloblastoma, oligodendrogliomas, and meningiomas. People with this condition have other features such as broad thumbs and big toes and distinctive facial features.
People with rhabdoid tumor predisposition syndrome have a gene change in SMARCB1 or SMARCA4, which raises the risk of developing a brain tumor called an atypical teratoid rhabdoid tumor (ATRT), along with other rhabdoid tumors of the kidney, schwannomas, meningiomas, malignant peripheral nerve sheath tumors, and other rare tumors.
People with DICER1 gene changes are more likely to have a rare tumor of the pineal gland called pineoblastoma. Other rare tumors, such as pleuropulmonary blastoma (a lung cancer of children), cystic nephroma of the kidney, and ovarian tumors, may be seen in families with gene changes in DICER1 as well. DICER1 normally works as a tumor suppressor gene, regulating how genes are expressed.
Radiation exposure
The only known environmental risk factor for brain tumors is radiation exposure, most often from radiation therapy given to the head to treat other cancers, such as leukemia or a previous brain tumor.
How long it might take a radiation-related tumor to develop depends on the type of tumor. For example, gliomas tend to occur earlier after treatment, while meningiomas often occur later.
Some people with genetic risk factors for brain tumors, such as Li-Fraumeni syndrome, hereditary retinoblastoma, or neurofibromatosis type 1, are much more sensitive to radiation. This can increase their risk of developing a radiation-related tumor.
Radiation-related tumors are rare. But because of the increased risk (as well as other possible side effects), radiation therapy is given to the head only after carefully weighing the possible benefits and risks. For most children and teens who need radiation therapy to the head to treat their cancer, the benefits far outweigh the increased risk of developing a brain tumor years later.
The possible risk from fetal or childhood exposure to imaging tests that use radiation, such as x-rays or CT scans, is not fully known. These tests use much lower levels of radiation than radiation therapy, so any increased risk is likely to be small. But to be safe, most doctors recommend that pregnant women and children not get these tests unless they are absolutely needed.
Having a weakened immune system
People with weakened immune systems have an increased risk of developing lymphomas of the brain or spinal cord (known as primary CNS lymphomas). Lymphomas are cancers of lymphocytes, a type of white blood cell that fights disease. Primary CNS lymphoma is less common than lymphoma that develops in other parts of the body.
A weakened immune system can be congenital (present at birth), or it can be caused by treatments for other cancers, treatment to prevent rejection of transplanted organs, or diseases such as AIDS (acquired immunodeficiency syndrome).
Factors with uncertain, controversial, or unproven effects on brain tumor risk
Other environmental factors such as exposure to vinyl chloride (a chemical used to manufacture plastics), petroleum products, and certain other chemicals have been linked with an increased risk of brain tumors in some studies but not in others.
Some research has suggested that trauma to the head might increase the risk of brain tumors. This is an ongoing area of research.
Exposure to aspartame (a sugar substitute), exposure to electromagnetic fields from power lines and transformers, and infection with certain viruses have been suggested as possible risk factors, but most researchers agree that there is no convincing evidence linking these factors to brain tumors. Research on these and other possible risk factors continues.
Do cell phones cause brain tumors?
Cell phones give off radiofrequency (RF) rays, which are a type of non-ionizing radiation. Unlike ionizing radiation (such as x-rays), RF energy does not damage DNA and is not known to cause cancer.
Still, because cell phones have internal antennae and are held close to the head, some people have worried that they might raise the risk of brain tumors.
Some studies have suggested a possible increased risk of brain tumors, such as vestibular schwannomas (acoustic neuromas), with cell phone use. However, most of the larger studies done so far have not found an increased risk, either overall or among specific types of tumors.
Research is still limited on long-term use (10 years or more), and cell phones haven’t been around long enough to determine the possible risks of lifetime use. Cell phone technology also continues to change, and it’s not clear how this might affect any risk.
These risks are being studied, but it will probably take many years to have clear answers. For people concerned about the possible risks, using the phone's speaker or a hands-free device may lower any risk.
For more on this topic, see Cellular Phones.
Can brain tumors in children be prevented?
Adults can lower their risk of certain cancers with lifestyle changes (such as staying at a healthy weight or quitting smoking), but at this time there are no known ways to prevent most cancers in children.
Other than exposure to radiation, there are no known lifestyle-related or environmental risk factors for brain and spinal cord tumors in younger people, and there is no way to protect against most of these cancers. If you or your child has a genetic risk factor for a brain tumor, early screening tests may be recommended to catch it early when it may be easier to treat.
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- References
Developed by the American Cancer Society medical and editorial content team with medical review and contribution by the American Society of Clinical Oncology (ASCO).
Dorsey JF, Salinas RD, Dang M, Alonso-Basanta M, Judy KD, Maity A, et al. Chapter 63A: Central Nervous System; Cancer of the Central Nervous System. In: Niederhuber JE, Armitage JO, Dorshow JH, Kastan MB, Tepper JE, eds. Abeloff’s Clinical Oncology. 6th ed. Philadelphia, Pa. Elsevier: 2019.
Hansford JR, Das A, McGee RB, et al. Update on Cancer Predisposition Syndromes and Surveillance Guidelines for Childhood Brain Tumors. Clin Cancer Res. 2024;30(11):2342-2350.
Huang A, Lindsay H, Tamrazi B, Adesina AM, Paulino AC, Pollack IF, et al. Chapter 22B: Tumors of the Central Nervous System: Embryonal and Pineal Region Tumors. In: Blaney SM, Adamson PC, Helman LJ, eds. Pizzo and Poplack’s Pediatric Oncology. 8th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2021.
Islam MP. Tuberous Sclerosis Complex. Semin Pediatr Neurol. 2021;37:100875.
Khattab A, Monga DK. Turcot Syndrome. [Updated 2023 Jun 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534782/
Michaud D, Batchelor T. Risk factors for brain tumors. UpToDate. 2025. Accessed at https://www.uptodate.com/contents/risk-factors-for-brain-tumors on August 28, 2025.
Parsons DW, Pollack IF, Hass-Hogan DA, Paulino AC, Kralik SF, Desai, NK, et al. Chapter 22A: Gliomas, Ependymomas, and Other Nonembryonal Tumors of the Central Nervous System. In: Blaney SM, Adamson PC, Helman LJ, eds. Pizzo and Poplack’s Pediatric Oncology. 8th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2021.
Patil P, Pencheva BB, Patil VM, Fangusaro J. Nervous system (NS) Tumors in Cancer Predisposition Syndromes. Neurotherapeutics. 2022;19(6):1752-1771.
Last Revised: February 9, 2026
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