Brain Tumors
What are brain and spinal cord tumors?
A tumor is a solid mass that forms when abnormal cells group together. Tumors happen when something goes wrong with the genes that manage cell growth, allowing cells to grow and divide out of control.
Tumors can form anywhere in the body, including the brain and spinal cord—the bundle of nerves and nerve fibers that sends and receives signals from the brain. The brain and spinal cord make up the central nervous system (CNS).
Some tumors don’t cause any symptoms. Others can kill or damage healthy cells, press on sensitive body tissue, or block the flow of blood, fluid, or signals to and from the brain.
There are treatments available to keep tumors from getting worse—especially when detected early.
Tumors don’t always mean cancer. They can either be:
- Benign (noncancerous): These tumors don’t spread to other parts of the body and may not require treatment if they’re not causing any serious problems. If they do need treatment, surgery is the most common kind.
- Malignant (cancerous): These tumors can invade surrounding tissue and spread (metastasize) to other parts of the body. Sometimes, surgery can remove malignant tumors entirely. But it can be hard to find the exact edges of malignant tumors, which can make it difficult for surgeons to take out the whole tumor. Surgery can’t completely remove tumors that have spread around the body.
CNS tumors are known as primary tumors if they first form in the brain or spinal cord. They’re called secondary (or metastatic) tumors if they break off from a tumor somewhere else in the body and travel to the brain or spinal cord. Secondary tumors are more common than primary CNS tumors and happen more often in adults than in children.
There are more than 120 types of brain and spinal cord tumors. Some of these tumors are only benign or malignant, but others may be both, depending on how much they’ve progressed. The National Cancer Institute (NCI) has more information on rare brain and spine tumors.
The following CNS tumors are grouped based on whether they are more likely to be benign or malignant:
Benign CNS tumors
Choroid plexus tumors
Meningioma
Meningiomas are tumors that develop from the thin membranes, or meninges, that cover the brain and spinal cord. They’re usually benign, grow slowly, and generally don’t invade surrounding normal tissue. Meningiomas rarely spread to other parts of the CNS or body. When tumors from other parts of the body spread to the meninges, this is known as meningeal carcinomatosis.
Pituitary tumors (also called pituitary adenomas)
Pituitary tumors are small and form in the pituitary gland, which manages many hormone levels within the body. Most pituitary tumors are benign, and they are more common as people age. Pituitary tumors are classified as either non-secreting or secreting. Secreting tumors release unusually high levels of pituitary hormones, which can trigger neurological conditions, including Cushing's syndrome—a harmful condition where the body makes too much of the hormone cortisol.
Vascular tumors
Vascular tumors are rare and usually benign. CNS vascular tumors form in the blood vessels of the brain and spinal cord. The most common kind of vascular tumors are hemangioblastomas. They’re cyst-like masses of tangled blood vessels that don’t usually spread.
Malignant CNS tumors
Glioma
Gliomas are the most common type of brain tumor. They grow from several types of glial cells, which support brain cell function. Astrocytomas are a type of glioma that forms in star-shaped glial cells called astrocytes. Other types of gliomas include:
- Midline gliomas: spread widely through the brainstem and midline structures of brain and are usually rare in adults
- Ependymomas: form in ependymal cells, a type of glial cell that lines the brain and spinal cord, and most often happen in young children
- Oligodendrogliomas: form in oligodendrocytes, a type of glial cell, and can cause seizures
- Optic gliomas: are found on or near the nerves that travel between the eye and brain vision centers and are common in people with neurofibromatosis
Not all gliomas progress at the same rate, and how much they affect the person varies. Prognosis for a glioma depends on how serious the tumor is, as well as factors like a person’s age and other medical history.
Embryonal tumors
Embryonal tumors may come from cells left over from the early development of the nervous system. They can spread throughout the brain and spinal cord in a scattered, patchy pattern. In rare cases, they can cause cancer outside the CNS. The two most common embryonal tumors are medulloblastomas and CNS neuroblastomas. Atypical teratoid/rhabdoid tumor (AT/RT) is another type of embryonal brain tumor that can spread to the spinal cord. It’s rare and usually grows rapidly, with symptoms usually getting worse very quickly.
Tumor symptoms
CNS tumors cause many different symptoms, which can make catching them difficult. Symptoms depend on location, size, growth rate, and tumor type.
Headaches are the most common brain tumor symptom, and back pain is a common early symptom of spinal cord tumors.
Damage to specific areas of the brain and spinal cord lead to specific symptoms. For example, a tumor in the motor area (which coordinates voluntary movement) may cause muscle weakness.
Brain tumor symptoms
A brain tumor can cause a variety of symptoms, including:
- Headaches which may gradually get worse over time
- Seizures (particularly if seizures start with no underlying cause during adulthood)
- Nausea and vomiting
- Vision or hearing problems
- Personality, behavior, and cognitive changes
- Psychotic episodes (such as hallucinations)
- Problems with speech, language, thinking, and memory
- Hormone or sleep problems
- Weakened sense of smell
Other possible brain tumor symptoms in adults are movement and balance problems, including:
- Weakness or fatigue
- Paralysis (such as facial paralysis and sagging eyelids)
- Trouble with swallowing
- Lack of coordination, dizziness, clumsiness, or trouble walking
- Gradual loss of sensation or movement in an arm or leg
- Loss of balance/equilibrium
In infants, the most obvious sign of a brain tumor is a rapidly widening head or swelling around the soft spot at the top of the head.
Spinal cord tumor symptoms
Common symptoms of a spinal cord tumor include:
- Sharp, burning, or tingling back pain that may be constant and severe and can spread to other parts of the body
- Numbness or loss of sensation, particularly in the arms or legs
- Movement problems and loss of muscle control
- Trouble walking
- Bowel or bladder control problems
Who is more likely to get brain and spinal cord tumors?
Anyone can develop a primary brain or spinal cord tumor, but the overall risk is very small. Among people who do develop CNS tumors, they’re most common in older adults.
Although brain tumors are uncommon in children, they tend to happen most often in children under age 9. Brain tumors are the leading cause of cancer deaths in children.
Researchers are still figuring out why CNS tumors develop, especially primary ones. Possible causes include:
- Viral infections
- Exposure to certain chemicals, radiation, or hazardous materials
- Immune system disorders
Some conditions that cause tumors tend to run in families—and gene mutations or genetic diseases can lead to primary CNS tumors. They can include:
- Neurofibromatosis
- Tuberous sclerosis
- von Hippel Lindau disease
Other risk factors for developing a primary CNS tumor include race (White men, for instance, are more likely to develop a CNS tumor) and occupation. Specifically, workers in jobs that require repeated contact with ionizing radiation or certain chemicals—including materials used in building supplies, plastics, textiles—have a greater chance of developing a brain tumor.
How are brain and spinal cord tumors diagnosed and treated?
Diagnosing brain and spinal cord tumors
To diagnose a CNS tumor, a doctor will review the person’s medical and family history and do physical and neurological exams. At some point, the doctor will likely refer a patient to a specialist—such as a neurologist, oncologist, or neuro-oncologist.
Getting specialized medical advice on brain and spinal cord tumors is important because diagnosing the type of brain or spinal cord tumor is often difficult. Some tumor types are rare and not well understood. It can help to get a second opinion from a comprehensive cancer center or neuro-oncologist with experience treating the specific tumor type.
To diagnose a brain or spinal cord tumor, a doctor may order diagnostic imaging procedures, which may include:
- MRI (magnetic resonance imaging)—the gold standard for diagnosing CNS tumors
- CT (computed tomography) scan
- Functional MRI (fMRI)
- Magnetic resonance spectroscopy (MRS)
- Positive emission tomography (PET)
- Single photon emission computed tomography (SPECT)
- Angiography
Laboratory and other tests can also help diagnose CNS tumors, including:
- Blood and urine tests
- EEG (electroencephalogram)
- CSF analysis—through a lumbar puncture or spinal tap
- Magnetoencephalography (MEG)
- Biopsy, where a doctor will remove a small tissue sample for a specialist to study
Find out more about neurological diagnostic tests and procedures.
Treating brain and spinal cord tumors
Malignant tumors require some form of treatment, while some small benign tumors may need only monitoring. Tumor treatment is different and unique for each person. A specialized team of doctors advises and assists people throughout brain and spinal cord tumor treatment. The treatment team may include a:
- Neurologist: a doctor who specializes in CNS disorders
- Neuro-oncologist: a neurologist or oncologist who specializes in CNS tumors
- Neuroradiologist: a doctor who specializes in the CNS and is trained in reading diagnostic imaging results
- Neurosurgical oncologist: a brain or spinal cord surgeon with specialized training in removing CNS tumors
- Oncologist: a doctor who specializes in cancer diagnosis and treatment
- Pathologist: a doctor who diagnoses diseases in tissues or cells using a variety of laboratory tests
- Neurosurgeon: a brain or spinal cord surgeon
- Radiation oncologist: a doctor who specializes in using radiation to treat cancer
The healthcare team will recommend a treatment plan based on the tumor’s location, type, size, and aggressiveness. They will also consider the person’s medical history, age, general health, and support system to select the best treatment plan.
Initial treatment for a CNS tumor may involve a variety of medicines to treat or ease symptoms, including:
- Anticonvulsants to treat or prevent seizures
- Pain medicines
- Steroids or other anti-inflammatory drugs to reduce swelling and improve blood flow
- Antidepressants to treat anxiety or depression that might happen after a tumor diagnosis
- Anti-nausea drugs
- Anti-inflammatory drugs to decrease swelling and/or associated pain
Medicines to treat tumors directly can include targeted therapy, which works on specific genes and proteins involved in tumor cell growth. Some examples of targeted therapies are inhibitors for BRAF and IDH mutations, which can cause malignant tumors.
Treatment for CNS tumors can also include a combination of any of the following treatments:
Neurosurgery
Neurosurgery (surgery on the CNS) is usually the first treatment doctors will consider to treat brain and spinal cord tumors. Sometimes, surgery can completely remove a tumor.
Some tumors are located deep within the brain, near vital structures (such as the brain stem), or don’t have well-defined edges. In these cases, surgery may be too risky, but a biopsy can help doctors understand a tumor and its needed treatment better.
During neurosurgery or biopsies, neurosurgeons will use different tools to reduce the risk of damage to the tissues surrounding the tumor. These include imaging to guide the surgeon during surgery and direct electrical stimulation of the brain to help the surgeon find the parts of the brain that control different things like movement or vision. Sometimes, patients may be awake during neurosurgery so surgeons can check their movement and speech during the procedure.
For malignant tumors, find more information on surgery to treat cancer.
Radiation therapy
Radiation therapy usually involves repeated doses of high-energy beams (such as X-rays or protons) to kill tumor cells or keep them from multiplying. The beams are focused to reduce damage to normal tissue. Radiation therapy can shrink tumors. It can also treat tumors that are too risky to treat in other ways or cannot be completely removed with surgery. The healthcare team will decide what type of radiation therapy works best to treat a tumor based on type, size, and location. Radiation treatment aims to reduce damage to surrounding healthy tissue, but it still causes side effects. They’re different from person to person and some symptoms are temporary. Side effects usually begin about two weeks after treatment starts. Radiation therapy in young children, especially if they’re 3 years and under, can cause problems with learning, processing information, thinking, and growing. There are late side effects of radiation that may happen months to years after treatment, including an increased risk of developing a secondary cancer. Sometimes, treatment causes shrinkage (atrophy) in the brain or spinal cord.
Chemotherapy
Chemotherapy uses powerful medicines to kill tumor cells or stop them from growing or spreading. Chemotherapy is given in cycles to more effectively damage and kill these cells and give normal cells time to recover from any damage. Chemotherapy can help shrink a tumor before the person gets another type of treatment—like surgery or radiation therapy. Chemotherapy can also help keep shrinking tumors after these other treatments.
Tumor treating fields
Tumor treating fields (TTF) are a type of cancer treatment that use low-energy electrical fields to stop cancer cells from growing and dividing. Doctors currently use TTF to treat glioblastomas.
Alternative and complementary therapies
Alternative and complementary therapies may help people with a tumor better cope with their diagnosis, treatment, or symptoms. Some of these therapies, however, may be harmful if people use them during or after standard treatments. The healthcare team can help patients safely plan for alternative and complementary therapies.
Common examples include:
- Nutritional and herbal supplements
- Vitamins
- Special diets
- Mind-body techniques to relax and reduce stress
What are the latest updates on brain and spinal cord tumors?
NINDS, a component of the National Institutes of Health (NIH), is the leading federal funder of research on the brain and nervous system, including research on brain and spinal cord tumors. NINDS supports new and innovative research to better understand, diagnose, and treat CNS tumors. NINDS-supported research projects cover a wide range of topics on these tumors. NIH supports much of its CNS tumor research through the collaborative efforts of NINDS and the National Cancer Institute (NCI).
Several of today’s CNS treatments were experimental therapies only a decade ago. Scientists continue to investigate ways to better understand, diagnose, and treat CNS tumors. Their research that looks at genetic risk factors, environmental causes, and molecular mechanisms of tumors could lead to breakthrough treatments.
Jointly, the Surgical Neurology Branch of NINDS and the NCI Neuro-Oncology Branch coordinate clinical care and research to develop and test the effectiveness/safety of new therapies for people with CNS tumors. These experimental treatment options may include new medicines, combination therapy, gene therapy, advanced imaging and artificial intelligence, biologic “immuno-agents”, surgery, and radiation.
The immune system attacks foreign substances in the body, but because the body doesn’t always identify cancer cells as foreign, in many different brain tumors they don’t cause much of an immune response. Researchers are testing different biological therapies and immunotherapies to provoke a strong immune response to tumor cells, including:
- Proteins (such as interleukin and interferon) and other substances that slow tumor growth
- Antibodies (proteins that are normally produced by the body to fight bacteria and viruses) use certain medicines to seek out tumor cells and deliver toxins to it
- Gene therapy uses a virus that can pass through the brain’s protective blood-brain barrier to deliver a gene that kills the tumor cell
- Vaccine therapy, which strengthens the immune response and causes the body to attack the tumor
- Different methods for delivering treatments into tumor cells are being explored because they have fewer risks of triggering immune responses or causing damage to other cells compared to traditional methods. These methods include what are called nonviral vectors (for example, liposomes, nanoparticles, or polymeric vectors).
- Cell-based therapeutics are another promising treatment for brain tumors. Specifically, “off-the-shelf” engineered stem cells offer a possible path for addressing remaining glioblastoma multiforme after surgery. A type of treatment called chimeric antigen receptor (CAR) T cell therapies is an emerging treatment option for diffuse midline glioma (DMG), a fatal cancer of the CNS in children and adolescents.
- Focused ultrasound (FUS) is a new technology that may be able to deliver treatments directly to the brain more efficiently than traditional methods.
Researchers are exploring new targeted therapy and drug delivery approaches. NCI and NINDS are funding research to understand which types of cancer cells in the brain are more likely to aggressively invade surrounding healthy tissue. The Food and Drug Administration has approved targeted therapies for BRAF and IDH mutations, which can cause malignant tumor growth. Researchers are continuing to advance these treatments.
Scientists are testing different therapies to target cells that turn cancerous, including:
- Compounds that block blood vessel growth and the flow of nutrients and oxygen to the tumor
- Diagnostic and therapeutic screening tools for oncogenes—transformed genes that are involved in cell growth and cause normal cells to divide uncontrollably and become malignant
- Kinase inhibitors—proteins that block growth-signaling enzymes without harming normal cells—may make CNS tumors more sensitive to chemotherapy
Biomarkers are molecules or other substances in the blood or tissue that can be used to diagnose or monitor a disorder. Identifying CNS tumor biomarkers can help scientists understand the risk of developing tumors from environmental toxins and other causes. This research may also lead to the development of new treatments. NIH scientists have found some CNS tumor biomarkers, such as the epithelial growth factor receptor (EGFR) gene, and have identified glial fibrillary acid protein (GFAP) as another possible biomarker. Identifying biomarkers may lead to better diagnosis, monitoring, and treatment of tumors.
Researchers are finding new ways to combine treatments—like radiation therapy and chemotherapy—with other therapies. This can possibly make these treatments less toxic and more effective.
Surgery research helps scientists understand how to combine surgery with other treatments and improve the quality of life and survival after surgery on CNS tumors. NINDS-supported researchers are testing out ways to improve the surgery process—such as using fluorescence and other new imaging techniques to guide surgeons in removing tumors.
How can I or my loved one help improve care for people with brain or spinal cord tumors?
Clinical trials increase our understanding of CNS tumors with the goal of improving how doctors treat them. Consider participating in a clinical trial so clinicians and scientists can learn more about brain and spinal tumors. Clinical research with human participants helps researchers learn more about a disorder and perhaps find better ways to detect, treat, or prevent disease safely.
All types of participants are needed—those who are healthy or may have an illness or disease—of all different ages, sexes, races, and ethnicities. This helps make sure that study results apply to as many people as possible, and that treatments will be safe and effective for everyone who will use them.
For information about participating in clinical research, visit NIH Clinical Research Trials and You. Learn about clinical trials currently looking for people with CNS tumors at Clinicaltrials.gov, a searchable database of current and past clinical studies and research results.