Brainstem Tumor: Symptoms, Causes, and Treatment
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick answer
A brainstem tumor is an abnormal growth in the midbrain, pons or medulla, most often a glioma. Symptoms include balance problems, double vision, slurred speech, trouble swallowing, one-sided weakness and headaches with morning nausea or vomiting. Treatment may include surgery when safely reachable, radiation, chemotherapy, targeted therapy and supportive care, and outlook depends on how the tumor grows. [1] [2]
What the research says
According to PubMed:
Shorter radiotherapy courses performed about as well as standard ones. A systematic review and meta-analysis of five studies (518 patients) with diffuse intrinsic pontine glioma found no significant difference between hypofractionated and conventional radiotherapy in one-year overall survival (29% vs 22%) or median overall survival (9.7 vs 9.3 months). (Viani et al., DOI).
Early CAR T-cell results are encouraging but very small. In the first four patients with H3K27M-mutated DIPG or spinal cord diffuse midline glioma treated with GD2-CAR T cells in a phase I trial, three showed clinical and radiographic improvement; toxicity was largely related to tumor location and reversible with intensive supportive care. (Majzner et al., DOI).
The outlook for pediatric pontine disease remains serious. A 2026 review put median overall survival at about 11 months, described radiotherapy as the only modality with reproducible but transient benefit, and noted that the population behind dordaviprone's accelerated approval excluded DIPG. (Wei et al., DOI).
Study details are from PubMed abstracts.
What Is a Brainstem Tumor?
A brainstem tumor is a growth that forms in the midbrain, pons, or medulla — the three areas at the base of the brain that connect it to the spinal cord. This region guides many of the body's most essential functions, including movement, balance, coordination, sensation, speech, swallowing, and breathing.
The majority of brainstem tumors are gliomas, which begin in glial cells — the cells that support and nourish nerve cells. These include diffuse midline glioma (DMG), which is especially common and often aggressive in children, and low-grade gliomas, which grow more slowly. Some tumors can be noncancerous (benign) and others cancerous (malignant), and a single tumor or multiple growths can form [1].
The location matters as much as the tumor type. The brainstem is small and densely packed with nerve pathways, so even a small growth can cause significant problems. Tumors sit close to the nerves that control movement, breathing, and swallowing, which makes many of them difficult to remove surgically [1].
Who Gets Brainstem Tumors?
Brainstem tumors are more common in children than in adults, and gliomas that start in the pons occur most often in childhood. Adults develop a broader mix of gliomas and other tumor types, such as ependymomas and hemangioblastomas. Some tumors grow slowly and stay in one area for a long time, while others spread widely through brainstem tissue [1].
What are the symptoms of a brainstem tumor?
Because the brainstem is compact and carries so many message routes, people often notice several symptoms at once. Symptoms can build gradually over time or appear quickly. They typically involve movement, vision, speech, or the functions the brainstem controls.
Symptom group | What you might notice |
Balance and coordination | Trouble walking or standing, clumsiness, dropping items, difficulty with fine motor tasks, dizziness or unsteadiness |
Eye movement | Double vision, trouble moving the eyes in one or more directions, eyes that drift or do not line up |
Speech and swallowing | Slurred or slowed speech, difficulty swallowing food or liquids, coughing or choking during meals |
One-sided weakness | Dragging a foot, trouble climbing stairs, weakness in an arm, leg, or side of the face |
Face and hearing | Facial drooping or uneven expression, ringing in one ear, reduced hearing |
Headaches and nausea | Headaches that are worse when waking or lying down, nausea or vomiting in the morning — often from blocked fluid flow and pressure inside the skull |
Behavior and school changes (children) | Irritability or mood changes, trouble focusing, changes in daily routine or activity |
Breathing changes | Slowed or irregular breathing rhythm as a tumor presses on the medulla |
When to See a Doctor
See a doctor for any new symptom that affects movement, balance, eye motion, speech, swallowing, or strength. Seek care right away if you or your child develops sudden trouble walking or loss of balance, new double vision or drifting eyes, slurred speech or trouble swallowing, weakness in the face, arm, or leg, ongoing headaches (especially in the morning), morning nausea or vomiting, changes in breathing rhythm, or a sudden change in behavior or school performance [1].
Do not wait out mild changes. Symptoms that keep worsening over days or weeks — or any new symptom that appears — deserve prompt evaluation, because the brainstem is small and controls many important body functions [1].
What causes brainstem tumors and who is at risk?
The exact cause of most brainstem tumors is unknown. A tumor forms when certain cells in the midbrain, pons, or medulla begin to grow in an uncontrolled way. This usually happens because of gene changes that affect how glial cells grow and divide — changes that occur on their own during cell development. They are not usually linked to anything a person did or was exposed to [1].
There is no evidence that diet, stress, or environmental exposures cause brainstem tumors, and very few risk factors are known.
Risk factor | What the evidence shows |
Age | More common in children than adults; pons gliomas occur most often in children, while adults have a wider mix of tumor types |
Prior high-dose radiation | Earlier high-dose radiation treatment for other tumors or cancers is one of the best-known risk factors |
Rare genetic conditions | Neurofibromatosis type 1 (NF-1) raises the chance of certain brainstem tumors, including pilocytic astrocytomas, though tumors remain uncommon even with the condition |
Lifestyle and environment | No link found with diet, lifestyle habits, or environmental exposures |
What types of brainstem tumors are there?
Diffuse midline glioma (DMG) is the most common brainstem tumor in children and the most malignant. It was historically called diffuse intrinsic pontine glioma (DIPG). DMG tumors are high-grade, grow quickly, usually begin in the pons, and spread between cells without clear borders — which makes surgical removal difficult [1].
Low-grade gliomas grow more slowly and may stay in one place. Some grow outward from the surface of the brainstem — called exophytic tumors — and can be easier to reach with surgery. This group includes pilocytic astrocytoma (slow-growing, and able to form in the midbrain, pons, or medulla), pilomyxoid astrocytoma (a less common, often more aggressive variant), and ganglioglioma (a rare tumor containing both nerve and glial cells, sometimes found in the lower brainstem) [1].
Researchers also describe rarer types tied to specific gene changes, such as angiocentric gliomas linked to MYB gene changes, and PLNTYs (polymorphous low-grade neuroepithelial tumors of the young) linked to MAPK pathway genes. Childhood-type diffuse low-grade gliomas often carry MAPK pathway gene changes, while adult-type diffuse low-grade gliomas more often carry IDH gene changes [1].
What complications can a brainstem tumor cause?
Complications reflect the long-term effects a brainstem tumor can have on movement, breathing, and other functions, and they vary from person to person.
Complication | How it develops |
Hydrocephalus | The tumor blocks the flow of cerebrospinal fluid, so fluid builds up on the brain and raises pressure inside the skull; pressure relief treatment may be needed |
Breathing problems | Tumors in or near the medulla can slow or make breathing rhythm irregular over time |
Long-term swallowing difficulty | Ongoing pressure on the nerves that control throat and tongue movement makes swallowing unsafe and raises choking or aspiration risk |
Lasting weakness or poor coordination | Continued nerve pressure causes lasting problems with strength, balance, or fine motor skills |
Vision and eye movement problems | Tumors involving cranial nerves cause lasting changes in eye control or vision |
Learning and behavior changes in children | Growing tumors can bring ongoing challenges with attention, thinking speed, and school performance |
How are brainstem tumors diagnosed?
Diagnosis starts with a review of symptoms and a physical and neurological exam. Testing balance, eye motion, strength, coordination, and swallowing shows which parts of the brainstem may be affected. Imaging usually follows, and sometimes a tissue or spinal fluid sample is needed [2].
Test | What it shows |
MRI with and without contrast | The main diagnostic test; detailed pictures that show the tumor's presence and location, its effect on nearby structures, whether it stays in one area or spreads, and features that identify common types including diffuse midline glioma |
Other imaging | CT scans and specialized MRI techniques help confirm the tumor's position and rule out other conditions that can look similar, such as inflammation, cavernous malformations, or demyelinating disease like multiple sclerosis |
Needle biopsy | A small tissue sample; modern techniques offer high accuracy with a low chance of lasting side effects, and are most helpful when MRI is unclear or several tumor types are possible |
Lumbar puncture (spinal tap) | Spinal fluid is checked for tumor cells or genetic changes that point to a specific tumor type, helping confirm the diagnosis and guide treatment |
The tumor's location, growth pattern, and cell features are combined to identify the tumor type — the key first step in planning care [2].
What are the treatment options for a brainstem tumor?
Treatment depends on the tumor's type, size, and location. Several approaches are often used together, and supportive care runs alongside them.
Treatment | When it is used |
Surgery | When the tumor is safely reachable — more common with tumors that grow in one area, such as some low-grade gliomas. Tumors that reach open fluid-filled spaces around the brainstem can sometimes be easier to remove. Many cannot be fully removed because they sit near areas controlling movement, breathing, and swallowing; surgery may remove part of the tumor or relieve pressure |
Biopsy | Confirms the tumor type and reveals gene changes that guide treatment choices; newer methods are safe with a low chance of lasting problems |
Radiation therapy | Focused energy beams slow or stop growth; often used for diffuse midline glioma and tumors that cannot be removed, and may ease pressure symptoms. Carries a risk of delayed injury — damage that appears months or years after treatment |
Chemotherapy | Medicines for fast-growing tumors or tumors that come back; the specific drugs vary with tumor type and growth speed |
Targeted therapy | Medicines that block growth signals for tumors with specific gene changes, such as certain BRAF changes. Dordaviprone received FDA accelerated approval in 2025 only for diffuse midline glioma with an H3 K27M mutation that has progressed after earlier treatment, and research continues for children and adults with brainstem gliomas |
Immunotherapy remains an active research area. CAR-T cell therapy targeting the GD2 protein has been studied for diffuse midline glioma, and early studies in children and young adults show promising responses in some cases [2].
Supportive care focuses on easing symptoms caused by pressure on nerve pathways, including support for swallowing, breathing, movement, and fluid balance when needed [2].
Clinical Trials and Emerging Treatments
Because many brainstem tumors — especially diffuse midline glioma — are difficult to treat with current options, clinical trials play an important role. Researchers are testing treatments aimed at specific gene changes in low-grade gliomas and DMG, medicines that block internal growth signals (early research suggests they may slow some low-grade gliomas, though more studies are needed for brainstem tumors), and new ways to deliver medicine directly to the brainstem to reach the tumor while limiting effects on function areas. Trials are also exploring new imaging tools, biopsy methods, and supportive treatments [2].
What is the prognosis for a brainstem tumor?
The outlook depends greatly on the tumor's type, location, and growth pattern. Some tumors grow slowly and may stay in one area for a long time; others grow quickly and are harder to control because they spread through brainstem tissue. Life expectancy varies based on these factors, and there is no single cure for all brainstem tumors [2].
Fast-growing tumors such as diffuse midline glioma tend to spread through the pons and surrounding areas, which limits the options for removing or slowing the growth and can lead to a shorter survival. Slow-growing low-grade gliomas — including pilocytic astrocytoma, pilomyxoid astrocytoma, fibrillary astrocytoma, and ganglioglioma — may stay in one spot and can sometimes be managed for long periods with treatment or observation [2].
The tumor's size and position within the midbrain, pons, or medulla also affect the outlook because these areas guide important body functions, and age plays a role — children are more likely to have tumors that begin in the pons, while adults have a wider mix of positions. Prognosis is different for each person, and understanding the tumor type and how it grows is the first step in planning care [2].
How should you prepare for a brainstem tumor appointment?
If you have symptoms that worry you, make an appointment with a doctor. You will likely be referred to specialists, including neurologists (brain condition specialists), medical oncologists (medicine-based cancer treatment), radiation oncologists, neuro-oncologists (nervous system cancer specialists), neurosurgeons, and rehabilitation specialists [2].
Before the visit, write down your symptoms and how long you have had them, list all medical conditions and medicines (prescription and over-the-counter, with doses), ask whether any preparation is needed in advance, and bring a family member or friend to help remember the information shared. Bring a written list of questions, such as what may be causing the symptoms, what tests are needed and whether they require preparation, whether a specialist visit is appropriate, and — after diagnosis — where the tumor is located, how large it is, how it is likely to grow, what the treatment goals are, whether surgery or radiation is an option and what the risks are, whether chemotherapy will be needed, what happens if the first treatment does not work, whether a second opinion is advisable, and whether a clinical trial is available [2].
Conclusion: What to Remember About Brainstem Tumors
A brainstem tumor is a serious condition, but the first step — and often the hardest one — is recognizing the warning signs: balance problems, double vision, slurred speech, swallowing trouble, one-sided weakness, and headaches that are worse in the morning. Because the brainstem is small and densely packed with nerve pathways, even mild or slowly changing symptoms deserve prompt medical evaluation.
Diagnosis centers on MRI with contrast, sometimes followed by biopsy or a spinal tap to pin down the tumor type. Treatment is then matched to the tumor's type, size, and location, combining surgery when safe, radiation, chemotherapy, targeted therapy, and supportive care. And because research into gene-targeted medicines and immunotherapy is moving quickly, clinical trials are worth discussing with your care team.
Next steps: If you or your child has new balance, vision, speech, or swallowing changes that keep getting worse, see a doctor promptly. Seek care right away for sudden trouble walking, changes in breathing rhythm, or ongoing morning headaches with nausea or vomiting.
Frequently asked questions
What are the first signs of a brainstem tumor?
Early signs often involve movement and coordination — trouble walking, clumsiness, dizziness — along with double vision, slurred speech, swallowing difficulty, one-sided weakness, and headaches with morning nausea or vomiting. Because the brainstem is compact, several of these symptoms frequently appear together [1].
Is a brainstem tumor a brain tumor?
Yes. A brainstem tumor is a type of brain tumor that forms in the midbrain, pons, or medulla at the base of the brain, rather than in the cerebrum above. Most are gliomas that start in the glial cells supporting nerve cells [1].
Is brainstem glioma the same as DIPG?
DIPG (diffuse intrinsic pontine glioma) is the former name for what is now usually called diffuse midline glioma. DMG is the most common malignant brainstem tumor in children, tends to grow quickly, usually begins in the pons, and spreads without clear borders, which makes surgery difficult [1].
Can a brainstem tumor be removed with surgery?
Sometimes. Surgery is possible when a tumor is safely reachable — more common with tumors that grow in one area, such as some low-grade gliomas, or tumors that reach open fluid-filled spaces around the brainstem. Many cannot be fully removed because they sit close to areas controlling movement, breathing, and swallowing; in those cases, surgery may remove part of the tumor or relieve pressure [2].
Is there a way to prevent a brainstem tumor?
No known prevention method exists. These tumors form when gene changes inside glial cells cause uncontrolled growth, and the changes usually happen on their own. Research has found no link to diet, stress, lifestyle habits, or environmental exposures [1].
This article is for general education and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional about your individual situation.
Are brainstem tumors more common in children or adults?
Brainstem tumors are more common in children than in adults. Gliomas that start in the pons occur most often in childhood, while adults develop a broader mix of tumor types.
How is a brainstem tumor diagnosed?
Diagnosis starts with a neurological exam that tests balance, eye movement, strength, and swallowing. An MRI with and without contrast is the main test, and sometimes a biopsy or spinal fluid sample is needed.
How are brainstem tumors treated?
Treatment depends on the tumor type, size, and location. Options include surgery when the tumor can be safely reached, radiation therapy, chemotherapy, and targeted medicines for tumors with certain gene changes.
Are all brainstem tumors cancerous?
No. Some, such as many low-grade gliomas, grow slowly and may stay in one place for a long time. Others, such as diffuse midline glioma, are high-grade and grow quickly.
What is the outlook for a brainstem tumor?
The outlook depends greatly on the tumor's type, location, and growth pattern, as well as age. Slow-growing tumors can sometimes be managed for long periods, while fast-growing tumors are harder to control.
Related Reading
Diffuse Midline Glioma (DMG): Symptoms, Causes, Diagnosis & Treatment — Complete Guide explains the most common malignant brainstem tumor in children.
Brainstem: The Essential Connector of Life Functions describes brainstem anatomy and the vital functions it controls.
Childhood Brain Tumors: Types, Symptoms, and Treatment Explained covers the brain tumor types most often seen in children.
Brain Tumor: Symptoms, Causes, Diagnosis and Treatment — What You Need to Know explains brain tumor symptoms, diagnosis, and treatment options.
References
Mayo Clinic Staff. Brainstem tumor - Symptoms and causes. Mayo Clinic. February 6, 2026. https://www.mayoclinic.org/diseases-conditions/brainstem-tumor/symptoms-causes/syc-20595061
Mayo Clinic Staff. Brainstem tumor - Diagnosis and treatment. Mayo Clinic. February 6, 2026. https://www.mayoclinic.org/diseases-conditions/brainstem-tumor/diagnosis-treatment/drc-20595100
National Comprehensive Cancer Network. NCCN Guidelines for Patients: Gliomas. National Comprehensive Cancer Network. 2021. https://www.nccn.org/patients/guidelines/content/PDF/brain-gliomas-patient.pdf
National Cancer Institute. Childhood diffuse intrinsic pontine glioma (DIPG). National Cancer Institute. Updated January 9, 2025. https://www.cancer.gov/types/brain/patient/diffuse-intrinsic-pontine-glioma
Viani GA, et al. Efficacy and safety of hypofractionated radiotherapy versus conventional fractionated radiotherapy in diffuse intrinsic pontine glioma: A systematic review and meta-analysis. Rep Pract Oncol Radiother. 2024;29(3):309-317. PMID 39144263. https://doi.org/10.5603/rpor.100779
Majzner RG, et al. GD2-CAR T cell therapy for H3K27M-mutated diffuse midline gliomas. Nature. 2022;603(7903):934-941. PMID 35130560. https://doi.org/10.1038/s41586-022-04489-4
Wei S, et al. Diffuse intrinsic pontine glioma in the era of H3 K27-altered diffuse midline glioma. Crit Rev Oncol Hematol. 2026;227:105574. PMID 42692100. https://doi.org/10.1016/j.critrevonc.2026.105574
Medical disclaimer
The information provided in this article is for educational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.
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