Brain Metastases
Brain metastases (mets) are areas of cancer that spread to the brain from another part of the body. This can cause problems such as nausea, vision problems, headache, and seizures.
Sometimes, brain mets are found at the same time as the primary cancer. Other times, they may not show up until much later, sometimes months or even years after the first diagnosis.
What types of cancer spread to brain?
The most common cancers that spread to the brain are lung cancer, breast cancer, and melanoma, but other cancers can also cause brain mets.
Brain mets are usually single spots, but some types of cancer (like small cell lung cancer) can cause many different spots. Other types can cause meningitis (swelling of the linings of the brain). This is mostly seen with leukemias, lymphomas, or very advanced forms of other types of cancer.
Symptoms of brain metastases
Not everyone with a brain metastasis will have symptoms but most do. Symptoms of brain mets depend on the location, size, and number of growths in the brain and the amount of swelling they cause. Metastases can push on or cause swelling in specific areas causing specific symptoms.
The most common symptoms are:
- Headache
- Not being able to move parts of your body, like an arm or leg
- Sleepiness
- Memory problems
- Changes in emotions or how a person acts (confusion)
- Problems hearing, seeing, or swallowing
- Seizures
- Nausea or vomiting
How are brain metastases found?
Brain mets may be found because a person is having symptoms, or if the doctor is looking to see if the cancer has spread anywhere else in the body. Brain mets may be seen on imaging tests such as:
- MRI
- CT or CAT scan
- PET scan
Sometimes, a brain biopsy may also be done but it’s not always needed.
Treatment of brain metastases
Brain mets can be treated in different ways, depending on the number of brain mets and the symptoms they cause:
- Steroid medicines, like dexamethasone, are often used to reduce swelling in the brain around the mets. This can often help with symptoms right away while further treatment is planned.
- Anti-seizure medicines may also be used if you have had a seizure. This can help prevent more seizures.
- Radiation therapy is often used to manage brain mets and control symptoms. This may involve whole brain radiation if you have several brain mets or meningitis from cancer or stereotactic radiosurgery (SRS) if you have a single met.
Chemotherapy (chemo) is not usually a treatment for brain mets because many of these medicines have a hard time getting into the brain. However, for people with meningitis from cancer, chemo may be injected right into the fluid that surrounds the brain and spinal cord. This can be done using a lumbar puncture (needle into the back) or through a device called an Ommaya reservoir placed under the scalp.
Treatments for brain mets can help control symptoms, improve quality of life, and sometimes help people live longer. But they can also come with side effects. Ask your cancer care team about:
- The goal of treatment
- What to expect during and after treatment
- Possible side effects or risks
- How each option might affect your daily life
It’s important to understand your treatment options so you can decide what’s right for you.
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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).
American Society of Clinical Oncology. Brain tumor: Types of treatment. Cancer.net. Content is no longer available.
American Society of Clinical Oncology (ASCO). What is metastasis? Accessed at cancer.net. Content is no longer available.
Shih, HA. Epidemiology, clinical manifestations, and diagnosis of brain metastases. UpToDate. Updated May 23,2025. Accessed at https://www.uptodate.com/contents/epidemiology-clinical-manifestations-and-diagnosis-of-brain-metastases on July 9, 2025.
Shih, HA. Overview of the treatment of brain metastases. UpToDate. Updated March 11, 2025. Accessed at https://www.uptodate.com/contents/overview-of-the-treatment-of-brain-metastases on July 9, 2025.
Sniff et al. Radiation therapy for brain metastases: ASCO guideline for endorsement of ASTRO guideline. JCO.2022; 40(20):2271-2276. doi:10.1200/JCO.22.00333
Last Revised: July 30, 2025
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