Brain Cancer Metastatic

Brain metastases occur when cancer from another part of your body spreads to your brain, forming one or more new tumors that can affect how you think, move, and feel.

Table of contents

• What Are Brain Metastases
• How Common Are Brain Metastases
• What Causes Brain Metastases
• Symptoms of Brain Metastases
• How Brain Metastases Are Diagnosed
• Treatment Options
• Living With Brain Metastases

What Are Brain Metastases

Brain metastases happen when cancer cells spread from their original location in your body to your brain. The cancer that starts in another part of your body is called the primary tumor or primary cancer. When these cancer cells break away and travel through your bloodstream, they can reach your brain and form one or more new tumors there.^[1][2]

This type of brain tumor is different from primary brain cancer, which starts in the brain itself. Brain metastases are also called metastatic brain tumors or secondary brain tumors. They are much more common than primary brain cancer.^[2][4]

Once cancer cells reach your brain, they form tumors that grow and put pressure on the surrounding brain tissue. Where these tumors form in your brain affects what symptoms you experience. The most common place for brain metastases is the cerebrum, which is the largest part at the top of your brain. Less often, cancer spreads to the cerebellum and brain stem.^[4]

Sometimes cancer can also spread to the meninges, the membrane that covers the brain and spinal cord. This is called leptomeningeal metastases or meningeal carcinomatosis.^[4]

How Common Are Brain Metastases

Brain metastases are the most common type of brain tumor in adults. Experts estimate that 10% to 30% of people with cancer that starts outside the brain will develop a metastatic brain tumor at some point.^[2][6]

The number of people developing brain metastases is growing. This increase is happening for several reasons. Better treatments for other cancers help people live longer, but these treatments don’t always protect the brain. More sensitive imaging tests can now find small brain tumors that might have been missed before. The chances of getting diagnosed with brain metastases increase after age 45, with most people diagnosed when they’re over 65.^[2]

In the United States, an estimated 98,000 to 170,000 new cases of brain metastases occur each year.^[6]

What Causes Brain Metastases

Any type of cancer can spread to the brain, but some cancers are more likely to do so than others. Cancer cells break away from the original tumor and travel through your bloodstream until they reach your brain. Scientists aren’t completely sure why some primary cancers are more likely to spread to the brain.^[2]

The most common types of cancer that spread to the brain are:^[1][2][4]

• Lung cancer: About half of all people with lung cancer develop brain metastases. This accounts for roughly half of all brain metastases. Small cell lung cancer is especially likely to spread to the brain.
• Breast cancer: Approximately 10% to 15% of people with metastatic breast cancer develop brain metastases. It’s more common in certain types like HER2-positive breast cancer and triple-negative breast cancer.
• Melanoma: About half of people with melanoma (a type of skin cancer) develop brain metastases.
• Kidney cancer: Also called renal cancer, this can spread to the brain.
• Colorectal cancer: Cancer of the colon or rectum can metastasize to the brain.

Less often, brain metastases arise from prostate cancer, thyroid cancer, and other types of cancer.^[2][5]

Symptoms of Brain Metastases

The symptoms you experience depend on where the tumors are located in your brain, how large they are, and how fast they’re growing. Different areas of the brain control different functions. For example, if a tumor is near the front of your brain, it might affect your memory or mood. If it’s near the back, it might affect your balance or vision.^[1][2]

The most common symptoms of brain metastases include:^[1][2][4]

• Headaches, sometimes with nausea and vomiting
• Seizures (uncontrolled electrical activity in the brain that can cause jerking movements or changes in awareness)
• Weakness or numbness on one side of your body
• Problems with memory, thinking, or changes in mood and personality
• Difficulty speaking or understanding language
• Vision problems, particularly on one side
• Problems with balance and coordination
• Loss of bladder or bowel control

As brain metastases grow larger or more tumors develop, you may notice additional symptoms such as problems hearing, swallowing, or double vision. Drowsiness is the most common symptom in advanced brain metastases.^[2]

Most symptoms from brain metastases come on slowly and worsen over time. This is different from a stroke, where symptoms appear suddenly.^[2]

Many symptoms happen because the growing tumor increases pressure inside your skull. Your skull is made of bone and has a fixed amount of space, so when a tumor grows or causes swelling, it creates increased pressure called raised intracranial pressure.^[4]

How Brain Metastases Are Diagnosed

If you have cancer and experience symptoms that suggest a brain tumor, your healthcare provider will perform tests. Even without symptoms, your provider may screen you for brain metastases if you have a type of cancer that commonly spreads to the brain.^[2]

Medical history and physical exam: Your doctor will ask about your symptoms and medical history, including any previous cancer diagnosis. During a physical exam, your doctor may test your reflexes, strength, balance, coordination, and sensation. They may also check your vision, hearing, and mental status. These tests help identify which part of your brain might be affected.^[2][4]

Neurological exam: This focused examination looks for changes in your balance, coordination, mental status, hearing, vision, and reflexes. These changes can point to the specific area of your brain where the tumor is located.^[2][9]

Magnetic Resonance Imaging (MRI): An MRI is usually the first imaging test used to check for brain tumors. It uses magnets and radio waves to create detailed pictures of your brain. An MRI can identify the number, location, and size of tumors. It can find very small tumors and tumors that are deeper in the brain. You may receive an injection of contrast dye during the test to make the images clearer.^[4][9]

Computed Tomography (CT) scan: If an MRI can’t be done (for example, if you have a pacemaker or certain metal devices in your body), a CT scan is used instead. A CT scan uses X-rays to create detailed images of your brain.^[4][9]

Biopsy: Your doctor may recommend removing a small sample of tissue for examination under a microscope. This can be done with a needle or during surgery to remove the tumor. A biopsy helps confirm the diagnosis and identify what type of cancer has spread to your brain.^[4][9]

Blood tests: You may need blood work to check for tumor markers (substances that tumors release into your bloodstream).^[2]

Treatment Options

Treatment for brain metastases aims to control the cancer, relieve symptoms, slow tumor growth, and help you maintain your quality of life. Your healthcare team will consider many factors when recommending treatment, including the type of primary cancer, the number and size of brain tumors, their location, your symptoms, your overall health, and your treatment goals.^[1][9]

People with brain metastases often need a combination of treatments. Leading cancer centers have teams of specialists who work together to create a personalized treatment plan for each patient.^[5]

Surgery

Surgery may be an option if you have one or a small number of tumors that can be safely removed. Brain surgery is not suitable for everyone. It’s a major operation and requires you to be in good overall health. Surgery may not be possible if tumors are widely spread throughout the brain or located in areas that are difficult to reach.^[5][15]

Radiation Therapy

Radiation therapy uses high-energy X-rays to kill cancer cells. There are different types of radiation therapy for brain metastases:^[4][9][15]

Stereotactic radiosurgery: Despite its name, this is not surgery. It delivers focused radiation beams from many different angles that meet at the tumor site. The cancer receives a high dose of radiation while surrounding healthy tissue receives much less. This treatment is often used for one to three small tumors. The full dose may be given in a single treatment session.^[15]

Whole brain radiation therapy: This treats the entire brain and is typically used when there are many tumors spread throughout the brain. You usually receive treatment once a day for one to two weeks. Healthcare providers may use special techniques to reduce damage to important parts of the brain.^[15]

Medications

Several types of medications can help treat brain metastases:^[1][9]

Steroids: These medications, also called corticosteroids, help reduce swelling around brain tumors. This can relieve symptoms and prevent complications from increased pressure in the skull. Steroids are usually given for short periods and the dose is gradually reduced to avoid side effects.^[9][15]

Chemotherapy: These drugs kill cancer cells throughout the body. However, many chemotherapy drugs cannot cross the blood-brain barrier, a natural filter that protects the brain, so they may not be effective for brain metastases.^[1]

Targeted therapy and immunotherapy: Newer systemic therapies are showing promise for treating brain metastases. These treatments target specific characteristics of cancer cells or help your immune system fight cancer.^[1][10]

Anti-seizure medications: If you experience seizures, your doctor will prescribe medication to help control them.^[9]

Other Treatment Options

Laser Interstitial Thermal Therapy (LITT): This uses heat from a laser to destroy tumors through a small incision. Advanced imaging and robotic technology help target the tumor while protecting healthy brain tissue.^[14]

For some people with progressive disease, limited treatment options, and poor overall health, palliative care or best supportive care may be the most appropriate choice. This focuses on managing symptoms and maintaining quality of life.^[1]

Living With Brain Metastases

A diagnosis of brain metastases can bring many emotions including fear, sadness, confusion, and anger. These feelings are completely normal. Taking care of your emotional health is just as important as caring for your physical health.^[18]

For many people, learning that cancer has returned and spread to the brain after initial treatment can feel devastating. It’s okay to feel overwhelmed, and you don’t have to be strong all the time. Try to take things one day at a time and be gentle with yourself.^[18]

Staying Healthy

While brain metastases cannot be cured, people are living longer after diagnosis, and there are many things you can do to feel better and protect your brain:^[16]

Physical activity: Exercise is one of the best things you can do for your brain health. Even light activity can help improve your mood, energy, and overall well-being.^[16]

Support and counseling: Talking to someone you trust can help you cope. This might be a friend, family member, healthcare provider, counselor, or other people in similar situations. Many hospitals offer support groups specifically for people with brain metastases.^[18]

Coordinated care: Many cancer centers have nurse navigators who serve as a single point of contact. They can answer your questions, coordinate appointments with different specialists, and connect you with support services.^[14]

Additional support: Healthcare teams can help with many needs, including pain control, nutrition, financial counseling, social work services, and spiritual support.^[14]

Even with a serious diagnosis, treatment advances mean many people can live longer with good quality of life. Working closely with your healthcare team and taking an active role in your care can help you make the most of your treatment.^[5]