Brain metastases happen when cancer spreads from one area of the body to the brain. About 20% of people with cancer develop brain metastases. Most brain metastases occur in people with lung, colorectal, breast, melanoma, or renal cell cancer.
This statistic comes from a
Brain metastases are one of many forms of metastatic cancer, which is cancer that spreads away from the original cancer site.
Metastases increase the risk of dying of cancer, but targeted therapies and whole brain radiation therapy can prolong survival.
In this article, we discuss in detail brain metastases, including their symptoms, diagnosis, treatment, and outlook.
Brain metastases develop when cancer cells from another part of the body enter the bloodstream. This allows them to travel far beyond the original site of the cancer. If cancer cells get through the blood-brain barrier, they can affect the brain.
If cancer cells cause a single tumor in the brain, this is known as a single brain metastasis. Multiple growths are known as brain metastases.
Cancer cells are different from normal cells, because they do not respond to the body’s normal processes that prevent cells from multiplying out of control.
Mutations in cancer cells cause them to multiply quickly without dying, forming tumors that can damage organs.
In most cases, brain metastases could mean that the cancer is terminal. A 2018 analysis found that, out of a total of 145 people, the average survival time was
According to the American Cancer Society, symptoms of brain metastases vary depending on many factors, including how big the tumor or tumors are and where they are in the brain.
Sometimes, brain metastases can bleed, causing sudden and severe symptoms. For example, cancer that affects the temporal lobe may affect language and learning, for which this region of the brain is responsible.
However, not all people with brain metastases experience symptoms. For this reason, ongoing cancer care is critical for catching metastatic cancer early.
Some symptoms that may develop include:
- a chronic or intense headache
- trouble moving one part of the body
- numbness or tingling
- confusion or problems with attention
- changes in behavior or emotions
- nausea or vomiting
Some of these symptoms are similar to those that experts associate with cancer treatment or to the original cancer itself. Therefore, people should not assume the cancer has spread to the brain, based solely on their symptoms.
Instead, they should see an oncologist right away for an assessment.
If a doctor suspects brain metastases, they will usually perform a physical exam and take a complete medical history.
A person might also need a neurological exam to monitor changes in their brain functions, such as thinking.
If the initial exam suggests the cancer may have spread to the brain, a doctor may recommend one or more of the
- Blood tests: Blood tests can help detect some signs of metastatic cancer. They can also show damage to organs, such as the liver.
- CT scans: A CT scan of the head allows a doctor to look at the brain and check for signs of metastatic cancer. However, this test may not show all types of cancer, so a doctor may recommend a follow-up with an MRI scan.
- MRI scans: This test uses magnets to visualize parts of the brain, including blood flow to various brain regions. It can detect signs of brain damage and swelling, as well as the location of brain tumors.
There is no cure for metastatic brain cancer. Treatment typically focuses on several goals:
- slowing or reducing damage to the brain
- prolonging a person’s life
- reducing pain
Some of the treatment options for brain metastases include:
- Steroids: Steroids can reduce swelling in the brain from a tumor. This
may helpwith other symptoms, such as headaches and neurological problems. It will not, however, cure the cancer.
- Surgical removal: It is possible to remove some tumors via surgery. This may prolong survival, and in some cases, it may help a person become cancer-free. However, tumors can regrow later on.
- Whole brain radiation therapy: Whole brain radiation therapy uses radiation to shrink the tumor. While it can prolong survival, it can also cause neurological damage.
- Chemotherapy: Chemotherapy
does not typicallyimprove brain metastases and is not a standard treatment. However, some tumors are susceptible to certain chemotherapy or targeted drugs. If a person has such a tumor, chemotherapy may improve their chances of survival or help them live longer.
- Stereotactic radiosurgery (SRS): This approach uses radiation and targets the tumor rather than the whole brain. Doctors may use SRS alone or in combination with whole brain radiation therapy.
- Psychological support and end-of-life planning: Facing a terminal illness can be extremely difficult. Support groups, psychotherapy, family support, and help to plan the end of a person’s life can make the process feel less overwhelming, empowering a person to choose to live as they prefer.
It is important to discuss the risks and benefits of treatment with a doctor and to think about how treatment might affect quality of life and family relationships during this time.
Metastatic brain cancer is usually terminal. While some people are able to live longer than others and while a few survive much longer than average, most people have months to live by the time they receive a diagnosis.
Even if a surgeon removes tumors from the brain, it is common for them to come back.
Among those who underwent SRS to remove the tumor, the outcome was better, with 72% being free of recurrence at the 1-year mark.
Survival rates for metastatic brain cancer have improved considerably over the last 3 decades due to technologies such as whole brain radiation. Clinical trials continue to test more effective treatments.
Brain metastases occur when cancer cells travel through the bloodstream to the brain, causing tumors to grow.
Symptoms include pain, behavior changes, or seizures. However, not everyone experiences symptoms, so it is important to receive regular monitoring from an oncologist to detect signs early.
Metastatic brain cancer is aggressive and can change a person’s life quickly. There is no right or wrong way to react to a diagnosis. Some people prefer to aggressively treat the cancer, trying everything they can to prolong their life. Others prefer to mitigate pain and maximize time with loved ones.
People may find it beneficial to discuss treatment options as well as get social and emotional support.
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