Metastatic Brain Tumor

Sometimes tumors growing in the brain begin there. These are called primary brain tumors. But other types of brain tumors begin as cancers somewhere else in the body. These can start in the lung, breast, skin, kidney, colon, or other body parts. They may spread to the brain even if the cancers are controlled at the original site. These are called secondary or metastatic brain tumors.

In adults, metastatic brain tumors are more common than tumors that begin in the brain. They are also treated differently from those that start in the brain.

Cancer may spread to the brain through your lymph system or your bloodstream. Or it may travel to the brain from a nearby tissue. Metastatic brain tumors are becoming more common because people are living longer after having cancer somewhere else in their body.

In most cases, the metastatic brain tumor is found in the cerebrum. This is the outer part of the brain that controls your thoughts, emotions, and language ability. It also is involved in movement and sensing the outside world. But metastasis can appear in other areas of the brain, too. 

Metastatic brain tumors happen most often in lung cancer. But these tumors can occur in many other types of cancer, such as melanoma or breast cancer.

Symptoms of this condition can vary, depending on the size and number of tumors in the brain and where they occur. These are possible symptoms:

• Trouble walking.
• Mood changes.
• Unusual behaviors.
• Headaches.
• Changes in personality.
• Memory loss.
• Loss of feeling or movement on one side of the body, typically in the arm or leg.
• Trouble speaking.
• Seizures.
• Trouble seeing.
• Vomiting.

Sometimes, your doctor will know if you already have cancer somewhere else in your body. But in some cases, the provider finds the metastatic brain tumor first. Healthcare providers may diagnose this condition using:

• MRI, CT, or PET scan. These are different ways of painlessly creating an image of your brain for the provider to see. A PET scan is often done to determine if there are any other areas of the body with cancer. 
• Cerebral angiography. During this test, dye is injected through a tube put into a blood vessel. Then the provider takes X-rays of your brain. The dye shows the path of the blood flow in your brain. This may help show if a tumor is in your brain. This test is not used much anymore. It has largely been replaced with MRI and CT angiography.
• Spinal tap (lumbar puncture). This test looks for cancer cells in the fluid found around your brain and spinal cord. A spinal tap should not be done if the tumor causes an increase in pressure in your head. 
• Other tests. Your healthcare provider may do scans of other parts of your body to look for the cancer that led to the brain tumor.
• Biopsy of the tumor. This can be a needle biopsy. Or, your provider may remove part or all of the tumor.

A surgeon may be able to remove the tumor during brain surgery. In some cases, the surgeon may only be able to remove part of it. When more than one metastatic brain tumor occurs in the brain, surgical treatment may not always be an option. Other types of surgery may help relieve pressure on the brain and treat symptoms if the tumor can't be removed.

Healthcare providers may be able to treat the brain tumor with radiation. Radiation therapy may involve radiation of the whole brain. Or it may be a more focused radiation treatment (such as with the gamma knife). Chemotherapy is used more often for brain metastasis in order to avoid the side effects of whole brain radiation. In addition, the provider may provide medicines that relieve swelling in the brain, reduce the number of seizures, and relieve pain.

You can take a number of steps to reduce your risk for cancers that can spread to your brain:

• Eat a healthy diet.
• Get regular exercise.
• Stay at a healthy weight.
• Not smoking.
• Limit your sun exposure.
• Have regular screening exams for certain cancers, such as mammograms for breast cancer or tests to look for colorectal cancer.

Sometimes, healthcare providers won’t be able to cure this disease. In some cases, they will suggest methods to keep a person comfortable during his or her remaining time. These may include specific treatments and medicine to reduce pain and other symptoms.