A metastatic tumor (metastasis) in the brain is a cancer deposit which spreads from another part of the body. Often, there may be multiple lesions in the brain.
Almost any patient with a diagnosis of cancer is at risk for developing a brain metastasis. However, underlying lung cancer is the most common source of a brain metastasis. Other cancers which are apt to spread to the brain include breast, renal cell and GI (gastrointestinal) cancers. Melanoma has the highest rate of spreading to the brain.
Following treatment, brain metastases can recur (occur again). A tumor can grow back at the site of previous treatment or develop at a different location in the brain.
Signs and Symptoms
Symptoms of a brain metastasis usually depend on its size and location. Some are discovered before they produce any symptoms and some produce symptoms as a result of their number.
Beyond seizures or loss of specific neurological functions due to a brain metastasis, other factors need to be considered. These include the extent of cancer outside the brain, the volume and number of brain metastases, your general well-being, your ability to perform daily activities (as defined on standardized assessment scales) and your age.
Depression, anxiety and fatigue are not uncommon. Some chemotherapy agents also affect mood, alertness and mental status.
Symptoms from a brain metastasis (such as headache, seizure or a loss of a neurological function) may lead to the discovery of a previously undiagnosed underlying cancer. Often, brain metastasis occurs after a primary underlying cancer has been identified or has undergone some level of treatment.
Several diagnostic tests may be used. Magnetic resonance imaging MRI with and without contrast is the “gold standard” imaging test for brain metastases. Computerized tomography CT with and without contrast may be used when patients are unable to have an MRI scan. Additional tests include MR spectroscopy , MR perfusion and brain positron emission tomography (PET) scans. CT scan of the chest/abdomen/pelvis and PET/CT scan of the body are used for evaluation of the primary cancer.
A customized treatment plan is put together for you based on:
- Your primary cancer
- Location, size and tumor symptoms
- Metastatic tumor burden in your brain (volume and number)
- Your age, general health and daily level of activity
- Your tolerance for treatment
- Your preferences
Treatment for a brain tumor may include one or a combination of the following options:
- Surgery is done to establish the diagnosis or to relieve symptoms from the bulk or pressure associated with the brain metastasis. When an underlying cancer has not been been identified or when more than one cancer is present, a stereotactic biopsy may be done to establish the exact diagnosis. This surgery is often done when there are multiple brain lesions or the metastasis is in an area which is poorly accessible for surgery. Craniotomy (open or minimally invasive) is often used to remove a larger solitary metastasis or a symptomatic tumor, especially if it is expected to be poorly or slowly responsive to radiation or other therapies.
- Anti-seizure medicines These medications may be used around the time of a craniotomy or to treat seizures.
- Radiation therapy (especially stereotactic radiosurgery ) is often used as part of the treatment.Whole brain radiation is now used only in very selected cases.
- Chemotherapy is used most often for the treatment of the primary cancer. Many brain metastases do not respond well to chemotherapy treatments.
- Immunotherapy and systemic targeted therapy is a developing area of treatment which is being used in some brain metastases from melanoma, breast cancer and NSCLC (non-small cell lung cancer)
- Steroid medication These medicines may provide temporary relief of symptoms from swelling around the tumor.
Allied services should be considered as part of the spectrum of care and management. These include therapies (physical, speech and occupational), social services, cancer patient advocacy and support groups, hospital and community resources (to assist you and your family with financial, insurance and legal issues), hospice and palliative care resources.
Follow-up care includes regular monitoring for worsening of symptoms, effectiveness of treatment and possible recurrent disease.