A brain tumor is a mass or growth of abnormal cells in your brain.
Many different types of brain tumors exist. Some brain tumors are noncancerous (benign), and some brain tumors are cancerous (malignant). Brain tumors can begin in your brain (primary brain tumors), or cancer can begin in other parts of your body and spread to your brain as secondary (metastatic) brain tumors.
How quickly a brain tumor grows can vary greatly. The growth rate as well as the location of a brain tumor determines how it will affect the function of your nervous system.
Brain tumor treatment options depend on the type of brain tumor you have, as well as its size and location.
Types
In most people with primary brain tumors, the cause of the tumor isn't clear. But doctors have identified some factors that may increase your risk of a brain tumor.
Risk factors include:
The signs and symptoms of a brain tumor vary greatly and depend on the brain tumor's size, location, and rate of growth.
General signs and symptoms caused by brain tumors may include:
When to see a doctor
Make an appointment with your doctor if you have persistent signs and symptoms that concern you.
Causes
Brain tumors that begin in the brain
Acoustic neuroma (schwannoma)Open pop-up dialog box
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Primary brain tumors originate in the brain itself or in tissues close to it, such as in the brain-covering membranes (meninges), cranial nerves, pituitary gland or pineal gland.
Primary brain tumors begin when normal cells develop changes (mutations) in their DNA. A cell's DNA contains the instructions that tell a cell what to do. The mutations tell the cells to grow and divide rapidly and to continue living when healthy cells would die. The result is a mass of abnormal cells, which forms a tumor.
In adults, primary brain tumors are much less common than are secondary brain tumors, in which cancer begins elsewhere and spreads to the brain.
Many different types of primary brain tumors exist. Each gets its name from the type of cells involved. Examples include:
Cancer that begins elsewhere and spreads to the brain
Secondary (metastatic) brain tumors are tumors that result from cancer that starts elsewhere in your body and then spreads (metastasizes) to your brain.
Secondary brain tumors most often occur in people who have a history of cancer. Rarely, a metastatic brain tumor may be the first sign of cancer that began elsewhere in your body.
In adults, secondary brain tumors are far more common than are primary brain tumors.
Any cancer can spread to the brain, but common types include:
If it's suspected that you have a brain tumor, your doctor may recommend a number of tests and procedures, including:
A number of specialized MRI scan components — including functional MRI, perfusion MRI and magnetic resonance spectroscopy — may help your doctor evaluate the tumor and plan treatment.
Sometimes other imaging tests are recommended in certain situations, including computerized tomography (CT) and positron emission tomography (PET).
A stereotactic needle biopsy may be done for brain tumors in hard-to-reach areas or very sensitive areas within your brain that might be damaged by a more extensive operation. Your neurosurgeon drills a small hole into your skull. A thin needle is then inserted through the hole. Tissue is removed using the needle, which is frequently guided by CT or MRI scanning.
The biopsy sample is then viewed under a microscope to determine if it's cancerous or benign. Sophisticated laboratory tests can give your doctor clues about your prognosis and your treatment options. Studying your biopsy sample and determining exactly which type of brain tumor you have is a complex process. If you're uncertain about your diagnosis, consider seeking a second opinion at a medical center where many brain biopsies are evaluated every year.
Treatment for a brain tumor depends on the type, size, and location of the tumor, as well as your overall health and your preferences.
Surgery
If the brain tumor is located in a place that makes it accessible for an operation, your surgeon will work to remove as much of the brain tumor as can be done safely.
Some brain tumors are small and easy to separate from surrounding brain tissue, which makes complete surgical removal possible. Other brain tumors can't be separated from surrounding tissue or they're located near sensitive areas in your brain, making surgery risky. In these situations, your doctor removes as much of the tumor as is safe.
Even removing a portion of the brain tumor may help reduce your signs and symptoms.
Surgery to remove a brain tumor carries risks, such as infection and bleeding. Other risks may depend on the part of your brain where your tumor is located. For instance, surgery on a tumor near nerves that connect to your eyes may carry a risk of vision loss.
Radiation therapy
Radiation therapy uses high-energy beams, such as X-rays or protons, to kill tumor cells. Radiation therapy can come from a machine outside your body (external beam radiation), or, very rarely, radiation can be placed inside your body close to your brain tumor (brachytherapy).
External beam radiation can focus just on the area of your brain where the tumor is located, or it can be applied to your entire brain (whole-brain radiation). Whole-brain radiation is most often used to treat cancer that spreads to the brain from some other part of the body and forms multiple tumors in the brain.
Traditionally, radiation therapy uses X-rays, but a newer form of this treatment uses proton beams. Proton beam therapy allows doctors to control the radiation more precisely. It may be helpful for treating brain tumors in children and tumors that are very close to sensitive areas of the brain. Proton beam therapy isn't as widely available as traditional X-ray radiation therapy.
Side effects of radiation therapy depend on the type and dose of radiation you receive. Common side effects during or immediately following radiation include fatigue, headaches, memory loss, scalp irritation and hair loss.
Radiosurgery
Gamma Knife stereotactic radiosurgeryOpen pop-up dialog box
Stereotactic radiosurgery is not a form of surgery in the traditional sense. Instead, radiosurgery uses multiple beams of radiation to give a highly focused form of radiation treatment to kill the tumor cells in a very small area. Each beam of radiation isn't particularly powerful, but the point where all the beams meet — at the brain tumor — receives a very large dose of radiation to kill the tumor cells.
There are different types of technology used in radiosurgery to deliver radiation to treat brain tumors, such as a Gamma Knife or linear accelerator.
Radiosurgery is typically done in one treatment, and usually, you can go home the same day.
Chemotherapy
Chemotherapy uses drugs to kill tumor cells. Chemotherapy drugs can be taken orally in pill form or injected into a vein (intravenously). The chemotherapy drug used most often to treat brain tumors is temozolomide (Temodar). Other chemotherapy drugs may be recommended depending on the type of cancer.
Chemotherapy side effects depend on the type and dose of drugs you receive. Chemotherapy can cause nausea, vomiting, and hair loss.
Tests of your brain tumor cells can determine whether chemotherapy will be helpful for you. The type of brain tumor you have also is helpful in determining whether to recommend chemotherapy.
Targeted drug therapy
Targeted drug treatments focus on specific abnormalities present within cancer cells. By blocking these abnormalities, targeted drug treatments can cause cancer cells to die.
Targeted therapy drugs are available for certain types of brain tumors, and many more are being studied in clinical trials. Your doctor may have your tumor cells tested to see whether targeted therapy is likely to be an effective treatment for your brain tumor.
Rehabilitation after treatment
Because brain tumors can develop in parts of the brain that control motor skills, speech, vision and thinking, rehabilitation may be a necessary part of recovery. Depending on your needs, your doctor may refer you to: