A brain tumor is a mass or growth of abnormal cells in your brain or close to 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 (secondary, or metastatic, brain tumors).
Symptoms
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:
· New onset or change in pattern of headaches
· Headaches that gradually become more frequent and more severe
· Unexplained nausea or vomiting
· Vision problems, such as blurred vision, double vision or loss of peripheral vision
· Gradual loss of sensation or movement in an arm or a leg
· Difficulty with balance
· Speech difficulties
· Confusion in everyday matters
· Personality or behavior changes
· Seizures, especially in someone who doesn't have a history of seizures
· Hearing problems
Causes
Brain tumors that begin in the brain
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 acquire errors (mutations) in their DNA. These mutations allow cells to grow and divide at increased rates and to continue living when healthy cells would die. The result is a mass of abnormal cells, which forms a tumor.
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.
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. But in rare cases, a metastatic brain tumor may be the first sign of cancer that began elsewhere in your body.
Secondary brain tumors are far more common than are primary brain tumors.
Any cancer can spread to the brain, but the most common types include:
· Breast cancer
· Colon cancer
· Kidney cancer
· Lung cancer
· Melanoma
Risk factors
In most people with primary brain tumors, the cause of the tumor is not clear. But doctors have identified some factors that may increase your risk of a brain tumor. Risk factors include:
· Your age. Your risk of a brain tumor increases as you age. Brain tumors are most common in older adults. However, a brain tumor can occur at any age. And certain types of brain tumors occur almost exclusively in children.
· Exposure to radiation. People who have been exposed to a type of radiation called ionizing radiation have an increased risk of brain tumor. Examples of ionizing radiation include radiation therapy used to treat cancer and radiation exposure caused by atomic bombs.
More common forms of radiation, such as electromagnetic fields from power lines and radiofrequency radiation from cellphones and microwave ovens, have not been proved to be linked to brain tumors.
· Family history of brain tumors. A small portion of brain tumors occur in people with a family history of brain tumors or a family history of genetic syndromes that increase the risk of brain tumors.
Diagnosis
· A neurological exam. A neurological exam may include, among other things, checking your vision, hearing, balance, coordination, strength and reflexes. Difficulty in one or more areas may provide clues about the part of your brain that could be affected by a brain tumor.
· Imaging tests. Magnetic resonance imaging (MRI) is commonly used to help diagnose brain tumors. In some cases a dye may be injected through a vein in your arm during your MRI study.
Other imaging tests may include computerized tomography (CT) scan and positron emission tomography (PET).
· Tests to find cancer in other parts of your body. If it's suspected that your brain tumor may be a result of cancer that has spread from another area of your body, your doctor may recommend tests and procedures to determine where the cancer originated. One example might be a CT scan of the chest to look for signs of lung cancer.
· Collecting and testing a sample of abnormal tissue (biopsy). A biopsy can be performed as part of an operation to remove the brain tumor, or a biopsy can be performed using a needle.
The biopsy sample is then viewed under a microscope to determine if it is cancerous or benign. This information is critical to establish a diagnosis and prognosis and, most importantly, in guiding treatment.
Treatment
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 possible.
In some cases, tumors are small and easy to separate from surrounding brain tissue, which makes complete surgical removal possible. In other cases, 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, in very rare cases, 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 has spread to the brain from some other part of the body.
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 and scalp irritation.
Radiosurgery
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.
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), which is taken as a pill. Many other chemotherapy drugs are available and may be used 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.
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.
Rehabilitation after treatment
Speech therapy session
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. Your doctor may refer you to services that can help, such as:
· Physical therapy can help you regain lost motor skills or muscle strength.
· Occupational therapy can help you get back to your normal daily activities, including work, after a brain tumor or other illness.
· Speech therapy with specialists in speech difficulties (speech pathologists) can help if you have difficulty speaking.
· Tutoring for school-age children can help kids cope with changes in their memory and thinking after a brain tumor.
