The brain is the center of thought, memory, emotion, speech, sensation and motor function. The spinal cord and special nerves in the head called cranial nerves carry and receive messages between the brain and the rest of the body.
There are two general types of brain tumors:
Primary – a tumor that starts in the brain. Primary brain tumors can be benign (not cancerous) or malignant (cancerous). Primary tumors in the brain or spinal cord rarely spread to distant organs.
Metastatic – a tumor caused by cancer elsewhere in the body that spreads to the brain. Metastatic brain tumors are always cancerous. Brain tumors cause damage because, as they grow, they can interfere with surrounding cells that serve vital roles in our everyday life.
If doctors determine that you have a brain tumor, the treatment options and prognosis are based on many factors, including tumor type, location and size of the tumor, how aggressive it appears (grade), as well as your age and health. Depending upon these and other factors, surgery, radiation therapy and medical therapy are possible treatment options.Radiation Therapy
Radiation therapy, sometimes called radiotherapy, is the careful use of high-energy X-rays to safely and effectively treat brain tumors. Radiation works noninvasively within tumor cells by damaging their ability to multiply. When these cells die, the body naturally eliminates them. Healthy cells near the tumor may be affected by radiation, but they are able to repair themselves in a way tumor cells cannot. Radiation therapy can be used after surgery, or in some cases when surgery isn’t safely possible. Ask your radiation oncologist more about whether radiation will be helpful for your treatment.Surgery
For many brain tumors, surgery is a curative part of treatment. A neurosurgeon will usually perform one surgical biopsy to determine what kind of tumor you have. Often, that is the definitive surgery. Surgery can be done to maximize tumor removal while minimizing nerve injury or effects on your normal functioning. Depending upon what tumor you have, surgery may be the only local treatment needed. However, often radiation is used after surgery to lessen the chances of recurrence or further tumor growth. Ask your surgeon more about the extent of surgery best for you.
External beam radiation therapy involves a series of outpatient treatments with a machine called a linear accelerator, or linac. The radiation beam is painless and treatment lasts only a few minutes. Treatments are given daily, Monday through Friday, usually over three to seven weeks.
Before beginning treatment, you will be scheduled for a planning session to map out the area your radiation oncologist wishes to treat. This procedure is called a simulation. Simulation involves lying on a table, usually with a form-fitting mask to make sure treatment can be delivered the same way each time. A CT scan is performed with that mask, and then your doctor will design individualized treatment, often with information from other CT scans and MRIs you have had. Marks are made on the mask, not your skin, to help the radiation therapist precisely position you for daily treatment.
Different techniques can be used to give radiation for brain tumors. 3-dimensional conformal radiotherapy (3-D CRT) combines multiple radiation treatment fields to deliver precise doses of radiation to the brain. Tailoring each of the radiation beams to the patient’s tumor allows coverage of the diseased cells while keeping radiation away from nearby organs, such as the eyes.
Intensity modulated radiation therapy (IMRT) is a form of 3-D CRT that further modifies the intensity of the radiation within each of the radiation beams. Stereotactic radio therapy can be used in some tumors to be even more precise. At most centers, X-rays (photons) are used for treatment. Proton beams are different from X-rays, and can give less radiation to normal tissue. All three more precise techniques can be used for tumors in particularly sensitive areas. Ask your radiation oncologist about which technique is best for treating your tumor.
Internal radiation therapy, or brachytherapy, works by placing radioactive sources in, or just next to, a tumor. During brachytherapy, a tube or balloon called a catheter may be inserted into the brain. The radiation will then be carried to the tumor using this catheter. The radioactive source will then be left in place from several hours to several days to kill the tumor cells. In some cases, the radiation is permanently placed directly into the tumor or the area where the tumor was before surgery. This is less commonly used for treatment than external beam radiation therapy.
It is important to care for yourself as well as possible during radiation therapy.
Completing treatment and recovery can be challenging. Seek out help from support groups and friends ahead of time. If you have a support network in place before and during treatment, it will be easier to get through side effects since people you can count on will be around to help you. If you need additional support, let your nurse or doctor know.
The side effects you may experience will depend on the area being treated and the type of radiation used. Before treatment, ask your doctor to describe what you can expect. Some patients experience minor or no side effects and can continue their normal routines.
© American Society for Radiation Oncology, 2012.