Radiation Therapy for Brain Tumors
Understanding Radiation Therapy
Radiation therapy, sometimes called radiotherapy, is the careful use of radiation to safely and effectively treat many different kinds of tumors.
Doctors called radiation oncologists use radiation therapy to try to kill tumors, to control tumor growth or to relieve symptoms. Radiation therapy works 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 Options for Brain Tumors
People with brain tumors should discuss treatment options with several cancer specialists, including a radiation oncologist. A radiation oncologist is a doctor who will help you understand the types of radiation therapy available to treat your tumor. Conventional radiation therapy treatment options for brain tumors include:
- External beam radiation therapy.
- Brachytherapy or internal radiation therapy.
External Beam Radiation Therapy
External beam radiation therapy involves a series of daily outpatient treatments over several weeks to accurately deliver radiation to the brain. Radiation is often given after surgery, and sometimes it is used instead of surgery.
- 3-dimensional conformal radiotherapy (3D-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 brain tumor while keeping radiation away from nearby organs, such as the eyes.
- Intensity modulated radiation therapy (IMRT) is the most recent advance in the delivery of radiation. IMRT differs from 3D-CRT by modifying the intensity of the radiation within each of the radiation beams.
- Stereotactic radiotherapy, sometimes called radiosurgery, is a type of external beam radiation therapy that pinpoints high doses directly on the tumor, in some cases in only one treatment.
- Proton therapy is given much the same way as external beam therapy, but it uses proton particles rather than X-rays to kill brain tumor cells. This treatment is only available in a few regions of the country.
Internal Radiation Therapy
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 will 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.
Doctors are constantly exploring newer and better ways to treat primary brain tumors.
- Drugs that make tumor cells more sensitive to radiation are called radiosensitizers. Combining radiation with radiosensitizers may allow doctors to kill more tumor cells.
- Chemotherapy is used with radiation to treat some brain tumors. Your doctor may recommend that you consult with a medical oncologist (chemotherapy doctor) before starting radiation.
Potential Side Effects
The effects of brain radiation can vary depending on your tumor and the technique used to treat it.
- Before treatment, your radiation oncologist will discuss any side effects, however rare, you may experience.
- Possible side effects can include fatigue, change in appetite, headaches, visual changes, hair loss, skin irritation, nausea, vomiting and/or unsteadiness.
Some side effects can be treated with steroids or other medications. Talk to your doctor about any problems you experience.