Radiation therapy is the use of high-energy radiation (such as high-energy X-rays) to kill cancer cells and shrink tumors. Radiation can kill cells or keep them from growing. Cancer cells grow and divide more quickly than normal cells. This means that carefully planned doses of radiation can kill or stop the growth of cancer cells, while most normal cells are able to recover from the radiation.
More than half of all people with cancer have radiation therapy at some point in their treatment. Radiation therapy is sometimes called X-ray therapy, radiotherapy, or irradiation.
Radiation therapy alone can cure some cancers, such as Hodgkin's disease. However, it is most often combined with surgery or chemotherapy to control symptoms or spread of the cancer. Radiation may be used to:
There are 2 kinds of radiation therapy: external and internal. External radiation is delivered from outside the body. For internal radiation, a radiation source is placed next to or in a tumor.
External radiation is usually given during outpatient visits to a hospital or treatment center. A machine directs a beam of radiation at the tumor. Temporary marks on the skin help the radiation technologist target the exact area to be treated. The radiation oncologist calculates the dose of radiation to use on the tumor. (A radiation oncologist is a doctor who specializes in treating tumors with radiation.)
Each external radiation treatment lasts just a few minutes. The treatment is painless. Small daily doses are given so that the body can tolerate the treatment better and normal tissues affected by the radiation can recover. The total dose is given over several weeks. For example, you may have treatment for several days in a row, followed by several days without treatment. This pattern is repeated until you have received the total dose of radiation.
For internal radiation therapy, a radioactive material is put inside the body. It may be left in place for a few hours or many hours. Once implanted, the radioactive material generally does not cause any pain. If you have any discomfort, you will be given pain medicine. In some cases you may swallow the radioactive material, or it may be injected into your body.
If you have internal radiation therapy, you will need to stay in your hospital room while the implant is in place. Depending on the type of implant, you may be asked to stay in bed.
Radiation therapy can cause damage to normal cells in the area of the tumor as well as death of tumor cells. Side effects depend on the area of the body that is receiving the radiation treatment. Some possible side effects are:
To help relieve skin problems caused by radiation treatment:
To help you cope with the fatigue, get plenty of rest and sleep.
If you have a loss of appetite:
To reduce nausea and vomiting:
To help relieve diarrhea:
If the side effects become severe, treatment may be stopped for a while, or the dose lowered. In extreme cases, treatment may be discontinued.
Radiation therapy can cure or help cure the cancer or lessen the symptoms of cancer or its spread.
External radiation does not make you radioactive. If you have internal radiation treatment, the radioactive material may send its high-energy rays outside your body. This means that other people in close range may be exposed to small doses of radiation. Visitors and hospital staff can spend time in your room as long as they are not too close and do not stay too long. Hospital staff members may wear a lead apron or shield because they are exposed to radiation more often than your visitors.
There are uncommon but severe complications of radiation therapy. However, cancer can be a life-threatening illness and the benefits of the treatment are usually greater than the risks. You and your provider will discuss the risks and benefits.
Call your provider right away if:
Call your provider during office hours if you have questions about the procedure or its result.