McKesson Clinical Reference Systems: Women's Health Advisor 2002.2
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Radiation Therapy

What is radiation therapy?

Radiation therapy is controlled use of radiation to stop the growth of cancer cells. Cancer cells are more susceptible to radiation than normal cells. About half of cancer patients have radiation therapy at some point in their treatment.

When is it used?

In some types of cancer, radiation therapy is used for cure. Hodgkin's disease and certain kinds of tumors of the testicles, head, neck, and uterine cervix are some of the cancers that can be cured with radiation.

Radiation therapy may be used to control the spread of a cancer when a tumor cannot be removed by surgery. Or it may be used to control the symptoms of a cancer that has spread. Sometimes radiation therapy is used before surgery to destroy cancer cells around the edges of the tumor.

What happens during the procedure?

Radiation can be delivered to a tumor either externally or internally.

For external radiation, 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 radiation treatment lasts just a few minutes. The total dose is given over several weeks. This allows normal tissues affected by the radiation to recover. 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.

Internal radiation involves implanting radioactive materials in the part of the body to be treated. These materials are left in place for a few hours or many hours, depending on the technology used for the treatment. Once implanted, the radioactive materials generally do not cause any pain. If you have any discomfort, you will be given pain medication.

If you have a radiation implant, you must 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.

What are the benefits of this procedure?

The procedure can cure the cancer or lessen long-term problems by controlling the symptoms of cancer or its spread.

What are the risks associated with this procedure?

If you have a radiation implant, radiation is released from the implant while it is in place. This doesn't make you radioactive. However, while your implant is in place other people at close range are exposed to small doses of radiation. Visitors and hospital staff can spend time in your room as long as they aren't too close and don't stay too long. Hospital staff members may wear a lead apron or shield because they are exposed to radiation more often than your visitors.

The body tissues that are most likely to have side effects from radiation are the skin; the lining of the mouth, stomach, and intestine; and the bone marrow. For example, if radiation is delivered to your neck, it may cause your mouth to be dry. Pelvic radiation therapy may cause diarrhea and may irritate your bladder. Most symptoms go away after your body's cells heal.

Some general side effects that often occur during or soon after radiation therapy are fatigue, nausea, and sometimes vomiting, depending on the area treated. These symptoms are thought to be caused by destruction of tumor cells. The effects are temporary.

There are uncommon but severe complications of radiation therapy. However, cancer can be a life-threatening illness and drastic measures may be necessary. You will need to balance the risks and benefits.

When should I call my health care provider?

Call your health care provider right away if:

  • You develop a fever.
  • You have any change or worsening of pain or symptoms.

Call your provider during office hours if you have questions about the procedure or its result.


Developed by McKesson Clinical Reference Systems.
Published by McKesson Clinical Reference Systems.

This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.

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