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 some 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 malignant disease when a tumor cannot be removed by surgery, or to control the symptoms of cancer that have 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.

In external radiation, a machine directs a beam of radiation at the tumor. Temporary marks on the skin help the radiation technician target the exact area to be treated. The radiation oncologist (a doctor who specializes in treating tumors with radiation) calculates the dose of radiation to use on the tumor. Each radiation treatment lasts only a few minutes. The total dose is given over several weeks to allow normal tissues affected by the radiation to recover. You may have treatment for several days in a row, followed by several days off. The pattern is repeated until the total dose of radiation is given.

Internal radiation consists of 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. Sometimes hospital staff members wear a lead apron or shield because they are exposed to radiation more often than your visitors.

The side effects of radiation therapy are fairly predictable. The body tissues that are most susceptible to 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 the neck area, temporary symptoms such as dry mouth may occur. Pelvic radiation therapy may cause mild to moderate diarrhea and possibly bladder irritation. Most symptoms go away after your body's cells heal.

Some general side effects that commonly occur during or soon after radiation therapy are fatigue, nausea, and occasionally 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 potential risks and benefits.

When should I call the doctor?

Call the doctor immediately if:

• You develop a fever.

• You have any change or worsening of pain or symptoms.

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