What is radiation therapy?
Radiation therapy is the use of high-energy radiation 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.
When is it used?
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:
- Shrink a tumor before surgery to remove it. This makes
it easier to remove the tumor.
- Destroy cancer cells that are left after surgery or
other treatments.
- Work with another treatment, such as chemotherapy, to
destroy the cancer.
- Help control pain, pressure, and other symptoms of cancer
even if a cure is not possible.
What happens during the procedure?
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 to
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.
What are the side effects of radiation therapy?
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:
- skin sores
- loss of head and body hair
- increased risk of infection
- bleeding problems
- nausea, vomiting, and diarrhea
- weakness, tiredness, and fatigue
- sores in the mouth.
To help relieve skin problems caused by radiation treatment:
- Avoid tight or scratchy clothing that irritates the skin.
- Use lukewarm water and mild soap for bathing.
- Avoid being in the sun. When you are outside, put
sunscreen with an SPF of 15 or higher on exposed parts of
the body.
- Do not use any powders, creams, perfumes, deodorants,
body oils, ointments, or lotions without first checking
with your provider. They may interfere with your
treatment.
To help you deal with the fatigue get plenty of rest and
sleep.
If you have a loss of appetite:
- Eat frequent small meals.
- Snack between meals.
- Add extra protein to your diet by eating more cheese,
meat, fish, nuts, and soy products.
- Use nutritional supplements as directed by your provider.
- Ask a friend or family member to prepare food if cooking
odors bother you.
To reduce nausea and vomiting:
- Eat small meals throughout the day.
- Avoid sweets and fried or fatty foods.
- Eat food heated to room temperature.
- Eat slowly, and chew food well.
- Eat dry foods like toast or crackers to help ease an
upset stomach.
- Avoid food odors that increase nausea.
- Drink cool, unsweetened, and noncarbonated drinks, such
as apple juice or flat ginger ale.
To help relieve diarrhea:
- Change to a clear liquid diet.
- Drink plenty of fluids, such as apple juice and flat
sodas.
- Avoid milk and other dairy products if they make the
diarrhea worse.
If the side effects become severe, treatment may be stopped
for a while, or the dose lowered. In extreme cases,
treatment may be discontinued.
What are the benefits of this procedure?
The procedure can cure or help cure the cancer or lessen
the symptoms of cancer or its spread.
What are the risks associated with this procedure?
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.
When should I call my health care provider?
Call your 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.
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.
Copyright © 2005 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved.