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Radiation Therapy

About half of all people with cancer receive radiation therapy, a type of treatment that is used to shrink tumors and stop the growth of cancer cells.

Here are the facts on radiation therapy, including what it is, what to expect, and how to cope with side effects.

What Is Radiation Therapy?

Cancer is a disease that causes cells to grow abnormally and out of control. In radiation therapy, high-energy X-rays are directed at a person's body to kill cancer cells and keep them from growing and multiplying.

Most people have been exposed to radiation in the form of an X-ray — most likely at a dentist's office. And just like the X-rays given in the dentist's office, radiation therapy is painless. But unlike a typical X-ray, the radiation isn't used just to create a picture of a tooth or broken bone. Radiation therapy delivers higher doses of radiation so it will kill cancer cells and shrink tumors.

While it's killing the cancer, radiation therapy also can damage normal cells. The good news is that normal cells usually recover from the effects of radiation. Doctors take precautions to protect a person's healthy cells when they're giving radiation treatments.

How Is Radiation Given?

Doctors can give people with cancer radiation therapy as the only form of treatment. Or they may use a combination of radiation therapy and chemotherapy (using medicines or chemicals to destroy cancer cells) to fight the cancer. Other people with cancer may have surgery to remove tumors or cancer cells first and then have radiation therapy.

Each person's situation and treatment is different. A person who has cancer will see an oncologist (pronounced: on-KAHL-uh-jist), a doctor who specializes in cancer treatment.

A radiation oncologist is a doctor whose specialty is using radiation to treat cancer. The radiation oncologist will work with others on the health care team to decide on the type and dose of radiation therapy that will best treat a person's cancer.

Radiation therapy can be given two ways:

  1. externally, through the skin
  2. internally, through injection or by implanting a radioactive pellet in the body. Internal radiation therapy is very rare in teens — it's usually adults who get this form of treatment.

With external radiation therapy, doctors use a large machine and special equipment that aims specific amounts of radiation directly at the cancer.

What Happens During External Radiation Therapy?

People who are having external radiation treatments usually don't need to stay in the hospital overnight. Most visit the hospital or treatment center 5 days a week (with weekends off) for 2 to 8 weeks. Getting small daily doses of radiation helps to protect the normal cells from damage. The weekend breaks help the normal cells to recover from radiation.

If you're being treated using external radiation therapy, at each appointment you'll dress in a hospital gown or robe and enter the radiation treatment room. After settling you into position on a table or other flat surface, the radiation therapist will leave the room (just as an X-ray technician does when you're having an X-ray at the dentist or hospital). Then a large machine called a simulator will deliver the exact amount of radiation necessary to kill the cancer cells in the area, which has usually been outlined with ink or a faint tattoo.

It usually takes only a few minutes for a teen to receive the daily dose of radiation. While the simulator is on, you'll have to lie very still so the radiation is directed to the right place on your body.

Sometimes external radiation therapy can be given while a person is getting cancer surgery; this is called intra-operative radiation therapy. After cancer tissue is removed and the area of the body is still exposed, special radiation equipment can give a dose of radiation before the area is stitched shut. Another treatment, called proton-beam radiation therapy, focuses the radiation on the cancer tissue better, with the goal of causing less harm to the surrounding healthy tissue.

You don't have to worry that you'll glow in the dark after radiation treatment: People who receive external radiation are not radioactive. You'll be able to have normal contact with family and friends after you leave the treatment room.

Common Side Effects of Radiation Therapy

Although radiation therapy is painless, it is powerful, and people who receive it might have some problems during and after treatment. These problems (called side effects) are different from person to person, depending on their age, the type of treatment, and where the cancer is located. For example, some people who have radiation therapy may feel more tired than usual, not feel hungry, or lose their hair.

Some of the more common side effects of radiation therapy include:

Depending on how old someone is during radiation therapy, there may be some long-term side effects. Some people may notice they're not growing as fast as their friends. This happens because normal tissues, especially areas that are still growing, might be damaged during radiation treatments.

Teens who receive radiation to the pelvic or abdominal region might have problems having children later in life, although doctors do everything they can to prevent this. Some people who have had radiation therapy can be more likely to develop a second cancer later in life. Anyone who has been successfully treated for cancer should be extra careful to have regular checkups and avoid smoking and sun exposure.

It's important to tell a nurse or doctor about any side effects so they can help treat the problem. If you're receiving radiation therapy as a cancer treatment, your doctors will work to cure you, but they'll also want you to be as comfortable as possible while you're being treated.

What to Expect After Radiation Treatment

Although radiation therapy itself doesn't hurt, it can be scary to think about. You might want to ask your doctor about taking a tour of the hospital or radiation treatment center. Meeting the radiation technologists who will be helping you every day and seeing the radiation equipment may help you feel more comfortable during treatment. Many hospitals set up routine treatment planning visits to prepare patients for treatment. These include a tour of the facilities and a chance to ask questions.

In a lot of hospitals, you can talk to a parent or the radiation therapist on an intercom during external radiation treatment. Someone will always be watching you during treatment, and the machine can be stopped at any time if there's a problem. Some treatment centers even provide closed-circuit TVs so your parent can watch you during the procedure.

As you go through radiation treatment, you may feel like you're all alone — but you're not. Your parent, friends, doctors, nurses, psychiatrists, psychologists, social workers, and other members of the cancer treatment team are there to reassure you before, during, and after radiation therapy.

Friends make you feel good when you're healthy — so surrounding yourself with your buds when you're sick is sure to be a pick-me-up. If you're too tired to head to the mall after school, plan a video-fest at your place instead. Sometimes people worry that their friends will feel weird or uncomfortable around them. Ask a parent, nurse, or counselor for tips on how to help with this situation.

Many camps, support groups, and other activities are available to teens with cancer. Your nurse or hospital social worker can help you find these. Who knows? Your treatment for cancer might lead you to a lifelong friend.

Besides coping with the many emotions you'll feel, you have to deal with the physical stuff, too. Try these tips for chilling out more comfortably during treatment:

Once you're done radiation treatment, it's still important to visit the doctor for follow-up appointments. During these checkups, the doctor will want to know how you're feeling, whether you're having any continuing side effects, and whether there are any signs of the cancer coming back.

Undergoing treatment for cancer can be time-consuming, scary, and sometimes painful — both for the teens going through it and their friends and families. The good news is that radiation therapy can be an effective cancer fighter that lets many people to go on to live healthy, full lives.

Date reviewed: July 2014

Note: All information on TeensHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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