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Radiation Therapy

Radiation therapy (also called radiotherapy) is a cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors. At low doses, radiation is used in x-rays to see inside your body, as with x-rays of your teeth or broken bones.

How Radiation Therapy Works against Cancer

At high doses, radiation kills cancer cells or slows their growth. Radiation therapy is used to:

  • Treat cancer
    Radiation can be used to cure cancer, to prevent it from returning, or to stop or slow its growth.
  • Ease cancer symptoms
    Radiation may be used to shrink a tumor to treat pain and other problems caused by the tumor. Or, it can lessen problems that may be caused by a growing tumor, such as trouble breathing or loss of bowel and bladder control.

Radiation therapy does not kill cancer cells right away. It takes days or weeks of treatment before cancer cells start to die. Then, cancer cells keep dying for weeks or months after radiation therapy ends.

Types of Radiation Therapy

There are two main types of radiation therapy, external beam and internal.

External Beam Radiation Therapy

External beam radiation therapy comes from a machine that aims radiation at your cancer. The machine is large and may be noisy. It does not touch you, but can move around you, sending radiation to a part of your body from many directions.

External beam radiation therapy treats a specific part of your body. For example, if you have cancer in your lung, you will have radiation only to your chest, not to your whole body.

Internal Radiation Therapy

Internal radiation therapy is a treatment in which a source of radiation is put inside your body. The radiation source can be solid or liquid.

Internal radiation therapy with a solid source is called brachytherapy. In this type of treatment, radiation in the form of seeds, ribbons, or capsules is placed in your body in or near the cancer.

You receive liquid radiation through an IV line. Liquid radiation travels throughout your body, seeking out and killing cancer cells.

See Radiation Therapy for Cancer for more information about external beam radiation therapy and internal radiation therapy.

Who Receives Radiation Therapy

External beam radiation therapy is used to treat many types of cancer. For some people, radiation may be the only treatment you need. But, most often, you will have radiation therapy and other cancer treatments, such as surgery and chemotherapy.

Brachytherapy is used to treat cancers of the head and neck, breast, cervix, prostate, and eye.

Liquid forms of internal radiation are most often used to treat thyroid cancer.

How Radiation Is Used with Other Cancer Treatments

Radiation may be given before, during, or after surgery. Doctors may use radiation:

  • Before surgery, to shrink the size of the cancer.
  • During surgery, so that it goes straight to the cancer without passing through the skin. Radiation therapy used this way is called intraoperative radiation.
  • After surgery, to kill any cancer cells that may remain.

Radiation may also be given before, during, or after other cancer treatments to shrink the cancer or to kill any cancer cells that might remain.

Radiation Therapy Can Cause Side Effects

Radiation not only kills or slows the growth of cancer cells, it can also affect nearby healthy cells. Damage to healthy cells can cause side effects. External radiation and brachytherapy cause side effects only in the part of the body being treated.

The most common side effect of radiation therapy is fatigue, which is feeling exhausted and worn out. Fatigue can happen all at once or little by little. People feel fatigue in different ways. You may feel more or less fatigue than someone else who is also getting radiation therapy.

You can prepare for fatigue by:

  • Asking someone to drive you to and from radiation therapy
  • Planning time to rest
  • Asking for help with meals and childcare

See the side effects section to learn more about fatigue and other side effects caused by radiation therapy.

Healthy cells that are damaged during radiation treatment almost always recover after it is over. But sometimes people may have side effects that are severe or do not improve. Other side effects may show up months or years after radiation therapy is over. These are called late effects.

Doctors try to protect healthy cells during treatment by:

  • Using as low a dose of radiation as possible
    The radiation dose is balanced between being high enough to kill cancer cells, yet low enough to limit damage to healthy cells.
  • Spreading out treatment over time
    You may get radiation therapy once a day, or in smaller doses twice a day for several weeks. Spreading out the radiation dose allows normal cells to recover while cancer cells die.
  • Aiming radiation at a precise part of your body
    With external radiation therapy, for example, your doctor is able to aim high doses of radiation at your cancer while reducing the amount of radiation that reaches nearby healthy tissue. These treatments use a computer to deliver precise radiation doses to a tumor or to specific areas within the tumor. To learn more about specific methods of radiation therapy, see Radiation Therapy for Cancer.

How Much Radiation Therapy Costs

Radiation therapy can be expensive. It uses complex machines and involves the services of many health care providers. The exact cost of your radiation therapy depends on the cost of health care where you live, what kind of radiation therapy you get, and how many treatments you need.

Talk with your health insurance company about what services it will pay for. Most insurance plans pay for radiation therapy. To learn more, talk with the business office at the clinic or hospital where you go for treatment. If you need financial assistance, there are organizations that may be able to help. To find such organizations, go to the National Cancer Institute database, >Organizations that Offer Support Services and search for "financial assistance." Or call toll-free 1-800-4-CANCER (1-800-422-6237) to ask for information on organizations that may help.

What to Expect When Having External Beam Radiation Therapy

How Often Will You Have Treatment

Most people have external beam radiation therapy with the same dose of radiation once a day, 5 days a week, Monday through Friday. Treatment lasts up to 6 weeks, depending on the type of cancer you have and the treatment goal. This span of time is called a course of treatment.

Sometimes, the radiation dose or schedule is changed to reach the total dose of radiation more quickly. This can be done in one of these ways:

  • Accelerated fractionation, which gives the half of the usual daily dose of radiation twice each day.
  • Hyperfractionation, which is a smaller than usual daily dose of radiation given twice each day.
  • Hypofractionation, which is a larger than usual daily dose of radiation given once a day for up to 3 weeks.

The doctor may prescribe one of these treatment schedules if he or she feels that it will work better for the type of cancer you have.

Where You Go for Treatment

Most of the time, you will get external beam radiation therapy as an outpatient. This means that you will have treatment at a clinic or radiation therapy center and will not stay the night in the hospital.

What Happens before Your First Treatment

You will have a 1- to 2-hour meeting with your doctor or nurse before you begin radiation therapy. At this time, you will have a physical exam, talk about your medical history, and maybe have imaging tests. Your doctor or nurse will discuss external beam radiation therapy, its benefits and side effects, and ways you can care for yourself during and after treatment. You can then choose whether to have external beam radiation therapy.

If you decide to have external beam radiation therapy, you will be scheduled for a treatment planning session called a simulation. At this time:

  • A radiation oncologist (a doctor who specializes in using radiation to treat cancer) and radiation therapist will figure out your treatment area. You may also hear the treatment area referred to as the treatment port or treatment field. These terms refer to the places in your body that will get radiation. You will be asked to lie very still while x-rays or scans are taken.
  • The radiation therapist will tattoo or draw small dots of colored ink on your skin to mark the treatment area. These dots will be needed throughout your course of radiation therapy. The radiation therapist will use them to make sure you are in exactly the same position for every treatment. The dots are about the size of a freckle. If the dots are tattooed, they will remain on your skin for the rest of your life. Ink markings will fade over time. Be careful not to remove them and tell the radiation therapist if they have faded or lost color.
  • A body mold may be made of the part of the body that is being treated. This is a plastic or plaster form that keeps you from moving during treatment. It also helps make sure that you are in exactly the same position for each treatment
  • If you are getting radiation to the head and neck area you may be fitted for a mask. The mask has many air holes. It attaches to the table where you will lie for your treatments. The mask helps keep your head from moving so that you are in exactly the same position for each treatment.

What to Wear for Your Treatments

Wear clothes that are comfortable and made of soft fabric, such as fleece or cotton. Choose clothes that are easy to take off, since you may need to expose the treatment area or change into a hospital gown. Do not wear clothes that are tight, such as close-fitting collars or waistbands, near your treatment area. Also, do not wear jewelry, adhesive bandages, or powder in the treatment area.

What Happens during a Treatment Session

  • You may be asked to change into a hospital gown or robe.
  • You will go to the treatment room where you will receive radiation. The temperature in this room will be very cool.
  • Depending on where your cancer is, you will either lie down on a treatment table or sit in a special chair. The radiation therapist will use the dots on your skin and body mold or face mask, if you have one, to help you get into the right position.
  • You may see colored lights pointed at your skin marks. These lights are harmless and help the therapist position you for treatment.
  • You will need to stay very still so the radiation goes to the exact same place each time. You will get radiation for 1 to 5 minutes. During this time, you can breathe normally.

The radiation therapist will leave the room just before your treatment begins. He or she will go to a nearby room to control the radiation machine. The therapist watches you on a TV screen or through a window and talks with you through a speaker in the treatment room. Make sure to tell the therapist if you feel sick or are uncomfortable. He or she can stop the radiation machine at any time. You will hear the radiation machine and see it moving around, but you won’t be able to feel, hear, see, or smell the radiation.

Most visits last from 30 minutes to an hour, with most of that time spent helping you get into the correct position.

How to Relax for Treatment Sessions

Keep yourself busy while you wait:

  • Read a book or magazine.
  • Work on crossword puzzles or needlework.
  • Use headphones to listen to music or recorded books.
  • Meditate, breathe deeply, pray, use imagery, or find other ways to relax.

External Beam Radiation Therapy Will Not Make You Radioactive

People often wonder if they will be radioactive when they are having treatment with radiation. External beam radiation therapy will not make you radioactive. You may safely be around other people, even pregnant women, babies, and young children.

What to Expect When Having Internal Radiation Therapy

What Happens before Your First Treatment

You will have a 1- to 2-hour meeting with your doctor or nurse to plan your treatment before you begin internal radiation therapy. At this time, you will have a physical exam, talk about your medical history, and maybe have imaging tests. Your doctor will discuss the type of internal radiation therapy that is best for you, its benefits and side effects, and ways you can care for yourself during and after treatment. You can then decide whether to have internal radiation therapy.

How Brachytherapy Is Put in Place

Most brachytherapy is put in place through a catheter, which is a small, stretchy tube. Sometimes, brachytherapy is put in place through a larger device called an applicator. The way the brachytherapy is put in place depends on your type of cancer. Your doctor will place the catheter or applicator into your body before you begin treatment.

Once the catheter or applicator is in place, the radiation source is placed inside it. The radiation source may be kept in place for a few minutes, for many days, or for the rest of your life. How long it remains in place depends on the type of radiation source, your type of cancer, where the cancer is in your body, your health, and other cancer treatments you have had.

Types of Brachytherapy

There are three types of brachytherapy:

  • Low-dose rate (LDR) implants
    In this type of brachytherapy, the radiation source stays in place for 1 to 7 days. You are likely to be in the hospital during this time. Once your treatment is finished, your doctor will remove the radiation source and the catheter or applicator.
  • High-dose rate (HDR) implants
    In this type of brachytherapy, the radiation source is left in place for just 10 to 20 minutes at a time and then taken out. You may have treatment twice a day for 2 to 5 days or once a week for 2 to 5 weeks. The schedule depends on your type of cancer. During the course of treatment, your catheter or applicator may stay in place, or it may be put in place before each treatment. You may be in the hospital during this time, or you may make daily trips to the hospital to have the radiation source put in place. As with LDR implants, your doctor will remove the catheter or applicator once you have finished treatment.
  • Permanent implants
    After the radiation source is put in place, the catheter is removed. The implants remain in your body for the rest of your life, but the radiation gets weaker each day. As time goes on, almost all the radiation will go away. When the radiation is first put in place, you may need to limit your time around other people and take other safety measures. Be extra careful not to spend time with children or pregnant women.

Internal Radiation Therapy Makes You Give Off Radiation

With liquid radiation, your body fluids (urine, sweat, and saliva) will give off radiation for a while. With brachytherapy, your body fluids will not give off radiation, but the radiation source in your body will. If the radiation you receive is a very high dose, you may need to follow some safety measures. These measures may include:

  • Staying in a private hospital room to protect others from radiation coming from your body
  • Being treated quickly by nurses and other hospital staff. They will provide all the care you need, but may stand at a distance, talk with you from the doorway of your room, and wear protective clothing.

Your visitors will also need to follow safety measures, which may include:

  • Not being allowed to visit when the radiation is first put in
  • Needing to check with the hospital staff before they go to your room
  • Standing by the doorway rather than going into your hospital room
  • Keeping visits short (30 minutes or less each day). The length of visits depends on the type of radiation being used and the part of your body being treated.
  • Not having visits from pregnant women and children younger than a year old

You may also need to follow safety measures once you leave the hospital, such as not spending much time with other people. Your doctor or nurse will talk with you about any safety measures you should follow when you go home.

What to Expect When the Catheter Is Removed

Once you finish treatment with LDR or HDR implants, the catheter will be removed. Here are some things to expect:

  • You will get medicine for pain before the catheter or applicator is removed.
  • The area where the catheter or applicator was might be tender for a few months.
  • There is no radiation in your body after the catheter or applicator is removed. It is safe for people to be near you—even young children and pregnant women.

For a week or two, you may need to limit activities that take a lot of effort. Ask your doctor what kinds of activities are safe for you and which ones you should avoid.

Special Diet Needs

Radiation can cause side effects that make it hard to eat, such as nausea, mouth sores, and throat problems called esophagitis. Since your body uses a lot of energy to heal during radiation therapy, it is important that you eat enough calories and protein to maintain your weight during treatment.

If you are having trouble eating and maintaining your weight, talk to your doctor or nurse. You might also find it helpful to speak with a dietitian. For more information about coping with eating problems see the booklet Eating Hints or the section on side effects.

Working during Radiation Therapy

Some people are able to work full-time during radiation therapy. Others can work only part-time or not at all. How much you are able to work depends on how you feel. Ask your doctor or nurse what you may expect from the treatment you will have.

You are likely to feel well enough to work when you first start your radiation treatments. As time goes on, do not be surprised if you are more tired, have less energy, or feel weak. Once you have finished treatment, it may take just a few weeks for you to feel better—or it could take months.

You may get to a point during your radiation therapy when you feel too sick to work. Talk with your employer to find out if you can go on medical leave. Check that your health insurance will pay for treatment while you are on medical leave.

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