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.
At high doses, radiation kills cancer cells or slows their growth. Radiation therapy is used to:
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.
There are two main types of radiation therapy, external beam and internal.
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 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.
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.
Radiation may be given before, during, or after surgery. Doctors may use radiation:
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 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:
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:
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.
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:
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.
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.
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:
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.
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.
Keep yourself busy while you wait:
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.
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.
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.
There are three types of brachytherapy:
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:
Your visitors will also need to follow safety measures, which may include:
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.
Once you finish treatment with LDR or HDR implants, the catheter will be removed. Here are some things to expect:
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.
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.
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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