Radiation therapy (sometimes called radiotherapy, x-ray therapy, or irradiation) is the treatment of disease using penetrating beams of high energy waves or streams of particles called radiation. Many years ago doctors learned how to use this energy to “see” inside the body and find disease. You’ve probably seen a chest x-ray or x-ray pictures of your teeth or your bones. At high doses (many times those used for x-ray exams) radiation is used to treat cancer and other illnesses. The radiation used for cancer treatment comes from special machines or from radioactive substances. Radiation therapy equipment aims specific amounts of the radiation at tumors or areas of the body where there is disease.
- Some quick facts about radiation treatment:
- Radiation treatments are painless.
- External radiation treatment does not make you radioactive.
- Treatments are usually scheduled every day except Saturday and Sunday.
- You need to allow 30 minutes for each treatment session although the treatment itself takes only a few minutes.
- It’s important to get plenty of rest and to eat a well-balanced diet during the course of your radiation therapy.
- Skin in the treated area may become sensitive and easily irritated.
- Side effects of radiation treatment are usually temporary and they vary depending on the area of the body that is being treated.
Radiation in high doses kills cells or keeps them from growing and dividing. Because cancer cells grow and divide more rapidly than most of the normal cells around them, radiation therapy can successfully treat many kinds of cancer. Normal cells are also affected by radiation but, unlike cancer cells, most of them recover from the effects of radiation.
To protect normal cells, doctors carefully limit the doses of radiation and spread the treatment out over time. They also shield as much normal tissue as possible while they aim the radiation at the site of the cancer.
The goal of radiation therapy is to kill the cancer cells with as little risk as possible to normal cells. Radiation therapy can be used to treat many kinds of cancer in almost any part of the body. In fact, more than half of all people with cancer are treated with some form of radiation. For many cancer patients, radiation is the only kind of treatment they need. Thousands of people who have had radiation therapy alone or in combination with other types of cancer treatment are free of cancer.
Radiation treatment, like surgery, is a local treatment — it affects the cancer cells only in a specific area of the body. Sometimes doctors add radiation therapy to treatments that reach all parts of the body (systemic treatment) such as chemotherapy, or biological therapy to improve treatment results. You may hear your doctor use the term, adjuvant therapy , for a treatment that is added to, and given after, the primary therapy.
Radiation therapy is often used with surgery to treat cancer. Doctors may use radiation before surgery to shrink a tumor. This makes it easier to remove the cancerous tissue and may allow the surgeon to perform less radical surgery.
Radiation therapy may be used after surgery to stop the growth of cancer cells that may remain. Your doctor may choose to use radiation therapy and surgery at the same time. This procedure is known as intraoperative radiation.