What is radiotherapy used to treat

Your cells normally grow and divide to form new cells. But cancer cells grow and divide faster than most normal cells. Radiation works by making small breaks in the DNA inside cells. These breaks keep cancer cells from growing and dividing and cause them to die. Nearby normal cells can also be affected by radiation, but most recover and go back to working the way they should. While chemotherapy and other treatments that are taken by mouth or injection usually expose the whole body to cancer-fighting drugs, radiation therapy is usually a local treatment.

Radiation treatments are planned so that they damage cancer cells with as little harm as possible to nearby healthy cells. Some radiation treatments systemic radiation therapy use radioactive substances that are given in a vein or by mouth. More than half of people with cancer get radiation therapy. Sometimes, radiation therapy is the only cancer treatment needed and sometimes it's used with other types of treatment.

The decision to use radiation therapy depends on the type and stage of cancer, and other health problems a patient might have. Still, radiation therapy can be used to treat many types of cancer either alone or in combination with other treatments. While it's important to remember each cancer and each person is different, radiation is often the treatment of choice for the following purposes.

Some cancers are very sensitive to radiation. Radiation may be used by itself in these cases to make the cancer shrink or completely go away. In some cases, chemotherapy or other anti-cancer drugs may be given first. For other cancers, radiation may be used before surgery to shrink the tumor this is called pre-operative therapy or neoadjuvant therapy , or after surgery to help keep the cancer from coming back called adjuvant therapy.

For certain cancers that can be cured either by radiation or by surgery, radiation may be the preferred treatment. This is because radiation can cause less damage and the part of the body involved may be more likely to work the way it should after treatment. For some types of cancer, radiation and chemotherapy or other types of anti-cancer drugs might be used together.

Certain drugs called radiosensitizers help radiation work better by making cancer cells more sensitive to radiation. Cancer Genomics Research. Research on Causes of Cancer. Cancer Prevention Research. Cancer Treatment Research. Cancer Health Disparities. Childhood Cancers Research. Global Cancer Research. Cancer Research Infrastructure. Clinical Trials. Frederick National Laboratory for Cancer Research. Bioinformatics, Big Data, and Cancer.

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This content does not have an English version. This content does not have an Arabic version. Overview Radiation therapy Open pop-up dialog box Close. Radiation therapy External beam radiation uses high-powered beams of energy to kill cancer cells. Request an Appointment at Mayo Clinic. External beam radiation therapy Open pop-up dialog box Close.

External beam radiation therapy During external beam radiation therapy, you're positioned on a table and a large machine moves around you sending beams of radiation into precise points in your body. Share on: Facebook Twitter. Show references Radiation therapy and you: Support for people with cancer. National Cancer Institute.

Accessed April 2, External beam therapy EBT. Gunderson LL, et al. Intensity-modulated and image-guided radiation therapy. In: Clinical Radiation Oncology. Philadelphia, Pa.

Accessed Jan. Riggin ER. Allscripts EPSi.