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How Radiation Therapy Works

Radiation Therapy (irradiation or radiotherapy) is the use of high energy radiation, primarily x-rays, to kill cancer cells. In high doses, radiation causes damage to cells by interfering with the cell’s ability to grow and reproduce. Cells that are growing and multiplying are very sensitive to the effects of radiation. Because cancer cells reproduce more frequently than normal cells, they are more likely to be damaged by radiation. Normal cells can also be affected by radiation, but normal cells tend to be able to recover from radiation damage.

Learn about the importance of individualized radiation treatment.

When radiation treatments are given for cancer, special care is taken to spare as much normal tissue as possible from radiation exposure. The radiation dose is carefully measured and aimed at the tumor to kill as many cancer cells with as little damage to normal tissue as possible.

Radiation Therapy can be used with surgery, chemotherapy and/or biologic therapy to cure, control or relieve symptoms in patients with cancer.

Two kinds of radiation therapy

    external beam: an external beam radiation therapy machine outside your body aims the radiation at your cancer cells.

    internal or brachytherapy: Sometimes this type of radiation therapy is also called liquid radiation, because the radiation is placed inside your body, near the cancer cells.

Most patients receive external beam radiation.

Radiation Therapy can be used to treat almost any type of cancer, anywhere in the body. Radiation is also used to treat some benign (non-cancerous) conditions. For some patients, radiation therapy will be the only treatment necessary for their cancer, but very often it is done along with surgery and/or chemotherapy.

Radiation Therapy combined with Surgery

When radiation is combined with surgery, the radiation treatments may be given before or after surgery. When it is done before surgery it is used to shrink the size of a tumor to make removal easier. More commonly the radiation treatments are given after surgery to reduce the chance that the cancer will come back, among other reasons.

Radiation Therapy combined with Chemotherapy

Radiation treatments may also be given in combination with chemotherapy treatments, given before, during or after radiation. Chemotherapy is sometimes given weekly, prior to radiation to sensitize the cancer cells to the affects of the radiation.

To schedule an appointment with University of Michigan Radiation Oncology, please call 734-936-4300

Our Location: U-M Department of Radiation Oncology
University Hospital
1500 East Medical Center Drive, Rm. UH B2C490
Ann Arbor, Michigan 48109-5010     |     Map
Please note: The Department of Radiation Oncology is not located in the cancer center building. We have our own entrance and parking area.

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