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Why is radiation therapy sometimes given after cancer surgery?
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radiation therapy
External beam radiation therapy (also known as external beam teletherapy, or long-distance therapy) being delivered using a machine known as a linear accelerator.
Radiation therapy is often combined with surgery because the two treatments complement each other's limitations in managing cancer. While surgery is highly effective at removing a localized tumor, it may fail to eliminate cancer cells that have spread beyond the surgical margins.
Conversely, radiation therapy is particularly effective at eradicating undetected disease at the periphery of a tumor, though it is less effective at killing cells located at the center of large tumor masses. By using radiation after surgery—such as following a lumpectomy for breast cancer—the strengths of one treatment offset the weaknesses of the other, providing a more comprehensive approach to destroying cancer cells through genetic damage or apoptosis.1