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Radiation therapy
Source: Colon Cancer Treatment (PDQ®)–Patient Version, National Cancer Institute.
Source updated: May 16, 2025 · Captured 2026-09-09.
Selected source text with whitespace normalised. This Triangle page is not an NCI PDQ summary. Independent clinical review is pending.
Context: Treatment Option Overview / The following types of treatment are used:
Radiation therapy uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. Colon cancer is sometimes treated with two types of radiation therapy used to treat colon cancer:
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External radiation therapy uses a machine outside the body to send radiation toward the area of the body with cancer.
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Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. Internal radiation therapy may be used to treat colon cancer that has spread to the liver.
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Learn more about Radiation Therapy to Treat Cancer and Radiation Therapy Side Effects.
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Preserved source evidence · Independent clinical review pending · Not medical advice