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"How do chemotherapy and radiation differ?"

ZocdocAnswersHow do chemotherapy and radiation differ?


My mother is getting chemotherapy for a pancreatic tumor, and recently the doctor started talking about using radiation therapy too. But I thought these were the same thing. What's the difference, and when are they each used?


Cancer treatment often contains one or more of 3 possible treatments, surgery, chemotherapy and radiation therapy. Chemotherapy and radiation therapy are two different methods. Chemotherapy is a generic term to describe a group of medications that act to stop or at least slow down the growth of tumor cells. In some cases chemotherapy is able to induce cancer cell death. It is used when the physician wants to fight cancer that could be anywhere in the body because it travels through the blood stream to reach the cancer. The downside to chemotherapy is that it comes into contact with normal tissue resulting in the unwanted side effects (examples: nausea and hair loss). Radiation therapy uses a beam of high energy radiation that targets the tumor while leaving the surrounding tissue less effected. Radiation acts to destroy DNA which can kill the cancer cells. While these two modes of treatment are not necessarily curative with a pancreatic tumor, they will work better together than by themselves. I suggest that you attend your mother's next appointment with her oncologist (if she is okay with that). This will give you a chance to ask these types of questions as well as questions dealing with the reasonable benefits and risks of the combination of this therapy.

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