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Radiation Therapy for Cancer

Table of Contents

Treatment Overview

Radiation therapy uses high energy rays, such as X-rays, to destroy cancer cells and shrink tumors in different parts of the body. It is used to treat many types of cancer.

Radiation damages the genetic material of cancer cells, which stops their growth. Radiation may also damage normal cells that are close to the cancer cells. But normal cells usually repair themselves, while the cancer cells cannot.

Side effects from radiation therapy are a problem. Usually the side effects are temporary. But some side effects may be permanent. Researchers keep looking for the lowest radiation dose that effectively kills cancer cells. And with new technology, people getting radiation therapy have fewer problems than in the past.

There are two main ways that radiation is done. When it is given from a machine outside the body, it's called external beam radiation, or EBRT. When radiation is placed inside the body, it's called internal radiation, or brachytherapy.

Other types of radiation include:

Radiation therapy may be given before surgery to shrink a tumor, such as with bladder cancer. Or it may be given during surgery or while you are getting chemotherapy. Or it may be given after other treatment, such as after surgery for breast cancer.

Radiation therapy may be given when a person with cancer is not well enough for other treatment, such as surgery. It's also used in palliative care for advanced or metastatic cancer. For example, it can relieve pain by shrinking tumors in the bones.

Why It Is Done

Radiation therapy is used to destroy cancer cells and to shrink tumors.

How Well It Works

Radiation is one of the main treatments used to kill cancer cells. But it doesn't always cure cancer. Researchers continue to study safer and more effective ways to use radiation therapy to treat cancer.

Risks

Radiation therapy may shrink a tumor, give you relief from cancer symptoms, or possibly cure cancer. But it has risks for serious side effects. Your doctor will recommend radiation therapy if the doctor thinks that the benefit you may have from this treatment is greater than the risks.

Risks of radiation therapy during and right after treatment include:

Most of these problems will go away soon after the treatment ends. But sometimes the side effects are permanent, such as when the salivary glands are damaged.

And sometimes side effects may show up months or years after radiation therapy. These can include:

Credits for Radiation Therapy for Cancer

Current as of: October 25, 2023

Author: Healthwise Staff (https://www.healthwise.org/specialpages/legal/abouthw/en)
Clinical Review Board (https://www.healthwise.org/specialpages/legal/abouthw/en)
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The Health Encyclopedia contains general health information. Not all treatments or services described are covered benefits for Kaiser Permanente members or offered as services by Kaiser Permanente. For a list of covered benefits, please refer to your Evidence of Coverage or Summary Plan Description. For recommended treatments, please consult with your health care provider.