Radiation therapy involves the use of high-energy x-rays and other types of radiation to kill rapidly dividing cancer cells. Radiation damages the DNA of cancer cells, so they are not able to grow or divide.¹

Radiation therapy can be used to:²

• Shrink the tumor before surgery
• Keep the tumor from returning after surgery
• Eliminate cancer cells in other parts of the body
• Relieve cancer symptoms, such as pain

The two primary types of radiation used to treat cancer are:²

• External beam radiation, which directs radiation from a source outside the body
• Internal radiation or brachytherapy, in which a radioactive source is placed inside the body near the cancer site.

Common short-term side effects of radiation therapy, which typically begin 2 to 3 weeks after the start of treatment and usually stop several weeks after treatment is completed, include:³

• Mild skin reactions (like a sunburn)
• Fatigue
• Loss of appetite

Longer-term side effects, which do not appear for several months or years after treatment, include:^2,3

• Risk of a second cancer
• Infertility
• Impotence

In addition to radiation therapy, chemotherapy is another way to treat cancer. Learn more about treating cancer with chemotherapy.

Understanding Cancer – Chemotherapy Side Effects – Treating Cancer in Other Ways
Tracking Your Test Results – Understanding Insurance and Tax Issues
Chemotherapy Resources and Organizations – Register for Programs