Treating cancer with radiation

Radiation plays an important role in treating many types of cancers. The use of radiation varies by cancer type, stage and situation. The goals of radiation for treatment include one or more of the following:

• Adjuvant radiation is given to patients with early-stage disease after surgery to remove the tumor, when there is no longer evidence of disease. Adjuvant radiation is used to destroy any undetected cancer cells that may still remain in the surrounding area, after the cancer has been removed.
• Radiation may be used to treat people with advanced cancer to shrink tumors, reduce symptoms and decrease further spread of the cancer. 

Different types of radiation therapy are used to treat cancer:

• External-beam radiation therapy (EBRT) aims radiation beams produced by a machine from outside the body at the tumor to kill cancer cells. This treatment can be used to treat localized cancers or help relieve symptoms if the cancer has spread.
• Brachytherapy is a type of internal radiation. It involves surgery to implant radioactive seeds to kill the cancer. Brachytherapy is used most frequently to treat prostate and breast cancer after surgery. Because the radioactive material is implanted in their body, people undergoing brachytherapy, must take special precautions to minimize exposing other people to radiation.  

You can read more about the role of radiation for different cancers in our section on Treatment by Cancer Type. Like all cancer treatments, radiation can have side effects. Visit our section on Side Effects for more information.