Radiation

Radiation is the use of high-energy radiation from x-rays, gamma rays, neutrons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body, or it may come from radioactive material placed in the body near cancer cells.

High doses of radiation kill cells or keep them from growing and dividing. Because cancer cells grow and divide more rapidly than the normal cells around them, radiation can successfully treat many kinds of cancer. Normal cells are also affected by radiation, but most of them recover from the effects.

To protect normal cells, doctors carefully limit the doses of radiation and spread treatment out over time. They also shield as much normal tissue as possible while they aim the radiation at the site of the cancer.

Additional information about radiation oncology can be found at: http://astro.org/patient/treatment_information/