Understanding Radiation Therapy

Understanding Radiation Therapy

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Understanding Radiation Therapy

Radiation therapy can help you in your fight against cancer. Radiation therapy uses high-energy X-rays to kill cancer cells.

What Is Cancer?

Cells in the body start out normal, growing and dividing the way they should. When normal cells change into cancer cells, they begin to grow and divide uncontrollably. A group of cancer cells is called a cancer tumor.

Image showing a normal cell and a cancer cell.

Image showing a damaged normal cell and a dying cancer cell.

How Radiation Therapy Works

Radiation destroys cancer cells gradually, over time. The goal of therapy is to focus on and kill as many cancer cells as possible. Radiation can also damage or kill some of the normal cells that are closest to the tumor. Damaged normal cells can repair themselves, often within a day or so.

Image showing a how radiation therapy works.

Image showing a how radiation therapy works.

External Radiation

Man receiving external radiation.

With external radiation, a machine directs beams of high-energy X-rays at the tumor. The goal of treatment is to kill all of the cancer cells, while affecting few normal cells. The machine can change position so the X-ray beams can enter your body from any angle.

Internal Radiation (Brachytherapy)

With internal radiation, one or more implants are placed in or around the cancer tumor. The implants put the radiation as close to the cancer as possible. Implants can be temporary or permanent.