One of the methods of treatment for prostate cancer is with radiation therapy. This can be used alone or in combination with hormonal treatment for treating prostate cancer. Radiation is sometimes used after prostate cancer surgery as another option to destroy any remaining cancer cells and to relive pain from metastatic cancer.  Using radiation is most effective when the cancer has not spread beyond the prostate even though it can still be used if the cancer has spread to other nearby tissue. 

Radiation therapy uses high doses of radiation to destroy cancer cells. During the process the radiation damages the genetic material of the cells making it impossible for them to grow.  Normal, healthy tissue can be damaged during radiation but normal cells can generally repair themselves and return to functioning whereas cancer cells cannot.

A bone scan or CT scan is typically done before radiation therapy to make sure the cancer has not spread to other areas of the body. 

Candidates for radiation include:

·Cancer that has not spread in generally healthy men younger than 70.

·Cancer that has not spread to the bones, is not getting better with hormonal treatment, and is causing pain.

·Cancer that has come back in the prostate after surgery

·Cancer cells that may remain after surgery if all the cancer was not able to be removed.

There are two ways radiation is delivered to destroy prostate cancer:

1. External-beam Radiation Therapy

This type uses a large machine aiming a beam of radiation at the tumor. The treatments are usually done 5 days a week for 4 to 8 weeks. If the cancer has spread to the bone or if there are complications from the radiation, shorter periods of treatment may be given to relieve pain.

One type of external-beam radiation is called conformal radiotherapy (3D-CRT). This uses a three-dimensional planning system targeting radiation at the tumor helping to protect healthy tissue from the damaging effects of radiation.

Another type is called intensity-modulated radiation therapy (IMRT). This one uses a more carefully adjusted amount of radiation protecting more tissue than conformal radiotherapy does.

A third type is called proton beam therapy.  Instead of using x-rays, this one uses protons allowing a higher amount of specifically-directed radiation protecting healthy tissue, particularly the rectum. 

2. Brachytherapy also known an Internal Radiation Therapy

This type of radiation uses needles to insert dozens of tiny seeds containing radioactive material through the skin into the prostate. Ultrasound helps the surgeon locate the prostate guiding the needles.  This can be done using either high-dose-rate (HDR) or low-dose-rate (LDR) brachytherapy .

HDR uses radioactive material placed into the prostate for a very brief time period (seconds to minutes) before being removed. This radiation is delivered this way several times.

LDR uses a lower dose of radioactive material that is left in place permanently. 

The decision of where to use radiation therapy or not depends on many factors but with the guidance of your doctor, they can help you determine which course of treatment will result in the best outcome.