Prostate Cancer Treatment Radiation

Radiotherapy uses radiation and x-rays to inhibit or kill cancerous cell growth and prevent the cancer from spreading. Radiotherapy is usually used if the cancer has not spread outside of the prostate. It can prevent further growth or spread of the carcinoma, and may even cure early-stage cancer. Hormone therapy often supplements radiation treatments.

Side Effects of Radiotherapy

Impotence is a possible side effect of radiotherapy, although the risk is generally lower than it is for surgical techniques. Other side effects usually clear up once treatment is stopped, and include:

  • Fatigue
  • Hair loss in the pelvic region (usually temporary, occasionally permanent)
  • Diarrhea
  • Urination difficulties
  • Dry, red skin
  • Rectal irritation
  • Rectal bleeding.

External Beam Radiation Therapy

A beam of x-rays is directed at the cancerous area in small doses over a period of several weeks. The radiation disrupts cellular growth of both the cancerous and healthy surrounding cells. While surrounding cells are also affected by the radiotherapy, healthy cells are more likely to recover from the treatment than cancerous cells.

Conformal Radiation Therapy

Conformal radiation therapy is a more accurate form of external beam treatment. The cancer is pinpointed using MRI, CT scans, or ultrasound. This allows the x-ray beam to be more precisely aimed, limiting damage to surrounding cells.

Proton Beam Therapy

A variation on conformal radiation therapy. Instead of using x-rays to irradiate the cells, protons are used. Protons are positively-charges atomic particles.


Brachytherapy, or radioactive seed implant therapy, delivers radiation directly to the cancer cells. Tiny radioactive “seeds” are implanted directly into the prostate, where they remain active for up to a year. While the cancer cells are irradiated, healthy cells receive minimal exposure.

Brachytherapy has a lower rate of causing impotence than traditional radiotherapy. In some cases white blood cell counts may be lower than normal during treatment.

Thermal Ablation

Thermal ablation is an experimental procedure that uses heat instead of x-rays, to kill cancer cells. In thermal ablation needle electrodes are attached to the tumor through an insulated tube. The heat kills tumor cells, which become scar tissue and eventually shrink.


Another experimental procedure, cryotherapy is the opposite of thermal ablation. Instead of using heat, cryotherapy uses cold to kill tumor cells. The temperatures used in cryotherapy are extremely cold: as low as -190 °C (-310 °F)! Few side effects have been reported, but the procedure is still under study.


Radiological Society of North America, Inc.. (reviewed 2001). Prostate cancer. Retrieved January 24, 2003 from

Wood, B. J.