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External Beam Radiation Therapy for Prostate Cancer

What is external beam radiation therapy for prostate cancer?

  • External beam radiation therapy for prostate cancer is treatment using radiation to kill cancer cells in your prostate. The prostate is a male sex gland that helps make semen. It wraps around your urethra and the bottom of your bladder. The urethra is a tube that carries urine from your bladder to the end of your penis. With prostate cancer, tumor cells turn to cancer, and divide without control or order. These cancer cells often grow, and spread to nearby areas of your body.

  • Radiation is a very strong beam of x-ray energy. External beam radiation therapy stops tumors from growing, and makes them smaller. Tumors may go away completely after this treatment. It may also stop the tumor from spreading to other parts of your body. This treatment can be used when cancer has spread to vesicles (tubes) that carry semen and pelvic lymph nodes. It can be used with other treatments such as medicines, chemotherapy, and surgery to treat your cancer.

What problems may come with prostate cancer?

With prostate cancer, tumors can grow big very quickly and damage tissues around your prostate. You can lose a lot of weight, become very weak, and get tired very easily. You may also have any of the following:

  • Leg swelling: Cancer cells that spread to your lymph glands and vessels can block the flow of lymph. Lymph is the fluid that carries antibodies through your body to fight germs and infection. When vessels are blocked, lymph builds up and may cause swelling and leg pain.
  • Metastasis: Cancer cells can break off from your prostate tumor and spread to other parts of your body. These can reach your bones and organs and grow into new tumors. You can have severe (very bad) pain in your bones, and your bone marrow may stop working. Bone marrow is the spongy part inside your bones that makes blood cells. If your bone marrow stops working, you will get tired more easily, and have a higher risk of getting infections.
  • Sexual problems: The tumor can damage nerves near your penis and stop you from getting an erection. Cancer can also spread to the vessels that carry semen. You may have trouble getting your female partner pregnant.
  • Problems with urination: The tumor can push on your urethra and decrease or block the flow of your urine. Your urine may come out as drops instead of the usual stream of urine. You may have the urge to pass urine more than usual, or feel pain when you pass urine. You may have trouble emptying your bladder completely and feel that some urine is still left inside. Urine may leak out when you do not expect it, such as when you cough or while you sleep. This increases your risk of getting infections, which can lead to kidney damage.

How is external beam radiation therapy given?

  • You will need to wear a hospital gown for the treatment, and you may need to have a full bladder. This will help push away the tissues around your prostate so that the radiation beam can point directly at your tumor. You are taken to a room where the treatment will be given. Caregivers will have you lie down on a special table that can be moved to different positions. The table is moved into the treatment area. A CT scan or ultrasound may be used to mark the location and shape of your tumor. This helps caregivers set and point the beam right at the tumor. A machine is used to make the x-ray beam. A low energy or high energy beam may be used.
  • Dye may be given so that caregivers can see your prostate gland clearly. When you are in the right position, pillows or supports will be used to hold you in place. You will be asked to lie still during the treatment. Your treatment will last for a short time, and should not be painful. After the treatment, you may be able to go home. Treatments are done every day, and you may need them for up to eight weeks. A wide energy beam may be used to treat the whole prostate gland. It can also be used when there is a high risk for cancer to spread to nearby areas in your body.

What are the risks of having external beam radiation therapy?

Watch for changes in your health while you are having treatments, and tell your caregiver about any changes that you see or feel. Your caregiver may give you medicines or other treatments for the following side effects:

  • The following problems may appear soon after your treatments:
    • Blood clot in your leg.
    • Blood in your urine.
    • Dry, red, or broken skin. This makes it easier for you to get infections.
    • Loose watery stools, or blood in your stools.
    • Swelling in your bladder. This may make it hard to empty out all of your urine when you urinate.
    • Trouble sleeping, and feeling very tired.
    • Waking up during the night because you feel like you need to urinate.
  • The following problems may appear months or years after your treatments:
    • Scars (thick patches of healed tissue) may form, and your bladder may get smaller. If this happens, it cannot hold as much urine as it did before, and you may need to urinate more often. Urine may come out when you cough or strain, or before you get to the toilet.
    • New tumors may grow in your body. You may lose a lot of weight and feel very weak.
    • Your urethra may grow scars, and get narrow. If this happens, you may need to strain to let your urine out. Your urine may come out in a weak stream.
    • Swelling or scarring in your bowels. You may have pain in your abdomen (stomach) or blood in your bowel movements.
    • Trouble having an erection or getting your female partner pregnant. You may be given medicines to treat erectile dysfunction (ED). Other treatments such as shots, implants, or vacuum devices may be offered to you. Sexual counseling (talk therapy) may be offered to help you cope with this problem. Ask your caregiver for more information about ED.

How should I care for my skin while getting external radiation therapy?

External beam radiation therapy may make your skin red and very dry. Your skin may also get moist. It may begin to bleed, and start to peel off. Ask your caregiver if you should do the following to care for your skin:

  • Wash your skin gently with mild soap. Do not scrub your skin. Pat yourself dry with a towel instead of rubbing your skin.
  • While bathing, do not soak for a long time as this can make your skin drier.
  • Ask your caregiver what type of lotion or cream would be best for you to use on your skin.

When should I call my caregiver?

Call your caregiver if:

  • You cannot make it to your radiation treatment on time.
  • The skin over the area that was treated is bleeding or peeling off.
  • Your pain is worse after having radiation therapy.
  • You feel sick, are throwing up, or have loose watery bowel movements after your radiation treatment.
  • You have chest pain or trouble breathing that is getting worse over time.

When should I seek immediate help?

Seek care immediately or call 911 if:

  • You have a fever, chills, and body aches after your radiation treatment.
  • You have problems passing urine or bowel movements.
  • You have blood in your urine or bowel movements.
  • You suddenly feel lightheaded and have trouble breathing.
  • You have new and sudden chest pain. You may have more pain when you take deep breaths or cough. You may cough up blood.
  • Your leg feels warm, tender, and painful. It may look swollen and red.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Learn more about External Beam Radiation Therapy for Prostate Cancer

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.