Radiation therapy affects normal cells as well as cancer cells. Thus the side effects of radiation depend on the amount and the type of radiation you get. Be sure to let your doctor know of any side effects you have.
Here’s an overview of how you might feel during or after having EBRT:
You may have diarrhea, with or without blood in the stool. You may also have cramping or feel like you need to have a bowel movement. If you have these effects, they are likely to begin to occur in the second or third week of treatment.
The skin around the area treated may get irritated, especially under the scrotum or folds of the buttocks. The skin may be red, flake, or drain fluid.
You may lose your pubic hair. Some of it may grow back.
You may feel like you have to urinate often or all the time. Or you may have a burning feeling when you’re urinating. You also may have blood in your urine. If you have these kinds of problems, they usually start to occur about three to five weeks into your radiation treatment.
You may feel very tired, called fatigue, until about a month after your treatment is done.
You may have swelling in your legs, penis, or scrotum. This is rare but occurs more often in men who have also had a lymph node biopsy.
The following effects may continue after EBRT ends. Or they may not appear until months or years after EBRT ends:
Bowel problems, such as diarrhea or cramping
Urinary problems, such as needing to go to the bathroom more often or having trouble controlling your urine
Inability to have an erection called erectile dysfunction
Talk with your doctor about ways to deal with these longer-lasting side effects.
As follow-up to external radiation, you will have your prostate specific antigen (PSA) level checked on a regular basis. The PSA level should go down gradually over time, and may take as long as a couple of years to reach its lowest level. It is not likely to become completely undetectable, even if treatment is successful, because some normal prostate cells will still remain in the body making PSA.