Side Effects of Brachytherapy

Last Modified: May 29, 2008


Dear OncoLink "Ask The Experts,"

I would like to know the side effects of brachytherapy for prostate cancer, particularly long term.


Richard Whittington, MD, Associate Professor of Radiation Oncology at the University of Pennsylvania School of Medicine, responds:

The tissue changes from brachytherapy are not that different from what you see with external beam radiation. The secretory activity falls and there is frequent obstruction of the vas deferens/ejaculatory duct. There is “dropout” of the normal glands within the prostate, which are then replaced by dense fibrosis, or scar tissue. What this all means is that most men will have a dry ejaculate. A biopsy will show fibrous tissue with islands of glandular tissue.

On the whole, the effects are very operator- and definition- dependent. The more skill and experience the brachytherapist has, the fewer and less severe the side effects will generally be.

Most report a risk of impotence that is anywhere from 20% to 50%, depending on how rigid a definition you use. Are men taking sildenafil considered potent? Is a partial erection that does not last long enough for intercourse considered potent? Patients should ask the provider exactly how they define the term potent.

The risk of rectal bleeding is about 10%, and the risk of rectal ulcer is <3%. Most men find that their AUA urinary symptom scores rise by about 2 or 3 points. About 5% of men can have telangiectasis (small dilated blood vessels) of the bladder neck causing some hematuria (blood in the urine) with UTI or heavy lifting, etc.