Prostate biopsy can cause urinary, erectile problems
Wednesday, 1 September 2010- Biopsies taken to diagnose prostate cancer commonly cause temporary erectile dysfunction and, in some cases, lingering urinary problems, according to a new study.
The findings, reported in the Journal of Urology, highlight the fact that even the tests for diagnosing prostate cancer can have side effects.
And men who are undergoing prostate biopsies -- as well as those considering prostate cancer screening -- should be aware of those risks, experts say.
This is especially important for men facing the prospect of multiple biopsies, since the risk of side effects appears to be related to the number of needle sticks used.
For the study, German researchers followed 198 men who had been randomly assigned to undergo one of three forms of biopsy to check for suspected prostate cancer: a standard biopsy, where a needle was used to take no more than 10 tissue samples; a 10-sample biopsy along with the use of a periprostatic nerve block to lessen any pain from the procedure; or a "saturation" biopsy, where 20 tissue samples were taken.
Men who underwent saturation biopsies had the highest risk of developing lingering problems with urination, such as straining to pass urine and frequent nighttime trips to the bathroom.
Of that group, 10% reported severe symptoms before the biopsy; that figure increased to 18% one week after the test, and to 29% 12 weeks afterward.
Men who'd had a standard biopsy showed an increase in urinary symptoms only in the first week. The%age reporting moderate symptoms increased from roughly 32% to 39%, and the proportion with severe symptoms rose from 18% to 20.5%.
Among men who'd had a biopsy with nerve block, just 0.6% reported severe urinary symptoms before the test. That rose to 8% one week afterward, and to almost 17% by week 12 -- though that latter finding was not statistically significant, which means it could have been due to chance.
When it came to erectile function, men in all three biopsy groups had more problems one week after the test. The side effect did, however, gradually decrease over time.
Among men in both the standard biopsy and saturation-biopsy groups, just over half reported severe erectile dysfunction one week after the test -- up from around one-quarter before. In the nerve-block group, that rate rose from 11% to 39%.
By week 12, the men's rates of erectile problems had declined to close to their baseline levels.
The findings are "not unexpected," said Dr. Paul Schellhammer, a urologist at Sentara Health System/Eastern Virginia Medical School in Norfolk, US, who was not involved in the research.
However, he noted in an interview, there has been little study into the urinary and erectile side effects of prostate biopsies.
It is not clear from this study exactly why men undergoing saturation biopsy had a greater risk of longer term urinary symptoms, according to lead researcher Dr. Tobias Klein of Marienhospital Herne in Germany.
The fact that prostate biopsies carry some risks -- which, besides the ones seen in this study, include more-immediate problems like bleeding and infection -- also has implications for men considering prostate cancer screening, according to Schellhammer.
Routine screening with PSA testing is controversial. The tests measure concentrations of prostate-specific antigen, a protein produced by the prostate gland whose blood levels generally rise when a prostate tumor is present; however, a relatively high PSA does not necessarily mean cancer, and a biopsy must be done to confirm. And those biopsies often turn out to be negative.
In the current study, 40% of the men were found to have cancer after their prostate biopsy.
Source: Reuters Health / Journal of Urology, online August 19, 2010.
