Botulinum neurotoxin A for benign prostatic hyperplasia.
OBJECTIVE
The injection of botulinum neurotoxin A (BoNT-A) into the prostate represents an alternative, minimal invasive treatment for lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH), which gained the interest of urologists during the last years, although it is not yet licensed. The purpose of this review is to summarize the mechanisms through which BoNT-A could inhibit the progression of BPH and eliminate the lower urinary tract symptoms according to the findings of animal studies. Furthermore, we review clinical studies to report the efficacy and safety of intraprostatic BoNT-A injection according to various injection protocols.


RESULTS
The experimental studies report induced relaxation of the prostate, atrophy, and reduction in its size through inhibition of the trophic effect of the autonomic system on the prostate gland. Also, a possible mechanism of reduction in lower urinary tract symptoms might take place through inhibition of sensory afferents from the prostate to the spinal cord. Clinical studies report symptomatic relief and improvement in the measured parameters during the follow-up period, whereas local or systematic side-effects are rare.


CONCLUSIONS
We should recognize that, at present, this therapy is still experimental. Although the results of the clinical studies are encouraging, the level of evidence is low. Clearly, we need large-scale, clinical, placebo-controlled, randomized studies, including long-term surveillance to document the evidence of this therapy and, eventually, to register BoNT-A for this indication.
Oeconomou
Athanassios
A
Department of Urology, University of Thessalia School of Medicine, Larissa, Greece. thaoik@hotmail.com
Madersbacher
Helmut
H
D000818:Animals; D019274:Botulinum Toxins, Type A / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D009465:Neuromuscular Agents / Q000627:therapeutic use*; D011470:Prostatic Hyperplasia / Q000188:drug therapy*
D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A