Basic Science: Reconstruction
Moderated Poster Session
MP3-9 - The Distribution of paclitaxel in the rabbit urethra after the inflation of a drug-eluting balloon: evidence with clinical implications
Thursday, September 20
4:00 PM - 6:00 PM
Location: Room 243
assistant professor of surgery
Department of Urology, University of Patras, Patras, Greece
Introduction & Objective :
Urethral strictures are a common urological problem which could require complex reconstructive procedures. Urethral dilation represent a frequent practiced invervention associated with high recurrence rates. Drug-coated balloons with cytostatic drugs have been successfully used for the prevention of vascular restenosis after balloon dilation. In an attempt to reduce the restenosis rates of urethral dilation, these balloon could be used in the urethra. Nevertheless, the urothelium is different than the endothelium and these drugs may not be distributed to the outer layers of the urethra. Thus, an experiment was performed evaluating the distribution of paclitaxel (PTX) in the rabbit urethra after the inflation of a PTX coated balloon (PCB).
Eleven rabbits underwent dilation of the posterior urethra with common endoscopic balloons after urethrography. Nine of these rabbits were additionally treated with PCB. The urethras of the 2 control animals were removed along with 3 more dilated with PCB urethras immediately after the dilation. The remaining of the urethras were removed after 24 (n=3) and 48 hours (n=3). The posterior segments of the urethras were evaluated with hematoxulin and eosin staining as well as with immunohistochemistry (IHC) with polyclonal anti-paclitaxel antibody.
The 2 control specimens showed denudation of the urothelium after balloon dilations and no PTX was observed.All specimens from dilated with PCB urethras showed distribution of PTX to all layers of the urethra. The specimens which were immediately removed exhibited denudation of the urothelium without any inflammation. The specimens removed at 24 and 48 hours showed mild acute inflammation.
PTX is distributed to all layers of the rabbit urethra after balloon inflation. Thus, PTX could exert its activity to the smooth muscle cells which are responsible for the production of collagen and restenosis of the urethra.