04:21 PM Abstract No. 12 Transarterial embolization of prostate with biodegradable flutamide-loaded PLA/PLGA microspheres for benign prostate hyperplasia: preliminary study in a normal swine model

To prospectively evaluate whether transarterial embolization with biodegradable flutamide-loaded PLA/PLGA microspheres with sustained-release properties in the prostate of swine can induce shrinkage in the volume of prostatic tissue. Flutamide is a strong nonsteroidal antiandrogen acts as selective, competitive and silent antagonist. Sustained-release flutamide-loaded polylactide/poly (lactic-co-glycolic acid) (PLA/PLGA) microspheres were successfully fabricated using the single emulsion (o/w) solvent evaporation method in our preliminary study. Twelve male swines were randomly assigned to either the experimental group (n-6) or control group (n-6). Selective angiography was performed to deliver microspheres. In the experimental group, 200–700 micron in diameter flutamide-loaded microspheres were used for embolization.250 mg of total flutamide was used per procedure. 6 weeks later animals euthanized for necropsy, the prostates were removed for size measurement and histopathologic examination. Paired Student t test was used for statistical analysis. All procedures were technically succesful. The mean prostate volume after embolization in the experimental group was significantly (P<0.001) diminished compared with the mean prostate volume for the control group. Microscopic examination showed that normal gland structure was partially replaced by fibrosis and atrophy in the residual gland tissue. Embolization of the prostatic arteries with flutamide-loaded PLA/PLGA microspheres can induce strong shrinkage of the prostate. This study shows that transarterial targeted embolization of prostatic arteries with flutamide-loaded PLA/PLGA microspheres with sustained release properties may provide an effective alternative approach to the treatment for benign prostatic hyperplasia in humans.