Transurethral photodynamic therapy in benign prostatic hyperplasia : a canine pilot study using benzoporphyrin derivative

Photodynamic therapy (PDT) principles were evaluated in management of benign prostatic hyperplasia (BPH) in a canine model. Five dogs were injected with benzoporphyrin derivative (BPD) and samples of prostate, bladder, urethra and rectum were taken at 1, 2, 3 and 4 hours and analyzed for BPD. Next, 16 dogs were treated with 100 Joules at 690 nm light form argon dye laser 1 hour after administration of BPD at 0.5 mg/kg using cylindrical diffuser tip fiber passed transurethrally. The prostates were harvested weekly up to 4 weeks and the size of the lesion was measured and the prostates were examined. Prostate had the highest BPD levels. Hemorrhagic lesion of 2.5 cm in diameter was noted at 1 week after PDT. At 3 and 4 weeks there were changes of glandular atrophy in the periurethral region. Minimally invasive technique of transurethral PDT causes glandular and stromal changes in the periurethral zone and has potential in the treatment of BPH.