Prostatic artery occlusion: initial findings on pathophysiological response in a canine prostate model

Area of Science:

• Urology
• Interventional Radiology
• Veterinary Medicine

Background:

• Prostatic artery embolization (PAE) is an alternative treatment for benign prostatic hyperplasia (BPH).
• Prostatic artery occlusion (PAO) using Onyx is a modification of PAE, aiming for prostate shrinkage.
• The biological mechanisms underlying PAO's therapeutic effects require clarification.

Purpose of the Study:

• To evaluate the biological mechanisms responsible for the therapeutic effects of PAO in a canine prostate model.
• To assess prostate shrinkage and related biological changes following PAO.

Main Methods:

• Ten adult male beagles underwent PAO with Onyx-18 (n=7) or prostatic artery angiography as control (n=3).
• Serum canine prostate specific esterase (CPSE) and intraprostatic testosterone/dihydrotestosterone (DHT) were measured.
• Prostate volume (PV) was assessed by MRI, and prostates were analyzed histologically for necrosis, fibrosis, and apoptosis.

Main Results:

• PAO led to a significant decrease in serum CPSE and PV from 2 weeks to 6 months post-procedure.
• Histopathology revealed hemorrhagic necrosis and inflammation at 2 weeks, progressing to fibrosis and atrophy by 6 months.
• Apoptosis was detected but did not significantly differ between PAO and control groups, suggesting necrosis is the primary mechanism.

Conclusions:

• PAO induces prostate shrinkage primarily through hemorrhagic ischemia leading to necrosis, rather than apoptosis.
• Serum CPSE is a potential biomarker for assessing treatment response to PAO in canine prostates.