A Proof-of-Concept Study on the Use of Prostate Artery Embolization Before Definitive Radiation Therapy in Prostate Cancer

Abstract

Purpose

Prostatic artery embolization (PAE) is an effective therapy for alleviating lower urinary tract symptoms (LUTS) in patients with benign prostatic hyperplasia; however, is not well studied in patients with concurrent prostate cancer (PCa). We demonstrate a proof of concept for PAE before definitive radiation therapy (RT) in patients with PCa.

Methods and Materials

From December 2017 to July 2019, 9 patients with PCa underwent PAE for the indication of LUTS from benign prostatic hyperplasia with concurrent PCa. Five received radiation and all follow-ups at our institution and were therefore included in the analysis. Median follow-up was 18 months from the time of PAE. Side effects during radiation were quantified using the Common Terminology Criteria for Adverse Events scoring system. Pre- and post-PAE plans were compared in the 5 patients by performing an isovolumetric expansion of the post-PAE plan (treated plan) equivalent to the measured volume reduction after PAE. Patient 1 (PT-01) and PT-02 had prostate RT alone whereas PT-03, PT-04, and PT-05 had prostate with elective nodal coverage RT. Mean doses to organs at risk were compared between the 2 plans.

Results

The mean International Prostate Symptom Score reduction after PAE was 13.8 (5.0-30.0; P = .02). The mean prostatic volume reduction after PAE was 23.1% (7.2%-47.7%). There were no Common Terminology Criteria for Adverse Events grade 3 (severe) or higher during radiation. Post-PAE plans in PT-01 and PT-02 had on average 23.2%, 39.8%, and 22.9% decrease in mean dose across the bladder, rectum, and penile bulb, respectively, compared with the pre-PAE plans. There were no appreciable differences in dosimetry in PT03, PT-04, and PT-05 who had nodal coverage. There was no biochemical failure in any of the patients.

Conclusions

We demonstrate a proof of concept that PAE is a clinically significant adjunctive therapy for alleviating LUTS and achieving significant volume reduction before RT, resulting in decreased radiation-related toxicity from RT for PCa.