The relationship of embolic particle size to patient outcomes in prostate artery embolisation for benign prostatic hyperplasia: a systematic review and meta-regression

Prostate artery embolization using n-butyl cyanoacrylate glue for symptomatic benign prostatic hyperplasia: A six-month outcome analysis in 103 patients

PURPOSE

The purpose of this study was to assess the feasibility, safety, and 6-month outcomes of prostate artery embolization (PAE) using N-butyl-cyanoacrylate (NBCA) glue as the only embolic agent in patients with benign prostatic hyperplasia (BPH)-related lower urinary tract symptoms.

MATERIALS AND METHODS

Patients with BPH-related lower urinary tract symptoms who were treated by PAE using methacryloxysulfolane-NBCA mixed with ethiodized oil (1:8 ratio) between September 2018 and January 2023 were retrospectively included. Vascular mapping was made using cone-beam computed tomography angiography. PAEs were performed as an outpatient procedure, under local anaesthesia. Outcomes were assessed at six months using the International Prostate Symptoms Score (IPSS) and associated quality-of-life score (IPSS-QoL), prostate-specific antigen (PSA) level, prostate volume, and International Index of Erectile Function form 5 (IIEF5).

RESULTS

A total of 103 men with a mean age of 68.4 ± 6 (standard deviation [SD]) years were included. Technical success rate was 100%. The mean fluoroscopy time was 26.4 ± 12.5 (SD) min and the median radiation dose was 23 980 mGy·cm (Q1, Q3: 16 770, 38 450). Compared to baseline, statistically significant improvements were observed at six months for the IPSS (8.9 ± 6.2 [SD] vs. 20.2 ± 6.5 [SD]; P = 0.01), IPSS-QoL (2.1 ± 1.4 [SD] vs. 5.1 ± 0.9 [SD]; P = 0.01), PSA level (3.6 ± 3.2 [SD] ng/mL vs. 4.8 ± 4.2 [SD] ng/mL; P = 0.0001), and prostate volume (78.6 ± 43.5 [SD] mL vs. 119.1 ± 65.7 [SD] mL; P = 0.01). Minor adverse events developed in 19/103 (18.4%) patients. No major complications occurred. Compared to baseline, the IIEF5 did not change significantly at six months (15.3 ± 6.8 [SD] vs. 15.8 ± 6.8 [SD]; P = 0.078).

CONCLUSION

PAE with NBCA is a feasible and safe method that provides good outcomes at six months in patients with BPH-related lower urinary tract symptoms. This method deserves further evaluation in randomized trials with longer follow-up.

Comparing prostatic artery embolization to surgical and minimally invasive procedures for the treatment of benign prostatic hyperplasia: a systematic review and meta-analysis

BACKGROUND

To summarize current evidence to report a comparative systematic review and meta-analysis of prostatic artery embolization (PAE) with transurethral resection of the prostate (TURP) and open simple prostatectomy (OSP) for the treatment of benign prostatic hyperplasia (BPH).

METHODS

A systematic literature search was performed to identify studies published from inception until August 2021. The search terms used were (prostate embolization OR prostatic embolization) AND (prostatic hyperplasia OR prostatic obstruction) as well as the abbreviations of PAE and BPH. Risk of bias was assessed using the Cochrane Risk of Bias tool for randomized controlled trials (RCTs) and the Risk of Bias in Non-randomized Studies-of Interventions (ROBINS-I) tool for observational studies. Random-effects meta-analysis was performed using Revman 5.4.

RESULTS

Seven studies were included with 810 patients: five RCTs and one observational study compared PAE with TURP, and one observational study compared PAE with OSP. The included studies had considerable risk of bias concerns. TURP and OSP were associated with more statistically significant improvements in urodynamic measures and BPH symptoms compared to PAE. However, PAE seems to significantly improve erectile dysfunction compared to OSP and improve other outcome measures compared to TURP, although not significantly. PAE appeared to reduce adverse events and report more minor complications compared with TURP and OSP, but it is unclear whether PAE is more effective in the long-term.

CONCLUSION

PAE is an emerging treatment option for patients with symptomatic BPH who cannot undergo surgery or have undergone failed medical therapy. Overall, PAE groups reported fewer adverse events. Future ongoing and longer-term studies are needed to provide better insight into the benefit of PAE compared to other treatment options.

Update on the management of benign prostatic hyperplasia and the role of minimally invasive procedures

Lower urinary tract symptoms due to benign prostatic hyperplasia constitute a substantial burden, affecting the quality of life of those affected by this condition. While watchful waiting and medical management using a wide array of pharmaceuticals can be effective, surgery has been one of the most definite solutions for those highly affected by this condition. Transurethral resection of the prostate (TURP) is the gold standard surgical procedure, but other alternatives using laser (HoLEP and ThuLEP) and robotic water jets (Aquablation) are emerging treatments aimed at reducing postoperative morbidity. Minimally invasive procedures conducted in outpatient settings and under local anesthesia or sedation are increasingly being used, especially in those patients with high surgical risk due to comorbidities. These procedures include prostatic arterial embolization, water vapor thermal therapy (Rezum), prostatic urethral lift (Urolift), temporary implantable nitinol device (TIND/iTIND), and transurethral microwave thermotherapy (TUMT). The evidence supporting these treatments is growing, but some uncertainties remain as to what is the magnitude of their advantages and disadvantages compared to TURP. Innovations in the technologies involved in these new procedures may improve their profile for effectiveness and safety. Moreover, new devices are being investigated for marketing approval. Issues around costs and patients' preferences are also yet to be elucidated, thus their evolving role needs to be weighed against the aforementioned considerations.

Prostate artery embolization on lower urinary tract symptoms related to benign prostatic hyperplasia: A systematic review and meta-analysis

BACKGROUND

Prostate artery embolization (PAE) is a promising minimally invasive therapy that improves lower urinary tract symptoms (LUTS) related to benign prostatic hyperplasia (BPH). Transurethral resection of the prostate (TURP) is the gold standard therapy for LUTS/BPH.

AIM

To evaluate the efficacy and safety of PAE vs TURP on LUTS related to BPH.

METHODS

A literature review was performed to identify all published articles on PAE vs TURP for LUTS/BPH. Sources included PubMed, Embase, Cochrane library databases, and Chinese databases before June 2022. A systematic review and meta-analysis were conducted. Outcome measurements were combined by calculating the mean difference with a 95% confidence interval. Statistical analysis was carried out using Review Manager 5.3.

RESULTS

Eleven studies involving 1070 participants were included. Compared with the TURP group, the PAE group had a similar effect on the International Index of Erectile Function (IPSS) score, Peak urinary flow rate (Qmax), postvoid residual volume (PVR), Prostate volume (PV), prostatic specific antigen (PSA), The International Index of Erectile Function short form (IIEF-5) scores, and erectile dysfunction during 24 mo follow-up. Lower quality of life (QoL) score, lower rate of retrograde ejaculation and shorter hospital stay in the PAE group. There was no participant death in either group. A higher proportion of haematuria, urinary incontinence and urinary stricture was identified in the TURP group.

CONCLUSION

PAE may be an appropriate option for elderly patients, patients who are not candidates for surgery, and patients who do not want to risk the potential adverse effects of TURP. Studies with large cases and long follow-up time are needed to validate results.

Prostatic artery occlusion versus prostatic artery embolisation for the management of benign prostatic hyperplasia: early results in a canine model

OBJECTIVE

To compare the technical efficacy and safety between prostatic artery occlusion (PAO) with ethylene vinyl alcohol copolymer (EVOH) and prostatic artery embolizsation (PAE) with microspheres in a canine model.

METHODS

17 adult male beagles underwent PAO (n = 7) with Onyx-18 or PAE (n = 10) with microspheres (300-500 µm). To evaluate the primary outcomes (technical efficacy and safety), MRI evaluations were performed immediately before and 1 week, 2 weeks, and 1 month after procedures to document prostate volume (PV); and all dogs were inspected for procedure-related complications during 1 month follow-up. The secondary outcomes included the prostate ischaemia size detected by MRI and recanalisation of prostatic artery by follow-up angiography. Differences between groups were statistically analysed.

RESULTS

Both procedures were bilaterally successful in all animals. Compared with PAE, the mean fluoroscopy time (23.80 vs 36.24 min, p = 0.014) and radiation dose (68.19 vs 125.26 mGy, p = 0.003) were significantly less in PAO procedure. The mean percentage of PV change significantly decreased in both groups at 2 weeks (30.71% vs  37.89%) and 1 month (56.41% %vs 55.56%) after PAO and PAE respectively), without significant differences between groups at either time point. No major complications were observed except one animal after PAO with transient haematuria and acute urinary retention. The mean prostate ischaemia induced by PAO was significant greater compared with PAE at 1 week (43.44% vs 18.91%, p=0.001). PAO with EVOH is technically feasible and with comparable efficacy and safety with PAE. There are possible benefits to PAO over PAE.

ADVANCES IN KNOWLEDGE

A new technical modification of the PAE consisting of the use of liquid embolic agent to occlude the prostatic artery trunk and its branches has been developed in pre-clinical study, showing to be an effective and safe procedure which can induce a significant prostate shrinkage for the management of symptomatic benign prostatic hyperplasia in patients. In addition, the findings have showed a similar therapeutic effect comparable with the conventional PAE using microspheres.

Protection of nontarget structures in prostatic artery embolization

Objective

To describe the efficacy and safety of protective embolization during prostatic artery embolization, as well as to discuss its clinical relevance.

Materials and Methods

This was a retrospective, observational, single-center study including 39 patients who underwent prostatic artery embolization to treat lower urinary tract symptoms related to benign prostatic hyperplasia between June 2008 and March 2018. Follow-up evaluations, performed at 3 and 12 months after the procedure, included determination of the International Prostate Symptom Score, a quality of life score, and prostate-specific antigen levels, as well as ultrasound, magnetic resonance imaging, and uroflowmetry.

Results

Protective embolization was performed in 45 arteries: in the middle rectal artery in 19 (42.2%); in the accessory internal pudendal artery in 11 (24.4%); in an internal pudendal artery anastomosis in 10 (22.2%); in the superior vesical artery in four (8.9%); and in the obturator artery in one (2.2%). There was one case of nontarget embolization leading to a penile ulcer, which was attributed to reflux of microspheres to an unprotected artery. There were no complications related to the protected branches. All of the patients showed significant improvement in all of the outcomes studied (p < 0.05), and none reported worsening of sexual function during follow-up.

Conclusion

Protective embolization can reduce nontarget embolization during prostatic artery embolization without affecting the results of the procedure. In addition, no adverse events other than those expected or previously reported were observed. Therefore, protective embolization of pudendal region is safe.

Prostate Artery Embolization Using N-Butyl Cyanoacrylate Glue for Urinary Tract Symptoms Due to Benign Prostatic Hyperplasia: A Valid Alternative to Microparticles?

Our goal was to evaluate the feasibility, safety, and short-term outcomes of prostate artery embolization (PAE) with N-butyl cyanoacrylate (NBCA) glue as the only embolic agent in patients with benign prostatic hyperplasia (BPH)-related lower urinary tract symptoms (LUTSs). A two-center retrospective study of 50 patients (mean age, 67.6 ± 7.4 years; range, 54-85 years) treated with NBCA between 2017 and 2020 was conducted. PAE was performed using a mixture of Glubran 2 glue and Lipiodol in a 1:8 ratio, under local anesthesia, on an outpatient basis, after cone-beam computed tomography vascular mapping. Mean total injected NBCA/Lipiodol volume was 0.9 ± 0.3 mL, total injection time was 21.9 ± 7.8 s, and total radiation dose was 18,458 ± 16,397 mGy·cm. Statistically significant improvements over time occurred for the International Prostate Symptoms Score (9.9 ± 6.8 versus 20.5 ± 6.7, p = 0.0001), quality-of-life score (2.2 ± 1.5 versus 4.9 ± 1.0, p = 0.0001), prostate-specific antigen level (4.6 ± 3.0 versus 6.4 ± 3.7, p = 0.0001), and prostate volume (77.3 ± 30.5 versus 98.3 ± 40.2, p = 0.0001) at a median of 3 months versus baseline. Minor adverse events developed in 11/50 (22%) patients, but no major complications occurred. The International Index of Erectile Function did not change significantly. PAE with NBCA is feasible, safe, fast, and effective for patients with BPH-related LUTSs. Prospective comparative studies with longer follow-ups are warranted.

Using prostate contrast retention (PCR) as the procedural endpoint in prostatic artery embolization for benign prostatic hyperplasia

OBJECTIVES

The failure rate following prostate artery embolization (PAE) is around 20%, which may in part result from inadequate embolization. Prostate contrast retention (PCR) adequacy on immediate post-embolization cone-beam CT may provide better assessment of embolization completeness than arterial contrast stasis seen on fluoroscopy alone. The aim of this study was to evaluate outcomes of PAE using PCR adequacy as the procedural endpoint.

METHODS

A retrospective cohort study of all PAE cases using this technique at a single large volume center was conducted. Following initial embolization of the main prostatic arteries, if PCR was inadequate, additional embolization was performed. Technical success (adequate PCR) was defined as > 75% global prostate gland contrast staining. Clinical success was determined in accordance to CIRSE standards of practice.

RESULTS

One hundred sixty-five patients (mean age 68 ± 8.4 years) underwent PAE from June 2017 to March 2019. Technical and clinical success rates were 98.8% and 96.4% respectively. Clinical success rate was significantly higher in patients with adequate PCR. International Prostate Symptom Scores (IPSS) and Quality of Life (QoL) scores significantly improved at 1-, 3-, 6-, and 12-month follow-up when compared to baseline. Prostate volume (PV) and post-voiding residual bladder volume were significantly reduced at 3, 6, and 12 months in comparison to baseline. Mild (Clavien-Dindo grade I/II) and moderate (grade III) complication rates were 12.1% and 3.6% respectively.

CONCLUSIONS

By using PCR adequacy as a guide to determine the procedure endpoint for PAE, it may be possible to achieve more complete embolization and thus higher clinical success rates.

KEY POINTS

• By using PCR adequacy as a guide to determine the procedure endpoint for PAE, it may be possible to achieve more complete embolization and thus higher clinical success rates.

Efficacy and safety of prostatic artery embolization for benign prostatic hyperplasia: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To investigate the efficacy and safety of prostatic artery embolization (PAE) vs. transurethral resection of the prostate (TURP) in patients affected by benign prostatic hyperplasia (BPH). We also reviewed mean changes from baseline in PAE at selected follow-up points.

METHODS

PubMed, Web of Science, and Embase were searched up to May 1, 2020. Randomized controlled trials on PAE were collected according to specific inclusion and exclusion criteria. Meta-analyses were performed using RevMan 5.3, STATA 14, and GraphPad Prism 8. Pooled patient-reported scores and functional outcomes were calculated by using a fixed or random-effect model.

RESULTS

Eleven articles met our selection criteria and ten independent patient series were included in the final analysis. Pooled estimates suggested no significant difference between TURP and PAE for patient-reported outcomes including International Prostate Symptom Score (2.32 (- 0.44 to 5.09)) and quality of life (0.18 (- 0.41 to 0.77)) at 12 months. PAE was less effective regarding improvements in most functional outcomes such as maximum flow rate, prostate volume, and prostate-specific antigen. Moreover, PAE may be associated with relatively fewer complications, lower cost, and shorter hospitalization. After the PAE procedure, the overall weighted mean differences for all outcomes except sexual health scores were significantly improved from baseline during follow-up to 24 months.

CONCLUSION

PAE is non-inferior to TURP with regard to improving patient-reported outcomes, though most functional parameters undergo more changes after TURP than after PAE. Moreover, PAE can significantly continue to relieve symptoms for 24 months without causing serious complications.

KEY POINTS

• PAE is as effective as TURP in improving subjective symptom scores, with fewer complications and shorter hospitalization times. • PAE is inferior to TURP in the improvement of most functional outcomes. • Improvements due to PAE are durable during follow-up to 24 months.

Initial Canadian Experience of Prostate Artery Embolization for Symptomatic Benign Prostatic Hyperplasia: Midterm Outcomes

INTRODUCTION

This study aimed to assess the midterm outcomes and safety of prostate artery embolization (PAE) for the treatment of benign prostatic hyperplasia (BPH).

METHODS

A single-center, retrospective review of PAE performed for BPH was performed. Validated International Prostate Symptom Score (IPSS), quality of life (QoL) index, and International Index for Erectile Function (IIEF-5) questionnaires were completed at baseline and at least 12 months post-procedure. Prostate imaging was performed preprocedure as well as 3 months and 12 months post-procedure to assess prostate volume (PV). Uroflowmetry was also performed at baseline and 12 months post-procedure to assess urine flow rate (Q_max) and post-void residual (PVR) volume. Adverse events were graded according to Society of Interventional Radiology (SIR) guidelines.

RESULTS

Eighty male patients underwent the PAE procedure (mean age 69 years). Prostate volume decreased significantly from a mean volume 156 to 107 mL after 12 months post-procedure, commensurate with a mean reduction of 27.5% (P < .05). Significant improvements were seen in IPSS (21.8 vs 10.5) and QoL (4.5 vs 2.0) from baseline to 12 months post-procedure (P < .05). There was no significant change in IIEF-5 score. There was a significant reduction in PVR (202 vs 105 mL) and improvement in Q_max (5.9 vs 10.0 mL/s) between baseline and 12 months post-procedure (P < .05). No major complications occurred; 4 minor complications occurred (SIR grade A or B).

CONCLUSION

Prostate artery embolization achieved a clinically and statistically significant prostate volume reduction, symptom and QoL improvement, and enhanced uroflowmetry parameters in patients with BPH.