Clinical predictive factors in prostatic artery embolization for symptomatic benign prostatic hyperplasia: a comprehensive review

Prostatic Artery Embolization: Lessons From 551 Procedures at a Single-Center

RATIONALE AND OBJECTIVES

This retrospective study evaluates the efficacy and safety of Prostatic Artery Embolization (PAE) for the treatment of benign prostatic hyperplasia (BPH) over five years at a single center, conducted by an experienced interventional radiologist.

MATERIALS AND METHODS

We analyzed 551 PAE interventions from January 2019 to July 2023. Key metrics included patient demographics, procedural details (radiation exposure, particle size), complication rates, pre- and post-interventional prostatic volume (PV), Prostate-specific Antigen (PSA) levels, International Prostate Symptom Score (IPSS), Quality of Life (QoL) scores and International Index of Erectile Function (IIEF) scores. We assessed data normality, performed group and paired sample comparisons, and evaluated correlations.

RESULTS

For 551 men, the average patient age was 68.81 ± 8.61 years undergoing bilateral embolization. The particle size predominantly used was 100-300 µm (n = 441). PAE lead to significant (p < .001) reduction of both PV (-9.67 ± 14.52 mL) and PSA level (-2,65 ± 1.56 ng/mL) between pre- and three months after PAE. Substantial improvement were observed for IPSS (-9 points) and QoL scores (-2 points), with stable IIEF scores. Only minor complications (n = 16) were reported, and no major complications were observed. Between the first PAE in 2019 and the routinely performed PAE in 2023 significant (p < .0001) reductions in fluoroscopy (-25.2%), and procedural times (-26.1%) were observed.

CONCLUSION

In conclusion, PAE is a safe and effective treatment for BPH, offering significant improvements in lower urinary tract symptoms (LUTS) and QoL while maintaining sexual function.

A correlation study between prostate necrosis rate calculated by 3D Slicer software and clinical efficacy of prostatic artery embolization, along with an analysis of predictors of clinical success after prostatic artery embolization

PURPOSE

To analyze the correlation between the prostate necrosis rate at 1-month after prostatic artery embolization (PAE) and the clinical efficacy at 1-year after PAE, and to explore potential predictors of clinical success after PAE for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH).

METHODS

The prostate magnetic resonance imaging data at 1-month after PAE were imported into 3D Slicer software for calculating the prostate necrosis rate and thus analyzing the relationship between the prostate necrosis rate at 1-month after PAE and the efficacy score ratio at 1-year after PAE. The 151 patients with PAE technical success were divided into a clinical success group (n = 126) and a clinical failure group (n = 25). Independent predictors of clinical success after PAE were analyzed by multifactorial logistic regression, and the predictive performance of each factor was evaluated by applying the receiver operating characteristic curve and the area under the curve (AUC).

RESULTS

There was a linear negative correlation between the prostate necrosis rate at 1-month after PAE and the efficacy score ratio at 1-year after surgery (P < 0.001). In the clinical success group, both the initial prostate volume (PV) and the prostate necrosis rate at 1-month after PAE were significantly higher than in the clinical failure group (P < 0.001), and acute urinary retention (AUR) and adenomatous-dominant BPH were also associated with clinical success (P < 0.05). Multifactorial logistic regression analysis revealed that larger initial PV, a higher prostate necrosis rate at 1-month after surgery, and AUR were independent predictors of clinical success after PAE. The AUC values for these three indicators and their combination were 0.720, 0.928, 0.599, and 0.951, respectively, in which the prostate necrosis rate at 1-month after PAE demonstrating a high predictive value.

CONCLUSION

The higher the prostate necrosis rate at 1-month after PAE, the better the clinical efficacy at 1-year after PAE is likely to be, and the prostate necrosis rate at 1-month after PAE is expected to become a predictor of clinical success after PAE.

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.

Benefits of Repeat Prostatic Artery Embolization on Persistent or Recurrent Lower Urinary Tract Symptoms in Patients with Benign Prostatic Hyperplasia

OBJECTIVES

To evaluate the benefits of repeat prostatic artery embolization (rePAE) for patients with persistent or recurrent symptoms after initial prostatic artery embolization (PAE).

MATERIALS AND METHODS

This is a single-center retrospective study of all patients who underwent a rePAE between December 2014 and November 2020 for persistent or recurrent lower urinary tract symptoms. Symptoms were assessed before and after PAE and rePAE, using the International Prostate Symptom Score and quality of life (QoL) questionnaires. Patient characteristics, anatomical presentations, technical success rates, and complications of both procedures were collected. Clinical failure was defined as one of the following: less than 2 points' decrease in QoL, a QoL score higher than 3, acute urinary retention, and secondary surgery.

RESULTS

A total of 21 consecutive patients (mean age: 63.8 ± 8.1; [40-75] years) who underwent rePAE were included. The median follow-up after PAE was 27.7 [18.1-36.9]) months and 8.9 [3.4-10.8] months after rePAE. rePAE was performed at a mean of 19 ± 11.1 [6.9-49.6] months following PAE, and the overall clinical success rate was 33% (7/21). In patients undergoing rePAE because of persistent symptoms, the clinical success rate (18%) was non-significantly lower than that for patients treated for recurrent symptoms (50%) [OR 4.5 (95% CI 0.63-32 P = 0.13)]. The main anatomical revascularization pattern was recanalization of the native prostatic artery (29/45, 66%).

CONCLUSION

Patients who experience recurrent symptoms after PAE may benefit more from rePAE than those with persistent symptoms after PAE. Clinical success rates seem to be relatively low in both clinical scenarios.

Influence of benign prostatic hyperplasia patterns detected with MRI on the clinical outcome after prostatic artery embolization

BACKGROUND

To investigate the influence of benign prostatic hyperplasia (BPH) patterns detected with MRI on clinical outcomes after prostatic artery embolization (PAE).

MATERIALS & METHODS

This retrospective study included 71 consecutive patients with lower urinary tract symptoms (LUTS), who underwent magnetic resonance imaging (MRI) of the prostate followed by PAE at a single centre. MRI scans were evaluated and BPH patterns were determined according to Wasserman type and a modified BPH classification. Additionally, scans were evaluated regarding the presence of adenomatous-dominant benign prostatic hyperplasia (AdBPH). LUTS were assessed using the International Prostate Symptom Score (IPSS) and urinary flow rate (Qmax). Follow-up examination included MRI and clinical outcome.

RESULTS

For clinical outcome at follow-up, IPSS showed median reduction of 54% (IQR 41-75%) and Qmax improved by 4.1 ml/s. We noted significant reduction in volume, intraprostatic protrusion, and prostatic urethral angle in our collective (p < 0.01). Median volume reduction was 25% (IQR 15%-34%). Bilateral embolization was a significant predictor for volume reduction at follow-up. Multiple linear regression analysis showed significant effect of high initial volume on reduction in IPSS after treatment (p < 0.01). Presence of AdBPH was significantly associated with both, volume loss and clinical improvement in terms of IPSS reduction (p < 0.01). Neither BPH pattern based on the Wassermann type nor modified BPH classification were significantly related with postinterventional IPSS and volume loss.

CONCLUSIONS

Men benefit from PAE regardless the macroscopic BPH MRI pattern. Preinterventional prostate volume and presence of AdBPH on MRI should be considered for outcome prognosis after PAE.

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

Background

Prostatic artery embolization (PAE) is an alternative treatment for symptomatic benign prostatic hyperplasia (BPH) in men. A technical modification of conventional PAE has been developed in a canine prostate model consisting of prostatic artery occlusion (PAO) using Onyx^® whose therapeutic effect is prostate shrinkage. However, the underlying mechanisms are not well clarified. The purpose was to evaluate the biological mechanisms responsible for therapeutic effects of PAO in the canine prostate.

Methods

Ten adult male beagles (5.0±0.82 years) underwent PAO with Onyx-18 (n=7) and prostatic artery angiography as control (n=3). Blood samples were taken at different time points of follow-up (baseline, 1 week, 2 weeks, 1 month, 3 months and 6 months) to measure the serum canine prostate specific esterase (CPSE). MRI examinations were also performed to document the prostate volume (PV) before and after interventions at different time points of follow-up. Prostates were harvested at 2 weeks (n=2) in the PAO-group, and the remaining ones (n=8) at 6 months for the determinations of intraprostatic testosterone and dihydrotestosterone (DHT) by ELISA, apoptosis by TUNEL assay and histopathological study.

Results

The mean serum CPSE concentration started to decrease significantly from 2 weeks to 6 months after PAO along with PV compared with baseline data. In addition, a moderate but significant correlation was observed between CPSE and PV (r=0.655, P=0.000). Regarding intraprostatic androgens, testosterone was significantly higher after PAO than control (19.70 vs. 4.87 ng/mL, P=0.002), whereas DHT was lower but no significant (112.52 vs. 138.35 pg/mL, P=0.144). In histological study, PAO induced a severe hemorrhagic necrosis in the whole prostates along with inflammatory cell infiltration at early 2 weeks, and then diffuse interstitial fibrosis with atrophy of the glandular epithelium and intraprostatic cavity formation at 6 months. Apoptosis was detected in all specimens with higher apoptotic index after PAO at 2 weeks (7.35%) and at 6 months (4.38%) compared with control (2.64%), without statistically significant difference between groups.

Conclusions

PAO induces hemorrhagic ischemia predominantly resulting in necrosis rather than apoptosis with prostate shrinkage. CPSE is a potential biomarker to assess the response to PAO in the canine prostate.

Prostatic Artery Embolization for Benign Prostatic Hyperplasia—A Primer for Interventional Radiologists

Male patients over 50 years with lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia (BPH) are potential candidates for prostatic artery embolization (PAE). PAE is not a perfect fit for all BPH patients. Careful pre- and postpostprocedural evaluation/consultation with correct selection of patients should be tailored on an individual basis. Evaluated parameters include the following: LUTS severity quantification with validated questionnaires as the international prostate symptom score (IPSS) and quality of life (QoL), erectile and ejaculatory evaluation with validated questionnaires, blood tests including full blood count, coagulation profile, renal function and total/free prostate-specific antigen (PSA), prostate volume measured by multiparametric magnetic resonance (mpMR) of the prostate and/or transrectal ultrasound, uroflowmetry measuring the peak urinary flowrate (Qmax), and postvoid residual urine (PVR). Correct arterial anatomy identification with either computed tomography (CT) angiography, MR angiography, or intraprocedural cone-beam CT (CBCT) are suggested for a confident procedure and avoiding potential complications. The minimally invasive nature of PAE with a faster recovery, preserving the sexual function, and comparable results to standard prostatic surgery make the procedure an attractive choice for many male patients suffering with this condition. Patients should be informed about the potential for higher retreatment rates and shorter duration of treatment effect when compared with standard prostatic surgery. In this comprehensive review, we provide an updated toolbox for all interventional radiologists interested in the PAE practice for patients with BPH. We explain how to evaluate patients during consultation before and after PAE, describe the preprocedural imaging required, explain the technique, and narrate how to optimize outcomes. Finally, we review the level of evidence of PAE for BPH.

Prostatic artery embolization for bladder outlet obstruction in the setting of prior posterior urethroplasty

This case presents a patient with a remote history of complex posterior urethral repair related to a prior motorcycle accident who presented to the urology clinic in urinary retention with associated lower urinary tract symptoms. Due to his altered anatomy, traditional outlet procedures were deferred due to significant reported risks of post treatment urinary incontinence. Decision was made to proceed with prostatic artery embolization, and at follow up he reported resolution of his urinary retention and significant symptomatic improvement in his voiding without development of urinary incontinence.

Prostatic artery embolization: magnetic resonance image (MRI) findings in the early detection of prostate infarction in a canine spontaneous benign prostatic hyperplasia model

Background

The purpose was to assess the association between prostate infarction and prostate volume (PV) reduction after prostatic artery embolization (PAE) and define the best time point in detection of prostate infarction.

Methods

Ten male beagles (3.5–6.4 years) with spontaneous benign prostatic hyperplasia (BPH) underwent PAE. Magnetic resonance image (MRI) was conducted immediately before and 1 week, 2 weeks and 1 month after PAE to document prostate infarcts and measure PV. The sum of infarct areas (SUMIA) was measured and calculated using OsiriX software. Spearman’s rank correlation was used to estimate the relationship of PV reduction rate with infarction percentage and SUMIA reduction.

Results

In comparison with baseline data, significant PV reduction (P<0.001) occurred at 2 weeks and continued to decrease substantially (P=0.004) from 2 weeks to 1 month after PAE. In the same fashion, significant decrease in both SUMIA and infarction percentage was observed from 1 to 2 weeks (P=0.002), and subsequently to 1 month (P=0.039 and P=0.016, respectively). Spearman’s rank correlation test demonstrated infarction percentage at 1 week had a stronger correlation (r=0.880, P=0.001) with PV reduction rate at 1 month than infarction percentage at 2 weeks (r=0.733, P=0.016). PV reduction rate had a significant correlation with decrease in SUMIA (r=0.854, P=0.002) at 1 month after PAE.

Conclusions

One week after PAE is an ideal time point to evaluate prostate infarction. Prostate infarction percentage at 1 week is a good predictor for prostate shrinkage at 1 month after PAE.