Urologic outcomes
International prostate symptom score
Pisco et al. has published the largest cohort of PAE patients with at least 6 months of follow up (Pisco et al. 2016b). This retrospective study of 630 consecutive patients showed short term (first 12 months), medium term (1–3 years), and long term (3–6.5 years) IPSS improvements by a mean of − 13.71 ± 7.16, − 14.5 ± 7.36, and − 16.94 ± 8.7 respectively (p < 0.0001) (Table 3). In a recent meta-analysis of PAE, Kuang et al. 2017, which included 788 patients from the literature, found IPSS improved from a baseline mean of 23.75 to 10.94, 9.31, and 8.90 at 6, 12, and 24 months respectively (p < 0.001 for all) (Antunes et al. 2013).
The UK-ROPE study was published this year and evaluated the improvement in IPSS for PAE compared to baseline, as well as to TURP in a non-randomized registry format (Ray et al. 2018). This study enrolled 216 patients in the PAE and 89 in the TURP arms. At the primary endpoint of 12 months PAE demonstrated a significant decrease in IPSS of 10.9, however, less than that of TURP which was 15.2.
Very few randomized controlled trials comparing PAE to other treatments exist. In the largest, Gao et al. randomized 114 patients to TURP (n = 57) or PAE (n = 57) (Gao et al. 2014). The authors found that the TURP cohort showed significantly better improvement in IPSS at 1 and 3 months, however, the treatments became equivalent at 6 months and remained equivalent at the 12 and 24 month time points. The initial differences, at 1 and 3 months, may be the result of the need for prostatic tissue to undergo necrosis and tissue remodeling after PAE, for symptoms to abate. In 2018 Abt et al. published another randomized controlled trial comparing PAE and TURP (Abt et al. 2018). This open-label, single center, randomized controlled trial was completed with the primary outcome of non-inferiority of PAE to TURP in terms of IPSS at 3 months. The trial randomized 103 patients, however, they only compared the 48 that underwent PAE to the 51 that underwent TURP. While there was no statistically significant difference in the mean IPSS improvement between the PAE (− 9.23 points) and TURP (− 10.77 points) cohorts at 3 months (p = 0.31), non-inferiority of PAE could not be shown secondary to the variation among outcomes (p = 0.17).
Quality of life
Pisco et al. also demonstrated encouraging improvements in quality of life (QoL) with a mean improvement of − 1.94 ± 1.20, − 1.98 ± 1.21, − 1.74 ± 1.45 at short term, medium term, and long term follow up respectively (p < 0.0001 as compared to baseline) (Pisco et al. 2016b). In a recent meta-analysis, the mean QoL had improved from a baseline mean of 4.63 to 2.48, 2.11, and 2.36 at 6, 12, and 24 months respectively (p < 0.001 for all) (Antunes et al. 2013).
The UK-Rope trial showed QoL measurements had improved by a mean of 2.6 in the PAE cohort, a marked improvement but not as significant as the TURP cohort’s improvement of 3.4. The study completed a propensity matched analysis for non-inferiority of PAE to TURP which failed to show that PAE was non-inferior in terms of QoL at 12 months (Ray et al. 2018). Abt et al. demonstrated no statistically significant difference in the change in QoL between the PAE (− 2.33) and TURP (− 2.69) cohorts at 3 months (p = 0.15) in there randomized controlled trial (Abt et al. 2018). While Gao et al. found that the TURP cohort showed significantly better improvement in QoL at 1 and 3 months, however, the treatments became equivalent at 6 months and remained equivalent at 12 and 24 months (Gao et al. 2014).
Maximal flow rate
Pisco et al. demonstrated Qmax also increased significantly over baseline with short term, medium term, and long term follow up patients experiencing a mean improvement of 3.07 mL/s ± 5.84, 4.12 mL/s ± 11.32, and 7.98 mL/s ± 4.83, respectively (p < 0.0001). A recent meta-analysis demonstrated Qmax improved from a baseline mean of 8.34 mL/s to 14.26 mL/s, 15.91 mL/s, and 16.91 mL/s at 6, 12, and 24 months respectively.
Abt et al. in there randomized controlled trial did show a statistically significantly better increase in patients Qmax following TURP as compared to PAE (p < 0.05), despite PAE patients showing significant improvement over base line (Abt et al. 2018). However, Gao et al. in there randomized controlled trial failed to show statistically significant differences in Qmax improvement after 3 months, with the improvements at 24 months being nearly identical (Gao et al. 2014).
Prostate volume and post void residual
Pisco et al. showed PV and PVR improved significantly over base line (p < 0.0001) (Pisco et al. 2016b). A recent meta-analysis found significant improvements in PV and PVR over baseline as well (Antunes et al. 2013).
Abt et al. in there randomized controlled trial found that patients PVR was significantly improved from baseline in the PAE cohort, but was statistically inferior to the improvement in the TURP cohort (Abt et al. 2018). However, Gao et al. in there randomized controlled trial failed to show statistically significant differences in PVR improvement after 3 months, with the improvements at 24 months being nearly identical (Gao et al. 2014).
These larger studies highlight the findings that many other authors have documented. The improvement in QoL, Qmax, and IPSS over baseline are significant and while data over 2 years is sparse the treatment has remained durable thus far.
Complications
Complication profiles are paramount for any new procedure in the BPH induced LUTS space, as TURP is an excellent surgical option in terms of clinical outcomes, however it’s complication profile is what leaves room for improvement. To date the complication profile of PAE has been very promising. Pisco et al. reported 2 major complications (bladder ischemia requiring surgery and persistent perineal pain) in their retrospective review of 630 patients resulting in a major complication rate of 0.3% (Pisco et al. 2016b). Two meta-analyses which included 788 and 840 patients respectively reported major complication rates of 0.4% (3/788) and 0.1% (1/840) respectively (Antunes et al. 2013; Wang et al. 2015). In a randomized controlled trial comparing TURP to PAE, Gao et al. reported that 14.8% (8/54) of PAE and 7.5% (4/53) of TURP patients had major complications (Gao et al. 2014). These results were inconsistent with previously published data, in the number of complications experienced in the PAE group. Gao et al., choose to label technical and clinical failures as major complications, which has been criticized by other authors (Wang et al. 2016). The authors also choose to not consider hemorrhage requiring blood transfusion as a complication in the TURP cohort. If we adjust the Gao data to be more in line with published standards, we find that PAE cohort consisted of no major complications and the TURP cohort experienced major complications in 7.5% (4/53) of patients (Amouyal et al. 2016a). The lack of any retrograde ejaculation, impotence, or incontinence in the TURP group has also raised questions regarding this study’s adverse event reporting and would perhaps further the adverse event margin (Wang et al. 2016). The concerns with the adverse event reporting in Gao has been further supported by the superior complication profile and length of stay demonstrated by a recent randomized controlled trial (Abt et al. 2018) and propensity score matched registry (Ray et al. 2018). Abt et al., in their randomized control trial, found that treatment related adverse events were half as frequent after PAE than TURP (p = 0.003). The length of stay was also found to be significantly less in both of these articles (Ray et al. 2018; Abt et al. 2018).
The most common minor complication of PAE has varied depending on the publication. A recent meta-analysis of 840 patients and Pisco et all in there review of 630 patients found that dysuria was the most common minor complication occurring in 10.4% (87/840) and 24.1% (152/630) of patients respectively (Pisco et al. 2016b; Grosso et al. 2015). Kuang et al. 2017 in their meta-analyses of 788 patients found that acute urinary retention was the most common minor complication occurring in 7.61% of cases (60/788) (Antunes et al. 2013). Other commonly seen minor complications included hematospermia, minimal rectal bleeding, and urinary tract infections.