The European Association of Urology (EAU) and the American Urological Association (AUA) guidelines recommend bipolar transurethral vaporization of the prostate (B-TUVP) for men with prostate volumes (PVs) of 30–80 ml but not for those with PV >80 ml. In contrast, holmium laser enucleation of the prostate (HoLEP) has broader indications for its use than B-TUVP. It is currently recommended for the treatment of moderate (PV 30-80 ml) and large (PV >80 ml) benign prostatic enlargement (BPE). 
Recently, we introduced the second-generation B-TUVP using an oval electrode (Olympus, Japan) and demonstrated its efficacy and safety for large BPE (PV ≥100 ml). This confirmed the hypothesis that B-TUVP is an alternative treatment option for HoLEP in patients with moderate and large BPE. 
This study was a retrospective review of two regional, high-volume centers that compared the efficacy and safety of second-generation B-TUVP against HoLEP in patients with moderate and large BPE, with the aim of evaluating and eventually establishing the future outlook of B-TUVP for BPE treatment.

We retrospectively compared clinical data from two regional, high-volume centers employing second-generation B-TUVP and HoLEP for BPE treatment. All procedures were performed between September 2016 and October 2021. Patients with suspected impaired detrusor function, active urinary tract infection, prostate cancer, bladder cancer, urethral stricture, or dementia who were not able to complete outcome measurements were excluded from the study. The two centers shared the same surgical indications. Briefly, surgical indications were International Prostate Symptoms Score (IPSS) >7, maximum flow rate (Qmax) <10 ml/s, persistent or recurrent urinary retention or bladder stones, or post-void residual urine volume (PVR) >100 ml. 
The B-TUVP and the HoLEP patient-oriented and treatment outcomes were then retrospectively compared. The main treatment outcomes were measured by IPSS and IPSS Quality of Life Index (IPSS-QoL) at preoperative baseline, then at 1and 3 postoperative months (POM).

This study enrolled 177 consecutive patients with BPE who underwent B-TUVP and 286 consecutive patients who underwent HoLEP. Thus 16 patients (7 with prostate cancer, 2 with bladder cancer, 4 with dementia and 3 in the terminal stages of non-prostate cancer) were excluded from the B-TUVP group. Because of no records of preoperative PV, 4 more patients from the B-TUVP group and 5 patients from the HoLEP group, were also excluded.

In uncatheterized patients with PV 30-80 ml from both the B-TUVP and HoLEP groups, total IPSS and IPSS-QoL scores significantly decreased after surgery (at 1 and 3 POM) compared to baseline within each group (P<0.001). Between B-TUVP and HoLEP groups, total IPSS was significantly lower in HoLEP than in B-TUVP at 1 and 3 POM. In catheterized patients with PV 30-80 ml, the rate of achieving catheter-free status after surgery was relatively higher in HoLEP than in B-TUVP but this was not statistically significant. A total of 2 cases in the B-TUVP group required a 2nd procedure for persistent LUTS after the initial session.

In uncatheterized patients with PV >80 ml in both B-TUVP and HoLEP groups, total IPSS and IPSS-QoL scores significantly decreased after surgery (at 1 and 3 POM) compared to baseline within each surgery group (P<0.001, Table 1). Between B-TUVP and HoLEP, total IPSS and IPSS-QoL were significantly lower in the HoLEP group than in the B-TUVP group at 1 and 3 POM. In catheterized patients with PV >80 ml, the rate of achieving catheter-free status after surgery was significantly higher in HoLEP than in B-TUVP. A total of 8 cases of B-TUVP required 2nd procedures to address persistent urinary retention, whereas 3 cases of HoLEP had to undergo repeat sessions owing to incomplete morcellation.

The incidence of postoperative fever was significantly higher in B-TUVP than in HoLEP in patients with a PV 30-80 ml but not in PV >80 ml (Table 2). There were 2 cases of septic shock needing catecholamine therapy and one postoperative cerebral cortex infarction (Clavien-Dindo Grade IVb) in a B-TUVP (PV >80 ml) patient. Postoperative urinary incontinence and complications associated with morcellation occurred only in the HoLEP group and all cases were treated conservatively (Clavien-Dindo GradeⅠ). Both B-TUVP and HoLEP (PV >80 ml) groups had a case each which necessitated a resurgery for transurethral coagulation (Clavien-Dindo Grade Ⅲb).

This study was the first retrospective comparative study evaluating the short-term efficacy and safety of second-generation B-TUVP and HoLEP for moderate (PV 30-80 ml) and large (PV >80 ml) BPE. In uncatheterized patients, voiding symptoms and patients’ QoL derived from IPSS and IPSS-QoL clearly and significantly improved after B-TUVP and HoLEP in both PV 30-80 ml and PV>80 ml, but these improvement rates were consistently greater in HoLEP than in B-TUVP. 
In catheterized patients, both B-TUVP and HoLEP exhibited their efficacy through high rates of postoperative catheter-free status in this study. Particularly, for catheterized patients with PV >80 ml, the postoperative catheter-free rate was significantly higher in HoLEP than in B-TUVP with a similar trend seen in patients with PV 30-80 ml. These findings indicated that HoLEP has clinical advantages over B-TUVP in achieving catheter-free status for patients with urinary retention, especially in patients with PV >80 ml. B-TUVP may have less of an advantage in producing this outcome as it sometimes results in inadequate vaporization and residual adenoma compared to HoLEP in PV >80 ml.
The most common surgical complication of both B-TUVP and HoLEP was postoperative fever which was more frequent in B-TUVP than in HoLEP, especially in patients with PV 30-80 ml. One of the general drawbacks of HoLEP was its prerequisite for morcellation during surgery which subsequently leads to serious operative complications including bladder injury. Furthermore, the rate of postoperative incontinence was significantly higher in HoLEP than in B-TUVP. Urinary incontinence was well-documented as a major complication of HoLEP, with incidence rates at 10.7-16.2%. Most case of urinary incontinence were reported as transient and, in this study, all urinary incontinence was transient and ceased without any treatment within 6 months. The rate of hemoglobin reduction was lower in B-TUVP than in HoLEP suggesting that the bipolar system has a higher hemostatic capacity than holmium laser.

This is the first retrospective study investigating the short-term efficacy and safety of second-generation B-TUVP in comparison with HoLEP for moderate and large BPE. 
For both uncatheterized and catheterized patients, improvement in LUTS, achievement of catheter-free status, and the non-necessity of a follow-up procedure were predominant in HoLEP, and these outcomes were more prominent in patients with large BPE of PV >80 ml. 
However, B-TUVP resulted in less blood loss postoperatively, with shorter operative duration, and less urinary incontinence in both moderate and large BPE suggesting that B-TUVP is a well-tolerated surgical modality, irrespective of prostate volume, over HoLEP.

Continence 2S2 (2022) 100414
DOI: 10.1016/j.cont.2022.100414