Clinical and technical evidence

A literature search was carried out for this briefing in accordance with the interim process and methods statement. This briefing includes the most relevant or best available published evidence relating to the clinical effectiveness of the technology. Further information about how the evidence for this briefing was selected is available on request by contacting mibs@nice.org.uk.

Published evidence

Four studies are summarised in this briefing.

One meta‑analysis of 1,690 people (Zheng et al. 2019) is included which compares outcomes for people with benign prostatic hyperplasia that had either button‑type bipolar plasma vaporisation of the prostate (BPV) or transurethral resection of the prostate (TURP). The meta‑analysis consists of 9 randomised controlled trials, 1 prospective non-randomised study and 1 retrospective study. There was also 1 randomised prospective study (Abdelwahab et al. 2019) and 1 retrospective study (Aboutaleb 2015) included which compared BPV with TURP. One further retrospective analysis (Giulianelli et al. 2019) comparing BPV with open prostatectomy in people with prostates larger than 80 g has been included in this briefing.

The clinical evidence and its strengths and limitations is summarised in the overall assessment of the evidence.

Overall assessment of the evidence

The evidence base for the PLASMA system with button electrode consists of several randomised controlled trials comparing the technology directly with other methods of procedure, mainly TURP. There are also several prospective and retrospective studies which commonly include a single arm of patients that had a procedure using the button electrode. As well as assessing the health‑related outcomes after the procedure, there is a focus on the incidence of complications that are commonly seen with other interventions and the efficiency and safety of the surgical procedure itself. A major limitation of the evidence base is that there are no studies that have been done within a UK context, although some have been done at European centres. The PLASMA system is in use at centres throughout the UK with loop and roller electrodes, but it is unclear if the button electrode has been widely used by clinicians in NHS practice.

Zheng et al. (2019)

Intervention and comparator

BPV, compared with TURP.

Key outcomes

Efficacy data was quantified using the following outcomes: International Prostate Symptom Score (IPSS), maximum flow rate (Qmax), post‑voiding residual (PVR) and quality of life. Differences between the 2 groups were represented by standard mean differences (SMD) with confidence intervals and odds ratios (OR) for dichotomous variables. Safety and tolerability data were also compared for both groups.

No significant differences in IPSS were seen at 1, 3 and 12 months across both groups. The TURP group had better 6‑month IPSS than the BPV group (SMD=0.36 [0.08 to 0.63], p=0.01). The TURP group had better 1‑month (SMD=-0.38 [-0.63 to -0.12], p=0.004), 6‑month (SMD=-0.73 [-0.99 to -0.46], p<0.00001) and 12‑month (SMD=-0.47 [-0.85 to -0.10], p=0.01) Qmax than the BPV group. However, no significant difference was seen in 3‑month postoperative Qmax. Postoperative values of PVR were significantly lower than preoperative values in both groups. The TURP group had a higher 3‑month PVR (SMD=0.14, [-0.08 to 0.36], p=0.21) and lower 6‑month PVR (SMD=1.18 [0.87 to 1.48], p<0.00001) compared with the BPV group. The 12‑month PVR was similar. Quality of life estimates for TURP yielded better results than the BPV group at both 3 months (SMD=-0.24 [-0.48 to -0.01]) and 6 months (SMD=-0.62 [-0.91 to -0.33]).

The BPV group had significantly fewer total complications (OR=0.52 [0.40 to 0.69], p<0.0001), lesser need for blood transfusion (OR=0.25 [0.09 to 0.69], p=0.005) and fewer haematuria (OR=0.27 [0.13 to 0.56], p=0.00004). No significant differences were found in postoperative urethral stricture, urinary incontinence, urinary retention, transurethral resection syndrome, urinary tract infection, recatheterisation or retreatment. Seven of the included studies compared operative time. The findings indicated that the BPV group had shorter operative time (SMD=-0.15 minutes [-0.31 to 0.01], p=0.006), shorter catheterisation time (SMD=-0.96 days [-1.12 to -0.79], p<0.00001) and shorter hospitalisation time (SMD=-0.71 days [-0.89 to -0.53], p<0.00001).

Strengths and limitations

The main strength of this meta‑analysis is that it included 9 randomised controlled trials from 2010 to 2017. This study methodology is considered to be the gold standard when comparing medical interventions. Also, all of the studies used the Olympus technology specifically for BPV whereas previous studies compared earlier BPV systems. Compared with the previous meta‑analysis assessing this technology, a larger number of efficacy and safety parameters were analysed. A limitation of the study is that most of the trials had a follow up of less than 12 months (2 studies had 3‑month follow up and 4 studies had 6‑month follow up) so only short-term efficacy and safety between BPV and TURP could be compared.

Abdelwahab et al. (2019)

Intervention and comparator

Olympus bipolar button vaporisation, compared with Olympus bipolar loop TURP.

Key outcomes

There were 44 patients included in bipolar TURP and 45 patients in the vaporisation arm. The preoperative mean prostate volume (PV) and mean IPSS were equivalent in both groups. Vaporisation was associated with a significant increase in operative time (mean 81 minutes compared with 55 minutes), less blood loss (0.8% compared with 2.0% drop in haemoglobin, p<0.001), higher postoperative urinary frequency (80% compared with 50%, p<0.001), more haematuria with clots up to 4 weeks after surgery (20% compared with 2%, p<0.001) and increased postoperative urethral stricture (11% compared with 0%, p<0.001). PV and IPSS were comparable across both treatment arms.

Strengths and limitations

A strength of this study was that patients were randomised using simple randomisation, whereby consecutive patients had alternate surgical techniques. This prevents selection bias from clinicians affecting the results of the study. In this study, a significant limitation was that all surgeries were done by a single surgeon. Therefore, the success of surgery and investigated outcomes were highly dependent on the proficiency of the surgeon in relation to the 2 techniques employed. As TURP is already standard care, it may have been done more efficiently than button vaporisation; this could explain the significant increase in operative time with vaporisation. Patients were also informed about the type of surgery they had for the purposes of informed consent. This could potentially have influenced subjective reporting at time points after the procedure.

Aboutaleb (2015)

Intervention and comparator

Olympus BPV, compared with TURP.

Key outcomes

TURP was done in 100 patients and BPV in 52 patients. The mean operative time was 53 minutes in the BPV arm and 62 minutes in the TURP arm and the indwelling catheter was removed after mean 2 days compared with 3 days. Patients in the BPV group were discharged after an average of 1 day compared with 3 days in the TURP group. Mean irrigation volume during surgery and postoperatively was significantly lower in terms of volume and hours in the BPV group. In the BPV group, 2 patients (3.8%) were noted with early complications, whereas in the TURP group 18 patients (18%) had early complications.

Short-term follow up at 3 months showed insignificant differences in IPSS, quality of life, and PVR between both groups compared with preoperative measurements, but highly significant (p=0.0001) improvements were seen in the BPV group for Qmax and Qave (average flow rate). Regardless of the technique used, results revealed highly significant improvements for patients in both groups for all outcomes after the procedure.

Strengths and limitations

This study used a relatively large patient population for both arms. As with the previous study summarised, both the BPV and TURP procedures were done in a single centre by the same surgeon. This could be acknowledged as a strength because of the absence of inter-clinician variability. However, the success of surgery and investigated outcomes were highly dependent on the proficiency of the surgeon in relation to the 2 techniques employed. Preoperative data for the 2 groups showed insignificant baseline differences for all variables, except from age and PVR. The average age was lower in the BPV group, as was PVR. These 2 variables may have had an effect on the final outcomes. The relatively short follow-up time meant that long-term outcomes and adverse events could not be seen.

Giulianelli et al. (2019)

Intervention and comparator

Olympus BPV, compared with open prostatectomy.

Key outcomes

Open prostatectomy was done in 111 patients, and 120 patients had BPV. Open prostatectomy needed significantly shorter operative time than BPV, with a weighted mean difference (WMD) of 41.5 minutes (p<0.05). Postoperative bladder irrigation time (WMD of 27.5 hours), catheterisation time (WMD of 38.14 hours) and hospital stay (WMD of 16.82 hours) were significantly shorter in the BPV group compared with the open prostatectomy group (p<0.05). The reintervention rate at 3 years was 7.5% in the open prostatectomy group and 5% in the BPV group.

The following outcome measures were recorded at 1, 3, 6, 12, 18, 24, 30 and 36 months: IPSS score, quality of life, PVR and prostate-specific antigen (PSA). PV was measured at 6, 12, 24 and 36 months. During the follow‑up period, there were no significant differences in terms of Qmax, quality of life, PVR, PSA and PV between the 2 groups at each time point. In the BPV group, significantly lower scores for IPSS were seen from 6 months to 36 months when compared with the open prostatectomy group (p=0.001).

Strengths and limitations

This study compared BPV with open prostatectomy, which is the procedure most commonly used for prostates that are larger than 80 g. The inclusion of this study provides an insight into the outcomes of BPV compared with open prostatectomy in relation to this specific population. The major strength of this study was the follow-up period of 36 months, which allowed long-term efficacy and adverse event data to be captured. Also, no significant baseline differences were present between the 2 groups before the procedures. The same surgeon did all the surgeries and was considered adequately trained having already completed more than 300 procedures. The study authors recognised that the retrospective design of the study was a major limitation, and the use of a single centre means results depend on the enrolled population and cannot necessarily be extended to other populations.

Sustainability

No sustainability claims have been made by the company.

Recent and ongoing studies

Transurethral Vapor Enucleation Resection of the Prostate (TVERP), Bipolar TURis and HoLEP. ClinicalTrials.gov identifier: NCT04398420. Status: not yet recruiting. Indication: benign prostatic hypertrophy. Devices: TVERP, Bipolar TURis (transurethral resection in saline) and HoLEP (holmium laser enucleation of the prostate). Estimated study completion date: June 2024.