Aquablation for the treatment of lower urinary tract symptoms in men with benign prostatic hyperplasia

Review question

How does Aquablation compare to other procedures in patients with bothersome urinary symptoms caused by an enlarged prostate?

Background

An enlarged prostate may cause bothersome urinary tract symptoms, such as having to urinate often during the day or night, having a weak stream, and the feeling of not completely emptying the bladder. When lifestyle changes (like drinking less liquids) or medications do not help, men may choose to have surgery, such as a transurethral resection of the prostate. However, this procedure may cause unwanted effects, such as erection and ejaculation problems, or require retreatment. This review looks at the results of Aquablation, which is a newer treatment that uses high-pressure water to remove prostate tissue and help with urinary tract symptoms.

Study characteristics

We looked for all studies that compared Aquablation to transurethral resection of the prostate. We included both studies in chance decided how men were treated and studies in which men and their urologist decided. We searched for studies up to 11 February 2019.

Key results

We found only one study in which chance decided how men were treated. The study compared Aquablation to transurethral resection of the prostate. On average, men were about 66 years old. We did not find any other studies.

We found that Aquablation likely improves urinary symptoms similarly to transurethral resection of the prostate and may also lead to similar quality of life. Rates of unwanted serious effects may also be similar but we are very uncertain about this.

Men who have Aquablation may have a similar risk of needing a repeat procedure as those having transurethral resection of the prostate but we are very uncertain of this finding.

Aquablation may make little to no difference to erectile function but may have fewer issues with ejaculation, but we are very uncertain of both findings.

These findings are based on a single study funded by the company that makes the device used for Aquablation. All data were limited to 12 months' follow-up or less and prostate size was less than or equal to 80 mL.

Certainty of the evidence

Our certainty about the evidence we found ranged from moderate to very low due to shortcomings in how the study was done and small study size. This means that we have either moderate, limited or very little confidence in the results, depending on the outcome.

Authors' conclusions: 

Based on short-term (up to 12 months) follow-up, the effect of Aquablation on urological symptoms is probably similar to that of TURP (moderate-certainty evidence). The effect on quality of life may also be similar (low-certainty evidence). We are very uncertain whether patients undergoing Aquablation are at higher or lower risk for major adverse events (very low-certainty evidence). We are very uncertain whether Aquablation may result in little to no difference in erectile function but offer a small improvement in preservation of ejaculatory function (both very low-certainty evidence). These conclusions are based on a single study of men with a prostate volume up to 80 mL in size. Longer-term data and comparisons with other modalities appear critical to a more thorough assessment of the role of Aquablation for the treatment of LUTS in men with BPH.

Read the full abstract...
Background: 

New, minimally invasive surgeries have emerged as alternatives to transurethral resection of the prostate (TURP) for the management of lower urinary tract symptoms (LUTS) in men with benign prostatic hyperplasia (BPH). Aquablation is a novel, minimally invasive, water-based therapy, combining image guidance and robotics for the removal of prostatic tissue.

Objectives: 

To assess the effects of Aquablation for the treatment of lower urinary tract symptoms in men with benign prostatic hyperplasia.

Search strategy: 

We performed a comprehensive search using multiple databases (the Cochrane Library, MEDLINE, Embase, Scopus, Web of Science, and LILACS), trials registries, other sources of grey literature, and conference proceedings published up to 11 February 2019, with no restrictions on the language or status of publication.

Selection criteria: 

We included parallel-group randomised controlled trials (RCTs) and cluster-RCTs, as well as non-randomised observational prospective studies with concurrent comparison groups in which participants with BPH who underwent Aquablation.

Data collection and analysis: 

Two review authors independently assessed studies for inclusion at each stage, and undertook data extraction and 'Risk of bias' and GRADE assessments of the certainty of the evidence. We considered review outcomes measured up to and including 12 months after randomisation as short-term and beyond 12 months as long-term.

Main results: 

We included one RCT with 184 participants comparing Aquablation to TURP. The mean age and International Prostate Symptom Score were 65.9 years and 22.6, respectively. The mean prostate volume was 53.2 mL. We only found short-term data for all outcomes based on a single randomised trial.

Primary outcomes

Up to 12 months, Aquablation likely results in a similar improvement in urologic symptom scores to TURP (mean difference (MD) −0.06, 95% confidence interval (CI) −2.51 to 2.39; participants = 174; moderate-certainty evidence). We downgraded the evidence certainty by one level due to study limitations. Aquablation may also result in similar quality of life when compared to TURP (MD 0.27, 95% CI −0.24 to 0.78; participants = 174, low-certainty evidence). We downgraded the evidence certainty by two levels due to study limitations and imprecision. Aquablation may result in little to no difference in major adverse events (risk ratio (RR) 0.84, 95% CI 0.31 to 2.26; participants = 181, very low-certainty evidence) but we are very uncertain of this finding. This would correspond to 15 fewer major adverse events per 1000 participants (95% CI 64 fewer to 116 more). We downgraded the evidence certainty by one level for study limitations and two levels for imprecision.

Secondary outcomes

Up to 12 months, Aquablation may result in little to no difference in retreatments (RR 1.68, 95% CI 0.18 to 15.83; participants = 181, very low-certainty evidence) but we are very uncertain of this finding. This would correspond to 10 more retreatments per 1000 participants (95% CI 13 fewer to 228 more). We downgraded the evidence certainty by one level due to study limitations and two levels for imprecision.

Aquablation may result in little to no difference in erectile function as measured by International Index of Erectile Function questionnaire Erectile Function domain compared to TURP (MD 2.31, 95% CI −0.63 to 5.25; participants = 64, very low-certainty evidence), and may cause slightly less ejaculatory dysfunction than TURP, as measured by Male Sexual Health Questionnaire for Ejaculatory Dysfunction (MD 2.57, 95% CI 0.60 to 4.53; participants = 121, very low-certainty evidence). However, we are very uncertain of both findings. We downgraded the evidence certainty by two levels due to study limitations and one level for imprecision for both outcomes.

We did not find other prospective, comparative studies comparing Aquablation to TURP or other procedures such as laser ablation, enucleation, or other minimally invasive therapies.