SIU 2018: BPH Panel: Enucleation Techniques: Aquablation

Seoul, South-Korea ( Peter Gilling, MD gave an overview of the impressive and novel aquablation technique for prostate adenomas in benign prostatic hyperplasia (BPH). Aquablation is a semi-automatic technique using robotic-assisted technology. It has a touch screen interface to map areas of ablation, and it provides accurate conformal treatment, directed by the surgeon. The tissue is removed acutely and rapidly by waterjet, and the ablation is heat free.

In aquablation, hemostasis can be achieved with either a low powered laser that is integrated to the system, or with electrocautery, or more commonly with catheter traction either in the prostatic fossa or in the bladder with over-inflation of the balloon, with the complimentary use of a penile traction device. 

The first proof of concept publication was in 2015, demonstrating the outcome of this procedure performed in 8 beagles. This showed minimal bleeding, with bladder perforation in 2, with significant extravasation in one.1 The first human study began in 2013 and published in 2016. A total of 15 patients were treated with a procedure time of 48 minutes, and a hospital stay of 1.8 days, and no serious adverse effects. 2 Later, a study on the 1-year follow-up of patients treated with this novel technique was published, with data on 21 patients, demonstrating a 32% prostate volume reduction and no serious adverse effects.3

The first pivotal trial which was a randomized controlled trial comparing aquablation to TURP was the WATER trial, published in May 2018.4 In this trial, 181 patients were randomized 2:1 in a non-inferiority design, with 17 multinational sites involved (12 in the US) with blinded assessments. All prostates were less than 80 grams, and the primary endpoints were of safety and efficacy. The WATER trial showed that aquablation was non-inferior to TURP regarding IPSS score, urinary flow, and post-void residual. Regarding safety, aquablation had a lower rate of Clavien Dindo grade 1 complications but similar grade 2 complications as TURP.

The WATER II trial attempted to copy the WATER trial, with the only difference being that all the prostates are larger, measuring between 80-150 cc. Overall 101 patients were recruited, with a mean prostate size of 107.4 cc, taking place at 13 US centers, and 3 Canadian centers.5 The results demonstrated that 82% of the patients had spinal anesthesia, with a mean aquablation time of 8 minutes! And the average number of passes being 1.8. Bladder neck traction for hemostasis was performed in 98 / 101 patients for a mean duration of 18 hours, and a mean catheter duration of 94 hours.  None of the patients required cautery for hemostasis. The mean length of hospital stay was 1.6 days. Within three months there was an impressive 44% prostate volume reduction.

Dr. Gilling summarized his talk and stated that aquablation is a most attractive modality demonstrating outcomes at least as good as TURP, if not better, with a good safety profile, being able to treat both small and large prostate adenomas, with a short procedure time and minimal length of hospital stay.

Presented by: Peter J. Gilling, MD, Tauranga, New Zealand

1. Faber K et al. J Urol 2015
2. Gilling P et al.  BJU Int. 2016
3. Gilling P et al. J. Urol 2017
4. Giliing P et al. J. Urol 2018
5. Desai M et al. BJU Int. 2018

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre  Twitter: @GoldbergHanan at the 38th Congress of the Society of International Urology - October 4- 7, 2018 - Seoul, South Korea