WATER vs WATER II: Comparing Aquablation Therapy for Benign Prostatic Hyperplasia in 30cc-80cc and 80cc-150cc Prostates.

Surgical options, especially those with short learning curves are limited when treating large prostates for lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). Aquablation (AQUABEAM System, PROCEPT BioRobotics, Inc. , USA) could be this novel tool with global reproducibility, independent of prostate volume. We compared the outcomes of Aquablation in 30cc to 80cc prostates with those in 80cc to 150cc.

WATER (NCT02505919) is a prospective, double-blind, multicenter, international clinical trial comparing Aquablation and TURP for the treatment of LUTS/BPH in prostates between 30cc and 80cc. WATER II (NCT03123250) is a prospective, multicenter, single-arm international clinical trial of Aquablation in prostates between 80cc and 150cc. We compare baseline parameters and 12-month outcomes in 116 WATER (W-I) and 101 WATER II (W-II) study subjects. Students' t-test or Wilcoxon tests were used for continuous variables and Fisher's test for binary variables.

Mean operative time was 33±17 and 37±13 minutes, in W-I and W-II respectively. Actual treatment time was 4 and 8 min in W-I and W-II respectively. Mean change in IPSS was substantial averaging (at 1 year) 15.1 in W-I and 17.1 in W-II (p=.6046). By 3 months, Clavien-Dindo grade 2 or higher events occurred in 19.8% of W-I subjects and 34.7% of W-II subjects (p=.4680).

Aquablation clinically normalizes outcomes between patients with a 30cc to 80cc prostate and patients with an 80cc to 150cc prostate treated for LUTS/BPH with an expected increase in the risk of complication. Long-term outcomes of procedure durability are needed.

BJU international. 2019 Oct 09 [Epub ahead of print]

David-Dan Nguyen, Neil Barber, Mo Bidair, Peter Gilling, Paul Anderson, Kevin C Zorn, Gopal Badlani, Mitch Humphreys, Steven Kaplan, Ronald Kaufman, Alan So, Ryan Paterson, Larry Goldenberg, Dean Elterman, Mihir Desai, Jim Lingeman, Claus Roehrborn, Naeem Bhojani

McGill University, Faculty of Medicine, Montreal, Quebec, Canada., Frimley Park Hospital, Urology, Frimley, Surrey, UK., San Diego Clinical Trials, San Diego, California, United States., Bay of Plenty District Health Board Clinical School, Urology, Tauranga, New Zealand., Royal Melbourne Hospital, Urology, Melbourne, Victoria, Australia., CHUM, Urology, Montreal, Quebec, Canada., Wake Forest School of Medicine, Urology, Winston-Salem, North Carolina, United States., Mayo Clinic, Department of Urology, 5777 East Mayo Blvd, Phoenix, Arizona, United States., Department of Urology Mount Sinai Hospital, New York, United States., Albany Medical College, Division of Urology, Albany, New York, United States., University of british columbia, Uoroligic sciences Vancouver British Columbia Canada, Vancouver, Canada., BC Cancer Agency Vancouver Island Centre, Victoria, British Columbia, Canada., University of british Columbia, Urologic Sciences, Vancouver, British Columbia, Canada., University of Toronto, Division of Urology, 399 Bathurst Street MP-8-317, Toronto, Ontario, Canada., USC Institute of Urology, University of Southern California, Urology, Los Angeles, California, United States., Methodist Hospital Institute for Kidney Stone Disease, Indianapolis, Indiana, United States., UT Southwestern Medical Centre, Urology, United States., University of Montreal Hospital Center, 900 St. Denis; Pavilion R, R08.474, Montréal, Québec, H2X 0A9.