Aquablation for BPH in Large Prostates (80-150cc): 6-Month Results From the WATER II Trial.

Objective To present 6-month safety and effectiveness data from a multicentre prospective study of aquablation in men with lower urinary tract symptoms (LUTS) attributable to benign prostatic hyperplasia (BPH) with prostate volumes between 80 and 150 mL. Methods Between September and December 2017, 101 men with LUTSattributable to BPHwere prospectively enrolled at 16 centres in Canada and the USA. Results The mean prostate volume was 107 mL. The mean length of hospital stay after the aquablation procedure was 1.6 days (range: same day to 6 days). The primary safety endpoint (Clavien-Dindo grade 2 or higher or any grade 1 event resulting in persistent disability) at 3 months occurred in 45.5% of men, which met the study design goal of < 65% (P < 0.001). At 6 months, 22% of the patients had experienced a Clavien-Dindo grade 2, 14% a grade 3 and 5% a grade 4 adverse event. Bleeding complications requiring intervention and/or transfusion were recorded in eight patients prior to discharge and in six patients after discharge. The mean International Prostate Symptom Score improved from 23.2 +/- 6.3 at baseline to 6.7 +/- 5.1 at 3 months, meeting the study's primary efficacy endpoint goal (P < 0.001). The maximum urinary flow rate increased from 8.7 to 18.8 mL/s (P < 0.001) and post-void residual urine volume decreased from 131 at baseline to 47 at 6 months (P < 0.0001). At 6 months, prostate-specific antigen concentration reduced from 7.1 +/- 5.9 ng/mL at baseline to 4.0 +/- 3.9 ng/mL, a 44% reduction. Conclusions Aquablation is safe and effective in treating men with larger prostates (80-150 mL), without significant increase in procedure or resection time.