WATER vs WATER II 3-Year Update: Comparing Aquablation Therapy for Benign Prostatic Hyperplasia in 30-80 cc and 80-150 cc Prostates

Objective: To compare the outcomes of Aquablation for small-to-moderate (30-80cc) prostates with the outcomes for large (80-150 cc) prostates at 3-year follow up. Methods: WATER is a prospective, double-blind, multicenter, international clinical trial comparing the safety and efficacy of Aquablation and TURP in the treatment of LUTS/BPH in men 45-80 year with a prostate of 30cc-80cc. WATER II is a prospective, multicenter, single-arm international clinical trial of Aquablation in men with a prostate of 80cc-150cc. We compare 36-mo outcomes amongst 116 WATER and 101 WATER II study subjects undergoing Aquablation. Results: International Prostate Symptom Score (IPSS) scores improved from 22.9 and 23.2 at baseline in WATER and WATER II, respectively, to 8.0 and 6.5 at 36-month, with 36-mo reductions of 14.4 and 16.3 points, respectively (P = .247). At baseline, urinary flow rate (Qmax) was 9.4 and 8.7 cc/sec in WATER and WATER II, improving to 20.6 and 18.5 cc/sec, respectively (P = .552) at 36-mo. Improvements in both IPSS and Qmax were immediate and sustained throughout follow-up. At 3 year, 98% and 94% of treated patients were BPH medication-free in WATER and WATER II, respectively (P = .038). At 3yr, 96% and 97% of treated patients were free from surgical retreatment in WATER and WATER II, respectively (P = .613). Conclusions: Three-year follow-up demonstrates that Aquablation therapy leads to sustained outcomes, few irreversible complications, and low retreatment rates for the treatment of LUTS/BPH independently of prostate volume.