ABSTRACT
BACKGROUND: Surgical options are limited when treating large (>80 cm3) prostates for lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). Open simple prostatectomy remains the most common procedure performed for large prostates. There is a need for novel surgical approaches with shorter learning curves and effective treatment. Aquablation could be this novel tool. OBJECTIVE: To compare the outcome of Aquablation for 30-80-cm3 prostates with the outcome for 80-150-cm3 prostates at 2-yr follow-up. DESIGN SETTING AND PARTICIPANTS: We used data from two trials. WATER is a prospective, double-blind, multicenter, international clinical trial comparing the safety and efficacy of Aquablation and transurethral resection of the prostate in the treatment of LUTS/BPH in men aged 45-80 yr with a prostate of 30-80â¯cm3. WATER II is a prospective, multicenter, single-arm international clinical trial of Aquablation in men with a prostate of 80-150â¯cm3. INTERVENTION: Aquablation, an ultrasound-guided, robotically executed waterjet ablative procedure. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We compared 24-mo outcomes between 116 WATER and 101 WATER II study subjects. Student's t test or a Wilcoxon test was used to compare continuous variables and Fisher's test for categorical variables. RESULTS AND LIMITATIONS: The International Prostate Symptom Score (IPSS) reductions at 24 mo was 14.5 points for WATER and 17.4 points for WATER II (pâ¯=â¯0.31). At baseline, the maximum urinary flow rate (Qmax) was 9.4 and 8.7â¯cm3/s in WATER and WATER II, improving to 20.5 and 18.2â¯cm3/s, respectively (pâ¯=â¯0.60) at 24 mo. Improvements in both IPSS and Qmax were immediate and sustained throughout follow-up. At 2â¯yr, the surgical retreatment rate was 4% in WATER and 2% in WATER II. CONCLUSIONS: Aquablation is effective in patients with a prostate of 30-80â¯cm3 and patients with a prostate of 80-150â¯cm3 treated for LUTS/BPH, with comparable outcomes in both groups. It has low complication and retreatment rates at 2â¯yr of follow-up, with durable improvements in functional outcome. PATIENT SUMMARY: Outcomes of Aquablation for both small-to-moderately-sized and large prostates are similar and sustainable at 2â¯yr of follow-up.
ABSTRACT
OBJECTIVE: To compare the outcomes of Aquablation in 30-80 mL prostates with those in 80-150 mL prostates. Surgical options, especially 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., Redwood City, CA, USA) could solve this issue with global reproducibility, independent of prostate volume. PATIENTS AND METHODS: Waterjet Ablation Therapy for Endoscopic Resection of prostate tissue (WATER [W-I]; NCT02505919) is a prospective, double-blind, multicentre, international clinical trial comparing Aquablation and transurethral resection of the prostate (TURP) for the treatment of LUTS/BPH in prostates between 30 and 80 mL. WATER II (W-II; NCT03123250) is a prospective, multicentre, single-arm international clinical trial of Aquablation in prostates between 80 and 150 mL. We compare baseline parameters and 12-month outcomes in 116 W-I and 101 W-II study patients. Students' t-test or Wilcoxon tests were used for continuous variables and Fisher's test for binary variables. RESULTS: The mean (SD) operative time was 33 (17) and 37 (13) min in W-I and W-II, respectively. Actual treatment time was 4 and 8 min in W-I and W-II, respectively. The mean change in the International Prostate Symptom Score was substantial averaging (at 12 months) 15.1 in W-I and 17.1 in W-II (P = 0.605). By 3 months, Clavien-Dindo grade ≥II events occurred in 19.8% of W-I patients and 34.7% of W-II patients (P = 0.468). CONCLUSION: Aquablation clinically normalises outcomes between patients with 30-80 mL prostates and patients with 80-150 mL prostates treated for LUTS/BPH, with an expected increase in the risk of complications in larger prostates. Long-term outcomes of procedure durability are needed.
