JU INSIGHT Aquablation Lower Urinary Tract Symptoms Due to Benign Prostatic Hyperplasia: Final WATER II Results

By: Naeem Bhojani, MD, University of Montreal Hospital Center, Université de Montréal, Quebec, Canada; Mo Bidair, MD, San Diego Clinical Trials, California; Eugene Kramolowsky, MD, Virginia Urology, Richmond; Mihir Desai, MD, University of Southern California, Los Angeles; Leo Doumanian, MD, University of Southern California, Los Angeles; Kevin C. Zorn, MD, University of Montreal Hospital Center, Université de Montréal, Quebec, Canada; Dean Elterman, MD, University of Toronto University Health Network, Ontario, Canada; Ronald P. Kaufman Jr, MD, Albany Medical College, New York; Gregg Eure, MD, Urology of Virginia, Virginia Beach; Gopal Badlani, MD, Wake Forest School of Medicine, Winston-Salem, North Carolina; Mark Plante, MD, University of Vermont Medical Center, Burlington; Edward Uchio, MD, VA Long Beach Healthcare System, California; Greg Gin, MD, VA Long Beach Healthcare System, California; Ryan Paterson, MD, University of British Columbia, Vancouver, Canada; Alan So, MD, University of British Columbia, Vancouver, Canada; Claus Roehrborn, MD, UT Southwestern Medical Center, Dallas, Texas; Jay Motola, MD, Icahn School of Medicine at Mount Sinai, New York, New York; Steven Kaplan, MD, Icahn School of Medicine at Mount Sinai, New York, New York; Mitch Humphreys, MD, Mayo Clinic Arizona, Scottsdale | Posted on: 20 Jul 2023

Bhojani N, Bidair M, Kramolowsky E, et al. Aquablation therapy in large prostates (80-150 mL) for lower urinary tract symptoms due to benign prostatic hyperplasia: final WATER II 5-year clinical trial results. J Urol. 2023;210(1):143-153.

Study Need and Importance

Men suffering from benign prostatic hyperplasia with large prostates (>80 mL) traditionally have few treatment options. Limitations of those options can pose high postoperative morbidity risks to the patient. In comparison, Aquablation has shown consistent and durable outcomes with low associated morbidity in a randomized study compared to transurethral resection of the prostate (TURP) in prostates <80 mL. The importance of this study is to demonstrate if Aquablation can produce similar results in prostates larger than 80 mL.

What We Found

The study successfully met its safety and efficacy performance goals at 3 months, based on TURP outcomes typically done for smaller prostates. Mean prostate volume was 107 mL (range 80-150) at baseline. Patient symptoms showed a significant and sustained improvement with the mean (SD) International Prostate Symptom Score of 22.6 (6.4) at baseline decreasing to 6.8 (4.6) at 5 years, resulting in a change score of 15.9 (7.7; P < .001; see Figure). Uroflowmetry measurements also demonstrated significant improvement with the mean (SD) maximum urinary flow rate increasing from 8.6 (3.4) to 17.1 (9.8) mL/s at 5 years, resulting in a change score of 9.2 (11.1) mL/s (P < .001). A regression analysis evaluating change in PSA as a function of baseline PSA across all time points out to 5 years resulted in a 50% reduction. Freedom from a secondary benign prostatic hyperplasia procedure at 5 years was 96.3% based on the Kaplan-Meier curve.

Figure. Longitudinal International Prostate Symptom Score (IPSS), IPSS quality of life (QOL), maximum urinary flow (Qmax), post-void residual (PVR), Male Sexual Health Questionnaire−Ejaculatory Dysfunction (MSHQ-EjD), and International Index of Erectile Function (IIEF-5) outcomes. CI indicates confidence interval.

Limitations

The study was a single-arm prospective study in large prostates with no comparison group. However, Aquablation was previously studied in a randomized trial comparing TURP outcomes in smaller glands with similar results.

Interpretation for Patient Care

Aquablation has shown excellent reproducible clinical outcomes regardless of prostate size (up to 150 mL) with a very low surgical re-treatment rate at 5 years especially for men wanting to preserve continence, erectile function, and improved ability to maintain ejaculatory function.