THE INITIAL findings of the WATER III trial, presented at the European Association of Urology (EAU) Congress 2025 in Madrid, demonstrate that Aquablation, a robot-assisted waterjet technique, is as a safe option for patients with benign prostatic hyperplasia (BPH) and large prostates (80–180 mL), and is able to provide both symptom relief and preserved sexual function.
BPH, which affects over half of men aged 50+ and 80% of those over 70, commonly causes urinary symptoms that impair quality of life such as a frequent need to urinate, a weak urine stream, and leaking or dribbling of urine. Surgical interventions like laser therapy often compromise sexual function, particularly ejaculation, creating a critical need for alternatives. On the other hand, a high-pressure water jet to operate on an enlarged prostate has similar outcomes to laser surgery and can be performed with robot assistance, reducing waiting times.
The WATER III trial aimed to investigate if using high-pressure waterjet surgery can preserve sexual function in patients with large prostates (80–180 mL). The multicentre trial enrolled 202 men from Germany and the UK with large prostates (between 80 – 180 mL), randomising 98 participants to Aquablation and 88 to Holmium/Thulium laser surgery (HoLEP/ThuLEP).
At three-month follow-up, retrograde ejaculation occurred in 15% of Aquablation patients versus 77% with lasers (p<0.001). Urinary incontinence rates were halved (9% vs 20%), while symptom improvement (assessed using the International Prostate Symptom Score) and short-term safety profiles matched across groups. Among sexually active participants (n=89), Aquablation users reported higher satisfaction, with 85% maintaining antegrade ejaculation. The procedure’s robotic precision reduced surgical complexity, potentially expanding access compared to laser techniques requiring steep learning curves.
These findings position waterjet surgery as a transformative option for BPH patients prioritising sexual function. Clinicians should consider discussing this minimally invasive approach, particularly for younger men or those concerned about fertility. Future research must address the trial’s three-month follow-up limitation by tracking long-term outcomes, including prostate-specific antigen levels and urinary flow rates. Expanding studies to include patients with chronic urinary retention will clarify broader applicability.
Reference
Ritter M et al. WATER III: Aquablation vs. Transurethral Laser Enucleation of Large Prostates (80 – 180mL) in Benign Prostatic Hyperplasia (WATER III). EAU Annual Congress, 21-24 March, 2025.
