While initial guidelines recommended Rezūm for prostates less than 80 mL, recent studies have demonstrated its efficacy and safety in larger prostates. Water Vapor Thermal Therapy (WVTT), Rezūm, is a minimally invasive therapy that uses water vapor to ablate benign prostatic tissue. This study aims to present the prospective, multi-center outcomes of the largest cohort of prostates ≥80 mL treated with Rezūm.

This study involved a prospective, Rezum registry which collated information from two high-volume centers between April 2019 and August 2024. Baseline medical histories, uroflowmetry (Qmax, PVR), and validated questionnaires (IPSS, IPSS QoL, BPHII, IIEF-15, MSHQ-EjD) were recorded. The main outcomes assessed included symptom scores, functional improvement, and safety at baseline, 6, 12 and 24 months.

A total of 259 patients with a prostate volume ≥80 mL were treated with Rezūm. The median prostate volume was 105 mL (interquartile range 91–122.5 mL), with 207 patients (81.2%) exhibiting a median lobe. A history of urinary retention was noted in 86 patients (33.6%). On average, 13.2 injections (±3.8) were administered per procedure, which lasted an average of 6.9 minutes (±10.1). The IPSS improved from 21.8 (n=212) at baseline to 9.1 at 6 months (n=131), 6.6 at 12 months (n=107), and 5.7 at 24 months (n=68). At baseline, the maximum urinary flow rate (Qmax) was 8.2 mL/s (n=198), increasing to 14.6 mL/s at 6 months (n=45), 14.1 mL/s at 12 months (n=46), and 14.9 mL/s at 24 months (n=33). Post-void residual (PVR) volume at baseline was 132.5 mL (n=196), decreasing to 72 mL at 6 months (n=42), 60 mL at 12 months (n=93), and 90 mL at 24 months (n=38). The IPSS quality of life (IPSS QoL) score decreased from 4.5 (n=212) at baseline to 1.4 at 6 months (n=131), 1.65 at 12 months (n=107), and 1.1 at 24 months (n=68). The BPHII decreased from 7.5 at baseline (n=171) to 3.3 at 6 months (n=86), 2.9 at 12 months (n=65), and 2.3 at 24 months (n=35). There was no significant difference noted in sexual function as measured by IIEF and MSHQ.

Rezūm water vapor therapy appears to be both effective and well-tolerated in men with significantly enlarged prostates (≥80 mL), including those with challenging anatomy such as a median lobe and those with a history of urinary retention.  Symptom improvement was both rapid and sustained over time. The International Prostate Symptom Score (IPSS) improved from a baseline of 21.8 to  5.7 at 24 months. Maximum urinary flow rate (Qmax) also improved significantly, rising from 8.2 mL/s at baseline to  14.9 mL/s at 24 months. Similarly, post-void residual volume (PVR) decreased from 132.5 mL at baseline to 90 mL at 24 months. Quality of life, as assessed by the IPSS QoL score, also improved dramatically The BPH Impact Index (BPHII) followed a similar trend, decreasing from 7.5 to 2.3 by 24 months. Importantly, sexual function was preserved, with no significant changes observed in IIEF or MSHQ scores.

These findings suggest that Rezūm is a promising minimally invasive treatment option even for patients with large prostates and complex anatomy, offering durable symptom relief without compromising sexual health. Significant improvements were observed in urinary symptoms and quality of life, with minimal impact on sexual function.