Water vapor thermal therapy for treatment of lower urinary tract symptoms due to large benign prostatic hyperplasia (≥ 80 g)

Abstract

Introduction: Water vapor thermal therapy (WVTT; REZUM™; Boston, USA) offers symptom relief with reduced risks of complications in patients with lower urinary tract symptoms (LUTS) related to benign prostatic obstruction (BPO). WVTT therapy has been validated in the pivotal study in men with smaller prostates (< 80 cc). Yet, its feasibility for larger prostates (≥ 80 cc) remains underexplored.

Methods: This retrospective study assessed WVTT efficacy and safety in 131 patients with symptomatic BPH treated between January 2022 and March 2024. Patients were categorized based on prostate size: smaller prostates (SP) (< 80 cc) and larger prostates (LP) (≥ 80 cc). Baseline characteristics, treatment specifics, and post-procedure outcomes-including retreatment rates, symptom scores, and adverse events (AEs)-were recorded. All patients who required surgical retreatment underwent Holmium laser enucleation of the prostate (HoLEP). Statistical analyses compared results between groups over 6- and 12-month follow-up periods.

Results: Among the 131 patients, 48 (37%) had LP, with a median volume of 93 cc (Interquartile range (IQR) 88-110). Patients with LP experienced more non-serious AEs, primarily hematuria (p = 0.001), although serious AEs were similar across groups and limited to urinary retention (p = 0.35). At 6 months postoperatively, LP patients had a higher PVR (42 mL(IQR 21-75) vs. 21 mL (IQR2-40); p = 0.032), though this resolved by 12 months. No significant differences were observed between the groups in IPSS, maximum flow rate (Qmax), or erectile function (IIEF-5) scores at either follow-up point. Medical retreatment rates at 12 months were similar (LP: 4% vs. SP: 7%; p = 0.39), as were surgical retreatment rates (LP: 2% vs. SP: 2%; p = 0.51). Ejaculatory function was largely preserved in both groups (LP: 96%, SP: 95%).

Conclusion: WVTT therapy in LP is associated with a higher risk of minor post-operative AEs, with similar functional outcomes at one year compared to SP. Longer follow-up studies are needed to compare the durability of treatment in LP.

Keywords: Benign prostatic obstruction; Large prostates; Lower urinary tract symptoms; Minimally invasive surgical therapy; Water vapor thermal therapy.