Thulium Laser Enucleation With Bladder Neck Incision for Small-Volume Benign Prostatic Hyperplasia (ThuLEP-BNI)

Benign prostatic hyperplasia (BPH) is a common condition in aging men and may lead to bladder outlet obstruction and lower urinary tract symptoms. In some patients, clinically significant obstruction and symptoms can occur even when prostate volume is relatively small. Small-volume BPH should not necessarily be regarded as a mild condition, because these patients may still experience bothersome symptoms, impaired urinary flow, increased post-void residual urine volume, and bladder outlet obstruction. In this subgroup, obstruction may be related not only to adenomatous enlargement, but also to an elevated, narrow, or fibrotic bladder neck. Surgical treatment of small-volume BPH remains challenging, and the optimal surgical approach has not been clearly established.

This study is a multicentre, randomized, single-blind, four-arm controlled clinical trial designed to evaluate the safety and efficacy of different surgical strategies for patients with small-volume BPH. Eligible male participants aged 40 to 80 years with a prostate volume of less than 30 mL and clinically significant lower urinary tract symptoms or impaired voiding function will be enrolled. A total of 932 participants will be randomly assigned in a 1:1:1:1 ratio to one of four treatment groups: thulium laser enucleation of the prostate combined with bladder neck incision, thulium laser enucleation of the prostate alone, transurethral resection of the prostate (TURP), or transurethral incision of the prostate (TUIP).

The primary objective of the study is to compare the incidence of bladder neck contracture at 6 months after surgery among the treatment groups. Secondary outcomes include safety outcomes and changes in International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax), Visual Analogue Scale (VAS) score, and IPSS response rate at 3 and 6 months after surgery. Exploratory outcomes include changes in post-void residual urine volume and sexual function scores, including the International Index of Erectile Function-5 (IIEF-5) and the Male Sexual Health Questionnaire for Ejaculatory Dysfunction (MSHQ-EjD). Additional exploratory long-term outcomes will be assessed at 12 months after surgery, including delayed bladder neck contracture, maintenance of urinary function, late adverse events, and the need for reintervention.

The study is designed to provide high-quality evidence on the comparative safety and effectiveness of these four surgical approaches in men with small-volume BPH and to help define an optimal surgical strategy for this specific patient population.