Thulium Laser Enucleation With Bladder Neck Incision for Small-Volume Benign Prostatic Hyperplasia

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.

Inclusion criteria

• Male patients aged 40-80 years.
• Diagnosis of benign prostatic hyperplasia (BPH) and scheduled to undergo surgical treatment.
• International Prostate Symptom Score (IPSS) of at least 12, maximum urinary flow rate of no more than 15 mL/s, with a voided volume greater than 150 mL.
• Prostate volume of less than 30 mL measured by transrectal ultrasound (TRUS), calculated as length × width × height × 0.52.
• Ability, as assessed by the investigator, to understand the study requirements and complete the scheduled treatment, follow-up visits, and study-related assessments.

Exclusion criteria

• Inability or refusal to provide written informed consent, or inability to comply with the required follow-up schedule.
• Prostate-specific antigen (PSA) level of 10 ng/mL or higher, unless prostate cancer has been excluded by biopsy.
• Confirmed or suspected prostate or bladder malignancy.
• Pre-existing bladder neck contracture or urethral stricture before surgery.
• Known coagulation disorder or abnormal coagulation function.
• Neurogenic bladder or detrusor underactivity that may affect bladder or urethral sphincter function.
• Benign prostatic hyperplasia (BPH) complicated by acute urinary tract infection, acute prostatitis, or bacterial prostatitis.
• History of prostate surgery, urethral stricture, or neurogenic bladder.
• History of prostate cancer or pelvic radiotherapy.
• Severe cardiovascular disease, pulmonary disease, or other systemic disease that, in the investigator's judgment, would make the patient unable to tolerate surgery.
• Participation in another clinical trial related to benign prostatic hyperplasia (BPH) within 3 months before enrolment.
• Any other condition that, in the investigator's opinion, makes the patient unsuitable for participation in this study.