Predictors of Trifecta Achievement After HoLEP

This study aims to identify preoperative and perioperative variables influencing trifecta achievement in HoLEP surgery and to determine the predictive value of these variables.

Based on the analysis of the collected data, it is anticipated that one or more variables will show a statistically significant association with trifecta outcomes.

Additionally, the study seeks to evaluate the predictive value of these variables for successfully reaching the trifecta. Based on our analysis of the collected data, we expect that one or more of these variables will show a statistically significant association with trifecta outcomes.

Lower urinary tract symptoms (LUTS) are defined by the International Continence Society (ICS) as a constellation of complaints originating from lower urinary tract organs, such as the bladder, prostate, urethra, adjacent pelvic floor muscles, and distal ureters. A large-scale epidemiological study has shown that the prevalence of LUTS in men over 40 years of age is 62%, increasing with advancing age. LUTS in older men are most commonly attributed to benign prostatic obstruction (BPO), and autopsy series have reported benign prostatic hyperplasia (BPH) histology in 60-80% of cases. All patients who are refractory to medical treatment or present with complications are candidates for surgical therapy.

In selecting the surgical approach, patient comorbidities, bladder neuromuscular function, and prostate volume are key determinants. Transurethral laser enucleation techniques (HoLEP, ThuLEP) are non-inferior to conventional methods in BPO surgery and even demonstrate advantages in patients in whom antiplatelet or anticoagulant therapy cannot be discontinued; accordingly, they have been incorporated into the European Association of Urology guidelines.

"Trifecta" refers to the achievement of three ideal and measurable conditions within a defined perioperative or postoperative period, representing surgical success from both the patient's and the surgeon's perspectives (functional outcomes and complications). As trifecta is a relatively new concept in BPO surgery, there are currently insufficient studies to establish universally accepted criteria. Moreover, because the factors contributing to trifecta achievement and their relative impact remain unclear, this clinical study has been designed.

Following approval by the local ethics committee, data of all patients treated with HoLEP between March 2026 and April 2028 will be prospectively collected.

All male patients with an indication for surgical treatment, and without clinically proven prostate cancer, bladder cancer, or neurogenic LUTS, will be included in the study. Preoperatively, all patients will undergo non-invasive laboratory and imaging evaluations, including complete blood count, routine biochemistry, urinalysis, urine culture, total PSA, uroflowmetry with post-void residual measurement (PVR), and ultrasonography or magnetic resonance imaging when clinically indicated. Standardized international questionnaires will be used for symptom assessment.

Postoperative complications will be classified according to the Clavien-Dindo grading system. All patients will be evaluated postoperatively at 1, 3, 6, and 12 months, and annually thereafter, using uroflowmetry with PVR, total PSA, renal function tests, and international symptom questionnaires.

In our study, trifecta was defined as the simultaneous fulfillment of all of the following criteria at postoperative month 3: absence of complications greater than Clavien-Dindo grade II, absence of urinary incontinence, and at least a 30% reduction in the International Prostate Symptom Score (IPSS).

The primary endpoint of the study was defined as trifecta achievement at postoperative month 3 following HoLEP. To identify factors predicting trifecta success, analyses were planned using a binary outcome (yes/no). The effects of preoperative and perioperative variables on trifecta achievement will be evaluated using logistic regression models. Variables found to be significant in univariable analyses or considered clinically relevant will be included in the multivariable model. Model predictive performance will be assessed using the area under the receiver operating characteristic curve (AUC), and results will be reported as odds ratios (ORs) with 95% confidence intervals (CIs). All statistical analyses will be two-sided, and a p-value \<0.05 will be considered statistically significant.

As the study was designed as a multivariable predictive model, the minimum sample size was calculated for multivariable logistic regression using the Riley framework with the pmsampsize package in R Studio (version 4.5.1). Based on the literature, trifecta prevalence was assumed to be 63%, approximately 10 parameters were expected to be included in the model, and a Cox-Snell R² of 0.15 was assumed. Accordingly, the minimum required sample size was calculated as 549 patients. Considering potential missing data and loss to follow-up, a 10% inflation was applied, resulting in a planned target sample size of approximately 604 patients.