Minimally Invasive Prostate Interventions Registry (MIST Study)

Benign prostatic obstruction (BPO) secondary to benign prostatic hyperplasia (BPH) is a prevalent cause of lower urinary tract symptoms (LUTS) in aging men. Minimally invasive surgical therapies (MIST) have become increasingly utilized due to their favorable safety profiles, reduced hospitalization times, preservation of sexual function, and quicker return to normal activities. Despite their growing use, comparative real-world data across MIST modalities remain limited, especially regarding long-term functional outcomes and retreatment rates.

The MIST Registry is an investigator-initiated, non-commercial, multicenter, observational cohort study coordinated by the Department of Urology at Necmettin Erbakan University. The aim is to systematically collect high-quality clinical data from centers using a standardized REDCap electronic data capture system. The registry includes patients treated with any guideline-supported minimally invasive prostate intervention, including Rezum, UroLift, Aquablation, prostatic artery embolization (PAE), iTind, TPLA, TUNA, and TUMT. These procedures are performed as part of routine clinical care and not assigned by the study.

Data collection includes demographics, comorbidities, prior BPO treatments, LUTS medication history, PSA levels, prostate volume, presence and size of median lobe, uroflowmetry parameters, PVR, patient-reported outcomes (IPSS, QoL, IIEF-5, MSHQ-EjD), and urodynamic findings when available. Intraoperative data include type of MIST technique, procedure duration, device usage, energy delivery parameters, imaging guidance, estimated blood loss, and intraoperative complications. Postoperative outcomes include catheterization duration, early complications within 30 days, rehospitalization, urinary retention, infections, and device-related events. Complications are categorized according to the Clavien-Dindo classification, and bladder injury can be scored using the BICEP system where relevant.

Follow-up assessments occur at 1, 3, 6, 12, 24, and 36 months, with optional long-term evaluations at 72 months. Outcomes assessed include symptom scores, Qmax, PVR, PSA, medication changes, and any surgical or minimally invasive reinterventions. Statistical analyses will include descriptive summaries, longitudinal comparisons, multivariable modeling to identify predictors of success or failure, and Kaplan-Meier estimates of reintervention-free survival.

The registry is designed to generate real-world evidence that reflects routine clinical practice across diverse populations and healthcare systems. Findings are expected to inform patient selection, refine procedural decision-making, improve counseling on expected outcomes, and support comparative effectiveness research among emerging minimally invasive prostate treatments.

• No intervention (Other): Participants receive standard-of-care minimally invasive prostate interventions determined by their treating clinicians. The study does not assign or alter any treatment; it only observes outcomes.

Primary outcomes

• Change in International Prostate Symptom Score (IPSS) [Baseline; 1, 3, 6, 12, 24, 36, and optional 72 months post-procedure]: IPSS is a validated 0-35 questionnaire assessing lower urinary tract symptoms. Lower scores indicate symptom improvement. Change from baseline will be evaluated at each follow-up visit using patient-reported scores collected via standardized REDCap forms.
• Change in maximum urinary flow rate (Qmax) [Baseline; 1, 3, 6, 12, 24, 36, and optional 72 months post-procedure]: Qmax (mL/s) is measured by uroflowmetry at each clinical visit. Improvement in urinary flow represents treatment effectiveness. Change from baseline will be analyzed longitudinally.
• Change in quality of life (QoL) score (IPSS subscore) [Baseline; 1, 3, 6, 12, 24, 36, and optional 72 months post-procedure]: QoL score ranges from 0-6. Lower scores reflect improved quality of life. Change from baseline is measured using the IPSS-QoL item collected through REDCap.

Secondary outcomes

• Change in Post-Void Residual (PVR) volume [Baseline; 1, 3, 6, 12, 24, 36, and optional 72 months]: PVR (mL) measured by ultrasound or bladder scanner. Lower values indicate improved bladder emptying.
• Change in sexual function (IIEF-5 score) [Baseline; 1, 3, 6, 12, 24, 36, 72 months]: IIEF-5 is a validated 5-item erectile function scale (5-25). Higher scores indicate better sexual function.
• Change in ejaculatory function (MSHQ-EjD score) [Baseline; 1, 3, 6, 12, 24, 36, 72 months]: MSHQ-EjD evaluates ejaculatory function and bother. Higher function scores indicate improvement.
• Catheterization duration [Within first 30 postoperative days]: Duration of urinary catheter use (days) recorded after MIST procedures.
• Early postoperative complications (Clavien-Dindo classification) [Within 30 postoperative days]: Complications will be categorized using Clavien-Dindo Grade I-V based on standardized definitions.
• BICEP bladder injury score [During the procedure]: Bladder injury is graded using the validated BICEP classification (0-4b). Applicable only when morcellation or bladder instrumentation is performed.
• Reintervention rate [Up to 72 months]: Need for additional surgery or MIST (TURP, AEEP/HoLEP, repeat MIST, PAE, Aquablation, urethrotomy, implant revisions, etc.).

Sex: Male, ages: 40 Years to any

Inclusion Criteria:

* Male patients aged ≥40 years
* Diagnosis of benign prostatic hyperplasia (BPH) with lower urinary tract symptoms (LUTS) or benign prostatic obstruction (BPO)
* Undergoing a minimally invasive prostate intervention (Rezum, UroLift, Aquablation, PAE, iTind, TPLA, TUNA, TUMT) as part of standard clinical care
* Ability and willingness to attend scheduled follow-up visits
* Prospective participants able to provide written informed consent
* Retrospective cases eligible if data are fully de-identified and inclusion is approved by local ethics/IRB authorities

Exclusion Criteria:

* Active urinary tract infection at the time of treatment
* ASA physical status ≥5
* Prior pelvic radiotherapy resulting in severe bladder dysfunction
* Severe cognitive impairment or inability to participate in follow-up
* Missing essential baseline data (for retrospective entries)
* Patients receiving experimental or investigational prostate devices or therapies outside routine clinical care

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• Selçuk Güven, MD, PhD, Principal investigator, Necmettin Erbakan University