Thulium Fiber Laser En-bloc Resection vs Conventional Transurethral Resection of Non-muscle-invasive Bladder Cancer

Study Overview
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Brief Summary
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Ongoing efforts aim at overcoming the challenges of conventional transurethral resection of bladder tumor (TURBT) such as the high recurrence rate, difficulty of pathologic interpretation and complications including wall injury. Possible advantages may have en bloc resection of bladder tumor which was previously shown to be effective and safe technique. Use of novel thulium-fiber laser may also provide additional safety and efficacy of the resection. Objective. To prospective assess the safety and efficacy of Thulium-fiber en bloc resection of bladder tumor (Tm-fiber-ERBT) compared to TURBT.

Detailed Description
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En bloc resection of bladder tumor (ERBT) was first employed by Kawada T. et al. in 1997. The technique showed promising results in terms of safety and tumor staging. Development of laser surgery and emergence of the holmium (Ho:YAG) and later thulium (Tm:YAG) lasers in the 1990s enabled laser ERBT with subsequent studies demonstrating high efficacy and safety of the new techniques. Ho:YAG and Tm:YAG ERBT have distinct advantages over conventional TURBT such as the complete absence of the obturator nerve reflex and hence, lower risks of perforation or bleeding as well as a higher quality specimens for pathologic examination, due to lack of the cautery effect. Recently, a new type of thulium laser was developed - that allows to decrease the penetration depth less than 0.15 mm, which is two times less than that of Tm:YAG. Another advantage is the decreased carbonization compared to Tm:YAG due to better water absorption of laser energy. All these aspects make Tm:YAG a precise tool that may improve the resection quality resulting in better management. Data on laser ERBT of NMIBC with Tm:YAG is limited and that on Tm-fiber laser ERBT is absent altogether. The investigators hypothesized that Tm-fiber laser ERBT would result in a lower probability of adverse events and better recurrence-free survival compared to conventional TURBT.

Official Title
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Safety and Short-term Oncological Outcomes of Thulium Fiber Laser En-bloc Resection of Non-muscle-invasive Bladder Cancer

Conditions
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Bladder Cancer

Intervention / Treatment
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* Procedure: Thulium fiber laser en-bloc resection of non-muscle-invasive bladder cancer
* Procedure: Transurethral resection of non-muscle-invasive bladder cancer


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: • Primary Ta or T1 bladder cancer (NMIBC) Exclusion Criteria: • Pure carcinoma in situ

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: TURBT<br>A step-by-step resection of a tumor. Firstly, visible tumor is resected, then resection continues to the apparently normal mucosa on the border of the tumor, than resection of the muscle layer at the base of the tumor is performed until normal muscle fibers are visible. | Procedure: Transurethral resection of non-muscle-invasive bladder cancer<br>* After cystoscopy and determining tumor topography, a step-by-step resection of a tumor is done. Firstly, visible tumor is resected, then resection continues to the apparently normal mucosa on the border of the tumor, than resection of the muscle layer at the base of the tumor is performed until normal muscle fibers are visible.<br>|
| Experimental: Tm-fiber ERBT<br>A circumferential incision around the tumor is made in the visually intact bladder mucosa. After that, the incision is continued deeper into the muscular layer. Than the surgeon resects the base of the tumor with the muscular layer using traction and incisions of the muscle fibers. | Procedure: Thulium fiber laser en-bloc resection of non-muscle-invasive bladder cancer<br>* After cystoscopy and determining tumor topography, a circumferential incision around the tumor is made in the visually intact bladder mucosa (approximately 10 mm from the edges of the tumor). It allows for accurate morphological evaluation of the surgical margin. After that, the incision is continued deeper into the muscular layer. Having identified the layer, the surgeon resects the base of the tumor with the muscular layer using traction and incisions of the muscle fibers. Making incisions in the muscular layer requires precision, a full bladder and adequate guidance with visualization techniques. Traction may be employed with the help of the tip of the resectoscope or working element. After complete tumor resection, local hemostasis was performed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Recurrence-free survival rate | Absence of cancer at the site of previous resection on histological examination after re-biopsy | 3 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Detrusor presence in the specimen | The presence of muscle fibers in specimens on histological investigation | 1 day after the surgery | 
| Complications | Rate of postoperative complications, their severity according Clavien-Dindo score | up to 1 year |