Green-light laser en bloc resection versus conventional transurethral resection for initial non-muscle-invasive bladder cancer: A randomized controlled trial

Short-term Outcome of RPVBT Combined with Chemotherapy for Patients with Single, < 3 cm, T2 Stage Bladder cancer

BACKGROUND

To investigate the survival outcome of "radical" GreenLight photoselective vaporization of bladder tumor (RPVBT) in conjunction with postoperative chemotherapy for patients with single, < 3 cm in diameter, T2 stage muscle invasive bladder cancer (MIBC).

METHODS

Thirty-eight patients with single, < 3 cm, T2 stage bladder cancer were treated with RPVBT combined with chemotherapy and were included in the RPVBT group. To compare the differences in survival outcome, 80 patients with Ta/T1 bladder cancer and 30 patients with T2 bladder cancer were included as controls. The 80 patients with Ta/T1 bladder cancer underwent GreenLight photoselective vaporization of bladder tumors(PVBT), while 30 patients with T2 bladder cancer underwent radical cystectomy (RC) combined with pelvic lymph node dissection (PLND). Tumor recurrence and death were recorded, and recurrence-free survival (RFS) and overall survival (OS) curves were plotted to compare the survival difference between the RPVBT and control groups.

RESULTS

No significant differences were observed in comorbidities or living habits between the RPVBT and control groups. Blood loss [RPVBT: 20 (IQR10, 20) vs. RC: 100 (IQR90, 150) mL] and postoperative hospital stay [RPVBT: 5.5 (IQR5, 6), vs. RC: 10 (IQR8, 12) days] in the RPVBT group were significantly lower than that in the RC group. Urinary tract infection [RPVBT: 6 (15.8%) vs. PVBT: 14 (17.5%)] and bladder irritation sign [RPVBT: 11 (28.9%) vs. PVBT: 23 (28.8%) ] were the most common short-term complications in the RPVBT group, with no statistical difference between the RPVBT and PVBT group. The median follow-up time for survival endpoints was 22 (16, 27) months for the included patients after surgery. The outcomes of tumor recurrence at 12, 24, and 36 months were 2 (5.3%), 3 (7.9%), and 5 (13.2%) patients in the RPVBT groups, 13 (16.3%) and 3 (10%) patients experienced recurrence in the PVBT and RC groups at 36 months. No significant differences were noted among the three groups (P = 0.778). Additionally, Kaplan-Meier survival analysis revealed no statistically significant differences in RFS (P = 0.791) and OS (P = 0.689) among the three groups.

CONCLUSIONS

Our findings indicate that RPVBT combined with chemotherapy is a simple and feasible treatment option with fewer complications and satisfactory survival outcomes in patients with single, < 3 cm, T2 stage bladder cancer.

Prospective non-randomized comparison of transurethral laser en bloc resection vs. conventional resection of bladder tumors larger than 3 cm

BACKGROUND

En bloc resection of bladder tumor (ERBT) is an established surgical treatment method for patients with non-muscle invasive bladder cancer (NMIBC) in tumors less than 3 cm. Data regarding the efficacy and safety of ERBT on larger than 3 cm tumors are sparse and its efficacy compared to conventional transurethral resection (TURBT) remains unclear. The aim of this study was to prospectively compare the feasibility, safety and oncological outcomes of laser (Tm-fiber) ERBT and TURBT in patients with primary bladder lesions ≥3 cm.

METHODS

A cohort of 45 patients who underwent surgery for primary NMIBC between February 2018 and March 2022 was collected prospectively. There was no randomization. All procedures were performed by two experienced surgeons. Inclusion criteria were as follows: age >18 years, primary Ta or T1 bladder tumor with a diameter of ≥3 cm, no more than 3 tumors and no history of upper tract urothelial carcinoma. Exclusion criteria were carcinoma in situ or invasion into muscle layer (≥T2). ERBT was performed with thulium fiber laser (IPG, Russia). Primary endpoints included efficacy with recurrence-free survival (RFS) at 3, 6 and 12 months. Secondary endpoints were safety parameters, perioperative data and specimen quality (the presence of muscle layer in specimens).

RESULTS

Twenty-eight patients underwent laser ERBT and 17 conventional TURBT. The location and size of the tumors were comparable in both groups. The success rate was 93.3% in the ERBT group with two cases of conversion from ERBT to TURBT. Detrusor muscle was present in 92.8% patients in the ERBT group versus 70.5% in the TURBT group (P=0.04). Obturator nerve reflex was observed only in the TURBT group: 17.6% vs. 0.0% (P=0.02). The frequency of other complications was comparable between the two groups. RFS was not statistically different between the two methods at 3 (93.9% vs. 94.1%, P=0.87), 6 (89.3% vs. 82.3%, P=0.5) and 12 months (89.3% vs. 70.6%, P=0.11).

CONCLUSIONS

Laser ERBT is a feasible and safe procedure to manage bladder tumors larger than 3 cm. While it seems safer than TURBT, its effect on efficacy remains to be assessed in larger trials.

Efficiency of transurethral en-bloc resection vs. conventional transurethral resection for non-muscle-invasive bladder cancer: An umbrella review

BACKGROUND

En-Bloc transurethral resection of bladder tumor (ERBT) was clinically used to resect non-muscle-invasive bladder cancer (NMIBC). However, discrepancies persist regarding the comparisons between ERBT and conventional transurethral resection of bladder tumor (cTURBT).

METHODS

We conducted a comprehensive search in PubMed, Embase, Web of Science, Cochrane Database of Systematic Reviews, and performed manual searches of reference lists to collect and extract data. Data evaluation was carried out using Review Manager 5.4.0, Rx64 4.1.3, and relevant packages.

RESULTS

There were nine eligible meta-analyses and nine eligible RCTs in our study. NMIBC patients undergoing ERBT were significant associated with a lower rate of bladder perforation and obturator nerve reflex compared to those receiving cTURBT. Our pooled result indicated that ERBT and cTURBT required similar operation time. Regarding postoperative outcomes, ERBT demonstrated superior performance compared to cTURBT in terms of detrusor muscle presence, catheterization time, and residual tumor. ERBT exhibited a higher rate of three-month recurrence-free survival (RFS) compared to those receiving cTURBT (p < 0.05; I2 = 0%). In bipolar subgroup, ERBT had a significant better 12-month RFS than cTURBT (p < 0.05; I2 = 0%). Simultaneously, the exclusion of Hybrid Knife data revealed a significant improvement in 12-month RFS associated with ERBT (p < 0.05; I2 = 50%).

CONCLUSION

Using a combination of umbrella review and meta-analysis, we demonstrated that ERBT had better or comparable perioperative outcome and improved 3 and 12 month RFS than cTURBT. We suggest that ERBT maybe a better surgical method for patients with NMIBC compared with cTURBT.

Advances in lasers for the minimally invasive treatment of upper and lower urinary tract conditions: a systematic review

PURPOSE

Technological advancements in laser lithotripsy are expanding into numerous fields of urology, like ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), and benign and malignant soft-tissue treatments. Since the amount of research regarding lasers in urology has grown exponentially, we present a systematic review of the most recent and relevant advances encompassing all lasers used in urological endoscopic treatment.

METHODS

We performed a literature search using PubMed (May 2023) to obtain information about lasers for urological purposes. We included only recent data from published articles between 2021 and 2023 or articles ahead of print.

RESULTS

Lasers are widely used in lithotripsy for ureteric, renal, and bladder stones, benign prostate surgery, and bladder and upper tract tumor ablation. While the holmium (Ho:YAG) laser is still predominant, there seems to be more emphasis on pulse modulation and newer lasers such as thulium fiber laser (TFL) and pulsed Tm:YAG laser.

CONCLUSION

The use of lasers and related technological innovations have shown increasing versatility, and over time have proven to be invaluable in the management of stone lithotripsy, treatment of benign and malignant prostate diseases, and urothelial tumors. Laser endoscopic treatment is heavily based on technological nuances, and it is essential to know at least the basics of these technologies. Ultimately the choice of laser used depends on its availability, cost, surgeon experience and expertise.

En Bloc Versus Conventional Resection of Primary Bladder Tumor (eBLOC): A Prospective, Multicenter, Open-label, Phase 3 Randomized Controlled Trial

BACKGROUND

En bloc transurethral resection of the bladder (eTURB) might improve the surgical management of non-muscle-invasive bladder cancer (NMIBC) in comparison to conventional TURB (cTURB).

OBJECTIVE

To evaluate whether eTURB is superior to cTURB in resection of NMIBC and specimen retrieval.

DESIGN, SETTING, AND PARTICIPANTS

This was a randomized, multicenter trial in patients with up to three cTa-T1 NMIBC tumors of 1-3 cm in size, who were enrolled from January 2019 to January 2022.

INTERVENTION

Participants were randomized 1:1 to undergo eTURB (n = 192) or cTURB (n = 192).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome was the prevalence of detrusor muscle (DM) in the specimen retrieved. Secondary endpoints included bladder perforation, persistent disease at second-look TURB, positive lateral resection margin, positive deep resection margin, operation time, perforation rate, obturator reflex, conversion from eTURB to cTURB, recurrence-free survival, and disease recurrence at 3 mo.

RESULTS AND LIMITATIONS

A total of 384 patients were randomized to undergo eTURB or cTURB. A total of 452 tumors were resected and analyzed for the primary outcome. eTURB was superior to cTURB in retrieval of DM (80.7% vs 71.1%; mixed-model p = 0.01). Bladder perforation (5.6% vs 12%; difference -6.4%; 95% confidence interval [CI] -12.2% to -0.6%) and obturator reflex (8.4% vs 16%; difference -7.6%; 95% CI -14.3% to -0.9%) were less frequent in the eTURB arm than in the cTURB arm. Operation time did not differ between the two techniques (26 min, interquartile range [IQR] 20-38 for eTURB vs 25 min, IQR 17-35 for cTURB; difference 1 min, 95% CI -25.9 to 4.99). Second-look TURB was performed in 24 patients in the eTURB arm and 34 in the cTURB arm, with no difference in the rate of residual papillary disease (pTa/pT1: 56% vs 55.9%; difference 0.1%, 95% CI -25.5% to 25.7%). At median follow-up of 13 mo (IQR 7-20), 18.4% of the patients in the eTURB arm and 16.7% in the cTURB arm had experienced bladder cancer recurrence (Cox hazard ratio 0.87, 95% CI 0.49-1.52; p = 0.6).

CONCLUSIONS

In patients with clinical NMIBC with up to three tumors of 1-3 cm in size, tumor removal via eTURB resulted in a higher rate of DM in the pathologic specimen in comparison to cTURB. Moreover, eTURB was associated with lower frequency of obturator reflex and bladder perforation than cTURB was. While improving on the quality indicators for NMIBC, the long-term differential oncologic benefits of eTURB remain uncertain.

PATIENT SUMMARY

We compared two techniques for removal of bladder tumors and found that tumor removal in a single piece, called en bloc resection, provides a better-quality specimen for pathology analysis and fewer complications in comparison to the conventional method. This trial is registered at ClinicalTrials.gov as NCT03718754.

A 10-year renaissance of en bloc resection of bladder tumors (ERBT): Are we approaching the peak or is it back to the trough?

BACKGROUND

The number of studies suggesting that en bloc resection of bladder tumor (ERBT) is superior to transurethral resection of bladder tumor (TURBT) for non-muscle-invasive bladder cancer (NMIBC) management is growing. The aim of this review is to discuss the features of these procedures and to determine the prospects of en bloc in NMIBC management.

MATERIALS AND METHODS

We conducted a literature search using two databases (Medline and Scopus) and included any research which reported ERBT outcomes.

RESULTS

The lasers with minimal tissue penetration depth are becoming the main tool for ERBT. Unfortunately, most of the systematic reviews continue to be characterized by high heterogeneity. However, recent studies indicate that ERBT may have the edge when it comes to the detrusor muscle rate and the quality of the histological specimen. ERBT may favor in terms of in-field relapse, but its rate in the studies varies greatly. As for out-field relapse-free survival, the data are still lacking. The strongest evidence supports that ERBT is superior to TURBT in complications rate (bladder perforation). ERBT is feasible irrespective to tumor size and location.

CONCLUSIONS

ERBT has gained in momentum with the increasingly widespread use of this kind of laser surgery. The introduction of novel sources (TFL and Thulium:YAG pulsed laser) will definitely affect how the field develops and will result in further improvements in safety and precision. The latest trials make us more certain in our belief that ERBT will be beneficial in terms of histological specimen quality, relapse rate and complications rate.

High-power green-light laser endoscopic submucosal dissection for non-muscle-invasive bladder cancer: A technical improvement and its initial application

Background

The technique of laser en bloc resection of bladder tumor (ERBT) has been a valuable alternative technique to transurethral resection of bladder tumor (TURBT). However, the combination of laser ERBT and endoscopic submucosal dissection (ESD) technique has not been well studied. Here, a novel technique integrating a high-power green-light laser with ESD was presented. This study aimed to evaluate the safety and efficacy of high-power green-light laser endoscopic submucosal dissection (HPL-ESD) for the treatment of primary non-muscle-invasive bladder cancer (NMIBC).

Materials and Methods

From January 2015 to December 2018, a total of 56 patients with NMIBC underwent HPL-ESD. All tumors were transurethral en bloc resected in the ESD technique. Perioperative clinical data were retrospectively collected and analyzed.

Results

All operations were safely performed by the technique of HPL-ESD without blood transfusion. The mean tumor diameter was 2.04 ± 0.65 cm, ranging from 0.5 to 3.5 cm. The mean operative time was 28.39 ± 16.04 min. The average serum hemoglobin decrease was 0.88 ± 0.54 g/dL. The mean postoperative catheterization time was 2.88 ± 0.94 days. The pathologic stages included pTa (32 cases), and pT1 (24 cases). Double-J stent indwelling was not performed for four patients whose tumors were adjacent to the ureteral orifice and no postoperative hydronephrosis was observed. Only one case of ectopic bladder tumor recurred due to irregular bladder irrigation during the 36-month follow-up.

Conclusion

HPL-ESD is a safe and effective alternative for the treatment of primary NMIBCs, especially for tumors adjacent to the ureteral orifice.

Current Techniques for En Bloc Transurethral Resection of Bladder Tumor: A Hands-on Guide Through the Energy Landscape

En bloc resection of bladder tumor (ERBT) has attracted interest as a potentially superior technique to transurethral resection of bladder tumor (TURBT) to obtain detrusor muscle in the specimen. Different ERBT techniques have been described, with bipolar electrocautery and laser being the more favored energy modalities. Electrocautery EBRT has an advantage in terms of widespread availability in clinics and ease of conversion to piecemeal resection in case of large bladder tumors in different locations. Laser EBRT has an advantage in preventing obturator nerve reflex, which is particularly useful for lateral wall tumors. Further research is needed to assess the potential case-related advantages of the ERBT techniques over each other. PATIENT SUMMARY: Surgical removal of a bladder tumor as a whole single piece, called en bloc resection, is a safe procedure for the diagnosis and treatment of noninvasive bladder cancer. In this mini-review we summarize the evidence for current techniques for en bloc resection.

En Bloc Resection Versus Conventional TURBT for T1HG Bladder Cancer: A Propensity Score-Matched Analysis

BACKGROUND

We aimed to assess the clinical, oncological, and pathological impact of en bloc resection of bladder tumors (ERBT) compared with conventional transurethral resection of bladder tumors (cTURBT) for pT1 high-grade (HG) bladder cancer.

PATIENTS AND METHODS

We retrospectively analyzed the record of 326 patients (cTURBT: n = 216, ERBT: n = 110) diagnosed with pT1 HG bladder cancer at multiple institutions. The cohorts were matched by one-to-one propensity scores based on patient and tumor demographics. Recurrence-free survival (RFS), progression-free survival (PFS), cancer-specific survival (CSS), and perioperative and pathologic outcomes were compared. The prognosticators of RFS and PFS were analyzed using the Cox proportional hazard model.

RESULTS

After matching, 202 patients (cTURBT: n = 101, ERBT: n = 101) were retained. There were no differences in perioperative outcomes between the two procedures. The 3-year RFS, PFS, and CSS were not different between the two procedures (p = 0.7, 1, and 0.7, respectively). Among patients who underwent repeat transurethral resection (reTUR), the rate of any residue on reTUR was significantly lower in the ERBT group (cTURBT: 36% versus ERBT: 15%, p = 0.029). Adequate sampling of muscularis propria (83% versus 93%, p = 0.029) and diagnostic rates of pT1a/b substaging (90% versus 100%, p < 0.001) were significantly better in ERBT specimen compared with cTURBT specimen. On multivariable analyses, pT1a/b substaging was a prognosticator of disease progression.

CONCLUSIONS

In patients with pT1HG bladder cancer, ERBT had similar perioperative and mid-term oncologic outcomes compared with cTURBT. However, ERBT improves the quality of resection and specimen, yielding less residue on reTUR and yielding superior histopathologic information such as substaging.

Development of a New Two-Arm Transurethral Surgical System for En Bloc Resection of Bladder Tumor: A Preclinical Study

Backgrounds and Objectives: To overcome the piecemeal nature of bladder tumor resection, en bloc resection of bladder tumor (ERBT) has been introduced. ERBT is difficult for surgeons to perform using the currently available system because it has only one arm. Herein, we aimed to develop a new transurethral surgical system to facilitate two-arm ERBT and to report the results of preclinical experiments using tumor phantoms. Methods: Initially, we aimed to develop a brand-new surgical system for ERBT but, after trial and error, we redirected our development to the creation of three elements: the left arm to grasp the tumor; the right arm to cut the tumor; and the system to operate the arms that can be attached to the existing surgical system (UES-40 SurgMaster^® [Olympus Co. Ltd., Tokyo, Japan]). The current system was evaluated by performing simulated ERBTs using tumor phantoms made from konjac jelly. Results: Following the assembly of developed arms into the UES-40 SurgMaster, we conducted preliminary ERBTs. After performing several resections, we adopted a basket-shaped forceps as the left arm instead of grasping forceps and an arched electrode as the right arm. The two arms and single endoscope were placed in an equilateral triangle. We performed ERBT for the tumor phantoms that ranged from 0.5 to 2.0 cm without major redo. Conclusion: Herein, we introduced our development for two-arm ERBT. The current concept of "two-hand transurethral surgery" has the potential to be developed in future in vivo and clinical trials.

Precise diagnosis and treatment of non-muscle invasive bladder cancer - A clinical perspective

According to the guidelines, transurethral resection of bladder tumor (TURBT) followed by intravesical therapy remains the standard strategy for the management of non-muscle invasive bladder cancer (NMIBC). However, even if patients receive standard strategy, the risk of postoperative recurrence and progression is high. From the clinical perspective, the standard strategy needs to be optimized and improved. Compared to conventional TURBT, the technique of en bloc resection of bladder tumor (ERBT) removes the tumor tissue in one piece, thus following the principles of cancer surgery. Meanwhile, the integrity and spatial orientation of tumor tissue is protected during the operation, which is helpful for pathologists to make accurate histopathological analysis. Then, urologists can make a postoperative individualized treatment plan based on the patient's clinical characteristics and histopathological results. To date, there is no strong evidence that NMIBC patients treated with ERBT achieve better oncological prognosis, which indicates that ERBT alone does not yet improve patient outcomes. With the development of enhanced imaging technology and proteogenomics technology, en bloc resection combined with these technologies will make it possible to achieve precise diagnosis and treatment of bladder cancer. In this review, the authors analyze the current existing shortcomings of en bloc resection and points out its future direction, in order to promote continuous optimization of the management strategy of bladder cancer.

Efficacy and safety of a novel 450 nm blue diode laser versus plasmakinetic electrocautery for the transurethral resection of non-muscle invasive bladder cancer: The protocol and result of a multicenter randomized controlled trial

Objectives

To be the first to apply a novel 450 nm blue diode laser in transurethral resection of bladder tumor (TURBt) to treat patients with non-muscle invasive bladder cancer (NMIBC) and evaluate its efficacy and safety during the preoperative period compared to the conventional plasmakinetic electrocautery.

Materials and Methods

Randomized controlled trial (RCT) in five medical centers was designed as a non-inferiority study and conducted from October 2018 to December 2019. Patients with NMIBC were randomized to the blue laser or plasmakinetic electrocautery group for TURBt. As the first study to evaluate this novel blue laser device, the primary outcome was the effective resection rate of bladder tumors, including effective dissection and hemostasis. The secondary outcomes were the perioperative records, including surgical time, postoperative indwelling catheter time, hospital stay length, blood loss, reoperation rate, wound healing and adverse events.

Results

A total of 174 patients were randomized to either the blue laser group (85 patients) or plasmakinetic electrocautery group (89 patients). There was no statistical significance in the clinical features of bladder tumors, including tumor site, number and maximum lesion size. Both the blue laser and plasmakinetic electrocautery could effectively dissect all visible bladder tumors. The surgical time for patients in the blue laser group was longer (p=0.001), but their blood loss was less than that of patients in the control group (p=0.003). There were no differences in the postoperative indwelling catheter time, hospital stay length, reoperation rate or other adverse events. However, the patients undergoing TURBt with the blue laser showed a faster wound healing at 3 months after operation.

Conclusion

The novel blue laser could be effectively and safely used for TURBt in patients with NMIBC, and this method was not inferior to plasmakinetic electrocautery during the perioperative period. However, TURBt with the blue laser may provide the benefit to reduce preoperative blood loss and accelerate postoperative wound healing. Moreover, longer follow-up to confirm recurrence-free survival benefit was required.

Systematic review and meta-analysis of randomized controlled trials of perioperative outcomes and prognosis of transurethral en-bloc resection vs. conventional transurethral resection for non-muscle-invasive bladder cancer

OBJECTIVES

This article aimed to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) of perioperative outcomes and prognosis of transurethral en-bloc resection versus conventional transurethral resection for non-muscle-invasive bladder cancer (NMIBC).

METHODS

We searched MEDLINE, Web of Science, and the Cochrane Controlled Register of Trials (CENTRAL) to find eligible RCTs. The studies were classified by version 2 of the Cochrane risk-of-bias tool for randomized trials. Review Manager 5.4.0 was used to evaluate the data. The certainty of the evidence was assessed using the Guideline Development Tool by GRADEpro GDT.

RESULTS

Seven RCTs with 1142 patients was included in the present study. The results indicated that bladder perforation (OR = 0.17; 95% CI 0.05 to 0.67; P = 0.01), obturator nerve reflex (OR = 0.03; 95% CI 0.01 to 0.13; P < 0.00001), residual tumor (OR = 0.24; 95% CI 0.08 to 0.77; P = 0.02) and repeat transurethral resection of bladder tumor (re-TURBT) (OR = 0.54; 95% CI 0.34 to 0.85; P = 0.008) were significantly reduced in the en-bloc resection group than the conventional resection group. However, there were no significant differences in hemoglobin deficit (p = 0.31), urethral stricture (p = 0.47), and detrusor muscle presence (P = 0.16) between both groups. Besides, resection time (p = 0.25), operative time (p = 0.20), catheter dwell time (p = 0.24), and length of hospital stay (p = 0.16) were similar in the two groups. Meanwhile, en-bloc resection yielded no advantage for the 3-month (P = 0.11), 6-month (P = 0.05), 1-year (P = 0.61), 2-year (P = 0.53), and 3-year (P = 0.26) tumor recurrence rates.

CONCLUSIONS

Our meta-analysis shows that transurethral en-bloc resection is associated with comparable outcomes to conventional transurethral resection for recurrence-free survival in NMIBC patients. En-bloc resection is more feasible and safer than conventional resection for NMIBC, with fewer intraoperative complications, less residual tumor, and less re-TURBT.

En bloc resection of bladder tumors: challenges and unmet needs in 2021

Non-muscle invasive bladder cancer accounts for the majority of new bladder cancer diagnoses, and endoscopic transurethral resection of bladder tumor (TURBT) represents the standard-of-care. Although a relatively safe and common procedure, TURBT is often hampered by the questionable quality of resection. The evolution of surgical techniques has brought en bloc resection of bladder tumor (ERBT) to the forefront. ERBT has emerged as an alternative to conventional TURBT, incorporating a more delicate en bloc sculpting and tumor excision, in contrast to 'piecemeal' resection by conventional TURBT. ERBT appears safe, feasible and effective with demonstrably higher rates of detrusor muscle in the pathologic specimen, all while providing better staging and obviating the need for a re-TURBT in selected patients. However, the method's adoption in the field is still limited. This review summarizes the recent evidence relevant to ERBT while further highlighting the technique's limitations and unmet needs.

En bloc resection for nonmuscle-invasive bladder cancer: selecting a proper laser

PURPOSE OF REVIEW

To discuss the most recent surgical lasers that have been made available to us and to evaluate their potential in performing en bloc resection of nonmuscle invasive bladder cancer.

RECENT FINDINGS

Laser en bloc resection of bladder tumors (ERBT) can be performed with a number of laser systems including Ho:YAG, GreenLight, diode, Tm:YAG and thulium fiber lasers (TFL). The data that is currently available suggests that the water-targeting devices (utilizing water as a primary chromophore - Ho:YAG, Tm:YAG, TFL) may have a number of advantages over hemoglobin-targeting systems (potassium titanyl phosphate:YAG, lithium triborate:YAG). One recent addition to the surgical armamentarium Moses effect enhanced Ho:YAG and the TFL (being able to work both in quasi-continuous and SuperPulsed modes) necessitates careful discussion and comparison with the other available devices.

SUMMARY

The majority of available lasers have proven to be safe to use and compared to electrocautery allow for lower rates of obturator nerve reflex and result in fewer bleeding complications. The minimal penetration depth and decreased peak power of Tm:YAG and TFLs render them the devices of choice when it comes to ERBT. Unfortunately, more studies on ERBT with TFL are needed in order for us to make a sound assessment of the respective pros and cons.

Comparison of Clinicopathologic and Oncological Outcomes Between Transurethral En Bloc Resection and Conventional Transurethral Resection of Bladder Tumor: A Systematic Review, Meta-Analysis and Network Meta-Analysis with Focus on Different Energy Sources

Introduction: It has been hypothesized that transurethral en bloc (TUEB) of bladder tumor offers benefits over conventional transurethral resection of bladder tumor (cTURBT). This study aimed to compare disease outcomes of TUEB and cTURBT with focus on the different energy sources. Methods: A systematic search was performed using PubMed and Web of Science databases in June 2021. Studies that compared the pathological (detrusor muscle presence), oncological (recurrence rates) efficacy, and safety (serious adverse events [SAEs]) of TUEB and cTURBT were included. Random- and fixed-effects meta-analytic models and Bayesian approach in the network meta-analysis was used. Results: Seven randomized clinical trials (RCTs) and seven non-RCTs (NRCT), with a total of 2092 patients. The pooled 3- and 12-month recurrence risk ratios (RR) of five and four NRCTs were 0.46 (95% CI 0.29-0.73) and 0.56 (95% CI 0.33-0.96), respectively. The pooled 3- and 12-month recurrence RRs of four and seven RCTs were 0.57 (95% CI 0.25-1.27) and 0.89 (95% CI 0.69-1.15), respectively. The pooled RR for SAEs such as prolonged hematuria and bladder perforation of seven RCTs was 0.16 (95% CI 0.06-0.41) in benefit of TUEB. Seven RCTs (n = 1077) met our eligibility criteria for network meta-analysis. There was no difference in 12-month recurrence rates between hybridknife, laser, and bipolar TUEB compared with cTURBT. Contrary, laser TUEB was significantly associated with lower SAEs compared with cTURBT. Surface under the cumulative ranking curve ranking analyses showed with high certainty that laser TUEB was the best treatment option to access all endpoints. Conclusion: While NRCTs suggested a recurrence-free benefit to TUEB compared with cTURBT, RCTs failed to confirm this. Conversely, SAEs were consistently and clinically significantly better for TUEB. Network meta-analyses suggested laser TUEB has the best performance compared with other energy sources. These early findings need to be confirmed and expanded upon.