Thulium:yttrium-aluminum–garnet Laser for En Bloc Resection of Bladder Cancer: Clinical and Histopathologic Advantages

How do endoscopic bladder tumor resection techniques affect pathology practice? EAU Section of Uro-Technology (ESUT) and Uropathology (ESUP) survey

PURPOSE

We aimed to examine how different endoscopic bladder tumor resection techniques affect pathologists' clinical practice patterns.

METHODS

An online survey including 28 questions clustered in four main sections was prepared by the ESUT ERBT Working Group and released to the pathologists working in the institutions of experts of the ESUT Board and the working groups and experts in the uropathology working group. A descriptive analysis was performed using the collected data.

RESULTS

Sixty-eight pathologists from 23 countries responded to the survey. 37.3% of the participants stated that they always report the T1 sub-staging. Of those who gave sub-staging, 61.3% used T1a, b. 85.2% think that en bloc samples provide spatial orientation faster than piecemeal samples, and 60% think en bloc samples are timesaving during an inspection. 55.7% stated that whether the tissue sample is en bloc or piecemeal is essential. 57.4% think en bloc sample reduces turnaround time and is cost-effective for 44.1%. A large number of pathologists find that the pathology examination of piecemeal samples has a longer learning curve.

CONCLUSION

The survey shows that pathologists think that they can diagnose faster, accurately, and cost-effectively with ERBT samples, but they do not often encounter them in practice. Moreover, en bloc samples may be a better choice in pathology resident training. Evidence from real-life observational pathology practice and clinical research can reveal the current situation more clearly and increase awareness on proper treatment in endoscopic management of bladder tumors.

Use of lasers in gastrointestinal endoscopy: a review of the literature

Lasers emit highly directional light with consistent wavelengths, and recent studies have demonstrated their successful applications in gastrointestinal endoscopic therapy. Although argon plasma coagulators (APC) became the preferred treatment option due to improved safety profile and lower costs, advancements in laser and optic fiber manufacturing have reignited interest in laser treatment. Different laser wavelengths have distinct features and applications based on their tissue absorption coefficient. Lasers with shorter wavelengths are effectively absorbed by hemoglobin, resulting in a good coagulation effect. Near-infrared lasers have ability to ablate solid tumors, while far-infrared lasers can make precise mucosal incisions without causing peripheral thermal damage. Lasers have proven to be highly applicable to endoscopy devices such as endoscopes, endoscopic ultrasound (EUS), double-balloon enteroscopes (DBE), and endoscopic retrograde cholangiopancreatography (ERCP), making them a potent tool to enhance the effectiveness of endoscopic treatments with minimal adverse events. This review aims to help readers understand the applications and effectiveness of lasers in gastrointestinal endoscopy, with the potential to promote the development and application of laser technology in the medical field.

Efficacy and safety of 2-micron laser versus conventional trans-urethral resection of bladder tumor for non-muscle-invasive bladder tumor: A systematic review and meta-analysis

Aim

To compare the clinical efficacy and safety of 2-micron laser and conventional trans-urethral resection of bladder tumor (TURBT) in the treatment of non-muscle-invasive bladder tumor (NMIBT), providing evidence-based evidence for clinical treatment.

Materials and Methods

PubMed, Embase, Cochrane Library, CMB, CNKI, and WanFang databases were searched since their inception until December 2021 for all eligible randomized controlled trials (RCTs) related to 2-micron laser and TURBT for treating NMIBT. Two researchers independently screened the literature, extracted outcome indicators, and assessed the risk of bias according to the inclusion and exclusion criteria. Binary and continuous variables were calculated by relative risk (RR) and mean difference (MD) with 95% confidence interval (95%CI), respectively. RevMan 5.4 and Stata 15.0 software were used for all statistical analysis.

Results

A total of ten RCTs involving 1,163 patients were included: 596 cases in the 2-micron laser group and 567 cases in the TURBT group. The results of the meta-analysis revealed that 2-micron laser has advantages over the TURBT in operative duration (MD = -2.94, 95% confidence interval (CI) [-8.55, 2.68], P = 0.31), operative blood loss (MD = -19.93, 95%CI [-33.26, -6.60], P = 0.003), length of hospital stay (MD = -0.94, 95%CI [-1.38, -0.50], P < 0.001), post-operative bladder irrigation time (MD = -28.60, 95%CI [-50.60, -6.59], P = 0.01), period of catheterization days (MD = -1.07, 95%CI [-1.73, -0.40], P = 0.002), obturator nerve reflex (RR = -0.06, 95%CI [0.02, 0.15], P < 0.001), bladder perforation (RR = 0.14, 95%CI [0.06, 0.35], P < 0.001), and bladder irritation (RR = 0.30, 95%CI [0.20, 0.46], P < 0.001). There was no significant difference between the two surgical methods in post-operative urethral stricture and short-term recurrence of NMIBT.

Conclusion

Compared with TURBT, 2-micron laser may be safer and more effective for NMIBT management. However, these conclusions need to be validated through more high-quality RCTs because of the quality limitations and publication bias of the included studies.

Can a reresection be avoided after initial en bloc resection for high-risk nonmuscle invasive bladder cancer? A systematic review and meta-analysis

Background

This study aims to evaluate the effectiveness of en bloc resection for patients with nonmuscle invasive bladder cancer (NMIBC) and explore whether a reresection can be avoided after initial en bloc resection.

Material and methods

We conducted research in PubMed, EMBASE, Cochrane Library, and Web of Science up to October 12, 2021, to identify studies on the second resection after initial en bloc resection of bladder tumor (ERBT). R software and the double arcsine method were used for data conversion and combined calculation of the incidence rate.

Results

A total of 8 studies involving 414 participants were included. The rate of detrusor muscle in the ERBT specimens was 100% (95%CI: 100%–100%), the rate of tumor residual in reresection specimens was 3.2% (95%CI: 1.4%–5.5%), and the rate of tumor upstaging was 0.3% (95%CI: 0%–1.5%). Two articles compared the prognostic data of the reresection and non-reresection groups after the initial ERBT. We found no significant difference in the 1-year recurrence-free survival (RFS) rate (OR = 1.44, 95%CI: 0.67–3.09, P = 0.35) between the two groups nor in the rate of tumor recurrence (OR = 0.72, 95%CI: 0.44–1.18, P = 0.2) or progression (OR = 0.98, 95%CI: 0.33–2.89, P = 0.97) at the final follow-up.

Conclusions

ERBT can almost completely remove the detrusor muscle of the tumor bed with a very low postoperative tumor residue and upstaging rate. For high-risk NMIBC patients, an attempt to appropriately reduce the use of reresection after ERBT seems to be possible.

A Systematic Review on the Role of Repeat Transurethral Resection after Initial en Bloc Resection for Non-Muscle Invasive Bladder Cancer

International guidelines recommend repeat transurethral resection of bladder tumors (reTURB) for selected patients with high-risk non-muscle invasive bladder cancer to remove possible residual tumors, restage tumors and improve the therapeutic outcome. However, most evidence supporting the benefits of reTURB is from conventional TURB. The role of reTURB in patients receiving initial En bloc resection of bladder tumor (ERBT) is still unknown. PubMed, Embase, Web of Science, The Cochrane Library, and China National Knowledge Infrastructure (CNKI) were systematically searched. Finally, this systematic review and meta-analysis included twelve articles, including 539 patients. The rates of residual tumor and tumor upstaging detected by reTURB after ERBT were 5.9% (95%CI, 2.0%–11.1%) and 0.0% (95%CI, 0.0%–0.5%), respectively. Recurrence-free survival, tumor recurrence and progression were comparable between patients with and without reTURB after initial ERBT. The pooled hazard ratios of 1-year, 2-year, 3-year and 5-year recurrence-free survival were 0.74 (95%CI, 0.36–1.51; p = 0.40), 0.76 (95%CI, 0.45–1.26; p = 0.28), 0.83 (95%CI, 0.53–1.32; p = 0.43) and 0.83 (95%CI, 0.56–1.23; p = 0.36), respectively. The pooled relative risks of recurrence and progression were 0.87 (95%CI, 0.64–1.20; p = 0.40) and 1.11 (95%CI, 0.54–2.32; p = 0.77), respectively. Current evidence demonstrates that reTURB after ERBT for bladder cancer can detect relatively low rates of residual tumor and tumor upstaging and appears not to improve either recurrence or progression.

1470 nm/980 nm dual-wavelength laser is safe and efficient for the en-bloc resection of non-muscle invasive bladder cancer: A propensity score-matched analysis

OBJECTIVE

To evaluate the efficacy and safety of a 1470 nm/980 nm dual-wavelength laser system used for the en-bloc resection of non-muscle invasive bladder cancer (NMIBC) compared with transurethral resection of bladder tumour (TURBT).

METHODS

This retrospective study analysed the demographic and clinical data from patients diagnosed with NMIBC that were treated by either dual laser or TURBT. Intraoperative characteristics, postoperative characteristics and outcomes between the two groups were compared.

RESULTS

This study analysed 64 patients, 32 in each group. No severe complications were identified in either group. After propensity score-matching, there were no significant differences between the two groups in terms of the demographics, clinical and tumour characteristics. There was no significant difference between the two groups in terms of specimen quality. In the laser group, intraoperative blood loss was significantly lower and significantly fewer patients required continuous bladder irrigation after surgery, compared with the TURBT group. No significant differences were observed in the catheterization time, gross haematuria time and hospitalization time. Operation time in the laser group was significantly longer compared with the TURBT group. No significant difference was found in the recurrence and progression rates between the two groups.

CONCLUSIONS

The 1470 nm/980 nm dual-wavelength laser provides a safe and effective surgical treatment option for patients with NMIBC.

En bloc transurethral resection of bladder tumor: A review of the literature

Bladder cancer remains one of the most common malignancies of the genitourinary tract. Transurethral resection of the bladder tumor (TURBT) via cystoscopy with examination under anesthesia remains the primary method for determining the diagnosis and clinical stage of bladder cancer. Given the substantial cost of treatment and risk of bladder cancer recurrence after TURBT, novel approaches to transurethral resection, such as the en bloc technique, have been developed in an attempt to address these limitations. In this review, we examined the postoperative and oncological outcomes of en bloc TURBT compared to traditional resection techniques. Further prospective clinical studies, however, are still necessary to determine whether these alternative technologies or surgical techniques may improve treatment in bladder cancer patients.

Level of evidence: Not applicable.

Outcomes of stratified transurethral resection of bladder tumor: A propensity score-matched analysis

BACKGROUND/PURPOSE

Several strategies have been reported for improving the integrity of transurethral resection of bladder tumor (TURBT). However, no standard has been established. Stratified TURBT (SR) is one of protocols for TURBT, wherein exophytic tumors are first resected and retrieved, and tumor bases are then resected. In this study, we aimed to evaluate the outcomes of SR in patients with nonmuscle invasive bladder cancer (NMIBC).

METHODS

From January 2012 to December 2017, patients newly diagnosed as having NMIBC with a follow-up period of more than 2 years were enrolled and categorized into SR and conventional TURBT (CR) groups. Propensity score matching at a 2:1 ratio was performed. Outcomes were the detrusor muscle sampling rate, recurrence-free survival (RFS), and progression-free survival (PFS).

RESULTS

In total, 205 patients were included in our study. The detrusor muscle sampling rate was higher in the SR group (P = 0.043). After propensity score matching, 162 patients were selected for outcome analysis, with 108 and 54 patients undergoing SR and CR, respectively. Compared with the CR group, the SR group showed a lower recurrence rate (P = 0.015) and better RFS in univariate (P = 0.010) and multivariate (P = 0.006) Cox proportional hazards regression. Progression rate and PFS were not significantly different between the two groups.

CONCLUSION

SR results in a higher detrusor muscle sampling rate and better disease outcomes. Our findings suggest that SR is a promising strategy for TURBT in patients with NMIBC.

Transurethral resection of bladder tumour (TURBT)

The goals of transurethral resection of bladder tumour (TURBT) are to identify and eradicate visualized bladder tumour if technically safe and feasible and to obtain a specimen of satisfactory quality to enable accurate histological diagnosis. In the setting of high grade bladder tumour this generally entails the inclusion of detrusor muscle and assessment for the presence of associated carcinoma in situ (CIS), lymphovascular involvement or any variant form of bladder cancer. This will assist in determining risk stratification and prognostication of the bladder cancer and guides further treatment planning. Conversely, if suboptimal TURBT is performed there will be detrimental consequences on patient outcomes in regards to undergrading or understaging, increased recurrence or progression, and subsequently need for further treatments including more invasive interventions. This review article firstly summarises the key principles and complications of TURBT, as well as significance of re-TURBT. We also discuss a number of modifications and advances in detection technology and resection techniques that have shown to improve perioperative as well as pathological and oncological outcomes of bladder cancer. They include enhanced cystoscopy such as blue light cystoscopy (BLC), narrow band imaging (NBI) and en bloc resection of bladder tumour (ERBT) technique using various types of energy source.

Can a second resection be avoided after initial thulium laser endoscopic en bloc resection for non-muscle invasive bladder cancer? A retrospective single-center study of 251 patients

Background

This study aimed to evaluate the efficacy of transurethral thulium laser en bloc resection of the bladder tumor (TmLRBT) in patients with non-muscle invasive bladder cancer (NMIBC) and to investigate whether a second resection can be avoided.

Methods

From June 2012 to June 2018, 251 newly diagnosed patients with NMIBC were enrolled in this retrospective study; all patients received regular administration of pirarubicin after the initial resection. A second transurethral resection (TUR) was performed in patients within 2–6 weeks after the initial TmLRBT in group 1. Patients in group 2 only underwent cystoscopy at 3 months.

Results

Second surgery results indicate that recurrence was detected histopathologically in 6/108 and 11/143 patients in group 1 and 2, respectively (P = 0.52); Progression was observed in 2 patients in each group (P = 0.34). The mean follow-up duration was 40.1 months, with no significant difference between the groups (P = 0.32). Recurrence was observed in 23 (21.3%) and 39 (27.3%) patients in groups 1 and 2 during the follow-up, respectively (P = 0.34); disease progression occurred in 4 (3.8%) patients in group 1 compared with 7 (4.0%) in group 2 (P = 0.20).

Conclusion

Complete removal of tumors can be achieved by TmLRBT. This technique may decrease the number of second TURs.

En-bloc resection of bladder tumors for pathological staging: the value of lateral margins analysis

BACKGROUND

In endoscopic resection of colorectal tumors, the pathological assessment of the lateral margins is a strong predictor of tumor recurrence after resection. The aim of the current study is to evaluate the value of the peritumoral margins assessment in ERBT on tumor recurrence.

METHODS

We retrospectively analyzed the data of 50 consecutive patients with NMIBC and treated by ERBT between January and December 2017.

RESULTS

The lateral margins showed dysplasia in 16 patients and malignancy in three patients. Local recurrence occurred in 14 (28%) patients. It was noted that 57% of patients with recurrence showed some degree of dysplasia or malignancy in the lateral margin; however, on multivariate logistic regression lateral margins lesions were not significantly associated with recurrence (OR 2.175, 95% CI: 0.430-10.996, P=0.35).

CONCLUSIONS

ERBT may improve the pathological report of bladder tumor. There was a trend toward increased rate of recurrence in patients with dysplasia or malignancy in their lateral margins; however, this was not statistically significant on multivariate analysis. Further studies with larger sample sizes are required to assess the value of lateral margin analysis.

Is the En Bloc Transurethral Resection More Effective than Conventional Transurethral Resection for Non-Muscle-Invasive Bladder Cancer? A Systematic Review and Meta-Analysis

BACKGROUND

En bloc transurethral resection (ERBT) is a major topic of discussion as an alternative to conventional transurethral resection (cTURBT) for the treatment of non-muscle-invasive bladder cancer (NMIBC) addressing the limitations of cTURBT.

METHODS

We searched through electronic databases including Embase, Cochrane Library, MEDLINE, Web of Science, PubMed, and Google Scholar for articles published up to April 1, 2019; RevMan 5.3 was used to conduct this meta-analysis. Results were expressed as 95% confidence intervals (CI) and risk differences (RD).

RESULTS

Nine trials met the inclusion criteria (n = 1,020 patients): 1 study was a randomized controlled trial including a total of 142 participants, 4 studies had a prospective paired design including 605 patients, and 4 studies were retrospective (n = 273 patients). Duration of continuous postoperative bladder irrigation (RD -0.16; 95% CI -3.47 to 0.28; I2 = 97%; p = 0.10) and operation time (RD 0.05; 95% CI -0.23 to 0.32; I2 = 79%; p = 0.74) were not significantly different between ERBT and cTURBT. However, hospitalization time (I2 = 96%; χ2 = 203.16; p = 0.01) and catheterization time (I2 = 95%; χ2 = 163.24; p = 0.02), as well as 24-month recurrence rate (I2 = 0%; χ2 = 0.98; p = 0.008) were significantly better using the ERBT scheme. The incidence of urethral stricture between both schemes (95% CI -0.03 to 0.02; p = 0.50) was not different, but complications such as obturator nerve reflex (95% CI 0.01 to 0.12; p < 0.00001) and bladder perforation (95% CI 0.05 to 0.59; p = 0.50) were less frequent in the ERBT group.

CONCLUSION

ERBT is an effective treatment approach with some advantages for NMIBC. Our meta-analysis revealed that hospitalization time, catheterization time, and 24-month recurrence rate is superior in patients treated with ERBT than cTURBT, and ERBT patients also have a lower complication rate. Furthermore, ERBT improves the quality of tumor specimens and decreases the frequency of repeat transurethral bladder cancer resection. Further randomized controlled trials are needed to confirm our results.

Technical developments in transurethral resection of bladder tumours

Bladder cancer is one of the most common malignancies worldwide. The transurethral resection of bladder tumour (TURB) remains the gold standard in both diagnostics and treatment. Because of the importance of TURB in bladder cancer management and the fact that TURB is one of the most commonly performed urologic procedures, it is the subject of continuous technological development. The latest advances in the field of endourology are aimed at increasing surgical accuracy and thus reducing the risk of bladder tumour recurrence and progression. However, despite the constant progress in technology and technique, there are still a lack of good quality data showing the superiority of any of the methods. The aim of this paper is to present available data on new technological developments in surgical technique of TURB. Advantages and disadvantages of currently available methods are discussed, and literature showing their effectiveness and safety is shown.

A pilot study to assess the safety and usefulness of combined transurethral endoscopic mucosal resection and en-bloc resection for non-muscle invasive bladder cancer

Background

Transurethral resection (TUR) is the standard operation used for non-muscle invasive bladder cancer (NMIBC). Although most solid tumors are principally removed via single block resection without incising the mass, disruption of the lesion is unavoidable in traditional TUR. Furthermore, pathological diagnosis is often difficult due to heat-related denaturation of tissues in TUR. Although transurethral en-bloc resection is useful for judging tumor invasion, it is associated with a prolonged operative duration. We attempted to show the safety and usefulness of combined endoscopic mucosal resection (EMR) and en-bloc resection in NMIBC patients.

Methods

We investigated 39 patients with clinical NMIBC who were treated using our original EMR + en-bloc resection technique, which involved removal of the tumor mass that protruded from the mucosa, using a polypectomy snare similar to that used for EMR. The residual lesion was removed using en-bloc resection. The operative period, duration of hospitalization, and recurrence rates were compared with those of conventional TUR (n = 31).

Results

The mean (standard deviation, range) time interval for EMR and total operative duration were 1.6 (1.1, 1–5) min and 18.3 (10.5, 3–48) min, respectively. The total operative duration was comparable to that of TUR (17.3 min, p = 0.691). The mean duration of catheterization in the EMR + en-bloc resection group (4.2 days) was also similar to that in the TUR group (3.7 days; p = 0.285). No severe complications were observed with EMR + en-bloc resection. The pathologists were able to determine tumor invasiveness with considerable certainty in all specimens obtained via the EMR + en-bloc procedure than via TUR, and the difference in the ease of diagnosis was statistically significant (p = 0.016). Recurrence rates were comparable (p = 0.662) between the EMR + en-bloc (15.4%) and TUR groups (19.4%).

Conclusions

Our results demonstrated that the EMR + en-bloc resection technique is feasible, safe, and useful for treating patients with NMIBC. Furthermore, this technique helps provide a more accurate pathological diagnosis.

Three-dimensional histopathological reconstruction of bladder tumours

BACKGROUND

Histopathological analysis is the cornerstone in bladder cancer (BCa) diagnosis. These analysis suffer from a moderate observer agreement in the staging of bladder cancer. Three-dimensional reconstructions have the potential to support the pathologists in visualizing spatial arrangements of structures, which may improve the interpretation of specimen. The aim of this study is to present three-dimensional (3D) reconstructions of histology images.

METHODS

En-bloc specimens of transurethral bladder tumour resections were formalin fixed and paraffin embedded. Specimens were cut into sections of 4 μm and stained with Hematoxylin and Eosin (H&E). With a Phillips IntelliSite UltraFast scanner, glass slides were digitized at 20x magnification. The digital images were aligned by performing rigid and affine image alignment. The tumour and the muscularis propria (MP) were manually delineated to create 3D segmentations. In conjunction with a 3D display, the results were visualized with the Vesalius3D interactive visualization application for a 3D workstation.

RESULTS

En-bloc resection was performed in 21 BCa patients. Per case, 26-30 sections were included for the reconstruction into a 3D volume. Five cases were excluded due to export problems, size of the dataset or condition of the tissue block. Qualitative evaluation suggested an accurate registration for 13 out of 16 cases. The segmentations allowed full 3D visualization and evaluation of the spatial relationship of the BCa tumour and the MP.

CONCLUSION

Digital scanning of en-bloc resected specimens allows a full-fledged 3D reconstruction and analysis and has a potential role to support pathologists in the staging of BCa.

The rational and benefits of the second look transurethral resection of the bladder for T1 high grade bladder cancer

The second look transurethral resection of the bladder (TURB) represents a fundamental step in the treatment of papillary non-muscle invasive bladder cancer (NMIBC); it is therefore recommended by all guidelines. However, not all the literature agrees on its staging value and its ability to improve oncological outcomes of patients. Therefore, the purpose of this review is to evaluate the strengths and weaknesses of second look TURB, trying to depict its evolving role in the management of high grade NMIBC. Using Medline, a non-systematic review was performed including articles between January 2000 and June 2018. English language original articles, reviews and editorials were selected based on their clinical relevance. To date, TURB seems to be largely inadequate in retrieving a correct diagnosis and in removing all tumor tissue. Second look TURB maximizes staging accuracy, allows to clear residual cancer and yields prognostic advantages allowing key information to identify possible candidates for immediate radical cystectomy for very high risk T1HG tumors. Moreover, it seems to have a therapeutic benefit by improving recurrence- and progression-free survivals. However, few recent large studies showed that these advantages seem to be limited to patients without detrusor muscle present at first resection. Similarly, the presence of residual disease and the risk of upstaging are related to the presence of detrusor muscle in specimen. It could well be that in the future the presence of detrusor muscle would be a quality criteria to avoid an unnecessary second look TURB as shown by recent studies using the en-bloc resection technique. Finally, it has to be underlined that this is a surgical procedure not free of risks and complications and with a non-negligible impact on patients’ quality of life, waiting lists and healthcare costs. Therefore, future studies trying to identify the criteria that may better allow which patients to select for a second look TURB while avoiding an unnecessary intervention with possible risks and associated cost are needed to allow a personalized approach to even this one size fits all strategy.

A retrospective comparison of thulium laser en bloc resection of bladder tumor and plasmakinetic transurethral resection of bladder tumor in primary non-muscle invasive bladder cancer

Bladder cancer is currently considered the most common malignancy of the urinary tract. Thulium laser en bloc resection of bladder tumor (TmLRBT) and plasmakinetic transurethral resection of bladder tumor (PK-TURBT) are two alternative common procedures used in our department to manage patients with primary non-muscle invasive bladder cancer (NMIBC) over the past decade. In this work, the safety and efficacy of TmLRBT were retrospectively compared to those of PK-TURBT in patients with primary NMIBC. From January 2013 to December 2015, 256 patients diagnosed with primary NMIBC were selected for this retrospective study. A total of 136 consecutive patients diagnosed with primary NMIBC were enrolled in the TmLRBT group. A similar historical cohort of 120 consecutive patients who underwent PK-TURBT was used to compare the two procedures. Clinical data, including age, gender, tumor characteristics, operation duration, hospitalization, irrigation, catheterization, and intraoperative and postoperative complications, were recorded. There were no significant differences in age, gender, mean tumor size, mean tumor number, tumor location, or risk between the TmLRBT and PK-TURBT groups. The TmLRBT group was associated with a significantly shorter operation duration (25.96 ± 21.19 min vs 37.18 ± 25.77 min, P = 0.018) and a shorter hospitalization time (3.11 ± 1.05 days vs 5.24 ± 2.06 days, P = 0.036). The postoperative irrigation time (6.33 ± 4.05 h vs 14.76 ± 6.28 h, P = 0.027) and catheterization time (2.03 ± 1.61 days vs 4.27 ± 1.17 days, P = 0.035) in the TmLRBT group were lower than those in the PK-TURBT group. No significant differences in fever and rebleeding were found in the TmLRBT and PK-TURBT groups. There were no significant differences in the overall, low-risk, intermediate-risk, and high-risk recurrence-free rates between the two groups (P = 0.43, P = 0.68, P = 0.71, and P = 0.24, respectively). The proportion of bladder detrusor muscle (BDM) identified in pathologic specimens of the TmLRBT group was higher than that in the PK-TURBT group (P = 0.006). TmLRBT may reduce operation duration time, hospitalization time, postoperative irrigation time, and catheterization time. TmLRBT is considered safer and more effective in treating primary NMIBC. Recurrence-free rates did not differ between groups.

Resistance of different guidewires to laser injury: an in-vitro experiment

BACKGROUND

In urology, lasers are used in a variety of endoscopic procedures such as ureteroscopy and retrograde renal surgery for stone fragmentation of urinary calculi and ablation of urothelial tumors. To perform these procedures, guidewires are used as a preliminary safe-mainstay for referencing the urinary tract. This study aims to determine the effect of two different lasers: holmium:YAG (Ho:YAG) and thulium:YAG (Tm:YAG) lasers on metal guidewires with PTFE coating (PTFE), nitinol guidewires with hydrophilic coating (Hydrophilic) and nitinol guidewires with hydrophilic listed coating (Zebra).

METHODS

Different combinations of frequency (5, 10 and 12 Hz) and energy per pulse (0.5, 1.5, and 2.6 J) of Ho:YAG laser were applied on the three kinds of guidewires in two experiments (50 J vs. 100 J of total energy). For the Tm:YAG laser three power levels (5, 35, and 70 W) with a total energy of 100 J were applied to the guidewires. The degree of damage (0 to 5) of the guidewire was assessed after each laser application.

RESULTS

A higher degree of injury of guidewires was related to higher values of total energy used for the Ho:YAG laser (P=0.036), and to higher values of power applied with the Tm:YAG (P=0.051). The most resistant guidewire to Ho:YAG laser energy was Zebra, followed by PTFE and Hydrophilic (P<0.001). With the Tm:YAG laser, PTFE guidewire appears to be the most resistant and the Hydrophilic the most fragile, although without reaching the statistical significance (P=0.223).

CONCLUSIONS

Both lasers revealed a harmful effect on the three tested guidewires. There was an association between the degree of injury and the amount of Ho:YAG laser energy and Tm:YAG laser power. The guidewire Zebra proved to be the safest when using Ho:YAG laser and the PTFE guidewire the most resistant to laser Tm:YAG. Further studies are necessary to confirm these results.

Treatment of upper tract urothelial carcinoma with ureteroscopy and thulium laser: a retrospective single center study

BACKGROUND

Treatment with the combination of ureteroscopy and thulium laser ablation may provide an alternative to radical nephroureterectomy (RNU) for patients with upper tract urothelial carcinoma (UTUC). The purpose of this study was to investigate the efficacy and safety of this technique.

METHODS

We performed a retrospective review of the data for patients who were treated surgically for upper tract urothelial carcinoma in a single center. It included 32 patients treated by endoscopic thulium laser resection and 107 patients treated by radical nephroureterectomy (RNU). We compared the data of patient sex, age at diagnosis, location of carcinoma, length of hospitalization, tumor site, size, grade, recurrence, preoperative creatinine and postoperative creatinine in two groups. Patients were examined by ureteroscopy every 3 months during the first year after surgery, then every 6 months each year.

RESULTS

All 32 patients were treated successfully, among which 6 were operated by a flexible ureteroscope. The average tumor size was 13 ± 7 mm in diameter. The tumor was rated as low grade in 27 patients and high grade in 5 patients. Ureteral stricture developed in 4 patients 3 months later after surgery, but the stricture was succesfully treated through endoscopic dilation. Seven patients had tumor recurrence, 3 of which underwent nephroureterectomy during the follow-up. Postoperative creatinine levels (umol/L) were respectively 89 ± 7.5 in laser group and 123 ± 15.4 in RNU group (p < 0.01). Length of hospitalization was respectively 3.6 ± 1.9 and 8.6 ± 2.4 days (p < 0.01). Local or bladder recurrence rate of thulium laser group and RNU group was respectively 21.9 and 13.1% (p < 0.01).

CONCLUSIONS

Thulium laser group is associated with a less loss of renal function, a shorter length of hospitalization, but a higher rate of tumor recurrence. Thulium laser therapy combined with ureteroscopic treatment can be considered as an acceptable treatment for selected cases of UTUC. Lifetime intensive surveillance is necessary.

A novel transurethral resection technique for superficial bladder tumor: retrograde en bloc resection

BACKGROUND

Transurethral resection of bladder tumor (TURBT) is the standard approach to bladder tumors but suffers from several disadvantages. The aim of this study was to evaluate the safety and efficacy of a novel procedure of retrograde en bloc resection of bladder tumor (RERBT) with conventional monopolar resection electrode for the treatment of superficial bladder tumors.

METHODS

RERBT and conventional TURBT (C-TURBT) were conducted, respectively, in 40 and 50 patients diagnosed with superficial papillary bladder tumors. In the RERBT group, the tumors were en bloc removed retrogradely under direct vision using a conventional monopolar electrode. Patients' clinicopathological, intraoperative, and postoperative data were compared retrospectively between the RERBT and C-TURBT groups.

RESULTS

Of the 90 patients, 40 underwent RERBT and 50 underwent C-TURBT. Both groups were comparable in clinicopathological characteristic. RERBT could be performed as safely and effectively as C-TURBT. There were no significant differences in operative time and surgical complications. The cumulative recurrence rates between groups were similar during up to 18 months follow-up. The detrusor muscle could be identified pathologically in 100% of RERBT tumor specimens and the biopsy of tumor bases, but only in 54 and 70%, respectively, of C-TURBT samples (P < 0.01).

CONCLUSIONS

The RERBT technique is feasible and safe for superficial bladder tumors using conventional monopolar resection setting, with the advantages of adequate tumor resection and the ability to collect good quality tumor specimens for pathological diagnosis and staging compared to conventional TURBT.

Ex vivo experimental study on the Thulium laser system: new horizons for interventional endoscopy (with videos)

BACKGROUND AND STUDY AIMS

 The Thulium laser system (TLS) is an emerging interventional tool adopted in many surgical specialties. Its 2.0-μm wavelength allows precise coagulation (0.2 - 0.4 mm in depth) and cutting, limiting the possibilities of collateral injuries. We tested the impact of the TLS for gastric endoscopic submucosal dissection (ESD) and per oral endoscopic myotomy (POEM) ex vivo in pigs.

MATERIALS AND METHODS

  Ex vivo porcine stomach and esophagus models underwent 2 POEMs, and 3 ESDs (mean diameter 3.5 cm) with TLS using a 272-µm and a 365-µm thick optical fibers. Both continuous and pulsed laser emission were evaluated. Subsequent histopathological analysis was performed by an expert GI pathologist on the whole porcine models.

RESULTS

 Complete POEMs and gastric ESDs were successfully performed in all cases in 30 to 70 and 15 to 20 minutes. Both optical fibers were equally effective and precise. The best power output for mucosal incision was 25 to 30 W during ESD and 25 W for POEM using continuous laser emission. During submucosal dissection and tunneling the favorite power output was 20 W and 15 to 20 W, respectively, operating in continuous mode. No transmural perforation occurred throughout the operations and histopathology confirmed the absence of accidental muscular layer damage.

CONCLUSIONS

 The TLS stands out as a precise and manageable instrument in ex vivo models. This technique appears to be a promising tool for advanced interventional endoscopy.

En Bloc Transurethral Resection of Bladder Tumors: A New Standard?

OBJECTIVE

To assess safety and efficacy, namely pathological assessment of the specimen and recurrence rate, of en bloc transurethral resection (EBTUR) of bladder tumor.

MATERIALS AND METHODS

We performed a systematic review of the available literature on PubMed. Seventeen articles, mainly prospective case series, were found. EBTUR is performed with a great variety of equipments, whereas the resection technique is similar.

RESULTS

Overall, 895 patients have been submitted to EBTUR, accounting for 1191 lesions. Forty complications (4%) were computed. Only 10 (1%) were grade III, mostly bladder perforation or bleeding. Fifty-nine conversions (6.5%) to conventional transurethral resection (TUR) have been reported because of difficult locations of tumors or failure to extract the specimen. Several series, accounting for 763 patients, report about incidence of detrusor muscle in the specimen. Overall, 731 (96%) cases with detrusor muscle were computed. Tumor stage remained uncertain only in 12 (1.5%) cases. Follow-up data were available for 544 patients. Mean follow-up ranged from 9.3 to 40 months. Recurrence rate varied from 6% to 55%. Most of the recurrence occurred outside primary tumor site. Mean weighted follow-up across all series was 20 months, whereas overall recurrence rate was 23%.

CONCLUSIONS

Irrespective of the technique adopted, EBTUR is a safe procedure. The presence of detrusor muscle in the specimen is high if compared with historical series of conventional TUR. Indeed, recurrence rate is comparable. The objective advantage of a proper histological assessment suggests to perform EBTUR instead of conventional TUR, when feasible.

A Pilot Study of Vela Laser for En Bloc Resection of Papillary Bladder Cancer

INTRODUCTION

The present study evaluated the safety and efficacy of the Vela laser for en bloc resection of papillary bladder tumors.

MATERIALS AND METHODS

From January 2013 to August 2014, 38 patients underwent en bloc resection with the Vela laser and a 26F continuous flow resectoscope or 18F flexible cystoscope. Random cold forceps biopsy samples were also taken. The total operation time, pathologic result, and intraoperative and postoperative complications were recorded. Each patient was followed up for ≥ 1 year.

RESULTS

The average total operation time was 23 minutes. The en bloc resection of all tumors was successful, with 2 cases located at the bladder dome requiring the use of a flexible cystoscope for better management. No complications occurred during or after surgery. All resected tumors were intact with the detrusor muscle layer and architecture available for pathologic evaluation. One patient with stage T2b tumor underwent laparoscopic cystectomy 1 week after the initial surgery. At a median follow-up period of 21.8 months, the recurrence rate at 12 months was 21.6% (8 of 37).

CONCLUSION

The results of our study have shown that the Vela laser is an effective, feasible, and safe thulium laser for en bloc bladder tumor resection. It was associated with negligible complications and allows accurate pathologic evaluation. The Vela laser can serve as an alternative treatment method for nonmuscle-invasive bladder cancer or infiltrating tumor.

Office-based transurethral devascularisation of low grade non-invasive urothelial cancer using diode laser. A feasibility study

BACKGROUND AND OBJECTIVE

Frequent recurrence of non-muscle invasive bladder tumours (NMIBC) requiring transurethral resection of bladder tumour (TUR-BT) and lifelong monitoring makes the lifetime cost per patient the highest of all cancers. A new method is proposed for the removal of low grade NMIBCs in an office-based setting, without the need for sedation and pain control and where the patient can leave immediately after treatment.

STUDY DESIGN/PATIENTS AND METHODS

An in vitro model was developed to examine the dose/response relationship between laser power, treatment time, and distance between laser fibre and target, using a 980 nm diode laser and chicken meat. The relationship between depth and extent of tissue destruction and the laser settings was measured using microscopy and non-parametric statistical analysis. A patient with low grade stage Ta tumour and multiple comorbidity, and therefore not fit for general anaesthesia, had a tumour devascularised using the laser at the tumour base, in the outpatient department. The tumour was left in the bladder.

RESULTS

In the in vitro model, depth of tissue destruction increased with laser illumination up to 30 seconds, where median depth was 4.1 mm. With longer illumination the tissue destruction levelled off. The width of tissue destruction was 2-3 mm independent of laser illumination time. The in vivo laser treatments devascularised the tumour, which was later shed from the mucosa and passed out with the urine in the days following treatment. Pain score was 0 on a visual log scale (0-10). The tumour had completely disappeared two weeks after treatment.

CONCLUSION

This diode laser technique may provide almost pain-free office-based treatment of low grade urothelial cancer using flexible cystoscopes in conscious patients. A prospective randomised study will be scheduled to compare the technique with standard TUR-BT in the operating theatre.