Detection and recurrence rate of transurethral resection of bladder tumors by narrow-band imaging: Prospective, randomized comparison with white light cystoscopy

Comparison of narrow band imaging versus white light imaging in detecting non muscle invasive bladder cancer

BACKGROUND

In the present study, we compared Narrow Band Imaging (NBI) and White Light Cystoscopy (WLC) in Non-muscle invasive bladder cancer (NMIBC) for detection and its impact on recurrence.

MATERIALS AND METHODS

This prospective study was conducted in the department of Urology at a tertiary institution from August 2021 to April 2023. The main aim was to determine the benefit of addition of NBI during TURBT in NMIBC. All patients with Urinary Bladder Mass (size less than 5 cm on USG/CT) aged >18 years of age planned for TURBT were included.

RESULTS

Amongst 63 patients, the mean age was 59.84 ± 11.3 years; 80% were males. Sixty percent of patients had history of Tobacco consumption and Type II DM was the most common comorbidity (59%). Commonest symptom was gross haematuria. Posterior wall was most commonly involved and papillary lesions were commonest. A total of 125 lesions were identified on WLI, with mean 1.98 ± 1.75 and 78 additional lesions were identified only on NBI with mean 1.24 ± 1.63 lesions. Four patients had intra-operative complications. Five patients had recurrence at 6 weeks and eight patients had recurrence at 3 months. NBI had detected more lesions in patients who developed recurrence at 6 weeks and 3 months (mean: 1.41 and 1.43).

CONCLUSION

NBI has additive role in detecting NMIBC lesions missed on WLI. NBI has significant role in preventing recurrence at 3 months and more so by detecting high grade tumours.

Diagnostic and therapeutic effects of fluorescence cystoscopy and narrow-band imaging in bladder cancer: a systematic review and network meta-analysis

BACKGROUND

This review aims to compare the efficacies of fluorescence cystoscopy, narrow-band imaging (NBI), and white light cystoscopy in the treatment and diagnosis of bladder cancer.

METHODS

The authors searched PubMed, EMbase, Web of Science, and the Cochrane Library from January 1990 to April 2022. A total of 26 randomized controlled studies and 22 prospective single-arm studies were selected. Most patients had nonmuscle-invasive bladder cancer. The study protocol has been registered at PROSPERO.

RESULTS

In the pairwise meta-analysis, 5-aminolevulinic acid (5-ALA) reduced the short-term and long-term recurrence rates of bladder cancer compared with white light cystoscopy (WLC); however, no statistical difference was observed in intermediate-term recurrence rates (RR=0.79, 95% CI: 0.57-1.09). Hexaminolevulinic acid and NBI reduced short-term, intermediate-term, and long-term recurrence rates. The sensitivity of 5-ALA, hexaminolevulinic acid, NBI, and WLC for bladder cancer were 0.89 (95% CI: 0.81-0.94), 0.96 (95% CI: 0.92-0.98), 0.96 (95% CI: 0.92-0.98), and 0.75 (95% CI: 0.70-0.79), respectively; however, only NBI had the same specificity as WLC (0.74 vs. 0.74). Compared with WLC, 5-ALA improved the detection rate of carcinoma in situ and Ta stage bladder cancer but had no advantage in T1 stage tumors (OR=2.39, 95% CI:0.79-7.19). Hexaminolevulinic acid and NBI improved the detection rates of all nonmuscular-invasive bladder cancers. In the network meta-analysis, there was no significant difference in either recurrence or detection rates between 5-ALA, hexaminolevulinic acid, and NBI.

CONCLUSION

Fluorescence cystoscopy and NBI are advantageous for treating and diagnosing patients with nonmuscle-invasive bladder cancer.

The Impact of Cancer-Associated Fibroblasts on Drug Resistance, Stemness, and Epithelial-Mesenchymal Transition in Bladder Cancer: A Comparison between Recurrent and Non-Recurrent Patient-Derived CAFs

This study comparatively evaluated the possible effects of recurrent and non-recurrent patient-derived Cancer-Associated Fibroblasts (CAFs-R and -NR) on the bladder cancer cell line, EJ138. Both groups of CAFs increased cisplatin resistance and altered cell cycle distribution alongside induced resistance to apoptosis. Later, the scratch assay confirmed the cell migration-inducing effects of CAFs on cells. Nonetheless, only CAFs-R managed to increase sphere-formation and clonogenic levels in EJ138 cells, which were later validated by upregulating pluripotency transcription factors. Besides, CAFs-R also affected the expression levels of some of the EMT markers. Our study suggests that CAFs-R had stronger pro-tumorigenic effects on EJ138 cells.

Narrow band imaging versus white light cystoscopy alone for transurethral resection of non-muscle invasive bladder cancer

BACKGROUND

Disease recurrence and progression remain major challenges for the treatment of non-muscle invasive bladder cancer. Narrow band imaging (NBI) is an optical enhancement technique that may improve resection of non-muscle invasive bladder cancer and thereby lead to better outcomes for people undergoing the procedure.  OBJECTIVES: To assess the effects of NBI- and white light cystoscopy (WLC)-guided transurethral resection of bladder tumor (TURBT) compared to WLC-guided TURBT in the treatment of non-muscle invasive bladder cancer.

SEARCH METHODS

We performed a comprehensive literature search of 10 databases, including the Cochrane Library, the Cochrane Database of Systematic Reviews, MEDLINE, Embase, several clinical trial registries, and grey literature for published and unpublished studies, irrespective of language. The search was performed per an a priori protocol on 3 December 2021.

SELECTION CRITERIA

We included randomized controlled trials of participants with suspected or confirmed non-muscle invasive bladder cancer. Participants in the control group must have received WLC-guided TURBT alone (hereinafter simply referred to as 'WLC TURBT'). Participants in the intervention group had to have received NBI- and WLC-guided TURBT (hereinafter simply referred to as 'NBI + WLC TURBT').

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion/exclusion, performed data extraction, and assessed risk of bias. We conducted meta-analysis on time-to-event and dichotomous data using a random-effects model in RevMan, according to Cochrane methods. We rated the certainty of evidence for each outcome according to the GRADE approach. Primary outcomes were time to recurrence, time to progression, and the occurrence of a major adverse event, defined as a Clavien-Dindo III, IV, or V complication. Secondary outcomes included time to death from bladder cancer and the occurrence of a minor adverse event, defined as a Clavien-Dindo I or II complication.  MAIN RESULTS: We included eight studies with a total of 2152 participants randomized to the standard WLC TURBT or to NBI + WLC TURBT. A total of 1847 participants were included for analysis.  Based on limited confidence in the time-to-event data, we found that participants who underwent NBI + WLC TURBT had a lower risk of disease recurrence over time compared to participants who underwent WLC TURBT (hazard ratio 0.63, 95% CI 0.45 to 0.89; I2 = 53%; 6 studies, 1244 participants; low certainty of evidence). No studies examined disease progression as a time-to-event outcome or a dichotomous outcome. There was likely no difference in the risk of a major adverse event between participants who underwent NBI + WLC TURBT and those who underwent WLC TURBT (risk ratio 1.77, 95% CI 0.79 to 3.96; 4 studies, 1385 participants; low certainty of evidence). No studies examined death from bladder cancer as a time-to-event outcome or a dichotomous outcome. There was likely no difference in the risk of a minor adverse event between participants who underwent NBI + WLC TURBT and those who underwent WLC TURBT (risk ratio 0.88, 95% CI 0.49 to 1.56; I2 = 61%; 4 studies, 1385 participants; low certainty of evidence).  AUTHORS' CONCLUSIONS: Compared to WLC TURBT alone, NBI + WLC TURBT may lower the risk of disease recurrence over time while having little or no effect on the risks of major or minor adverse events.

Role of Macroscopic Image Enhancement in Diagnosis of Non-Muscle-Invasive Bladder Cancer: An Analytical Review

Early diagnosis of non-muscle-invasive bladder cancer (NMIBC) is of paramount importance to prevent morbidity and mortality due to bladder cancer. Although white light imaging (WLI) cystoscopy has long been considered the gold standard in the diagnosis of bladder cancer, it can miss lesions in a substantial percentage of patients and is very likely to miss carcinoma in situ and dysplasia. Tumor margin detection by WLI can be inaccurate. Moreover, WLI could, sometimes, be inadequate in distinguishing inflammation and malignancy. To improve the diagnostic efficacy of cystoscopy, various optical image enhancement modalities have been studied. These image enhancement modalities have been classified as macroscopic, microscopic, or molecular. Photodynamic diagnosis (PDD), narrow band imaging (NBI), and Storz image 1 S enhancement (formerly known as SPIES) are macroscopic image enhancement modalities. A relevant search was performed for literature describing macroscopic image enhancement modalities like PDD, NBI, and image 1 S enhancement. The advantages, limitations, and usefulness of each of these in the diagnosis of bladder cancer were studied. Photodynamic diagnosis requires intravesical instillation of a photosensitizing agent and a special blue light cystoscope system. PDD has been shown to be more sensitive than WLI in the detection of bladder cancer. It is superior to WLI in the detection of flat lesions. Bladder tumor resection (TURBT) by PDD results in more complete resection and reduced recurrence rates. PDD-guided TURBT may have some role in reducing the risk of progression. Narrow band imaging provides increased contrast between normal and abnormal tissues based on neovascularization, thereby augmenting WLI. NBI requires a special light source. There is no need for intravesical contrast instillation. NBI is superior to WLI in the detection of bladder cancer. The addition of NBI to WLI improves the detection of flat lesions like carcinoma in situ. NBI is not useful in predicting invasive tumors or grades of tumors. NBI-directed TURBT reduces recurrence rates and recurrence free survival. But its efficacy in retarding progression is unproven. Image 1 S-enhancement utilizes software-based image enhancement modes without the need for a special light source or intravesical contrast instillation. This system provides high-quality images and identifies additional abnormal-looking areas. Another advantage of this system is simultaneous side-by-side visualization of WLI and enhanced image, providing WLI images as the control for comparison. As with PDD, S-enhancement produces a lower rate of a missed bladder cancer diagnosis. The system significantly improves the diagnosis of NMIBC. The sensitivity and negative predictive value of image 1 S enhancement increase with the increase in cancer grade. A negative test by S-enhancement effectively rules out NMIBC. All the image enhancement modalities have proven their utility in improving detection and short-term cancer control. But none of these modalities have proven their utility in delaying progression, or in long-term cancer control. Cancer progression and long-term control are governed by the biological nature of cancer cells. Early detection by optical enhancement may not be of utility in this regard. Well-designed studies are needed to establish the efficacy of these modalities in the evaluation of patients with bladder cancer. The last word, in this regard, is yet to be written.

Explainable artificial intelligence (XAI): closing the gap between image analysis and navigation in complex invasive diagnostic procedures

Literature review

Cystoscopy is the gold standard for initial macroscopic assessments of the human urinary bladder to rule out (or diagnose) bladder cancer (BCa). Despite having guidelines, cystoscopic findings are diverse and often challenging to classify. The extent of the false negatives and false positives in cystoscopic diagnosis is currently unknown. We suspect that there is a certain degree of under-diagnosis (like the failure to detect malignant tumours) and over-diagnosis (e.g. sending the patient for unnecessary transurethral resection of bladder tumors with anesthesia) that put the patient at risk.

Conclusions

XAI robot-assisted cystoscopes would help to overcome the risks/flaws of conventional cystoscopy. Cystoscopy is considered a less life-threatening starting point for automation than open surgical procedures. Semi-autonomous cystoscopy requires standards and cystoscopy is a good procedure to establish a model that can then be exported/copied to other procedures of endoscopy and surgery. Standards also define the automation levels—an issue for medical product law. These cystoscopy skills do not give full autonomy to the machine, and represent a surgical parallel to ‘Autonomous Driving’ (where a standard requires a human supervisor to remain in the ‘vehicle’). Here in robotic cystoscopy, a human supervisor remains bedside in the ‘operating room’ as a ‘human‐in‐the‐loop’ in order to safeguard patients. The urologists will be able to delegate personal- and time-consuming cystoscopy to a specialised nurse. The result of automated diagnostic cystoscopy is a short video (with pre-processed photos from the video), which are then reviewed by the urologists at a more convenient time.

[Transurethral resection of bladder tumors (TURBT)]

Transurethral resection of bladder tumors (TURBT) is the standard of care for the diagnostics and primary treatment of bladder tumors. These are removed by fragmentation using loop diathermy. The resection area is coagulated for hemostasis. An important aspect is always a complete resection with an adequate amount of detrusor muscle in the specimen. Postoperative intravesical instillation of single-shot chemotherapy has been proven to reduce recurrence rates. Methods for improved tumor visualization (particularly photodynamic diagnostics) are used to enhance tumor detection rates particularly in multifocal tumors or carcinoma in situ (CIS). Thus, recurrence and progression rates can be reduced. Depending on the histological examination of the TURBT specimen, follow-up treatment for non-muscle invasive bladder tumors are adjuvant instillation treatment using chemotherapy or Bacillus Calmette-Guérin (BCG), second look TURBT and early cystectomy or for muscle invasive bladder tumors, radical cystectomy or (oncologically subordinate) trimodal treatment with renewed TURBT, radiotherapy and chemotherapy are indicated. Possible complications of TURBT include bleeding with bladder tamponade, extraperitoneal or intraperitoneal bladder perforation and infections of the urogenital tract.

European Association of Urology Guidelines on Non-muscle-invasive Bladder Cancer (Ta, T1, and Carcinoma in Situ)

CONTEXT

The European Association of Urology (EAU) has released an updated version of the guidelines on non-muscle-invasive bladder cancer (NMIBC).

OBJECTIVE

To present the 2021 EAU guidelines on NMIBC.

EVIDENCE ACQUISITION

A broad and comprehensive scoping exercise covering all areas of the NMIBC guidelines since the 2020 version was performed. Databases covered by the search included Medline, EMBASE, and the Cochrane Libraries. Previous guidelines were updated, and the level of evidence and grade of recommendation were assigned.

EVIDENCE SYNTHESIS

Tumours staged as Ta, T1 and carcinoma in situ (CIS) are grouped under the heading of NMIBC. Diagnosis depends on cystoscopy and histological evaluation of tissue obtained via transurethral resection of the bladder (TURB) for papillary tumours or via multiple bladder biopsies for CIS. For papillary lesions, a complete TURB is essential for the patient's prognosis and correct diagnosis. In cases for which the initial resection is incomplete, there is no muscle in the specimen, or a T1 tumour is detected, a second TURB should be performed within 2-6 wk. The risk of progression may be estimated for individual patients using the 2021 EAU scoring model. On the basis of their individual risk of progression, patients are stratified as having low, intermediate, high, or very high risk, which is pivotal to recommending adjuvant treatment. For patients with tumours presumed to be at low risk and for small papillary recurrences detected more than 1 yr after a previous TURB, one immediate chemotherapy instillation is recommended. Patients with an intermediate-risk tumour should receive 1 yr of full-dose intravesical bacillus Calmette-Guérin (BCG) immunotherapy or instillations of chemotherapy for a maximum of 1 yr. For patients with high-risk tumours, full-dose intravesical BCG for 1-3 yr is indicated. For patients at very high risk of tumour progression, immediate radical cystectomy should be considered. Cystectomy is also recommended for BCG-unresponsive tumours. The extended version of the guidelines is available on the EAU website at https://uroweb.org/guideline/non-muscle-invasive-bladder-cancer/.

CONCLUSIONS

These abridged EAU guidelines present updated information on the diagnosis and treatment of NMIBC for incorporation into clinical practice.

PATIENT SUMMARY

The European Association of Urology has released updated guidelines on the classification, risk factors, diagnosis, prognostic factors, and treatment of non-muscle-invasive bladder cancer. The recommendations are based on the literature up to 2020, with emphasis on the highest level of evidence. Classification of patients as having low, intermediate, or and high risk is essential in deciding on suitable treatment. Surgical removal of the bladder should be considered for tumours that do not respond to bacillus Calmette-Guérin (BCG) treatment and tumours with the highest risk of progression.

Impact of enhanced optical techniques at time of transurethral resection of bladder tumour, with or without single immediate intravesical chemotherapy, on recurrence rate of non-muscle-invasive bladder cancer: a systematic review and network meta-analysis of randomized trials

OBJECTIVE

To assess whether single immediate intravesical chemotherapy (SIIC) adds value to bladder tumour management in combination with novel optical techniques: enhanced transurethral resection of bladder tumour (TURBT).

METHODS

A systematic search was performed using the PubMed and Web of Science databases in September 2020 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) extension statement for network meta-analyses. Studies that compared recurrence rates among intervention groups (TURBT with photodynamic diagnosis [PDD] ± SIIC, narrow-band imaging [NBI] ± SIIC, or white-light cystoscopy [WLC] + SIIC) and a control group (TURBT with WLC alone) were included. We used the Bayesian approach in the network meta-analysis.

RESULTS

Twenty-two studies (n = 4519) met our eligibility criteria. Out of six different interventions including three different optical techniques, compared to WLC alone, blue-light cystoscopy (BLC) plus SIIC (odds ratio [OR] 0.349, 95% credible interval [CrI] 0.196-0.601) and BLC alone (OR 0.668, 95% CrI 0.459-0.931) were associated with a significantly lower likelihood of 12-month recurrence rate. In the sensitivity analysis, out of eight different interventions compared to WLC alone, PDD by 5-aminolevulinic acid plus SIIC (OR 0.327, 95% CrI 0.159-0.646) and by hexaminolevulinic acid plus SIIC (OR 0.376, 95% CrI 0.172-0.783) were both associated with a significantly lower likelihood of 12-month recurrence rate. NBI with and without SIIC was not associated with a significantly lower likelihood of 12-month recurrence rate (OR 0.385, 95% CrI 0.105-1.29 and OR 0.653, 95% CrI 0.343-1.15).

CONCLUSION

Blue-light cystoscopy during TURBT with concomitant SIIC seems to yield superior recurrence outcomes in patients with non-muscle-invasive bladder cancer. The use of PDD was able to reduce the 12-month recurrence rate; moreover, concomitant SIIC increased this risk benefit by a 32% additional reduction in odds ratio. Although using PDD could reduce the recurrence rate, SIIC remains necessary. Moreover, ranking analysis showed that both PDD and NBI, plus SIIC, were better than these techniques alone.

Systematic review and meta-analysis of narrow band imaging for non-muscle-invasive bladder cancer

To assess the effect of narrow band imaging-guided transurethral resection of bladder tumor compared with white light on recurrence rates in non-muscle-invasive bladder cancer. A systematic review of the literature from inception to November 2020 using Medline, EMBASE and CENTRAL was undertaken. Randomized controlled trials comparing transurethral resection of bladder tumor undertaken with narrow band imaging with those undertaken with white light that reported recurrence rates of at least 12 months were included in the analysis. Primary outcomes were recurrence rates at 12 and 24 months. Secondary outcomes were reported adverse effects. A total of 387 abstracts were screened, of which 14 full text identified and three studies included in the meta-analysis (921 patients). Meta-analysis did not show a statistically significant benefit to narrow band imaging at 12 months; risk ratio 0.75 (95% confidence interval 0.50-1.14, P = 0.18, I²  = 61%). No included studies provided recurrence data beyond 12 months. Adverse effects were reported in one study and no significant difference of complication rate was observed between the two groups. Risk of bias was assessed to be generally low, and grading of recommendations assessment development and evaluations were of high certainty. This meta-analysis of randomized controlled trials shows no difference in recurrence rates using narrow band imaging, although a trend in its favor was identified. Limitations include the varied reporting and administration of adjuvant therapies. Further well-designed trials are required to examine the benefit of this technology.

Enhanced Visualization Methods for First Transurethral Resection of Bladder Tumour in Suspected Non-muscle-invasive Bladder Cancer: A Health Technology Assessment

BACKGROUND

Bladder cancer begins in the innermost lining of the bladder wall and, on histological examination, is classified as one of two types: non-muscle-invasive bladder cancer (NMIBC) or muscle-invasive bladder cancer. Transurethral resection of bladder tumour (TURBT) is the standard treatment for people with NMIBC, but the high rate of cancer recurrence after first TURBT is a challenge that physicians and patients face. Tumours seen during follow-up may have been missed or incompletely resected during first TURBT. TURBT is conventionally performed using white light to see the tumours. However, small papillary or flat tumours may be missed with the use of white light alone. With the emergence of new technologies to improve visualization during TURBT, better diagnostic and patient outcomes may be expected. We conducted a health technology assessment of two enhanced visualization methods, both as an adjunct to white light to guide first TURBT for people with suspected NMIBC-hexaminolevulinate hydrochloride (HAL), a solution that is instilled into the bladder to make tumours fluoresce under blue-violet light, and narrow band imaging (NBI), a technology that filters light into wavelengths that can be absorbed by hemoglobin in the tumours, making them appear darker. Our assessment included an evaluation of effectiveness, safety, cost-effectiveness, and the budget impact of publicly funding these new technologies to improve patient outcomes following first TURBT. The use of NBI in diagnostic cystoscopy was out of scope for this health technology assessment.

METHODS

We performed a systematic literature search of the clinical evidence from inception to April 15, 2020. We searched for randomized controlled trials (RCTs) that compared the outcomes of first TURBT with the use of HAL or NBI, both as an adjunct to white light, with the outcomes of first TURBT using white light alone, or studies that made such comparison between HAL and NBI. We conducted pairwise meta-analyses using a fixed effects model where head-to-head comparisons were available. In the absence of any published RCT for comparison between HAL and NBI, we indirectly compared the two technologies through indirect treatment comparison (ITC) analysis. We assessed the risk of bias of each included study using the Cochrane risk-of-bias tool. We assessed the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic economic literature search and conducted a cost-utility analysis with a 15-year time horizon from a public payer perspective. We also analyzed the budget impact of publicly funding HAL and NBI as an adjunct to white light in people undergoing their first TURBT for suspected non-muscle-invasive bladder cancer in Ontario.

RESULTS

In the clinical evidence review, we identified 8 RCTs that used HAL or NBI as an adjunct to white light during first TURBT. Pairwise meta-analysis of HAL studies showed that HAL-guided TURBT as an adjunct to white light significantly reduces recurrence rate at 12 months compared with TURBT using white light alone (risk ratio 0.70, 95% confidence interval [CI] 0.51-0.95) (GRADE: Moderate). Five-year recurrence-free survival was significantly higher when HAL was used as an adjunct to white light than when white light was used alone (GRADE: Moderate). There was little to no difference in the tumour progression rate (GRADE: Moderate).Meta-analysis of NBI studies did not show a significant difference between NBI-guided TURBT as an adjunct to white light and TURBT using white light alone in reducing the rate of recurrence at 12 months (risk ratio 0.94, 95% CI 0.75-1.19) (GRADE: Moderate). No evidence on the effect on recurrence-free survival or tumour progression rate was identified for NBI-guided TURBT. The indirect estimate from the network analysis showed a trend toward a lower rate of recurrence after HAL-guided TURBT than after NBI-guided TURBT but the difference was not statistically significant (risk ratio 0.76, 95% CI 0.51-1.11) (GRADE: Low). Studies showed that use of HAL or NBI during TURBT was generally safe.The incremental cost-effectiveness ratio of HAL-guided TURBT compared with NBI-guided TURBT, both as an adjunct to white light, is $12,618 per quality-adjusted life-year (QALY) gained. Compared with TURBT using white light alone and using adjunct NBI, the probability of HAL-guided TURBT being cost-effective is 69.1% at a willingness-to-pay value of $50,000 per QALY gained and 74.6% at a willingness-to-pay of $100,000 per QALY gained. The annual budget impact of publicly funding HAL-guided TURBT in Ontario over the next 5 years ranges from an additional $0.6 million in year 1 to $2.5 million in year 5.

CONCLUSIONS

First TURBT guided by HAL as an adjunct to white light likely reduces the rate of recurrence at 12 months and increases 5-year recurrence-free survival when compared with first TURBT using white light alone. There is likely little to no difference in the tumour progression rate. First TURBT guided by NBI as an adjunct to white light likely results in little to no difference in the rate of recurrence at 12 months when compared with first TURBT using white light alone. Based on an indirect comparison, there may be little to no difference in cancer recurrence rate between HAL-guided and NBI-guided first TURBT. Use of HAL or NBI during first TURBT is generally safe. For people undergoing their first TURBT for suspected non-muscle-invasive bladder cancer, using HAL as an adjunct to white light is likely to be cost-effective compared with using white light alone or with using NBI as an adjunct to white light. We estimate that publicly funding HAL as an adjunct to white light to guide first TURBT for people in Ontario with suspected NMIBC would result in additional costs of between $0.6 million and $2.5 million per year over the next 5 years.

Novel Visualization Methods Assisted Transurethral Resection for Bladder Cancer: An Updated Survival-Based Systematic Review and Meta-Analysis

Background

Photodynamic diagnosis and narrow-band imaging could help improve the detection rate in transurethral resection (TUR) of bladder cancer. It remained controversial that the novel visualization method assisted transurethral resection (VA-TUR) could elongate patients' survival compared to traditional TUR.

Methods

We performed electronic and manual searching until December 2020 to identify randomized controlled trials comparing VA-TUR with traditional TUR, which reported patients' survival data. Two reviewers independently selected eligible studies, extracted data, assessed the risk of bias. Meta-analysis was conducted according to subgroups of types of visualization methods (A) and clinical stage of participants. Publication bias was detected.

Results

We included 20 studies (reported in 28 articles) in this review. A total of 6,062 participants were randomized, and 5,217 participants were included in the analysis. Only two studies were assessed at low risk of bias. VA-TURB could significantly improve the recurrence-free survival (RFS) (HR = 0.72, 95% CI: 0.66 to 0.79, P <0.00001, I² = 42%) and progression-free survival (PFS) (HR = 0.62, 95% CI: 0.46 to 0.82, P <0.0008, I² = 0%) compared with TUR under white light. The results remain stable whatever the type of visualization method. The difference could be observed in the non-muscle-invasive bladder cancer (NMIBC) population (P <0.05) but not in the mixed population with muscle-invasive bladder cancer (MIBC) participants (P >0.05).

Conclusion

VA-TUR could improve RFS and PFS in NMIBC patients. No significant difference is found among different types of VA-TUR. VA-TUR may be not indicated to MIBC patients.

[Systemic treatment of bladder cancer]

Cisplatin-based chemotherapy regimens represent the standard of care in patients with locally advanced or metastatic urothelial carcinoma of the bladder. However, many patients are ineligible for cisplatin due to comorbidities or performance status. Immunotherapy with checkpoint inhibitors (CPI) has become a well-established treatment alternative in metastatic bladder cancer. The following review discusses current literature and guideline recommendations based on two case studies, in order to provide practical know-how about therapy sequences and treatment processes.

Cold Atmospheric Plasma, a Novel Approach against Bladder Cancer, with Higher Sensitivity for the High-Grade Cell Line

Simple Summary

Bladder cancer has a high incidence and mortality. Besides this, currently available therapies for this type of cancer have low efficacy and show considerable adverse effects, urging the need of new therapeutic approaches. Cold Atmospheric Plasma treatment presents itself as a promising alternative, having demonstrated antitumor effects against several types of cancer. The present work arises from a multidisciplinary team, namely, medical doctors and researchers, in an attempt to find new therapeutic strategies to fight bladder cancer. Therefore, our main objective is to evaluate Cold Atmospheric Plasma effects against bladder cancer, as well as the mechanisms by which it exerts its effects. The results obtained demonstrate that Cold Atmospheric Plasma treatment has a promising antitumor effect on bladder cancer, with higher sensitivity for the high-grade cell line. This new approach using Cold Atmospheric Plasma for the treatment of bladder cancer presents enormous clinical benefits, since it is able to selectively treat the tumor tissue, sparing the normal urothelium, with an additional glaring positive economic impact, since it entails a decrease in the cost of therapy in comparison with conventional therapeutic options.

Abstract

Antitumor therapies based on Cold Atmospheric Plasma (CAP) are an emerging medical field. In this work, we evaluated CAP effects on bladder cancer. Two bladder cancer cell lines were used, HT-1376 (stage III) and TCCSUP (stage IV). Cell proliferation assays were performed evaluating metabolic activity (MTT assay) and protein content (SRB assay). Cell viability, cell cycle, and mitochondrial membrane potential (Δψ_m) were assessed using flow cytometry. Reactive oxygen and nitrogen species (RONS) and reduced glutathione (GSH) were evaluated by fluorescence. The assays were carried out with different CAP exposure times. For both cell lines, we obtained a significant reduction in metabolic activity and protein content. There was a decrease in cell viability, as well as a cell cycle arrest in S phase. The Δψ_m was significantly reduced. There was an increase in superoxide and nitric oxide and a decrease in peroxide contents, while GSH content did not change. These results were dependent on the exposure time, with small differences for both cell lines, but overall, they were more pronounced in the TCCSUP cell line. CAP showed to have a promising antitumor effect on bladder cancer, with higher sensitivity for the high-grade cell line.

Narrow-band imaging assisted cystoscopy in the follow-up of patients with transitional cell carcinoma of the bladder: a randomized study in comparison with white light cystoscopy

PURPOSE

To evaluate the diagnostic accuracy of a second look narrow-band imaging (NBI) cystoscopy in the follow-up of patients with NMIBC as compared to a second white light cystoscopy (WLI).

PATIENTS AND METHODS

From August 2013 to October 2014, 600 patients with history of non-muscle invasive bladder cancer (NMIBC), who presented for follow-up cystoscopy at an academic outpatient clinic, were randomized to flexible WLI-cystoscopy plus second look NBI-cystoscopy (n = 300) or flexible WLI-cystoscopy plus second look WLI-cystoscopy (n = 300) in the same session. We analysed the detection rate of bladder tumours in second look cystoscopy as primary endpoint. In addition, we evaluated recurrence rates before study enrolment and after transurethral resection (TUR-BT) in each group.

RESULTS

In 600 patients with a history of NMIBC, 78 out of 300 patients (26%) with WLI-NBI-cystoscopy and 70 out of 300 patients (23%) with WLI-WLI-cystoscopy were diagnosed with cancer recurrence (p = 0.507). Overall, WLI-NBI detected 404 and WLI-WLI 234 lesions, respectively. The second look cystoscopy detected 57 additional cancer lesions: 45 tumours in 18 patients with WLI-NBI and 12 tumours in 9 patients with WLI-WLI (p = 0.035). After initial examination without tumour detection an improvement was determined by the second cystoscopy in 3 patients (75 vs. 78 pat.) with WLI-NBI and in only one patient (69 vs. 70 pat.) with WLI-WLI (p = 0.137). Second look cystoscopy did not influence the detection of carcinoma in situ in both groups (p = 0.120). After TUR-BT the median recurrence-free survival was 4 months in 57 recurring patients (73%) in the group with WLI-NBI- and 6 months in 56 patients (80%) with WLI-WLI-cystoscopy (p = 0.373), respectively.

CONCLUSION

Our study showed no differences in per-patient tumour detection between WLI and NBI. Although NBI has significant benefits for detecting individual lesions overlooked by WLI-cystoscopy, this did not positively affect recurrence-free survival after transurethral resection.

European Association of Urology Guidelines on Non-muscle-invasive Bladder Cancer (TaT1 and Carcinoma In Situ) - 2019 Update

CONTEXT

This overview presents the updated European Association of Urology (EAU) guidelines for non-muscle-invasive bladder cancer (NMIBC), TaT1, and carcinoma in situ (CIS).

OBJECTIVE

To provide practical recommendations on the clinical management of NMIBC with a focus on clinical presentation and recommendations.

EVIDENCE ACQUISITION

A broad and comprehensive scoping exercise covering all areas of the NMIBC guidelines has been performed annually since the last published version in 2017. Databases covered by the search included Medline, EMBASE, and the Cochrane Libraries. Previous guidelines were updated, and the level of evidence and grade of recommendation were assigned.

EVIDENCE SYNTHESIS

Tumours staged as Ta, T1, and/or CIS are grouped under the heading of NMIBC. Diagnosis depends on cystoscopy and histological evaluation of the tissue obtained by transurethral resection (TURB) in papillary tumours or by multiple bladder biopsies in CIS. In papillary lesions, a complete TURB is essential for the patient's prognosis and correct diagnosis. Where the initial resection is incomplete, where there is no muscle in the specimen, or where a T1 tumour is detected, a second TURB should be performed within 2-6 wk. The risks of both recurrence and progression may be estimated for individual patients using the European Organisation for Research and Treatment of Cancer (EORTC) scoring system. Stratification of patients into low-, intermediate-, and high-risk groups is pivotal to the recommendation of adjuvant treatment. In patients with tumours presumed to be at a low risk and in those presumed to be at an intermediate risk with a low previous recurrence rate and an expected EORTC recurrence score of <5, one immediate chemotherapy instillation is recommended. Patients with intermediate-risk tumours should receive 1 yr of full-dose bacillus Calmette-Guérin (BCG) intravesical immunotherapy or instillations of chemotherapy for a maximum of 1 yr. In patients with high-risk tumours, full-dose intravesical BCG for 1-3 yr is indicated. In patients at the highest risk of tumour progression, immediate radical cystectomy should be considered. Cystectomy is recommended in BCG-unresponsive tumours. The extended version of the guidelines is available at the EAU website: https://uroweb.org/guideline/non-muscle-invasive-bladder-cancer/.

CONCLUSIONS

These abridged EAU guidelines present updated information on the diagnosis and treatment of NMIBC for incorporation into clinical practice.

PATIENT SUMMARY

The European Association of Urology Non-muscle-invasive Bladder Cancer (NMIBC) Panel has released an updated version of their guidelines, which contains information on classification, risk factors, diagnosis, prognostic factors, and treatment of NMIBC. The recommendations are based on the current literature (until the end of 2018), with emphasis on high-level data from randomised clinical trials and meta-analyses. Stratification of patients into low-, intermediate-, and high-risk groups is essential for deciding appropriate use of adjuvant intravesical chemotherapy or bacillus Calmette-Guérin (BCG) instillations. Surgical removal of the bladder should be considered in case of BCG-unresponsive tumours or in NMIBCs with the highest risk of progression.

Current concept of transurethral resection of bladder cancer: from re-transurethral resection of bladder cancer to en-bloc resection

PURPOSE OF REVIEW

Transurethral resection of bladder cancer (TURB) is the critical step in the management of nonmuscle invasive bladder cancer (NMIBC). This review presents new improvements in the strategy and technique of TURB as well as in technological developments used for tumour visualization and removal.

RECENT FINDINGS

The goal of TURB is to perform complete resection of NMIBC. Tumor visualization during procedure can be improved by enhanced optical technologies. Fluorescence-guided photodynamic diagnosis (PDD) and narrow-band imaging (NBI) used during TURB can improve tumour detection and potentially reduce recurrence rate, their influence on progression, however, remains controversial. TURB can be performed using monopolar or bipolar electrocautery without significant differences in results or safety. To overcome limitations of traditional TURB, the technique of en-bloc resection was introduced to improve the quality of tumour removal. In selected cases, an early re-resection (re-TURB) within 2-6 weeks after initial procedure is recommended.

SUMMARY

TURB is a fundamental step in diagnosis and treatment of NMIBC. Urologists should be aware of promising innovations including new imaging and surgical techniques and their potential benefits. Hopefully, new technologies and performance of TURB bring improved outcomes, which can alter the indication criteria for re-TURB.

Methods for bladder cancer diagnosis - The role of autofluorescence and photodynamic diagnosis

Bladder cancer is one of the most common Genito-urinary malignant tumors in humans. Improved diagnostic and therapeutic methods that aim to reduce rates of recurrence and progression of bladder cancer are needed. In current publications, one can find information on such methods as Raman spectroscopy, ultraviolet autofluorescence microscopy, confocal laser endoscopy, photoacoustic imaging, molecular imaging, multi-photon microscopy and many other new diagnostic techniques. These methods do not show significant adverse effects and are procedures well tolerated by patients as they use mostly physical phenomena that are neutral towards the human body. This review highlights the techniques of autofluorescence (AF) or laser induced fluorescence (LIF) and photodynamic diagnostics (PDD) which have been widely clinically studied for many years as a complement to cystoscopy. These methods can be performed during standard cystoscopy and they can be used in routine practice. This review shows that Autofluorescent and Photodynamic diagnostics are effective and have great potential in enhancing the diagnosis of bladder cancer. However, more research should be performed to help realize their full potential.

Enhanced Endoscopy in Bladder Cancer

PURPOSE OF REVIEW

Endoscopy coupled with targeted resections represents a cornerstone in the diagnosis, staging, and treatment of patients with bladder cancer. Direct visualization can be challenging and imprecise due to patient-, tumor-, and surgeon-specific factors. We will review contemporary endoscopic technologies and techniques used to improve our ability to safely identify and resect malignant lesions in patients with bladder cancer.

RECENT FINDINGS

Enhanced endoscopic imaging technology may improve detection rates for bladder cancer throughout the upper and lower urinary tract, which may lead to improvements in recurrence and progression rates for non-muscle invasive bladder cancer (NMIBC). New techniques including narrow-band imaging (NBI), photodynamic diagnosis (PDD), Storz Professional Image Enhancement System (SPIES), optical coherence tomography (OCT), and others have shown benefit and may further improve our ability to detect and stage bladder tumors. Enhanced endoscopy technologies have already demonstrated value in improving the sensitivity of bladder cancer detection and early results suggest they may improve short- and long-term oncologic outcomes.