Narrow-band imaging flexible cystoscopy in the detection of primary non-muscle invasive bladder cancer: a “second look” matters?

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.

Cystoscopy Accuracy in Detecting Bladder Tumors: A Prospective Video-Confirmed Study

BACKGROUND

Bladder cancer ranks as the 10th most common cancer globally. The diagnosis of bladder tumors typically involves cystoscopy.

OBJECTIVE

This study aimed to evaluate the sensitivity and specificity of cystoscopy in detecting bladder tumors within a surveillance program following a bladder cancer diagnosis.

DESIGN, SETTING, AND PARTICIPANTS

This study utilized recordings of cystoscopies conducted at the Department of Urology, Zealand University Hospital, between July 2021 and November 2022. Clinical observations were cross-referenced with pathological results or follow-up cystoscopies. Clinically negative cystoscopies were further scrutinized for potential overlooked tumors.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Sensitivity and specificity of cystoscopy were assessed through ROC curve analysis.

RESULTS AND LIMITATIONS

A total of 565 cystoscopies were recorded, with 135 indicating clinical positivity. Among 181 cystoscopies with clinically negative results that underwent a follow-up cystoscopy, 17 patients (9.4%) were subsequently diagnosed with bladder cancer, with the lesions identified in the initial cystoscopy. The sensitivity and specificity of cystoscopy in these cases were 81% and 73%, respectively.

CONCLUSION

This trial underscores the underdiagnosis and undertreatment of bladder tumors within the current surveillance program. Additionally, aggressive malignant lesions may be overlooked, heightening the risk of disease progression. Therefore, it is recommended that cystoscopies be complemented by other diagnostic methods to ensure accurate diagnosis and proper patient treatment.

PATIENT SUMMARY

This study involved 316 patients who underwent video-recorded cystoscopies and subsequent follow-up. Of these patients, 181 initially exhibited no clinical signs of bladder cancer. However, upon reviewing the recorded cystoscopy, bladder cancer was identified in 17 patients (9.4%).

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.

Noninvasive studies may have potential to replace cystoscopy in non-muscle invasive bladder cancer follow-up

Bladder cancer has a high recurrence rate which requires frequent follow-up. Cystoscopy is currently the gold standard for follow-up which is invasive and undesirable procedure for patients. We aimed to investigate the feasibility of noninvasive studies for follow-up of non-muscle invasive bladder cancer. This retrospective study was done for non-muscle invasive bladder cancer patients with abnormal lesion at follow up cystoscopy, therefore those needed transurethral resection of bladder tumor (TUR-BT). Inclusion criteria was patients who had preoperative bladder magnetic resonance imaging (MRI) within 1 month to TUR-BT and urine cytology results. MRI, urine cytology, and surgical pathology results were analyzed for sensitivity, specificity, positive and negative predictive values, accuracy, diagnostic odds ratio, and number needed to misdiagnose for the diagnostic performance of non-invasive studies. From total of 2,258 TUR-BT cases, 1,532 cases of primary TUR-BT and 481 cases which bladder MRI were not done was excluded. Finally, 245 cases of TUR-BT were included. Combined urine cytology and bladder MRI showed 96% sensitivity, 43% specificity, 89% positive and 67% negative predictive values, 87% accuracy, 16.2 diagnostic odds ratio, and 7.4 number needed to misdiagnose values. Among nine false-negative cases, three (1.2%) were missed by the radiologist, two (0.8%) had an empty bladder during magnetic resonance imaging, and three (1.2%) had gross hematuria which needed cystoscopy despite of bladder MRI or urine cytology result. Only one case (0.4%) was missed based on symptoms and noninvasive tests. However, none of the false-negative cases showed rapid extensive progression requiring radical or partial cystectomy. The combination of bladder MRI and urine cytology was comparable to cystoscopy for the follow-up of recurred lesions in non-muscle invasive bladder cancer patients for sensitivity, but not for specificity. However, it may reduce the need for cystoscopy and allowing patients to have choices for follow up diagnostic methods. Also, additional imaging tests to evaluate kidney, ureter and peri-vesical lesions can be reduced.

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.

Performance of Narrow Band Imaging (NBI) and Photodynamic Diagnosis (PDD) Fluorescence Imaging Compared to White Light Cystoscopy (WLC) in Detecting Non-Muscle Invasive Bladder Cancer: A Systematic Review and Lesion-Level Diagnostic Meta-Analysis

Despite early detection and regular surveillance of non-muscle invasive bladder cancer (NMIBC), recurrence and progression rates remain exceedingly high for this highly prevalent malignancy. Limited visualization of malignant lesions with standard cystoscopy and associated false-negative biopsy rates have been the driving force for investigating alternative and adjunctive technologies for improved cystoscopy. The aim of our systematic review and meta-analysis was to compare the sensitivity, specificity, and oncologic outcomes of photodynamic diagnosis (PDD) fluorescence, narrow band imaging (NBI), and conventional white light cystoscopy (WLC) in detecting NMIBC. Out of 1,087 studies reviewed, 17 prospective non-randomized and randomized controlled trials met inclusion criteria for the study. We demonstrated that tumor resection with either PDD and NBI exhibited lower recurrence rates and greater diagnostic sensitivity compared to WLC alone. NBI demonstrated superior disease sensitivity and specificity as compared to WLC and an overall greater hierarchical summary receiver operative characteristic. Our findings are consistent with emerging guidelines and underscore the value of integrating these enhanced technologies as a part of the standard care for patients with suspected or confirmed NMIBC.

The use of artificial intelligence for the diagnosis of bladder cancer: a review and perspectives

PURPOSE OF REVIEW

White light cystoscopy is the current standard for primary diagnosis and surveillance of bladder cancer. However, cancer changes can be subtle and may be easily missed. With the advancement of deep learning (DL), image recognition by artificial intelligence (AI) proves a high accuracy for image-based diagnosis. AI can be a solution to enhance bladder cancer diagnosis on cystoscopy.

RECENT FINDINGS

An algorithm that classifies cystoscopic images into normal and tumour images is essential for AI cystoscopy. To develop this AI-based system requires a training dataset, an appropriate type of DL algorithm for the learning process and a specific outcome classification. A large data volume with minimal class imbalance, data accuracy and representativeness are pre-requisite for a good dataset. Algorithms developed during the past two years to detect bladder tumour achieved high performance with a pooled sensitivity of 89.7% and specificity of 96.1%. The area under the curve ranged from 0.960 to 0.980, and the accuracy ranged from 85.6 to 96.9%. There were also favourable results in the various attempts to enhance detection of flat lesions or carcinoma-in-situ.

SUMMARY

AI cystoscopy is a possible solution in clinical practice to enhance bladder cancer diagnosis, improve tumour clearance during transurethral resection of bladder tumour and detect recurrent tumours upon surveillance.

Bladder cancer in the time of machine learning: Intelligent tools for diagnosis and management

Machine learning (ML) is the subfield of artificial intelligence (AI), born from the marriage between statistics and computer science, with the unique purpose of building prediction algorithms able to improve their performances by automatically learning from massive data sets. The availability of ever-growing computational power and highly evolved pattern recognition software has led to the spread of ML-based systems able to perform complex tasks in bioinformatics, medical imaging, and diagnostics. These intelligent tools could be the answer to the unmet need for non-invasive and patient-tailored instruments for the diagnosis and management of bladder cancer (BC), which are still based on old technologies and unchanged nomograms. We reviewed the most significant evidence on ML in the diagnosis, prognosis, and management of bladder cancer, to find out if these intelligent technologies are ready to be introduced into the daily clinical practice of the urologist.

Fluorescence Emitted by Papanicolaou-Stained Urothelial Cells Improves Sensitivity of Urinary Conventional Cytology for Detection of Urothelial Tumors

Background

Urinary conventional cytology (UCCy) is easy to perform, but its low sensitivity, especially for low-grade urothelial neoplasms (LGUNs), limits its indications in the management of patients at risk of bladder cancer. The authors aim at obtaining a complementary test that would effectively increase the sensitivity of UCCy on voided urines by analyzing fluorescence of Papanicolaou-stained urothelial cells with no change of method in slide preparation.

Methods

In this retrospective study of 155 patients, 91 Papanicolaou-stained voided urines were considered satisfactory under fluorescence microscopy (FMi). The results of FMi were compared with UCCy (using transmission microscopy) and correlated to cystoscopy, histology and follow-up data.

Results

The results are given for all patients and for two groups of them according to the patients’ main complaints (group 1: 33 patients followed up for a previously treated bladder tumor; group 2: 58 patients with persistent urinary symptoms). Overall negative predictive value (NPV) and sensitivity of FMi were 100% vs. 73.7% and 64.3% respectively for UCCy (P = 0.0001). Sensitivity of FMi for LGUN was unexpectedly high with a value of 100% vs. 46.2% for UCCy (P = 0.0002). FMi was significantly superior to UCCy for detecting urothelial tumors in every group of patients and would allow a better characterization of atypical urothelial cells (AUCs) defined by the Paris System for Reporting Urine Cytology (TPS).

Conclusions

Because of its sensitivity and NPV of 100%, FMi could complement UCCy to screen voided urines allowing a better detection of primary urothelial tumors or early recurrences of previously treated urothelial carcinoma. Moreover, this “dual screening” would allow completing efficiently cystoscopy to detect flat dysplasia, carcinoma in situ (CIS) and extra bladder carcinoma.

Clinical application of drug sensitive gene detection in postoperative instillation for non-muscle invasive bladder cancer

Background

Bladder cancer is the most common malignant tumor of the urinary system. One of the biological characteristics of NMIBC is the high recurrence rate after surgery. The implementation of this project aimed to investigate the role of pharmacogenomic testing-guided intravesical perfusion of chemotherapeutic agents in the postoperative perfusion therapy for non-muscle invasive bladder cancer.

Method

From January 2015 to December 2016, 298 patients with non-muscle-invasive bladder cancer were enrolled in this prospective study. These patients received chemotherapy drugs after electrotherapy. According to the presence or absence of tumor susceptibility gene detection after surgery, they were divided into two groups, including the drug sensitive group(N = 44) and the control group(N = 254). The drug sensitive group received bladder infusion therapy with sensitive chemotherapy drugs based on drug sensitivity gene detection results. The control group received intravesical instillation of pirarubicin. The preoperative general data and tumor grade of patients were recorded. Cystoscopy was performed before and every 3 months after surgery. The chest CT, upper abdomen CT, renal function, and urinary routine tests were performed. Tumor recurrence, metastasis and tumor-related death were recorded and evaluated during follow-up.

Results

The drug sensitive group, which selected high-sensitivity drugs for intravesical instillation therapy based on gene expression, has a significantly lower relapse rate (11.36% vs 37.40%, P < 0.05) and a significantly longer time to relapse (17.80 ± 7.20 month vs11.20 ± 6.10 month, P < 0.05) compared with the control group. There were no significant differences in the time of mortality and death time between two groups.

Conclusion

The pharmacogenomic testing-directed bladder instillation of chemotherapeutic drugs may be more effective than empiric drug administration in reducing the recurrence rate of non-muscle-invasive bladder cancer.

Diagnostic accuracy of photodynamic diagnosis with 5-aminolevulinic acid, hexaminolevulinate and narrow band imaging for non-muscle invasive bladder cancer

Objective: To assess the diagnostic test accuracy (DTA) of photodynamic diagnosis with 5-aminolaevulinic acid (5-ALA), hexylaminolevulinate (HAL) and narrow band imaging (NBI) for non-muscle-invasive bladder cancer (NMIBC), with white light-guided cystoscopy (WLC) as reference standard. Materials and Methods: A systematic review and narrative synthesis was performed in accordance with PRISMA. Major electronic databases were searched until 20th May 2019. All studies assessing the DTA of 5-ALA, HAL and NBI compared with WLC at patient and lesion-level were included. Relevant sensitivity analyses and risk of bias (RoB) assessment were undertaken. Results: 26 studies recruiting 3979 patients were eligible for inclusion. For patient-level analysis, NBI appeared to be the best (median sensitivity (SSY) 100%, median specificity (SPY) 68.45%, median positive predictive value (PPV) 90.75%, median negative predictive value (NPV) 100% and median false positive rate (FPR) 31.55%), showing better DTA outcomes than either HAL or 5-ALA. For lesion-level analysis, median SSY across NBI, HAL and 5-ALA were 93.08% (IQR 87.04-98.81%), 93.16% (IQR 91.48-97.04%) and 94.42% (IQR 82.37-95.73%) respectively. As for FPR, median values for NBI, HAL and 5-ALA were 20.40% (IQR 13.68-27.36%), 17.43% (IQR 12.79-22.40%) and 28.12% (IQR 22.08-42.39%), respectively. Sensitivity analyses based on studies with low to moderate RoB and studies with n>100 patients show similar findings. Conclusions: NBI appears to outperform 5-ALA and HAL in terms of diagnostic accuracy. All three modalities present high FPR, hence indicating the ability to detect additional cases and lesions beyond WLC.

Diagnostic performance of image technique based transurethral resection for non-muscle invasive bladder cancer: systematic review and diagnostic meta-analysis

OBJECTIVE

To explore the diagnostic performance of image technique based transurethral resection for bladder cancer, with white light-guided cystoscopy (WLC) as the reference standard.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed/MEDLINE, Web of Science, the Cochrane Library, Central Register of Controlled Trials and Embase from inception to 31 March 2018.

METHODS

Included studies reported the diagnostic performance of photodynamic diagnosis (PDD) with 5-aminolevulinic acid (5-ALA), PDD with hexaminolevulinic acid (HAL) or narrow band imaging (NBI), with WLC as the reference standard at the patient or lesion level. The studies' risk of bias (RoB) was assessed using Quality Assessment of Diagnostic Studies-2. Data were pooled using a random effect diagnostic meta-analysis, and subgroup analyses were performed.

RESULTS

Twenty-six studies comprising a total of 3979 patients were included in this diagnostic meta-analysis. Pooled sensitivity (SSY), specificity (SPY), diagnostic OR (DOR) and area under the receiver operating characteristic curve (AUROC) values were calculated per group for NBI, HAL and 5-ALA at the lesion or patient level. NBI showed significant diagnostic superiority compared with WLC at the lesion level (SSY 0.94, 95% CI 0.82 to 0.98; SPY 0.79, 95% CI 0.73 to 0.85; DOR 40.09, 95% CI 20.08 to 80.01; AUROC 0.88, 95% CI 0.85 to 0.91). NBI presented the highest DOR (358.71, 95% CI 44.50 to 2891.71) in the patient level. Subgroup analyses were performed on studies with low to moderate RoB and at least 100 patients at the lesion level. These results were consistent with those of the overall analysis.

CONCLUSIONS

Pooled data indicated that image technique based transurethral resection (NBI, HAL and 5-ALA) showed diagnostic superiority compared with WLC. Moreover, NBI is potentially the most promising diagnostic intervention, showing the best diagnostic performance outcomes. Further prognostic outcomes of novel imaging technologies compared with those WLC should be explored in addition to current diagnostic performance analysis.

A review on the accuracy of bladder cancer detection methods

Background and purpose: Bladder cancer is the most common malignant tumour in the urinary system, with a high incidence and recurrence rate. While the incidence of bladder cancer has been rising in recent years, the prevalence of bladder carcinoma is showing an increasing tendency in the younger age group. There are several methods to detect bladder cancer, but different methods have varying degrees of accuracy which intrinsically depends on the method's sensitivity and specificity. Our aim was to comprehensively summarize the current detection methods for bladder cancer based on the available literature, and at the same time, to find the best combination of different effective methods which can produce a high degree of accuracy in detecting the presence of cancerous cells in the bladder. Materials and Methods: We used key word retrieval method for searching related references in English that had been indexed in PubMed and Medline. Results and Discussion: This paper discussed the different detection methods and their sensitivities/specificities as well as the advantages and disadvantages. We summarized the best identified cancer cell detection methods with higher sensitivity/specificity. Conclusion: The results of this review can positively help to identify accurate methods for detecting bladder cancer and highlight areas to be further improved for future research work.

The Impact of Narrow Band Imaging in the Detection and Resection of Bladder Tumor in Transitional Cell Carcinoma of the Bladder: A Prospective, Blinded, Sequential Intervention Randomized Controlled Trial

OBJECTIVE

To determine the impact of Narrow Band Imaging (NBI) in detection and resection of tumors during transurethral resection of bladder cancer.

MATERIALS AND METHODS

This was a single center randomized prospective interventional study with a sequential intervention design. Patients with bladder tumors were randomized into 2 arms where they were resected under white light (WL) first followed by NBI in arm A, or NBI followed by WL in arm B. The number of patients in whom additional lesions were detected by the second light source, in both arms, was analyzed. The feasibility of initial resection of tumor under NBI was also studied.

RESULTS

A total of 110 patients were randomized. Of 54 patients in arm A (WL first) additional lesions were identified at the second look in 20 patients (37%). In contrast, of 56 patients in arm B (NBI first), additional lesions were identified in 5(9%) patients. This difference of 28% was statistically significant (P value <.001). In arm B (NBI first), there were 7 breaches in protocol, and all these patients had high risk (more than or equal to 3 in number or 3 cm in size) tumors (P value <.002).

CONCLUSION

Narrowband imaging is superior to WL in the detection of tumors, thus allowing a more complete resection. However, initial resection under NBI is difficult due to poor visibility, especially for high-risk tumors.

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

Purpose

The purpose of this study was to evaluate the efficacy of narrow-band imaging (NBI) as a diagnostic tool for detecting bladder tumors during cystoscopy compared with white light cystoscopy (WLC).

Materials and Methods

From December 2013 to June 2017, a randomized prospective study was conducted on 198 patients underwent transurethral resection of bladder tumor by a single surgeon. The patients were divided into two groups according to diagnostic method. In Group I, WLC only was performed. In Group II, NBI was additionally performed after WLC. We analyzed the rate of detection of bladder tumors as a primary endpoint. In addition, we evaluated rates of recurrence in each group.

Results

There were no significant differences between the two groups in characteristics except hypertension. In the analysis of rates of detection, the probability of diagnosing cancer was 80.9% (114/141) in the WLC group, and the probability of diagnosing cancer using WLC in the NBI group was 85.5% (159/186). After switching from WLC to NBI for second-look cystoscopy in the NBI group, NBI was shown to detect additional tumors with a detection rate of 35.1% (13/37) from the perspective of the patients and 42.2% (27/64) from the perspective of the tumors. The 1-year recurrence-free rate was 72.2% in the WLC group and 85.2% in the NBI group (p=0.3).

Conclusions

NBI had benefits for detecting tumors overlooked by WLC. Although the difference in the 1-year recurrence-free rate was not statistically significant, our results showed a trend for higher recurrence in the NBI group.

What Is the Best Lens Angle for Rigid Diagnostic Cystoscopy? A Comparison of 30-Degree and 70-Degree Lenses

The optimal degree of cystoscope to perform diagnostic cystoscopy is dependent on the surgeon's discretion because there are no studies addressing the superiority of one degree of cystoscope over another. The objective was to determine which lens, 70-degree versus 30-degree lens, was better in identifying lesions scattered throughout the bladder.

METHODS

A simulation was created using 3 different artificial bladder models complete with sutures representing lesions placed at different locations in each bladder. Gynecologists and urologists performed cystoscopy using both the 30- and 70-degree lenses on the bladder models in a randomized and single-blinded fashion. The physicians performed routine diagnostic cystoscopy and noted the number of lesions throughout the bladder. The number of lesions each physician identified and the time to complete cystoscopy were noted. A total of 16 physicians participated, and there were a total of 18 lesions among the 3 different bladder models.

RESULTS

A total of 86 cystoscopy trials were obtained from all physicians and bladder models attempted. The odds of detecting a lesion with the 70-degree lens cystoscope was 1.77 times greater than the 30-degree lens cystoscope (95% confidence interval, 1.24-2.53; P = 0.002). There was also difference in the average number of lesions found between the 30- and 70-degree cystoscopes with 2.6 ± 2.7 more lesions identified using the 70-degree cystoscope compared with the 30-degree cystoscope. In terms of specific location, 2.6 ± 1.7 more lesions were found at the bladder neck using the 70-degree lens scope versus the 30-degree lens scope (95% confidence interval, 1.37-3.83; P = 0.013).

CONCLUSIONS

The results suggested that the 70-degree lens was the better choice for the identification of bladder lesions when compared with the 30-degree lens in rigid diagnostic cystoscopy.

Optical improvements in the diagnosis of bladder cancer: implications for clinical practice

Background

For over 100 years white-light cystoscopy has remained the gold-standard technique for the detection of bladder cancer (BCa). Some limitations in the detection of flat lesions (CIS), the differentiation between inflammation and malignancy, the inaccurate determination of the tumor margin status as well as the tumor depth, have led to a variety of technological improvements. The aim of this review is to evaluate the impact of these improvements in the diagnosis of BCa and their effectiveness in clinical practice.

Methods

A systematic literature search was conducted according to the PRISMA statement to identify studies reporting on imaging modalities in the diagnosis of NMIBC between 2000 and 2017. A two-stage selection process was utilized to determine eligible studies. A total of 74 studies were considered for final analysis.

Results

Optical imaging technologies have emerged as an adjunct to white-light cystoscopy and can be classified according to their scope as macroscopic, microscopic and molecular. Macroscopic techniques including photodynamic diagnosis (PDD), narrow-band imaging (NBI) and the Storz Professional Image Enhancement System (IMAGE1 S, formerly known as SPIES) are similar to white-light cystoscopy, but are superior in the detection of bladder tumors by means of contrast enhancement. Especially the detection rate of very mute lesions in the bladder mucosa (CIS) could be significantly increased by the use of these methods. Microscopic imaging techniques like confocal laser endomicroscopy and optical coherence tomography permit a real-time high-resolution assessment of the bladder mucosa at a cellular and sub-cellular level with spatial resolutions similar to histology, enabling the surgeon to perform an 'optical biopsy'. Molecular techniques are based on the combination of optical imaging technologies with fluorescence labeling of cancer-specific molecular agents like antibodies. This labeling is intended to favor an optical distinction between benign and malignant tissue.

Conclusions

Optical improvements of the standard white-light cystoscopy have proven their benefit in the detection of BCa and have found their way into clinical practice. Especially the combination of macroscopic and microscopic techniques may improve diagnostic accuracy. Nevertheless, HAL-PDD guided cystoscopy is the only approach approved for routine use in the diagnosis of BCa by most urological associations in the EU and USA to date.

Narrow band imaging-assisted transurethral resection reduces the recurrence risk of non-muscle invasive bladder cancer: A systematic review and meta-analysis

CONTEXT

Compared with white light imaging (WLI) cystoscopy, narrow band imaging (NBI) cystoscopy could increase the visualization and detection of bladder cancer (BC) at the time of transurethral resection (TUR). NBI cystoscopy could increase the detection of BC, but it remains unclear whether narrow band imaging-assisted transurethral resection (NBI-TUR) could reduce the recurrence risk of non-muscle invasive bladder cancer (NMIBC). Several randomized clinical trials (RCTs) have recently tested the efficacy of NBI-TUR for NMIBC.

OBJECTIVE

To perform a systematic review and meta-analysis of RCTs and evaluate the efficacy of NBI-TUR for NMIBC compared with white light imaging-assisted transurethral resection (WLI-TUR). The end point was recurrence risk.

EVIDENCE ACQUISITION

A systematic review of PubMed, Medline, Ovid, Embase, Cochrane and Web of Science was performed in February 2016 and updated in July 2016.

EVIDENCE SYNTHESIS

Overall, six (n = 1084) of 278 trials were included. Three trials performed narrow band imaging-assisted electro-transurethral resection (NBI-ETUR), and two trials performed narrow band imaging-associated bipolar plasma vaporization (NBI-BPV). The last trial performed narrow band imaging-associated holmium laser resection (NBI-HLR). Statistical analysis was performed using Review Manager software (RevMan v.5.3; The Nordic Cochrane Center, Copenhagen, Denmark). The recurrence risk was compared by calculating risk ratios (RRs) with 95% confidence interval (CIs). Risk ratios with 95% CIs were calculated to compare 3-mo, 1-yr, and 2-yr survival rates. NBI-TUR was associated with improvements in the 3-mo recurrence risk (RR: 0.39; 95% CI, 0.26-0.60; p < 0.0001), 1-yr recurrence risk (RR: 0.52; 95% CI, 0.40-0.67; p < 0.00001) and 2-yr recurrence risk (RR: 0.60; 95% CI, 0.42-0.85; p = 0.004) compared with WLI-TUR.

CONCLUSIONS

Compared with WLI-TUR, NBI-TUR can reduce the recurrence risk of NMIBC. The results of this review will facilitate the appropriate application of NBI in NMIBC.

A meta-analysis of narrow band imaging for the diagnosis and therapeutic outcome of non-muscle invasive bladder cancer

Objectives

To assess the additional detection rate (ADR) of within-patient comparisons of Narrow band imaging (NBI) and white light cystoscopy (WLC) for non-muscle invasive bladder cancer (NMIBC) detection and compare the impact of NBI and WLC on bladder cancer recurrence risk.

Methods

We searched relevant studies from PubMed, Embase, Medline, Web of Science and the Cochrane Library database for all articles in English published beforeJuly26^th, 2016. Pooled ADR, diagnostic accuracy, relative risk (RR) and their 95% confidence intervals (CIs) were calculated.

Results

Twenty-five studies including 17 full texts and eight meeting abstracts were included for analysis. Compared to WLC, pooled ADR of NBI for NMIBC diagnosis was 9.9% (95% CI: 0.05–0.14) and 18.6% (95% CI: 0.15–0.25) in per-patient and per-lesion analysis, respectively. Pooled ADR of NBI for carcinoma in situ (CIS) diagnosis was 25.1% (95% CI: 0.09–0.42) and 31.1% (95% CI: 0.24–0.39) for per-patient and per-lesion analyses, respectively. The pooled sensitivity of NBI was significantly higher than WLC both at the per-patient (95.8% vs. 81.6%) and per-lesion levels (94.8% vs. 72.4%). In addition, NBI significantly reduced the recurrence rate of bladder cancer with a pooled RR value of 0.43 (95% CI: 0.23–0.79) and0.81 (95% CI: 0.69–0.95) at month three and twelve, respectively.

Conclusions

NBI is a valid technique that improves the diagnosis of NMIBC and CIS compared to standard WLC either at per-patient or per-lesion level. It can reduce the recurrence rate of bladder cancer accordingly.

[Narrow band imaging-assisted cystoscopy in bladder tumor follow-up: Can more tumors be identified?]

BACKGROUND

Narrow band imaging (NBI) is a new technique of urethrocystoscopy, in which only certain wavelengths [415 (blue) and 540 nm (green)] are used to detect urothelial carcinoma. The aim of the investigation was to analyze the potential benefit of NBI in the follow-up of patients with transitional cell carcinoma of the bladder.

METHODS

Between August 2013 and July 2014, patients with a history of transitional cell carcinoma of the bladder, presenting for follow-up cystoscopy, were either examined via flexible white light endoscopy (WLE) plus second look WLE (n = 251, controls) or second look NBI cystoscopy alone (n = 251) in the same session.

RESULTS

Rates of recurrences were similar in the two groups [NBI 68 (27.1 %); WLE 70 (27.9 %)]. NBI after WLE identified more tumors in 13 patients (5.69 vs. 3.92). In 8 patients NBI showed no vascularization in suspicious areas. In the control arm, in 8 cases more tumors (3.75 vs. 3.13) were identified in the second WLE.

CONCLUSIONS

The additional use of NBI in the follow-up cystoscopy of patients after transurethral resection of nonmuscle invasive bladder cancer leads to an increased number of detected tumors; however, a part of the additionally detected tumors can be explained by the double examination. NBI appears to provide information in individual cases whether transurethral resection of bladder tumor is necessary.

Comparison of White Light, Photodynamic Diagnosis, and Narrow-band Imaging in Detection of Carcinoma In Situ or Flat Dysplasia at Transurethral Resection of the Bladder: the DaBlaCa-8 Study

OBJECTIVE

To compare findings in NBI to findings in WL and PDD in a high-risk patient population.

MATERIALS AND METHODS

A total of 171 patients were included in the study from 4 different urology departments in Denmark and Norway. Patients were scheduled for a PDD-guided transurethral tumor resection or cystoscopy-guided biopsy in accordance with Danish guidelines, on the suspicion of primary or concomitant CIS. All patients were examined with WL cystoscopy followed by both NBI and PDD before biopsy.

RESULTS

A total of 136 patients were biopsied due to findings with suspicion of CIS in at least 1 modality (482 biopsies with a mean of 3.5 biopsies per patient). Analysis at patient level showed that NBI and PDD had a significantly higher sensitivity regarding identification of CIS and dysplasia compared with WL (NBI: 95.7%, PDD: 95.7% vs WL: 65.2%, P < .05). Specificity was not significantly different between the 3 methods (NBI: 52.0%, PDD: 48.0%, and WL: 56.8%). When analyzed per biopsy, NBI and PDD had a significantly higher sensitivity than WL (NBI: 72.7% and PDD: 78.2% vs WL: 52.7%, P < .05), whereas the positive predictive values were not significantly different (NBI: 23.7%, PDD: 22.2%, and WL: 19.0%).

CONCLUSION

NBI was found to be a valid alternative to PDD regarding diagnosis of CIS and flat dysplasia.

Role of Narrow Band Imaging in Management of Urothelial Carcinoma

Urothelial carcinoma of the bladder and upper tract is primarily diagnosed by white light endoscopy, which has well-known limitations that contribute to the increased risk of tumor recurrence and progression. Narrow band imaging (NBI) is an optical imaging technology that facilitates detection of tumor vasculature and differentiation of benign urothelium from neoplastic tissue. For urothelial carcinoma, NBI may be utilized in a variety of clinical settings, including office cystoscopy for initial identification and surveillance, transurethral resection for pathological diagnosis, and ureteroscopic management of upper tract lesions. Early evidence suggests that NBI increases the detection of urothelial carcinoma in the bladder and upper tract, including flat high-grade lesions such as carcinoma-in-situ that are a diagnostic challenge under white light. NBI also appears to improve the quality of transurethral resection and thereby reduce the frequency of tumor recurrence.

Narrow band imaging and bladder cancer: when and how

Narrow band imaging (NBI) is an optical enhancement technology for endoscopy. NBI works filtering the standard white light in two bandwidths of illumination of 415 nm, blue, and 540 nm, green. As a result, capillaries on mucosal surface appear brown and veins in connective subepithelial layer cyan, enhancing the contrast among epithelial, subepithelial tissue and its vascularisation. Given that it is a filter, it is safe, does not need any kind of instillation and the vision modality can be switched from NBI to white light and vice versa without any limitations of time. NBI-assisted cystoscopy increases the detection rate of urothelial lesions and enhances visibility of tumour margins with respect to standard white light modality, although it does not need a particular learning curve. NBI exploration of the bladder should be avoided during active bleeding because the light absorption would be excessive impeding an optimal vision. Moreover, it should always be employed in combination with standard white light modality to avoid an excess of false-positive findings, particularly during or immediately after topic treatments. It can be used in office to anticipate bladder recurrences and in the operating theatre to perform a complete tumour resection. As a matter of fact, it is able to reduce the recurrence rate and ameliorate bladder cancer management by identifying high-grade cancerous tissue, especially Cis, undetected by the standard white light modality.

A network meta-analysis of therapeutic outcomes after new image technology-assisted transurethral resection for non-muscle invasive bladder cancer: 5-aminolaevulinic acid fluorescence vs hexylaminolevulinate fluorescence vs narrow band imaging

Background

This study included a network meta-analysis of evidence from randomized controlled trials (RCTs) to assess the therapeutic outcome of transurethral resection (TUR) in patients with non-muscle-invasive bladder cancer assisted by photodynamic diagnosis (PDD) employing 5-aminolaevulinic acid (5-ALA) or hexylaminolevulinate (HAL) or by narrow band imaging (NBI).

Methods

Relevant RCTs were identified from electronic databases. The proceedings of relevant congresses were also searched. Fifteen articles based on RCTs were included in the analysis, and the comparisons were made by qualitative and quantitative syntheses using pairwise and network meta-analyses.

Results

Seven of 15 RCTs were at moderate risk of bias for all quality criteria and two studies were classified as having a high risk of bias. The recurrence rate of cancers resected with 5-ALA-based PDD was lower than of those resected using HAL-based PDD (odds ratio (OR) = 0.48, 95 % confidence interval (CI) [0.26–0.95]) but was not significantly different than those resected with NBI (OR = 0.53, 95 % CI [0.26–1.09]). The recurrence rate of cancers resected using HAL-based PDD versus NBI did not significantly differ (OR = 1.11, 95 % CI [0.55–2.1]). All cancers resected using 5-ALA-based PDD, HAL-based PDD, or NBI recurred at a lower rate than those resected using white light cystoscopy (WLC). No difference in progression rate was observed between cancers resected by all methods investigated.

Conclusions

The recurrence rate of some bladder cancers can be decreased by the implementation of either PDD- and NBI-assisted TUR; in real settings, clinicians should consider replacing WLC as the standard imaging technology to guide TUR.

The role of narrow-band imaging in the management of non-muscle-invasive bladder cancer

Narrow-band imaging is a young optical enhancement technology for endoscopy. It is a filter to the standard white light which increases the contrast between underlying vasculature and epithelial strata of the mucosa, improving the detection of bladder cancer with particular regard to high grade, flat lesions. Narrow band imaging is absolutely safe, may be used any time during a procedure, either during office cystosopy or transurethral resection, and implies a minimal burden for the healthcare provider given the absence of a learning curve and the limited cost of the camera and light source. The ameliorated detection translates into an improved management of the disease and a lower recurrence risk in prospective randomized studies, suggesting the inclusion of the technology in daily clinical practice.

Narrow band imaging diagnosis of bladder cancer: systematic review and meta-analysis

What's known on the subject? and What does the study add? In recent years, more attention has focused on the role of narrow band imaging (NBI) in bladder cancer detection and NBI technology has spread rapidly. It is an important method for diagnosing new or recurrent bladder cancer. But its diagnostic accuracy is still uncertain. This paper summarizes the diagnostic accuracy of NBI in bladder cancer and compares NBI with white light imaging. The results show that NBI cystoscopy significantly improves the detection accuracy in bladder cancer, compared with white light imaging. However, some limitations still exist. Multicentre randomized studies are recommended to determine whether the visual advantages of NBI can translate into real therapeutic benefit for individual patients.

OBJECTIVE

• To assess the test performance and clinical effectiveness of narrow band imaging (NBI) cystoscopy compared with white light imaging (WLI) cystoscopy in people suspected of new or recurrent bladder cancer.

METHODS

• Literature on NBI cystoscopy in the diagnosis of bladder cancer was searched in PubMed, EMBASE, Cochrane Library, MEDLINE and CNKI, with hand searching of relevant congress abstracts and journals. • The literature was selected according to inclusion and exclusion criteria. The Meta-DiSc1.4 software was used to review management and analysis.

RESULTS

• Eight studies including 1022 patients assessed test performance. • On a per-person analysis, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio of NBI and WLI were respectively 0.943 (95% CI 0.914-0.964) and 0.848 (95% CI 0.803-0.885), 0.847 (95% CI 0.812-0.878) and 0.870 (95% CI 0.831-0.903), 7.038 (95% CI 3.357-14.754) and 6.938 (95% CI 2.052-23.465), 0.054 (95% CI 0.012-0.237) and 0.181 (95% CI 0.091-0.361), and 185.32 (95% CI 45.714-751.26) and 42.931 (95% CI 8.088-227.88). • The area under the curve and Q* of NBI and WLI were respectively 0.9781 and 0.8944, and 0.9337 and 0.8253. • For the characterization of carcinoma in situ, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio of NBI were 0.927 (95% CI 0.878-0.960), 0.768 (95% CI 0.730-0.802), 4.545 (95% CI 2.820-7.325), 0.125 (95% CI 0.051-0.304) and 48.884 (95% CI 15.642-152.77) on a per-person analysis. • The area under the curve and Q* were 0.9391 and 0.8763.

CONCLUSION

• NBI is an effective method for the identification of abnormal lesions including carcinoma in situ and can provide higher diagnostic precision of bladder cancer than WLI.

New optical imaging technologies for bladder cancer: considerations and perspectives

PURPOSE

Bladder cancer presents as a spectrum of different diatheses. Accurate assessment for individualized treatment depends on initial diagnostic accuracy. Detection relies on white light cystoscopy accuracy and comprehensiveness. Aside from invasiveness and potential risks, white light cystoscopy shortcomings include difficult flat lesion detection, precise tumor delineation to enable complete resection, inflammation and malignancy differentiation, and grade and stage determination. Each shortcoming depends on surgeon ability and experience with the technology available for visualization and resection. Fluorescence cystoscopy/photodynamic diagnosis, narrow band imaging, confocal laser endomicroscopy and optical coherence tomography address the limitations and have in vivo feasibility. They detect suspicious lesions (photodynamic diagnosis and narrow band imaging) and further characterize lesions (optical coherence tomography and confocal laser endomicroscopy). We analyzed the added value of each technology beyond white light cystoscopy and evaluated their maturity to alter the cancer course.

MATERIALS AND METHODS

Detailed PubMed® searches were done using the terms "fluorescence cystoscopy," "photodynamic diagnosis," "narrow band imaging," "optical coherence tomography" and "confocal laser endomicroscopy" with "optical imaging," "bladder cancer" and "urothelial carcinoma." Diagnostic accuracy reports and all prospective studies were selected for analysis. We explored technological principles, preclinical and clinical evidence supporting nonmuscle invasive bladder cancer detection and characterization, and whether improved sensitivity vs specificity translates into improved correlation of diagnostic accuracy with recurrence and progression. Emerging preclinical technologies with potential application were reviewed.

RESULTS

Photodynamic diagnosis and narrow band imaging improve nonmuscle invasive bladder cancer detection, including carcinoma in situ. Photodynamic diagnosis identifies more papillary lesions than white light cystoscopy, enabling more complete resection and fewer residual tumors. Despite improved treatment current data on photodynamic diagnosis do not support improved high risk diathetic detection and characterization or correlation with disease progression. Prospective recurrence data are lacking on narrow band imaging. Confocal laser endomicroscopy and optical coherence tomography potentially grade and stage lesions but data are lacking on diagnostic accuracy. Several emerging preclinical technologies may enhance the diagnostic capability of endoscopic imaging.

CONCLUSIONS

New optical imaging technologies may improve bladder cancer detection and characterization, and transurethral resection quality. While data on photodynamic diagnosis are strongest, the clinical effectiveness of these technologies is not proven. Prospective studies are needed, particularly of narrow band imaging, confocal laser endomicroscopy and optical coherence tomography. As each technology matures and new ones emerge, cost-effectiveness analysis must be addressed in the context of the various bladder cancer types.

[Endourological imaging with narrow band imaging]

Narrow band imaging (NBI) is an optical diagnostic procedure which utilizes the narrowing of the wavelength of visible light in the range between 415 and 550 nm. The NBI is mostly used for the diagnostics of inflammation or tumors of the gastrointestinal tract. The first investigations for diagnostics of bladder cancer using NBI date from 2008. Currently data on resection, follow-up and recurrence behavior of bladder cancer are available. In all publications NBI was tested against white light. A randomized study comparing NBI with photodynamic diagnostics has not yet been carried out. In this article current study results on the application of NBI for bladder cancer will be presented.

Emerging endoscopic and photodynamic techniques for bladder cancer detection and surveillance

This review provides an overview of emerging techniques, namely, photodynamic diagnosis (PDD), narrow band imaging (NBI), Raman spectroscopy, optical coherence tomography, virtual cystoscopy, and endoscopic microscopy for its use in the diagnosis and surveillance of bladder cancer. The technology, clinical evidence and future applications of these approaches are discussed with particular emphasis on PDD and NBI. These approaches show promise to optimise cystoscopy and transurethral resection of bladder tumours.