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

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of Systematic Reviews, MEDLINE, Embase, several clinical trial registries, and grey literature for published and unpublished studies, irrespective of language.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.

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.

A glance at imaging bladder cancer

Purpose

Early and accurate diagnosis of Bladder cancer (BCa) will contribute extensively to the management of the disease. The purpose of this review was to briefly describe the conventional imaging methods and other novel imaging modalities used for early detection of BCa and outline their pros and cons.

Methods

Literature search was performed on Pubmed, PMC, and Google scholar for the period of January 2014 to February 2018 and using such words as "bladder cancer, bladder tumor, bladder cancer detection, diagnosis and imaging".

Results

A total of 81 published papers were retrieved and are included in the review. For patients with hematuria and suspected of BCa, cystoscopy and CT are most commonly recommended. Ultrasonography, MRI, PET/CT using ¹⁸F-FDG or ¹¹C-choline and recently PET/MRI using ¹⁸F-FDG also play a prominent role in detection of BCa.

Conclusion

For initial diagnosis of BCa, cystoscopy is generally performed. However, cystoscopy can not accurately detect carcinoma insitu (CIS) and can not distinguish benign masses from malignant lesions. CT is used in two modes, CT and computed tomographic urography (CTU), both for dignosis and staging of BCa. However, they cannot differentiate T1 and T2 BCa. MRI is performed to diagnose invasive BCa and can differentiate muscle invasive bladder carcinoma (MIBC) from non-muscle invasive bladder carcinoma (NMIBC). However, CT and MRI have low sensitivity for nodal staging. For nodal staging PET/CT is preferred. PET/MRI provides better differentiation of normal and pathologic structures as compared with PET/CT. Nonetheless none of the approaches can address all issues related for the management of BCa. Novel imaging methods that target specific biomarkers, image BCa early and accurately, and stage the disease are warranted.

Anticipatory Positive Urine Tests for Bladder Cancer

PURPOSE

The aim of this study was to establish the criteria defining an anticipatory positive test for bladder cancer.

METHODS

We reviewed all patients at our institution who underwent urine cytology or UroVysion fluorescence in situ hybridization (FISH) and cystoscopy from 2003 to 2012. Test performance and cancer anticipation was assessed using generalized linear mixed models, mixed-effects proportional hazards models, and cumulative incidence curves using tests performed within 30 days of each other as well as within a lag time of 1 year.

RESULTS

Overall, 6729 urine tests (4729 cytology and 2040 UroVysion FISH) were paired with gold-standard cystoscopies. Sensitivity and specificity were 63 and 41% for cytology, and 37 and 84% for UroVysion FISH, respectively. A 1-year lag time allowed for cancer anticipation and neither test improved. Among patients with positive cytology and initially negative cystoscopy, the hazard ratio of developing a bladder tumor at 1 year was 1.83; 76% of these patients developed a tumor within 1 year. Similarly, among patients with a positive FISH and initially negative cystoscopy, the hazard ratio of developing a bladder tumor at 1 year was 1.56; 40% of these patients developed a tumor within 1 year.

CONCLUSIONS

Urine-based tests for bladder cancer are frequently falsely positive. With further follow-up time, some of these false positive tests are vindicated as true (anticipatory) positive tests, although many will remain false positives. We developed statistical criteria to determine if a test anticipates future cancers or not.