NBI Is Clinically Proven to Diagnose More Bladder Cancer

The objective was to evaluate the diagnostic accuracy of cystoscopy assisted by narrow-band imaging compared with white-light imaging for nonmuscleinvasive
bladder cancer.

An electronic database search of PubMed, Embase, the Cochrane Library, Ovid and Web of Science was carried out for all articles comparing narrow-band imaging with white-light imaging cystoscopy in the detection of non-muscle-invasive bladder cancer. The review process followed the guidelines of the Cochrane Collaboration.

Seven studies with prospectively collected data including a total of 1040 patients were identified, and 611 patients with 1476 tumours were detected by biopsy.
In the patient- and tumour-level analysis, an additional 17 % of patients (95 % confidence interval, 10–25 %)and an additional 24 % of tumours (95 % confidence
interval, 17–31 %) were detected by narrow-band imaging, respectively. In the patient- and tumour-level analysis, significantly higher detection rates using narrow-band imaging (rate difference 11 %; 95 % confidence interval 5–17 %; P < 0.001; and rate difference 19 %; 95 % confidence interval 12–26 %; P < 0.001, respectively) rather than white-light imaging were found. On the tumour level, an additional 28 % of carcinoma in situ was detected (95 % confidence interval 14–45 %) by narrow-band imaging, and a significantly higher detection rate (rate difference 11 %; 95 % confidence interval 1–21 %; P = 0.03) was found. The false-positive detection rate of tumour level did not differ significantly between the two techniques.

Cystoscopy assisted by narrow-band imaging detects more patients and tumors of non-muscle-invasive bladder cancer than white-light imaging, and it might be an additional or alternative diagnostic technique for nonmuscle- invasive bladder cancer.

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.

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.

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

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 bycalculating risk ratios (RRs) with 95% confidenceinterval (CIs). Risk ratios with 95% CIs were calculatedto compare 3-mo, 1-yr, and 2-yr survival rates.NBI-TUR was associated with improvements in the3-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 withWLI-TUR.

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.

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).

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.

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.

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.

NBI was found to be a valid alternative to PDD regarding diagnosis of CIS and flat dysplasia10.

A prospective, nonrandomized, international multicenter study from Scandinavia analyzed the within-patient comparison of WLI, NBI, and PDD in the detection of CIS or flat dysplasia in a TURB setting.

To characterize the appearance of normal and malignant upper urinary tract lesion appearance under narrow-band imaging (NBI) using the new URF-V digital flexible ureteroscope (DFU), and to determine if NBI, when used in conjunction with white light (WL), could improve detection of malignancy.

NBI and WL were performed in 27 patients at our university teaching hospital, 14 with known cases of upper urinary tract transitional-cell carcinoma (UUT-TCC) as follow-up (group A), and 13 patients with first-suspicion of cancer (group B). Full renal collecting system examination was performed first under WL and then under NBI by a single urologist. Biopsies were taken from all detected lesions using the
biopsy forceps and sent for examination by a pathologist who was blinded to the gross description of the lesion. Pathology interpretations were then compared with the corresponding WL and NBI images. Holmium laser vaporization was performed for all apparent lesions.

Subjectively, NBI significantly improved the endoscopic visualization of the tumors, providing a detailed description of their limits and vascular architecture. Objectively, five additional tumors (14.2%) in four patients, as well the extended limits of three tumors (8.5%) in three patients were detected by NBI when findings by WL imaging were considered normal.

This is one of the first reports regarding NBI for UUT-TCC. From this study, we recommend this technology as a valuable diagnostic method, because it considerably improves tumor detection rate by 22.7% compared with WL.

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