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.