Comparison of Diagnostic Efficacy Between AFI, NBI, and AFI Combined with NBI for Colonic Cancers: A Meta-Analysis

Background/Aims: Advanced endoscopic imaging technologies have been used for the early detection and differentiation of colonic cancers recently. We aim to evaluate the diagnostic efficacy of autofluorescence imaging (AFI), narrow-band imaging (NBI), and AFI combined with NBI for colonic cancers. Materials and Methods: We searched Medline/PubMed, Embase, Web of Science, and Cochrane Library databases for relevant articles. A random-effects model was used to assess diagnostic efficacy. Heterogeneity was tested by the I2 statistic and Chi-square test. Meta-regression was used to analyze the sources of heterogeneity. Results: The pooled sensitivities for AFI, NBI, and AFI plus NBI were 0.84 (95% confidence interval (CI) 0.82–0.87), 0.84 (95% CI 0.81–0.86), and 0.93 (95% CI 0.90–0.95), respectively. The pooled specificities were 0.44 (95% CI 0.40–0.48), 0.69 (95% CI 0.65–0.72), and 0.69 (95% CI 0.64–0.74), respectively. The sensitivity estimate was significantly higher for AFI plus NBI than AFI or NBI alone (P = 0.041), and the specificity estimates were significantly higher for NBI and AFI plus NBI than AFI (P = 0.031).The pooled diagnostic odds ratio for AFI, NBI, and AFI plus NBI were 8.71 (95% CI 2.90–26.16), 16.02 (95% CI 7.05–36.39), and 57.55 (95% CI 9.82–337.33), respectively. Furthermore, the summary receiver operating characteristic curve area under the curve for AFI, NBI, and AFI plus NBI were 0.8125 with Q* =0.7469, 0.8696 with Q* =0.8001, and 0.9447 with Q* =0.8835, respectively. The Q* index for AFI plus NBI was significantly higher than AFI or NBI alone (P = 0.048). Conclusion: The combination of AFI and NBI was associated with increased diagnostic value for colonic cancers compared with AFI and NBI alone.