Comparison of diagnostic efficacy between AFI, NBI, and AFI combined with NBI for colonic cancers: A meta-analysis

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.

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.

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).

The combination of AFI and NBI was associated with increased diagnostic value for colonic cancers compared with AFI and NBI alone.