Background: Circular RNAs (circRNAs), which are expressed aberrantly in tissues and body fluids in individuals with hepatocellular carcinoma (HCC), may serve as promising biomarkers for diagnosis of HCC. We performed a meta-analysis of the overall diagnostic performance of circRNAs for diagnosis of HCC.
Methods: PubMed, Web of Science, EMBASE, and Chinese National Knowledge Infrastructure (CNKI) were searched for eligible studies. The quality of all included literature was evaluated using the Quality Assessment for Studies of Diagnostic Accuracy 2 (QUADAS-2) checklist. Statistical analyses were conducted using STATA 12.0 and Meta-Disc 1.4 software.
Results: A total of 6 studies, 2 of which identified up-regulated circRNAs and 4 of which identified down-regulated circRNAs, were included in the meta-analysis. The pooled sensitivity, specificity, and area under the curve (AUC) were 0.75 (95% confidence interval (CI): 0.71 - 0.78), 0.82 (95% CI: 0.78 - 0.85), and 0.90, respectively. Stratified analyses showed that the diagnostic efficacy of down-regulated circRNAs for diagnosis of HCC was inferior to that of up-regulated circRNAs (sensitivity: 0.69 vs. 0.91; specificity: 0.78 vs. 0.94; diagnostic odds ratio (DOR): 9.12 vs. 128.97; AUC: 0.83 vs. 0.99).
Conclusions: Abnormally expressed circRNAs may be diagnostic indicators of HCC. Additional studies are needed to confirm whether circRNAs are diagnostic biomarkers of HCC.