Diagnostic value of circulating microRNAs as biomarkers for breast cancer: a meta-analysis study

Recent studies have provided new insights into the diagnostic value of circulating microRNAs (miRNAs) for breast cancer (BCa). However, the inconsistent results between studies have prevented the widespread usage of miRNAs in clinics. To systematically assess the potential diagnostic value of circulating miRNAs in BCa, we performed a comprehensive meta-analysis. Eligible studies were retrieved by searching electronic databases. The quality of the studies was assessed on the basis of quality assessment for studies of diagnostic accuracy (QUADAS) criteria. The bivariate meta-analysis model was employed to summarize the diagnostic indices and plot the summary receiver operator characteristic (SROC) curve. A total of 15 studies were included in this meta-analysis, involving 1368 BCa patients and 849 healthy controls. Our bivariate random effects meta-analysis yielded an area under curve (AUC) value of 0.9217, with a sensitivity of 0.82 (95 % confidence interval (CI) 0.80-0.83) and specificity of 0.82 (95% CI 0.80-0.85) for the use of miRNAs in differentiating BCa patients from healthy controls. Notably, our subgroup analysis suggested that a combination of multiple miRNAs (AUC, sensitivity, and specificity of 0.9518, 0.87, and 0.88, respectively) seemed to harbor higher accuracy than single miRNA-based assays (AUC, sensitivity, and specificity of 0.8923, 0.79, and 0.77, respectively). Altogether, our data indicate that circulating miRNA profiling has a potential to be used as a screening test for BCa, among which, the detection of a combined multiple miRNAs may be a more comprehensive indicator than individual miRNA.