Aim
The accuracy and clinical value of circulating microRNA‐21 (miR‐21) were assessed as a novel diagnostic biomarker of colorectal cancer (CRC).
Method
Medline/PubMed, EMBASE, the Cochrane Library databases and grey literature (Google scholar; British Library) were searched up to 29 September 2014 for eligible studies of the association between blood‐based miR‐21 and a diagnosis of CRC. Quality Assessment of Diagnostic Accuracy Studies (QUADAS) was employed to assess the quality of the included studies by two investigators. Stata12.0 and Meta‐DiSc1.4 software were applied to test the heterogeneity using Cochran's Q test and I2 statistics and to perform the meta‐analysis.
Results
Seven studies with 676 CRC patients and 417 controls were included in the meta‐analysis. All were of high quality (QUADAS scores 12 or 13). For miR‐21, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio to predict CRC were 75% [95% confidence interval (CI) 63–83%], 84% (95% CI 79–87%), 4.61 (95% CI 3.38–6.29), 0.30 (95% CI 0.20–0.46) and 16.89 (95% CI 7.56–37.73) after using a random‐effects model analysis. The area under the summary receiver operating characteristic curve was 0.86 (95% CI 0.83–0.89).
Conclusion
The results suggest that circulating miR‐21 is a biomarker with moderate sensitivity and specificity for CRC.
