The diagnostic and prognostic values of microRNA-21 in patients with gastric cancer: a meta-analysis.

Previous studies demonstrated the pivotal role of miR-21 in the pathogenesis and progression of gastric cancer. This meta-analysis was designed to confirm the diagnostic and prognostic value of microRNA-21 (miR-21) in gastric cancer and to investigate the influence of samples on the results of miR-21 detection.A literature search was conducted in PubMed and Embase databases up to August 2016. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver-operating characteristic (AUC) were calculated by Meta-Disc (version 14.0) or RevMan 5.3 software.Ten studies including 516 patients with gastric cancer and 239 healthy controls were selected. Pooled sensitivity (0.74, 95% CI: 0.69-0.79), specificity (0.81, 95% CI: 0.76-0.86), PLR (3.85, 95% CI: 3.00-4.94), NLR (0.22, 95% CI: 0.31-0.45), and DOR (13.07, 95% CI: 8.81-19.39) as well as AUC (0.8561 ± 0.0204) indicated the good diagnostic accuracy of miR-21 in detecting gastric cancer. The prognostic value of miR-21 for lymph node metastasis in gastric cancer was also demonstrated by the pooled sensitivity (0.56, 95% CI: 0.48-0.64), specificity (0.62, 95% CI: 0.53-0.71), PLR (2.02, 95% CI: 0.90-4.54), NLR (0.58, 95% CI: 0.45-0.75), and DOR (3.50, 95% CI: 1.04-11.83) as well as AUC (0.6673 ± 0.0469). Subgroup analyses showed that the samples used to detect miR-21 were the source of heterogeneity could affect the diagnostic or prognostic value of miR-21 in gastric cancer.miR-21 can be used for the diagnosis of gastric cancer and prognosis of lymph node metastasis in gastric cancer.