Diagnostic and prognostic value of miRNAs on salivary gland tumors: a systematic review and meta-analysis.

PURPOSE: Different levels of miRNA expression have been described in salivary gland tumors as a potential diagnostic marker and predictor of survival. We systematically reviewed the literature to assess the diagnostic and prognostic value of miRNAs on salivary gland tumors. METHODS: An electronic search was conducted in PubMed, Scopus, Embase, Cochrane, and Web of Science databases. In the meta-analysis, we assumed random-effects model with adjusted hazard ratio (HR) and 95% confidence intervals (95% CI). For prognostic studies, the risk of bias was assessed by Meta-Analysis of Statistics Assessment and Review Instrument (MAStARI) and Quality Assessment Tool for Diagnostic Accuracy Studies-2 (QUADAS-2) was utilized for diagnostic studies. RESULTS: Gathered data from 1.131 patients in seven studies demonstrated that different levels of miRNA expression presented diagnostic and prognostic in SGTs. The meta-analysis showed that altered miRNA expression were associated with shortened survival (HR, 2.35, 95% CI, 1.77-3.10, P < .00001). For diagnostic meta-analysis, the overall pooled results for specificity and sensibility were 0.87-0.97 (95% CI, 0.72-1) and 0.68-0.91 (95% CI, 0.51-0.96), respectively. CONCLUSION: MicroRNAs may be useful in prognostication of patients with SGTs; however, the diagnostic value of miRNAs in SGTs is still limited.