Diagnostic accuracy of MicroRNAs as biomarkers for prostate cancer: a systematic review and meta-analysis

Introduction Prostate cancer (PCa) is one of the most common neoplasms in men, and although prostate-specific antigen (PSA) is widely used, it has diagnostic limitations due to its low specificity. In this context, microRNAs (miRNAs) have emerged as potential non-invasive biomarkers. This study aimed to evaluate the diagnostic accuracy of miRNAs miR-21, miR-375, miR-141, and miR-221 for the detection of PCa. Content A systematic review and meta-analysis of diagnostic accuracy studies was performed, following the PRISMA-DTA guidelines. A systematic search was conducted in four electronic databases without language or date restrictions until the search end date. Risk of bias was assessed using the QUADAS-C tool. Bivariate meta-analyses were performed. The certainty of the evidence was assessed using the GRADE approach, with Summary of Findings tables. Summary Fourteen retrospective studies were included. The meta-analyses showed that the miRNAs evaluated generally have high specificity and acceptable sensitivity for the detection of PCa. However, substantial heterogeneity was observed between studies, and there was a high or unclear risk of bias in several domains. Outlook miRNAs miR-21, miR-375, miR-141, and miR-221 show promising potential as diagnostic biomarkers complementary to PSA in PCa. However, the available evidence is limited and of very low certainty, so well-designed and methodologically standardized prospective studies are required before clinical implementation.