Defining reliable biomarkers is still a challenge in patients with urological tumors. Because miRNAs regulate diverse important cellular processes, these noncoding RNAs are putative molecular candidates. This review intends to give a critical overview about the current state of miRNAs as biomarkers in urological cancers with respect to prognostic stratification as well as for individual treatment selection.

A comprehensive review of the published literature was conducted focusing at the clinical relevance of miRNAs in tissues and body fluids of prostate, bladder and kidney cancer. Using electronic database, 91 articles, published between 2009 and 2015, were selected and discussed regarding the robustness of miRNAs as valid biomarkers.

A number of miRNAs have been identified with prognostic and predictive relevance in different urologic tumor types. However, the inconsistency of the published results and the lack of multivariate testing in independent cohorts do not allow an introduction into clinical decision making at present.

miRNA-based biomarkers are a promising tool for future personalized risk stratification and response prediction in urological cancers.