Survival analyses in the Discovery and Validation Cohorts. (a) miRNAs that were associated with OS and/or PFS in the Discovery Cohort (n = 83), and Validation Cohort (n = 112). Six miRNAs (miR-28-5p, miR-324-5p, miR-214-5p, miR-339-3p, miR-5586-5p, NOVELM00203M) were found to be associated with OS and PFS, independently of COO and IPI, in both the Discovery and Validation Cohorts. Light Blue: miRNA associated with OS; Dark Blue: miRNA associated with OS independently of COO and IPI; Light Green: miRNA associated with PFS; Dark Green: miRNA associated with PFS independently of COO and IPI; miR-5586-5p Kaplan-Meier curves and scatter plots of expression in (ABC)-DLBCL, (GCB)-DLBCL, and (U)nclassified-DLBCL: (b) Discovery Cohort OS, (c) Discovery Cohort PFS, (d) Validation Cohort OS, (e) Validation Cohort PFS. Plots for the other five validated miRNAs are shown in Additional file 9: Figure S7.