We identified a four-biomarker signature based on miR-221, miR-1305, miR-4708, and RMDN2 expression levels that allowed for the subdivision of TNBC into high- or low-risk groups (Hazard Ratio - HR=0.32; 95% Confidence Interval - CI = 0.11-0.91; p=0.03) and are also statistically associated with survival outcome in subgroups of postmenopausal status (HR=0.19; 95%CI = 0.04-0.90; p=0.016), node negative status (HR=0.12; 95%CI = 0.01-1.04; p=0.026), and tumors larger than 2cm (HR=0.21; 95%CI = 0.05-0.81; p=0.021).