Rajaee A, Sadr-Eshkevari P, McMasters KM, et al. - Researchers aimed to determine risk factors that can predict the risk of nonsentinel node metastases (NSNM) in this systematic review and meta-analysis. Searching Medline, Web of Science, Embase, and Cochrane, 50 publications discussing predictive factors for NSNM were identified as suitable for additional analysis. The following clinical and primary tumor factors were consistently recognized as risk factors for NSNMs: age > 50, T stage 3 or 4, Clark level IV/V, ulceration, microsatellitosis, lymphovascular invasion, nodular histology, and extremity vs trunk primary tumor location. In addition, the following SLN factors were identified to be predictive of NSNMs: > 1 positive SLN, SLN micrometastatic tumor burden, diameter > 2 mm, extracapsular extension, nonsubcapsular location (Dewar), and Rotterdam > 1 mm or ≥ 0.1 mm. Overall findings support that various clinical and pathologic risk factors can be employed to prognosticate the risk of NSNMs and that they can be assessed with SLN biopsy alone.