Traeger L, et al. - In this retrospective study, researchers investigated whether serum hepcidin and serum growth/differentiation factor 15 (GDF-15) could serve as biomarkers that correlate with patient’s survival in upper urinary tract urothelial carcinomas (UUTUC) and in renal cell carcinoma (RCC). Participants were 38 patients suffering from UUTUC, 94 patients suffering from RCC, and 21 patients without infections or cancer, all hospitalized at the University Hospital Muenster. Serum hepcidin and GDF-15 levels and their correlations to aggressiveness and progression of the disease and patient’s outcome was determined. Compared to controls, increased serum hepcidin levels as well as serum GDF-15 levels were detected in patients with UUTUC and those with RCC; metastases and cancer relapse were also related to high serum hepcidin and GDF-15 levels. Also, increased serum hepcidin and GDF-15 levels were linked with decreased overall survival in both entities. Overall, high serum hepcidin and GDF-15 levels were correlated to aggressiveness and progression of the disease. Potential prognostic properties of serum hepcidin and GDF-15 levels were also supported.