Urinary Human Kidney Injury Molecule-1 (hKIM-1) Is Not Increased in Patients with Renal Cell Carcinoma.

PURPOSE Human Kidney Injury Molecule-1 (hKIM-1) was proposed as urinary biomarker of renal cell carcinoma (RCC). The aim of the study was to validate urinary hKIM-1 as a biomarker of RCC. MATERIAL AND METHODS Forty-six participants were enrolled into the study, including 30 patients with clear-cell or papillary RCC and 16 matched patients in the comparison group. Preoperative urinary hKIM-1 levels were measured using commercially available ELISA kit and normalized to urinary creatinine levels. RESULTS The concentrations of urinary hKIM-1 normalized to urinary creatinine in patients with RCC and comparison group did not differ significantly (1.35 vs. 1.32 ng/mg creatinine, p=.25). There was also no difference in urinary hKIM-1 concentration regarding stage or grade of renal cancer. Additional analysis of patients without chronic kidney disease (defined as eGFR ≥60mL/min/1.73m²) also did not reveal significant difference in urinary hKIM-1 concentrations between the groups (1.54 vs. 1.37; p=.47). CONCLUSION Results of our study do not confirm recent suggestions that urinary hKIM-1 may be a biomarker of RCC.