KIM-1 (kidney injury molecule 1) in the urine of renal cell carcinoma patients

Abstract

Objective: to assess the potential clinical significance of KIM-1 (kidney injury molecule 1) as a urinological marker for kidney cancer.Materials and methods. An enzyme-linked immunosorbent assay was used to assess urinary KIM-1 (uKIM-1 — kidney injury molecule 1) levels in 67 patients with renal cell carcinoma (RCC) and 36 healthy volunteers (a control group).Results. Both in patients and in healthy individuals, uKIM-1 levels were age independent. A difference between mean uKIM-1 values in RCC patients (2.4 ± 0.2 ng/ml) and the control group (0.7 ± 0.1 ng/ml) was statistically significant (p <0.0001). In RCC patients the higher uKIM-1 level was observed at more advanced clinical disease stages: the values increasedfrom 2.0 ± 0.2 ng/ml at the stage I and 3.0 ± 0.5 ng/ml at the stage II—III to 4.4 ± 1.2 ng/ml at the stage IV. In the group of patients with stage IRCC, most representative by the number of cases (n = 44) the uKIM-1 levels correlated with the tumor size and were increased in patients with different histological subtypes of the tumor, including clear cell, papillary and chromophobe RCC. After nephrectomy, a monotonous decrease in uKIM-1 level was observed, and after 6 days its values approached the mean value in the control group. Two days after kidney resection, uKIM-1 increased and then decreased, remaining elevated after 6 days.Conclusion. This study demonstrates that uKIM-1 can be attributed to potentially significant urine tumor-associated markers of RCC.