Evaluating Urinary Biomarkers for Early Detection of Kidney Damage in Immune Checkpoint Inhibitors-Treated Patients

Immune checkpoint inhibitors (ICIs) have improved cancer treatment; however, their use can be limited by immune-mediated adverse events, such as kidney damage. Diagnostic limitations of nephrotoxicity may lead to worsening of the patient's prognosis. This study aimed to validate a panel of urinary biomarkers as diagnostic tools for kidney damage in patients treated with ICIs.

A prospective study was conducted on patients scheduled to receive ICIs. Those who subsequently developed kidney damage were considered cases; and those who did not were considered controls. A battery of biomarkers was assessed in urine samples at PRE-1, before the first treatment cycle; PRE-3, before the third cycle; and POST-3, 1 week after the third treatment cycle.

A total of 46 patients participated in the study. At PRE-1, increased urinary excretion of IGFBP7, NAG, TIMP-2 × IGFBP7, and transferrin was observed in the case group, suggesting that these markers could be useful for early risk stratification of developing kidney damage. Furthermore, increased urinary excretion of albumin and NGAL was observed at PRE-3, suggesting that these markers could be of diagnostic utility to identify patients that could develop kidney damage once treatment is initiated. All of the aforementioned biomarkers demonstrated significant discriminatory ability between cases and controls, as verified by ROC curve analysis.

The proposed biomarker battery could be used as a preventive tool for decision-making in the management of oncology patients at risk for kidney damage associated with ICIs. Furthermore, its use would allow personalized adjustment of therapy that would minimize the probability of renal complications even before starting the first cycle of treatment.