Urinary Lipid Profiling for Biomarker Discovery in Clear Cell Renal Cell Carcinoma

BACKGROUND/AIM: Although the prognosis of renal cell carcinoma (RCC) remains poor, early detection and treatment significantly contribute to better outcomes. However, reliable tumor biomarkers for RCC have not yet been established. We herein compared urinary lipid profiles between patients with clear cell RCC (ccRCC) and healthy controls to identify potential diagnostic biomarkers. PATIENTS AND METHODS: Urine samples were collected from 52 patients who underwent radical or partial nephrectomy and were pathologically diagnosed with ccRCC and 30 healthy volunteers. Lipid profiling was performed using LC-MS/MS, and 48 lipid species were identified, of which 23 were included in the analysis. RESULTS: Total urinary lipid levels were significantly higher in the ccRCC group than in healthy controls. Among these, acylcarnitines (AcCa), free fatty acids, ceramides, phosphatidylcholines and coenzyme Q were significantly elevated in patients with ccRCC. AcCa showed the highest diagnostic performance, with an area under the receiver operating characteristic curve of 0.804, sensitivity of 80.8%, and specificity of 76.7%. AcCa levels were previously shown to be higher in tumor tissue and blood samples from RCC patients than in healthy controls. CONCLUSION: The present results suggest the potential of AcCa as a non-invasive urinary biomarker for the detection of ccRCC.