Serum Unsaturated Free Fatty Acids: A Potential Biomarker Panel for Early-Stage Detection of Colorectal Cancer

BACKGROUND To screen biomarkers to differentiate early-stage colorectal cancer (CRC) from benign colorectal disease (BCD) and healthy controls. MATERIALS & METHODS Quantitative and qualitative analysis of C16:1, C18:3, C18:2, C18:1, C20:4, and C22:6 in 185 healthy controls, 55 patients with BCD, and 139 patients with CRC was performed. Comparisons of their levels in between CRC patients, BCD patients, and healthy controls were performed using Mann-Whitney U test. RESULTS Serum levels of C16:1, C18:3, C18:2, C18:1, C20:4, and C22:6 in CRC patients were significantly decreased compared with healthy controls and BCD patients. A combination of C16:1, C18:2, C20:4, and C22:6 has excellent diagnostic performance to differentiate early-stage CRC patients from healthy controls plus BCD patients, with an AUC of 0.926, a sensitivity of 84.6%, and a specificity of 89.8%. CONCLUSIONS Serum levels of C16:1, C18:2, C20:4, and C22:6 could be diagnostic indicators of early-stage CRC patients.