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 C(16:1), C(18:3), C(18:2), C(18:1), C(20:4), and C(22:6) 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 C(16:1), C(18:3), C(18:2), C(18:1), C(20:4), and C(22:6) in CRC patients were significantly decreased compared with healthy controls and BCD patients. A combination of C(16:1), C(18:2), C(20:4), and C(22:6) 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 C(16:1), C(18:2), C(20:4), and C(22:6 )could be diagnostic indicators of early-stage CRC patients.