Fecal Fatty Acid Profiling as a Potential New Screening Biomarker in Patients with Colorectal Cancer

The fatty acid profile of the fecal metabolome and its association with colorectal cancer (CRC) has not been fully evaluated. We aimed to compare the fecal fatty acid profiles of CRC patients and healthy controls. We enrolled 26 newly diagnosed CRC patients and 28 healthy individuals between July 2014 and August 2014 from our institute. Long- and short-chain fatty acids were extracted from fecal samples and analyzed using gas chromatography-mass spectrometry. Regarding fecal long-chain fatty acids, the levels of total omega-6 polyunsaturated fatty acids and, particularly, of linoleic acid (C18:2 omega-6) were significantly higher in male CRC patients than in healthy men (2.750 +/- 2.583 vs. 1.254 +/- 0.966 A mu g/mg feces, P = 0.040; 2.670 +/- 2.507 vs. 1.226 +/- 0.940 A mu g/mg feces, P = 0.034, respectively). In addition, the levels of total monounsaturated fatty acid and, particularly, of oleic acid (C18:1 omega-9) were significantly higher in male CRC patients than in healthy men (1.802 +/- 1.331 vs. 0.977 +/- 0.625 A mu g/mg feces, P = 0.027; 1.749 +/- 1.320 vs. 0.932 +/- 0.626 A mu g/mg feces, P = 0.011, respectively). However, those differences were not shown in female gender. The level of fecal short-chain fatty acids was not different between CRC patients and healthy controls. There were changes in the profiles of fecal fatty acid metabolomes in CRC patients compared to healthy controls, implying that fecal fatty acids could be used as a novel screening tool for CRC.