Plasma fatty acids depletion: A metabolic signature related to colon cancer.

Patients with colon cancer (CC) have decreased plasma fatty acid (FA) content, yet few studies have undertaken a systemic approach to understand this phenomenon. Patients with CC (n = 172) and healthy controls (n = 17) were recruited for this study at the University Hospital Son Espases (Spain). Clinical data was obtained from medical records. Plasma FA profile was analysed by gas chromatography-mass spectrometry. Body composition and hepatic steatosis were analysed using computerised tomography. Tumour tissue underwent transcriptomic analysis for consensus molecular subtype (CMS) stratification. Patients with CC (median age 73 years, 46.5% women) had significantly decreased total plasma FA content versus controls (median age 58 years, 41.2% women) (1510.0 nmol/mL vs. 4194.6 nmol/mL median values respectively, p < 0.001). This reduction (≥50%) was consistent across all species, independently of sex, age, body composition or cancer stage. An elevated unsaturated-to-saturated FA ratio was observed in CMS2 tumours (p = 0.01). Plasma inflammatory markers (C-reactive protein and fibrinogen) were above normal range in patients in a stage-dependent manner (p < 0.01). Hepatic enzymes fell within normal range, yet increased with tumour stage. This study indicates that plasma FA content reduction is an intrinsic metabolic alteration of CC already occurring in early stages. Further research will aid clinical significance.