Randomized clinical trial of omega-3 fatty acid-supplemented enteral nutrition versus standard enteral nutrition in patients undergoing oesophagogastric cancer surgery

This was a multicenter randomized clinical trial in patients with histologically proven oesophageal or gastric malignancy undergoing subtotal oesophagectomy or total gastrectomy. The omega-3 enriched enteral nutrition group randomized 66 participants and the standard enteral nutrition group randomized 63 participants within a 1:1:1 allocation that also included a control arm. Reported baseline age and sex details were not provided in the source packet.

The active intervention was perioperative omega-3 fatty acid-enriched enteral nutrition given orally/enterally as Oxepa for 7 days before and 7 days after oesophagogastric cancer surgery. The formula provided EPA 0.51 g per 100 ml and DHA 0.22 g per 100 ml, with an energy density of 1.5 kcal/ml and protein 6.25 g per 100 ml; preoperative supplementation targeted 1000 kcal/day, corresponding to 675 ml/day of supplement. It was compared with standard enteral nutrition (Ensure Plus, 1.5 kcal/ml) and a no-preoperative-supplementation control arm.

Omega-3 enriched enteral nutrition increased plasma and lymphocyte omega-3 fatty acid levels, but it did not improve immune function or postoperative clinical outcomes. HLA-DR expression on monocytes was not different between groups (P=0.538) and HLA-DR on activated T lymphocytes was also not different (P=0.204); infective complications, morbidity (P=0.646), mortality (P=1.000), and hospital stay (P=0.701) likewise showed no between-group benefit. Although the omega-6 to omega-3 ratio on the day before surgery was lower in the omega-3 group (1.9:1 vs 4.1:1 vs 4.8:1, P<0.001), the authors concluded that perioperative omega-3 supplementation did not improve clinically relevant outcomes compared with standard enteral nutrition or no preoperative supplementation.

Clinical benefit was not demonstrated despite clear biochemical changes, suggesting limited translation from biomarker effects to outcomes. The intervention was short in duration and the available summary does not provide detailed age, sex, or other baseline characteristics, which limits assessment of generalizability and balance. The trial may also have been underpowered for infrequent clinical endpoints such as mortality and major postoperative complications.