Effect of n-3 polyunsaturated fatty acids on Barrett's epithelium in the human lower esophagus.

Randomized study in adults with Barrett's esophagus undergoing routine surveillance endoscopy at a single UK hospital. Participants in the active arm received EPA for 6 months, with paired Barrett's tissue biopsies collected before and after treatment to assess mucosal fatty acids and inflammatory/proliferative biomarkers.

Oral eicosapentaenoic acid (EPA) supplementation at 1.5 g/day, provided as unesterified 99% EPA in 500-mg capsules taken 1 capsule 3 times daily for 6 months. The active regimen was compared with no supplementation.

EPA supplementation increased n-3 fatty acid content in Barrett's tissue and reduced COX-2 protein concentrations, supporting a potential chemopreventive mechanism. The EPA group showed marked increases in tissue 20:5 (from 0.8 to 2.4 vs 0.7 to 0.7 in controls; P2 0.000001 4) and 22:5 (from 0.8 to 1.5 vs 0.6 to 0.8; P2 0.005 4), with an inverse relationship between EPA levels and COX-2 protein. There were no significant changes in COX-2 RNA, PGE2, LTB4, or Ki-67 proliferation.

The trial was small and single-center, with limited completed/analyzed participants in the active arm and a 6-month follow-up. Outcomes were biomarker-based rather than clinical, and there was no significant effect on proliferation or several downstream inflammatory mediators, limiting inference about cancer prevention.