Chemopreventive effect of eicosapentaenoic acid (EPA) for colorectal cancer

Background: New preventive strategies are needed to lower the burden of colorectal cancer (CRC). Eicosapentaenoic acid (EPA) has recently been suggested to have a suppressive effect on tumorigenesis and cancer cell growth. Aberrant crypt foci (ACF), are considered as a reliable surrogate biomarker of CRC. We conducted a clinical trial as a preliminary study for CRC chemoprevention to evaluate chemopreventive effect of EPA against colorectal ACF formation.
Methods: This study is a double-blind, placebo-controlled, RCT to be conducted in patients with colorectal ACF and colorectal adenoma/cancer scheduled for polypectomy. Thirty eligible patients were recruited for the study and number of ACF in rectum counted at baseline colonoscopy. Then, participants were allocated randomly to two groups, the EPA group (received oral 900 mg EPA capsules thrice daily) and the placebo group (received oral placebo capsules thrice daily). After one month's treatment with EPA/placebo, colonoscopic examination were performed to evaluate formation of ACF.
Results: At polypectomy, the EPA group had a significant decrease in number of ACF. The proliferation index was significantly decreased and the apoptotic cell index was significantly increased in both normal rectal epithelium and adenomas in EPA group.
Discussion: This is the first study proposed to explore the chemoprevention effect of EPA against colorectal ACF formation in humans. For the future, we plan to conduct a long-term chemoprevention trial of EPA for colorectal adenoma/cancer.