The 2 × 2 factorial seAFOod trial demonstrated that aspirin and omega-3 polyunsaturated fatty acid eicosapentaenoic acid reduce colorectal polyp number (a biomarker of colorectal cancer risk) during colonoscopy surveillance in the Bowel Cancer Screening Programme. The lack of a risk and/or therapeutic response biomarker limits a precision medicine approach to maximise efficacy of these chemoprevention agents. The seAFOod trial collected a comprehensive biobank of blood, urine and tissue samples.
