CAPP1 Abstract
Colorectal Adenoma/carcinoma Prevention Programme
In 1993 our consortium launched CAPP1, a European Concerted Action on Polyp Prevention.
Carriers of Familial Adenomatous Polyposis (FAP) were recruited to a randomised placebo controlled trial of 600mg aspirin and/or 30 grams of resistant starch.
Substantial epidemiological evidence supports the view that these interventions might prevent the development of adenomatous polyps, the precursor of colorectal cancer. 206 FAP carriers received treatment. Completed data on 133 subjects followed for at least one year have been analysed. Neither intervention resulted in a significant reduction in polyp number as assessed either by the endoscopist or blinded review of rectal videos. The mean size of largest polyps was, however, significantly reduced in the aspirin only group (p=0.01). A secondary analysis used data from those who had stayed more than one year, suggesting higher compliance. Here, both aspirin alone and the combined aspirin/resistant starch group achieved significance (p=0.04 and p=0.03).
Those treated with starch had significantly shorter crypts (p<0.0001,95% CI 0.87,0.96); those treated with aspirin had longer crypts and a 37% increase in crypt cell proliferation. These data suggest that aspirin and resistant starch are protective against cancer but with different modes of action. Aspirin may act later, preventing progression of small adenomata.
FAP carriers are an ideal study group since their molecular defect is shared
with a majority of sporadic colorectal cancers and any FAP chemoprevention strategy
is likely to have general relevance. Such studies need sustained infrastructure
investment as planned by the new International Society for Gastrointestinal
Hereditary Tumours - InSiGHT.
Information about the CAPP2 project.
