ABERRANT CRYPT FOCI OF THE COLON AS PRECURSORS OF ADENOMA AND CANCER

Background Aberrant crypt foci of the colon are possible precursors of adenoma and cancer, but these lesions have been studied mainly in sur gical specimens from patients who already had colon cancer. Methods Us ing magnifying endoscopy, we studied the prevalence, number, size, and dysplastic features of aberrant crypt foci and their distribution acc ording to age in 171 normal subjects, 131 patients with adenoma, and 4 8 patients with colorectal cancer. We also prospectively examined the prevalence of aberrant crypt foci in 11 subjects (4 normal subjects, 6 with adenoma, and 1 with cancer) before and after the administration of 100 mg of sulindac three times a day for 8 to 12 months and compare d the results with those in 9 untreated subjects (4 normal subjects an d 5 with adenoma). All 20 subjects had aberrant crypt foci at base lin e. Results We identified 3155 aberrant crypt foci, 161 of which were d ysplastic; the prevalence and number increased with age. There were si gnificant (P<0.001) correlations between the number of aberrant crypt foci, the presence of dysplastic foci, the size of the foci, and the n umber of adenomas. After sulindac therapy, the number of foci decrease d, disappearing in 7 of 11 subjects. In the untreated control group, t he number of foci was unchanged in eight subjects and slightly increas ed in one (P<0.001 for the difference between the groups). Conclusions Aberrant crypt foci, particularly those that are large and have dyspl astic features, may be precursors of adenoma and cancer. (N Engl J Med 1998;339:1277-84.) (C)1998, Massachusetts Medical Society.