Endoscopic identification and quantification of aberrant crypt foci in the human colon.

Background: Aberrant crypt foci may be precancerous lesions in the human colon. The occurrence of aberrant crypt foci was compared in patients with an endoscopically normal colon, known adenomatous polyps, and known colorectal cancer.

Methods: In 90 patients (30 colonoscopically normal, 30 with adenomatous polyps, 30 with colorectal cancers) magnification chromoscopy was performed to identify aberrant crypt foci in the distal 10 cm of the rectum. Representative biopsy specimens were obtained for histopathologic assessment.

Results: Aberrant crypt foci were readily identified. Median and (mean) numbers of aberrant crypt foci were as follows: endoscopically normal colon, 3.5 (5.0); adenomatous polyp(s), 4.0 (6.9); and colorectal cancer, 7.5 (9.9). The number of aberrant crypt foci detected was significantly associated (p = 0.02) with an increased odds that a patient would be in the group with known colorectal cancer (odds ratio = 1.11; 95% CI [1.02, 1.21]), but not in any other group.

Conclusions: Despite a stepwise increase in the number of aberrant crypt foci across the 3 groups, aberrant crypt foci was significantly associated only with comorbid colorectal cancer. Aberrant crypt foci was not associated with adenomatous polyp(s) or normal colon. Additional studies are needed to further elucidate the role of aberrant crypt foci in the development of colorectal neoplasia in humans.