The natural history of aberrant crypt foci

Background

Aberrant crypt foci (ACF) are the putative precursors to colorectal adenomas and may be useful as biomarkers. Knowledge of their natural history is essential to understanding their potential utility.

Objective

Our purpose was to examine ACF detection 1 year after initial observation.

Design

We conducted a multicenter study of ACF by using a standardized protocol. ACF in the rectum were assessed and subjects returned 1 year later to evaluate the natural history of the lesions.

Setting

Ancillary study to the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.

Results

Of 78 subjects enrolled, 64 (82%) returned for a repeat examination 1 year later. The mean age was 71 years, 70% were male, and 54% had a history of adenomatous polyps. At the initial examination, 66% of subjects had at least 1 ACF detected in the rectum, with a mean of 2.1 ± 2.3 per person. One year later, 60% of these subjects had at least 1 of the original ACF reidentified, but only 43% of all ACF were reidentified. A total of 56% of subjects had new ACF identified.

Limitations

These results are generated from the pilot phase. Improvements or change in technique over time could have influenced the results.

Conclusions

A total of 60% of subjects who had ACF continued to have at least one ACF 1 year later, but less than half the specific ACF could be reidentified, and more than 50% of subjects had new ACF. These results imply a considerable dynamic to ACF detection over a 1-year period of observation.

Abbreviations: ACF, aberrant crypt foci, FSG, flexible sigmoidoscopy, PLCO, Prostate, Lung, Colorectal, and Ovarian cancer screening trial