NEW YORK (Reuters Health) – Although high-definition chromocolonoscopy may detect some adenomas missed with standard high-definition colonoscopy, it should not be used for routine colon cancer screening in average-risk patients, new research suggests.
The newer technology slightly improved detection of flat and small adenomas, but it was similar to standard high-definition white light colonoscopy for detecting advanced neoplasms, according to the February 23rd online report in The American Journal of Gastroenterology.
The improved detection rates reported with high-definition chromocolonoscopy have come from studies in patients at increased risk for colorectal neoplasms, lead author Dr. Charles J. Kahi, from Indiana University School of Medicine, Indianapolis, and associates note. Whether this modality offers any benefit in average-risk patients, however, is unclear.
To investigate, the researchers randomized 660 average-risk patients to undergo either high-definition chromocolonoscopy or white-light colonoscopy at four centers in the US.
Nearly 55% of patients evaluated with chromocolonoscopy had at least one adenoma compared with 48.4% assessed with white light colonoscopy. The number of adenomas per patient was also slightly higher in the chromocolonoscopy group: 1.3 vs. 1.1. Neither of these differences was statistically significant.
Both methods were comparable in detection of advanced neoplasms. One invasive malignancy was detected in each group, neither of which was a flat adenoma.
Chromocolonoscopy detected significantly more small (<5 mm) adenomas per patient (0.8 vs. 0.7) and more flat adenomas (0.6 vs. 0.4) than did white light colonoscopy, but the absolute difference was small.
"Given the small magnitude and uncertain clinical significance of the differences, our findings do not support the routine performance of high-definition chromocolonoscopy for colorectal cancer screening in average-risk patients," the authors conclude.
Am J Gastroenterol 2010.