What’s the best approach for dysplasia surveillance in IBD?

Chromoendoscopy

Chromoendoscopy is superior in both the detection and long-term management of dysplasia in IBD when compared to high-definition white-light examination. Chromoendoscopy not only enhances dysplasia detection but further improves the definition of these lesions which then facilitates endoscopic management.

Human beings have an innate visual perception limitation due to our inability to perceive depth in the red/green wavelength of light compared to the blue wavelength. All of the improvements in scope magnification and resolution bump up against this fact of our biology. Blue dye enhances our ability to perceive depth in this milieu and therefore detect and define flat lesions.

The superiority of chromoendoscopy when using standard definition colonoscopes has been demonstrated repeatedly and set the stage for the 2015 SCENIC international consensus statement and a seismic shift in our endoscopic management of dysplasia in patients with colitis. This evidence base remains relevant because only 77% of colonoscopies performed in the United States are performed using high-definition equipment. Nearly one-quarter of our patients lack access to the newer equipment and therefore without chromoendoscopy are being surveyed outside of current guidelines.

Since the SCENIC statement multiple studies comparing chromoendoscopy with newer higher resolution colonoscopes have been performed. The vast preponderance of evidence has shown either a trend toward superiority or the outright superiority of chromoendoscopy when compared with high-definition white-light examination in detection and long-term management of dysplasia.

Chromoendoscopy has allowed us to increase our visual vocabulary in describing dysplasia in the setting of colitis and, thus, open the door to further innovation and perhaps adoption of artificial intelligence going forward. Our ability to classify lesions encountered in colitis mucosa has become more precise with the expanded terminology the dye-enhanced high-definition view affords, with the Frankfurt Advanced Chromoendoscopic IBD Lesion Classification being the best and most detailed example.

It is no accident that advanced endoscopists have universally adopted chromoendoscopy for the management of dysplastic lesions whether by mucosal resection or submucosal dissection techniques. Chromoendoscopy is recommended by all society guidelines because of these inherent advantages.

Is high-definition white-light “good enough” for surveilling our patients with colitis? The overall incidence of CRC in IBD has been declining which makes each colonoscopy count more. We are performing up to 88 colonoscopies in patients with colitis to find a single cancer (compared to 8 in non-IBD surveillance patients). We need to be performing fewer and more precise chromoendoscopic examinations. We are otherwise failing to serve our IBD patients by performing too many negative procedures at too high a cost. Our patients deserve more than merely “good enough.”

James F. Marion, MD, is professor of medicine at the Icahn School of Medicine at Mount Sinai and director of education and outreach at The Susan and Leonard Feinstein Inflammatory Bowel Disease Center of The Mount Sinai Hospital, both in New York. He is on the advisory board for Janssen.