Diagnosis More Challenging Than Detection With CADx
Commenting on the study, comoderator David G. Graham, MD, consultant gastroenterologist at University College London Hospital in England, remarked: “The key questions here relate to why are these systems underperforming in the proximal colon, and how can we improve this?”
Are these results “due to the very different appearance of adenomas in the distal colon vs the proximal colon on CADx (which is not what we see as endoscopists but seems to be what the systems are seeing), or is it due to a different characterization of polyps,” that is, more sessile serrated lesions in the proximal colon than in the distal colon, he asked.
Also commenting on the study was Raf Bisschops, MD, head of endoscopy at KU Leuven in Belgium. He remarked that the review underscores the fact that optical diagnosis by artificial intelligence is a more challenging task than detection.
It is “not entirely clear” what would explain the difference in performance of CADx between the distal colon and proximal colon, he said. It can’t be excluded that the inclusion of different CADx systems, some of which clearly underperformed, may account for the difference.
He went on to suggest that the differences might be down to location beyond proximal and distal.
“The difference in performance between the right and left colon is also interesting, since recent insights in the molecular and morphological features of hyperplastic polyps indicates that there are different classes with more goblet cell–rich hyperplastic polyps in the right colon, and more microvesicular hyperplastic polyps in the left.”
These have “distinct microscopic and endoscopic appearances” that could account for a difference in performance of a CADx system if not included in the training and validation sets, he explained.
Rizkala and Graham reported no relevant disclosures. Bisschops reported receiving research grants and speaker fees from Medtronic, Fujifilm, and Pentax.
A version of this article first appeared on Medscape.com.
