Purpose: Computer-aided diagnosis systems for polyp characterization are commercially available but cannot recognize subtypes of sessile lesions. This study aimed to develop a computer-aided diagnosis system to characterize polyps using non-magni ed white-light endoscopic images.Methods: A total of 2249 non-magni ed white-light images from 1030 lesions including 534 tubular adenomas, 225 sessile serrated adenoma/polyps and 271 hyperplastic polyps in the proximal colon were consecutively extracted from an image library and divided into training and testing datasets (4:1), based on the date of colonoscopy. Using ResNet-50 networks, we developed a classi er (1) to differentiate adenomas from serrated lesions, and another classi er (2) to differentiate sessile serrated adenoma/polyps from hyperplastic polyps. Diagnostic performance was assessed using the testing dataset. The computer-aided diagnosis system generated a probability score for each image, and a probability score for each lesion was calculated as the weighted mean with a log 10 -transformation. Two experts (E1, E2) read the identical testing dataset with a probability score.Results: The area under the curve of classi er (1) for adenomas was equivalent to E1 and superior to E2 (classi er 86%, E1 86%, E2 69%; classi er vs. E2, p<0.001). In contrast, the area under the curve of classi er (2) for sessile serrated adenoma/polyps was inferior to both experts (classi er 55%, E1 68%, E2 79%; classi er vs. E2, p<0.001).
Conclusion:The classi er (1) developed using white-light images alone compares favorably with experts in differentiating adenomas from serrated lesions. However, the classi er (2) to identify sessile serrated adenoma/polyps is inferior to experts.