Related Experiment Video For Diagnosis and imaging (inc. chromoendoscopy, NBI, iSCAN, FICE, CLE...)
Updated: Jun 26, 2026
Evaluation of the Effectiveness of Longitudinal Incision for Endoscopic Submucosal Excavation of Gastric Subepithelial Lesions
Published on: April 28, 2026
Performance of an artificial intelligence system versus endoscopists for interrogation of scars after piecemeal
Oswaldo Ortiz1,2, Ricard Prat1, Guillem Soy1
1Hospital Clinic Barcelona, Gastroenterology Department, Endoscopy UnitUniversitat de BarcelonaBarcelonaSpain.
Background And Study Aims:
Detection and management of recurrence after piecemeal endoscopic mucosal resection (p-EMR) of large colorectal polyps is crucial for preventing post-colonoscopy colorectal cancer. Colonoscopy assisted with artificial intelligence systems for lesion detection (CADe) has shown efficacy in identifying polyps, particularly small lesions (< 10 mm). Our aim was to evaluate sensitivity and negative predictive value of CADe compared with endoscopists in detecting recurrence after p-EMR.
Methods:
Sixty-six pseudo anonymized high-quality videos (25 with recurrence and 15 with previously clipped defects) of > 15 mm polyps post-EMR scars were assessed. Recurrence size was < 10 mm in 19 of 25 cases (76.0%). Six endoscopists-three experts and three non-experts-predicted recurrence (yes/no) with confidence level (high/low). The same videos were analyzed with CAD-e detection mode superimposed. The gold standard was histopathology.
Results:
Endoscopists had higher sensitivity than CADe (96.0% vs 72.0%; P = 0.03). Experts performed better than non-experts in ruling out recurrence (specificity: 92.7% vs 58.5%; P = 0.001) and accuracy (92.4% vs 72.7%; P < 0.001). In non-clipped defects, endoscopists maintained higher sensitivity than CADe (95.0% vs 65.0%; P = 0.03). Concordance was moderate overall (Kappa 0.57) but substantial among experts (0.70) and when excluding clipped defects (0.61).
Conclusions:
Endoscopists outperformed CADe in interrogating post-EMR scars. Training CADe with images of post-polypectomy scars may further improve its performance.
