Alessandro Repici1, Camilla Ciscato2, Loredana Correale2, Raf Bisschops3, Pradeep Bhandari4, Evelien Dekker5, Oliver Pech6, Franco Radaelli7, Cesare Hassan2. 1. Digestive Endoscopy Unit, Istituto Clinico Humanitas Research Hospital, Milan, Italy; Digestive Endoscopy Unit, Istituto Clinico Humanitas University, Milan, Italy. 2. Digestive Endoscopy Unit, Istituto Clinico Humanitas Research Hospital, Milan, Italy. 3. Department of Gastroenterology, University Hospitals Leuven, Leuven, Belgium. 4. Departments of Gastroenterology and Endoscopy, Portsmouth Hospitals NHS trust, Portsmouth, United Kingdom. 5. Department of Gastroenterology and Hepatology, Academic Medical Center Amsterdam, University of Amsterdam, The Netherlands. 6. Department of Gastroenterology and Interventional Endoscopy, Krankenhaus Barmherzige Brüder (St. John of God Hospital), Teaching Hospital of the University of Regensburg, Regensburg, Germany. 7. Gastroenterology Unit, Valduce Hospital, Como, Italy.
Abstract
BACKGROUND AND AIMS: The Narrow-band Imaging International Colorectal Endoscopic (NICE) Classification has been validated for differentiating hyperplastic from adenomatous polyps. This classification system was based on narrow-band imaging (NBI) technology, leaving uncertainty regarding its applicability to other systems. The aim of this study was to assess accuracy and reliability of histologic predictions for polyps <1 cm by applying the NICE classification to the Fujinon Spectral Imaging Color Enhancement (FICE) System. METHODS: A video library of 55 polyps <1 cm histologically verified with FICE was prospectively created, including polyps that fulfilled inclusion criteria (morphology, size, histology) in consecutive colonoscopies. Six endoscopists with experience in electronic chromoendoscopy independently reviewed the polyp images, scored the polyps as adenomatous or hyperplastic, and assigned a level of confidence to the predictions. Twenty videos were reassessed at 6 months. The diagnostic performances of the endoscopists was calculated both combined and individually according to the histopathology of the polyps. A mixed-effect logistic regression model, in which polyps were considered as random effects, and polyp histology, confidence level, and readers were considered as fixed effects, was used. Results were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: Of the 55 polyps (mean size 4.6 mm), 29 (53%) were adenomas, and 26 (47%) were hyperplastic. Across all the readers and observations, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the curve (AUC) were 77%, 75%, 88%, 75%, 77%, and 0.82, respectively. Individual rater accuracy ranged from 66% to 96%, being <90% in 5 of 6 cases. Overall, 68.5% of predictions (226/330) were made with high confidence, although there was high variability (Fleiss kappa, 0.15; 95% CI, 0.08-0.22). Sensitivity, specificity, PPV, NPV, accuracy, and AUC for predictions made with high confidence were 81%, 80.5%, 80%, 77%, 82%, and 0.88 being significantly more accurate as compared with a low confidence of diagnosis (OR 2.4; 95% CI, 1.2-4.7). Regarding the performance of the individual NICE criteria, the odds of adenoma detection were 3.4 (95% CI, 1.8-6.3) and 4.0 (95% CI, 2.1-7.5) by using surface and vessels patterns alone, as compared with the color criterion. Interrater and intrarater agreement with the NICE was only moderate (interrater: Fleiss kappa, 0.51; 95% CI, 0.44-0.56; intrarater: kappa, 0.40; 95% CI, 0.20-0.60). CONCLUSIONS: The application of the NICE classification to FICE resulted in suboptimal accuracy and only moderate interobserver agreement.
BACKGROUND AND AIMS: The Narrow-band Imaging International Colorectal Endoscopic (NICE) Classification has been validated for differentiating hyperplastic from adenomatous polyps. This classification system was based on narrow-band imaging (NBI) technology, leaving uncertainty regarding its applicability to other systems. The aim of this study was to assess accuracy and reliability of histologic predictions for polyps <1 cm by applying the NICE classification to the Fujinon Spectral Imaging Color Enhancement (FICE) System. METHODS: A video library of 55 polyps <1 cm histologically verified with FICE was prospectively created, including polyps that fulfilled inclusion criteria (morphology, size, histology) in consecutive colonoscopies. Six endoscopists with experience in electronic chromoendoscopy independently reviewed the polyp images, scored the polyps as adenomatous or hyperplastic, and assigned a level of confidence to the predictions. Twenty videos were reassessed at 6 months. The diagnostic performances of the endoscopists was calculated both combined and individually according to the histopathology of the polyps. A mixed-effect logistic regression model, in which polyps were considered as random effects, and polyp histology, confidence level, and readers were considered as fixed effects, was used. Results were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: Of the 55 polyps (mean size 4.6 mm), 29 (53%) were adenomas, and 26 (47%) were hyperplastic. Across all the readers and observations, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the curve (AUC) were 77%, 75%, 88%, 75%, 77%, and 0.82, respectively. Individual rater accuracy ranged from 66% to 96%, being <90% in 5 of 6 cases. Overall, 68.5% of predictions (226/330) were made with high confidence, although there was high variability (Fleiss kappa, 0.15; 95% CI, 0.08-0.22). Sensitivity, specificity, PPV, NPV, accuracy, and AUC for predictions made with high confidence were 81%, 80.5%, 80%, 77%, 82%, and 0.88 being significantly more accurate as compared with a low confidence of diagnosis (OR 2.4; 95% CI, 1.2-4.7). Regarding the performance of the individual NICE criteria, the odds of adenoma detection were 3.4 (95% CI, 1.8-6.3) and 4.0 (95% CI, 2.1-7.5) by using surface and vessels patterns alone, as compared with the color criterion. Interrater and intrarater agreement with the NICE was only moderate (interrater: Fleiss kappa, 0.51; 95% CI, 0.44-0.56; intrarater: kappa, 0.40; 95% CI, 0.20-0.60). CONCLUSIONS: The application of the NICE classification to FICE resulted in suboptimal accuracy and only moderate interobserver agreement.
Authors: Sharmila Subramaniam; Bu Hayee; Patrick Aepli; Erik Schoon; Milan Stefanovic; Kesavan Kandiah; Sreedhari Thayalasekaran; Asma Alkandari; Paul Bassett; Emmanuel Coron; Oliver Pech; Cesare Hassan; Helmut Neumann; Raf Bisschops; Alessandro Repici; Pradeep Bhandari Journal: United European Gastroenterol J Date: 2019-01-06 Impact factor: 4.623