Prospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 14, 2019; 25(10): 1278-1288
Published online Mar 14, 2019. doi: 10.3748/wjg.v25.i10.1278
Non-guided self-learning program for high-proficiency optical diagnosis of diminutive and small colorectal lesions: A single-endoscopist pilot study
Marco Bustamante-Balén, Carla Satorres, Lorena Puchades, Belén Navarro, Natalia García-Morales, Noelia Alonso, Marta Ponce, Lidia Argüello, Vicente Pons-Beltrán
Marco Bustamante-Balén, Carla Satorres, Noelia Alonso, Marta Ponce, Lidia Argüello, Vicente Pons-Beltrán, Gastrointestinal Endoscopy Research Group, Gastrointestinal Endoscopy Unit, Digestive Diseases Department, La Fe Polytechnic University Hospital, Valencia 46026, Spain
Lorena Puchades, Digestive Diseases Department, La Fe Polytechnic University Hospital, Valencia 46026, Spain
Belén Navarro, Natalia García-Morales, Gastrointestinal Endoscopy Unit, Digestive Diseases Department, La Fe Polytechnic University Hospital, Valencia 46026, Spain
Author contributions: Navarro B, Satorres C and Garcia-Morales N performed the literature research and reviewed the manuscript draft; Puchades L acquired data for analysis and reviewed the manuscript draft; Alonso N, Ponce M, Argüello L and Pons-Beltrán V revised the article for important intellectual content; Bustamante-Balén M conceived of and designed the project, contributed to data analysis, drafted the initial manuscript, and reviewed the different versions of the manuscript.
Institutional review board statement: The study protocol was approved by the Hospital La Fe Institutional Review Board, No. 2014/0074.
Informed consent statement: Informed consent was obtained from each patient.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Data sharing statement: No additional data are available.
CONSORT 2010 statement: The authors have read the CONSORT 2010 Statement, and the manuscript was prepared and revised according to the CONSORT 2010 Statement.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Marco Bustamante-Balén, MD, PhD, Doctor, Gastrointestinal Endoscopy Research Group, Gastrointestinal Endoscopy Unit, Digestive Diseases Department, La Fe Polytechnic University Hospital, Avda. Fernando Abril Martorell, 106, Valencia 46026, Spain.
Telephone: +34-96-12440225 Fax: +34-96-1246278
Received: December 31, 2018
Peer-review started: January 2, 2019
First decision: January 30, 2019
Revised: February 20, 2019
Accepted: February 22, 2019
Article in press: February 23, 2019
Published online: March 14, 2019
Research background

The resect-and-discard strategy for the management of diminutive colon polyps is a paradigm shift based on an accurate optical diagnosis (OD). Such a high accuracy has only been achieved by experts, while the performance in community hospitals does not reach thresholds that would allow its universal implementation. The lack of a standardized learning tool for OD of colon lesions may contribute to this problem.

Research motivation

Although several learning tools have been described, most of them are not validated and there is a great variability in their components and designs. We hypothesized that self-learning of OD is feasible and that accuracy thresholds can be achieved with a self-administered program. A detailed description of the learning process can provide valuable information for the design of an OD learning system.

Research objectives

We aimed to assess the accuracy of OD of diminutive lesions in real colonoscopies using the International Colorectal Endoscopic classification system for narrow band imaging after following a non-guided self-administered learning program. We also aimed to describe in detail the learning process by analyzing which parameters may be more suitable for monitoring competency.

Research methods

An experienced endoscopist followed a self-designed, self-administered learning program in OD of colorectal lesions. Then, OD was applied to lesions detected in colorectal cancer screening colonoscopies. The study period was divided in two halves, with a 6-mo period in between with no performance of OD. Sensitivity, specificity, predictive values and accuracy of the OD compared to the pathological report were calculated for overall results and for the two halves of the study. The accomplishment of the Preservation and Incorporation of Valuable Endoscopic Innovations (PIVI) criteria and the evolution of performance parameters through blocks of 50 lesions were also assessed.

Research results

Overall, 152 patients and 522 lesions were included in the analysis. Regarding the accomplishment of the PIVI criteria, the negative predictive value for the OD of adenoma in rectal lesions diagnosed with high confidence was 92.6% (95% confidence interval: 86.4-97.6) and the proportion of agreement on surveillance interval between OD and pathological diagnosis following the different guidelines was over 95%. Overall accuracy for diminutive lesions diagnosed with high confidence was 89.5% (95% confidence interval: 85.7-92.3). Specificity, negative predictive value and accuracy were the parameters most affected by the stopping period between the two halves. Analyzing trends on blocks of 50 lesions showed an improvement in sensitivity (P = 0.02) only in the first half of the study and an improvement on accuracy (P = 0.01) only in the second half.

Research conclusions

This study shows that a self-administered learning program based on still pictures plus an in vivo phase with auto-feedback is feasible to reach quality standards on OD of colorectal lesions. It also shows that a non-practice period deteriorates performance, and in that case a refresher course seems advisable. These results have practical implications in the design of OD learning tools and in the development of a quality monitoring system.

Research perspectives

These data have become the base for the design and validation of a self-administered learning tool that are currently in process. The efficacy of this kind of tool should be tested with endoscopists having different levels of experience and being from different backgrounds.