Published online Jan 21, 2021. doi: 10.3748/wjg.v27.i3.281
Peer-review started: October 9, 2020
First decision: November 23, 2020
Revised: December 5, 2020
Accepted: December 22, 2020
Article in press: December 22, 2020
Published online: January 21, 2021
Non-magnifying endoscopy with narrow-band imaging (NM-NBI) has been frequently used in routine screening of esophagus squamous cell carcinoma (ESCC). The performance of NBI for screening of early ESCC is, however, significantly affected by operator experience. Artificial intelligence may be a unique approach to compensate for the lack of operator experience.
To construct a computer-aided detection (CAD) system for application in NM-NBI to identify early ESCC and to compare it with our previously reported CAD system with endoscopic white-light imaging (WLI).
A total of 2167 abnormal NM-NBI images of early ESCC and 2568 normal images were collected from three institutions (Zhongshan Hospital of Fudan University, Xuhui Hospital, and Kiang Wu Hospital) as the training dataset, and 316 pairs of images, each pair including images obtained by WLI and NBI (same part), were collected for validation. Twenty endoscopists participated in this study to review the validation images with or without the assistance of the CAD systems. The diagnostic results of the two CAD systems and improvement in diagnostic efficacy of endoscopists were compared in terms of sensitivity, specificity, accuracy, positive predictive value, and negative predictive value.
The area under receiver operating characteristic curve for CAD-NBI was 0.9761. For the validation dataset, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CAD-NBI were 91.0%, 96.7%, 94.3%, 95.3%, and 93.6%, respectively, while those of CAD-WLI were 98.5%, 83.1%, 89.5%, 80.8%, and 98.7%, respectively. CAD-NBI showed superior accuracy and specificity than CAD-WLI (P = 0.028 and P ≤ 0.001, respectively), while CAD-WLI had higher sensitivity than CAD-NBI (P = 0.006). By using both CAD-WLI and CAD-NBI, the endoscopists could improve their diagnostic efficacy to the highest level, with accuracy, sensitivity, and specificity of 94.9%, 92.4%, and 96.7%, respectively.
The CAD-NBI system for screening early ESCC has higher accuracy and specificity than CAD-WLI. Endoscopists can achieve the best diagnostic efficacy using both CAD-WLI and CAD-NBI.
Core Tip: The computer-assisted diagnosis (CAD) system under conventional endoscopic white-light imaging (WLI) for screening of early esophagus squamous cell carcinoma (ESCC) has high accuracy. However, few studies have examined different characteristics of CAD application in WLI and narrow-band imaging (NBI) models. In this study, the CAD system we constructed under the NBI model for screening of early ESCC had higher accuracy and specificity than the CAD-WLI system. Endoscopists could achieve the best diagnostic efficacy by using both CAD-WLI and CAD-NBI. The two CAD systems have different advantages in avoiding missed diagnosis and excessive biopsy, which could help endoscopists, especially those with less experience, in more efficient screening of early ESCC.