The Learning Curve And Interobserver Agreement Of Confocal Laser Endomicroscopy For Esophageal Squamous Intraepithelial Neoplasia And Early Stage Of Esophageal Squamous Carcinoma

Background&Objective:Confocal laser endomicroscopy (CLE) is used in clinical to detect esophageal squamous intraepithelial neoplasia (ESIN), and the early stage of esophageal squamous cell carcinoma (ESCC) at subcelluar resolution in vivo.But the learning curve for interpretation of eCLE images in the precancerous or early stage of esophageal squamous cancers is unknown. The aim of this article is to evaluate the accuracy and inter-observer agreement of CLE for differentiation of esophagus lesions among experienced and in-experienced observers and construct a learning curve for in-experienced assessors.Method:An experienced CLE endoscopist selected72pairs of high quality images from the data base. We divided the selected images into4groups according to the random numbers. There are22endoscopists in our stud, including8experienced observers who were very familiar with CLE and14inexperienced endoscopists who knew nothing about CLE. After about half an hour’training, including the detailed interpretation of the SMS and10images (5benign and5malignant) with known histology results, all the endoscopists were asked to evaluate the four sets of selected high quality images independently. Their results were corrected and discussed after each set. The diagnostic results, confidence, quality and time used in the evaluation process for each image were recorded. After a session of study, every observer took a fifteen minutes’rest.Result:The accuracy of the inexperienced observers for the first,second,third,and fourth sets of images were76.6%,88.7%,96.4%,96.0%respectively,and the accuracy of the experienced observers were92.4%,91.0%,95.1%,95.1%respectively. Compared with the interpretation of the first set of images, odds of the diagnostic accuracy for the second,third,fourth set of images were2.0195%CI(1.22-3.31),7.9595%CI(3.74～16.87),6.4595%CI(3.14～13.27) respectively, with no difference between the third and fourth sets(P0.66). Previous experience effected on the interpretation of esophagus lesions only in the first set of images (OR3.7095%CI (1.87～7.29), P<0.001). The inter-observer agreement for interpretation of esophageal lesions of experienced group was higher than that of inexperienced group (0.732vs.0.666p<0.01) When observers were confident of their diagnosis, the accuracy could reach a high level (experienced observers98.8%,inexperienced observers group94.7%) The time used to make diagnosis markedly decreased from group1to group4among in-experienced observers.Conelusion:CLE is a promising technology with high sensitivity, specificity, accuracy in the diagnosis of ESIN or ESCC that can be controlled quickly after a short training and learning. Previous experience was associated with high accuracy at the initial stage of learning.