Establishment and Evaluation of a Probe-based Confocal Laser Endomicroscopy Training System for Gastric Cancerous Lesions Diagnosis: Evidence from a National Training Program

Introduction: The learning process for probe-based confocal laser endomicroscopy (pCLE) is challenging, and standardized training protocols are currently lacking. The main purpose of this study is to establish and evaluate a preliminary pCLE training system. Methods: This prospective diagnostic trial was carried out based on the nationwide training program. The training system included online theoretical courses and a two-day offline training. All patients underwent pCLE and magnifying endoscopy (ME). The diagnostic performances of baseline levels, pCLE trainees, pCLE experts, and ME experts were evaluated and compared. The primary outcomes were the diagnostic accuracy, sensitivity, and specificity of gastric cancerous lesions. Linear regression analysis was adopted to explore the influence factors on the accuracy of trainees. Results: A total of 150 lesions and 127 endoscopists were enrolled. All diagnostic indicators for pCLE trainees exhibited significant improvement versus baseline levels (all P < 0.001). pCLE trainees exhibited significantly lower accuracy than pCLE experts (P = 0.036). There were no significant differences in accuracy, sensitivity and specificity between pCLE trainees and ME experts. pCLE experts showed significantly higher accuracy (P = 0.039) and specificity (P = 0.022) than ME experts. Professional title, hospital level, gastroscopy experience, ME experience, and educational degree exerted no significant influence on the accuracy of pCLE trainees. Conclusion: Short-term systematic pCLE training demonstrated significant efficacy, and the diagnostic performance of pCLE trainees was comparable to that of mature ME technology. pCLE can serve as an effective method to promptly enhance the diagnostic proficiency of endoscopists, especially novices, for gastric cancerous lesions.