This study aimed to identify the risk factors of lymph node metastasis (LNM) in superficial esophageal squamous cell carcinoma and use these factors to establish a prediction model. We retrospectively analyzed the data from training set (n = 280) and validation set (n = 240) underwent radical esophagectomy between March 2005 and April 2018. Our results of univariate and multivariate analyses showed that tumor size, tumor invasion depth, tumor differentiation and lymphovascular invasion were significantly correlated with LNM. Incorporating these 4 variables above, model A achieved AUC of 0.765 and 0.770 in predicting LNM in the training and validation sets, respectively. Adding macroscopic type to the model A did not appreciably change the AUC but led to statistically significant improvements in both the integrated discrimination improvement and net reclassification improvement. Finally, a nomogram was constructed by using these five variables and showed good concordance indexes of 0.765 and 0.770 in the training and validation sets, and the calibration curves had good fitting degree. Decision curve analysis demonstrated that the nomogram was clinically useful in both sets. It is possible to predict the status of LNM using this nomogram score system, which can aid the selection of an appropriate treatment plan.

Esophagogastroduodenoscopy (EGD) is the pivotal procedure for diagnosis of upper gastrointestinal (UGI) lesions. However, significant variation in EGD performance among endoscopists impacts detection rates of UGI cancers and precursor lesions. We developed a novel EGD quality monitoring system and evaluated its effectiveness in a randomized controlled study. The endoscopy quality control assistant (EQCA) was developed using deep convolutional neural networks and long short-term memory. Patients (≥18 years) undergoing EGD in seven hospitals were consecutively enrolled and randomly assigned to the EQCA-assisted group or control group. The primary outcome was the detection rate for cancer-related lesions (low and high grade intraepithelial neoplasia and cancer) and cancer (early and advanced cancer) in the UGI tract. After randomization and exclusions, 16 005 patients in the control group and 16 012 in the EQCA group were analyzed. Detection rates for UGI cancer-related lesions and cancer were significantly higher in the EQCA group than in the control group (8.00% vs. 5.55%; 1.93% vs. 1.21%; both P < 0.001). The EQCA group had a higher operation score, reflecting examination quality, and longer inspection time than the control group. The detection rate for UGI cancer-related lesions was positively correlated with operation score (r = 0.9217, P < 0.001) and inspection time (r = 0.8943, P < 0.001) for each hospital. The use of EQCA during EGD was associated with increased detection of UGI cancer and precancerous lesions. Our novel EQCA system can be an effective tool for monitoring real-time EGD quality.

Background: Endoscopic submucosal dissection (ESD) is technically difficult with high rates of complications, such as perforation and bleeding. We aimed to explore the safety and cutting efficiency of a novelly devised bipolar knife for ESD procedure. Methods: Taking a traditional monopolar knife as a reference, the safety and feasibility of the novel bipolar knife were evaluated by an animal experiment and a human study. Furthermore, we assessed the usefulness and advantage of this novel bipolar knife by using the finite element method. Results: A porcine experiment confirmed that there was no significant difference in wound size and cutting speed between the monopolar and bipolar knives. The thermal damage and histopathological scores produced by the two knives were similar. In addition, the porcine experiment and patients' study identified that the incidence of postoperative complications, such as bleeding, perforation, and infection, had no statistical difference between the monopolar and bipolar groups. Finally, the finite element model showed that the length and depth of thermal damage caused by the bipolar knife were, respectively, 102.77–117.98% and 80.87–84.53% of those caused by the monopolar knife at the same power. Conclusion: The novel bipolar knife was theoretically safer than the monopolar knife and, at least, was confirmed not inferior to the monopolar knife in operability and cutting efficiency. Thus, the novel bipolar knife can be an alternative device choice for ESD.