Analyze the correlation between the conformity of the anatomy (based on endoscopic examination) and postoperative anastomotic fistula and anastomotic stenosis; establish an anastomotic classification; and construct a predictive model combined with perioperative-related test indicators to provide more accurate risk assessment for clinical practice. Analyze the natural recovery process of postoperative recurrent laryngeal nerve injury in esophageal cancer by tracking vocal cord movement (based on endoscopic examination) and hoarseness symptoms; combined with perioperative related surgical and laboratory indicators, identify the relevant risk factors associated with delayed recovery of recurrent laryngeal nerve injury.