Objective:To evaluate the relationship between preoperative malnutrition and postoperative pulmonary complications (PPCs) in elderly patients undergoing thoracoscopic and laparoscopic radical esophagectomy.Methods:The elderly patients who underwent elective thoracoscopic and laparoscopic radical esophagectomy in the Affiliated Hospital of Jiangnan University were enrolled.The general clinical data and nutritional status, Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) score, tumor pathological stage and operation-related variables based on the Gobal Leader Initiative on Malnutrition criteria were recorded.The patients were divided into 2 groups according to whether PPCs occurred during hospitalization, and the differences between the variables were compared.Logistic regression analysis was used to identify the risk factors for PPCs in elderly patients undergoing thoracoscopic and laparoscopic radical esophagectomy.The accuracy of the ARISCAT score and ARISCAT score combined with malnutrition in predicting the occurrence of PPCs was evaluated by receiver operating characteristic curve.Results:A total of 256 elderly patients undergoing thoracoscopic and laparoscopic radical esophagectomy were included, and the incidence of PPCs was 23.8%.There were no significant differences between patients with and without PPCs in FEV 1/FVC, age, American Society of Anesthesiologists physical status, chronic obstructive pulmonary disease ratio, malnutrition ratio and ratio of patients with high ARISCAT score ( P<0.05). The results of logistic regression analysis showed that increasing age, chronic obstructive pulmonary disease, malnutrition and high ARISCAT score were independent risk factors for PPCs.The area under the receiver operating characteristic curve of ARISCAT score and malnutrition combined with ARISCAT score in predicting the occurrence of PPCs was 0.722 and 0.777, respectively, and the difference was statistically significant ( P<0.05). Conclusions:Preoperative malnutrition is an independent risk factor for the occurrence of PPCs in elderly patients undergoing thoracoscopic and laparoscopic radical esophagectomy, which is helpful in improving the accuracy of ARISCAT score in predicting the occurrence of PPCs.