Effect of Neoadjuvant Immunotherapy Combined with Chemotherapy on Pulmonary Function and Postoperative Pulmonary Complications in Esophageal Cancer: A Retrospective Study

Background: Neoadjuvant immunotherapy, targeting the PD-1 or PD-L1, combined with chemotherapy (NICT), can improve the radical resection and survival rates for locally advanced EC. However, it may impair pulmonary function, and the effect of NICT on pulmonary function and postoperative pulmonary complications in EC patients remains unknown. This study aimed to investigate whether NICT can affect pulmonary functions and postoperative pulmonary complications in EC patients. Methods: The study retrospectively recruited 220 EC patients who received NICT at the Department of Esophageal Cancer in Tianjin Medical University Cancer Institute & Hospital from January 2021 to June 2022. Changes in pulmonary function before and after NICT were compared. Logistic regression analysis was performed to analyze the correlations of pulmonary functions and clinical characteristics with postoperative pulmonary complications, respectively. Results: The FEV1% pred, FVC, FVC% pred, and FEV1/FVC% significantly increased after NICT, with a P-value of 0.018, 0.005, 0.001, and 0.036, respectively. In contrast, there was a significant decline in the DLCO (8.92 +/- 2.34 L before NICT vs. 7.79 +/- 2.30 L after NICT; P < 0.05) and DLCO% pred (102.97 +/- 26.22% before NICT vs. 90.18 +/- 25.04% after NICT; P < 0.05). High DLCO and DLCO% pred at baseline levels were risk factors for DLCO reduction in EC patients after NICT. Advanced age, smoking history, FEV1% pred after NICT, and FVC% pred baseline and after therapy were risk factors for postoperative pulmonary complications, with a P-value of 0.043, 0.038, 0.048, 0.034, and 0.004, respectively. Although the DLCO level decreased after NICT, it did not increase the incidence of postoperative pulmonary complications. Conclusion: NICT may improve pulmonary ventilation function but also lead to a decrease in DLCO and DLCO% pred in EC patients. Nevertheless, the decreased DLCO after NICT did not increase the risk of postoperative pulmonary complications.