Neoadjuvant immune checkpoint inhibitor therapy and chemotherapy improve pulmonary ventilation and diffusion function in patients with lung cancer.

Objectives: To investigate changes of pulmonary ventilation function and diffusion function in lung cancer patients after neoadjuvant immune checkpoint inhibitors (ICIs) therapy combined with chemotherapy treatment.

Methods: Patients with newly diagnosed lung cancer (Ⅱa-Ⅲb) admitted to Zhejiang Cancer Hospital from October 2021 to July 2022, who received ICIs combined with chemotherapy for more than two courses were enrolled. Patients underwent pulmonary ventilation function and diffusion function assessments before and after treatment. The demographic information, sizes and locations of cancer lesions, doses and duration of ICIs used, pulmonary function results before and after treatment, and the tumor regression were documented. The changes of pulmonary function parameters before and after the treatment were analyzed with paired t test and Wilcoxon rank-sum test. The factors influencing the pulmonary function changes were analyzed by multiple linear Lasso regression and ridge regression.

Results: Among the 52 patients, 50 cases were males (96.15%) and 43 cases were squamous carcinoma (82.69%). The medium age of the patients was 67 years. After neoadjuvant therapy, 36 patients (69.23%) showed remission of tumor lesions. After treatment, the parameters of pulmonary ventilation inspiratory vital capacity (IVC) and the area under the expiratory flow-volume curve (AREAex), and the parameter of pulmonary diffusion total lung capacity increased compared with the baseline (all P<0.05). Forced vital capacity (FVC) and forced expiratory volume in first second (FEV₁) also showed an increasing trend. Multivariate linear Lasso regression and ridge regression showed that baseline IVC had a significant negative effect on IVC improvement (Beta=－0.435, t=－2.968, P<0.01), baseline TLC had a significant negative effect on the improvement of TLC (Beta=－0.266, t=－2.474, P<0.05), and the remission of obstructive pneumonia favored the improvement of TLC (Beta=0.308, t=2.443, P<0.05).

Conclusions: After ICIs neoadjuvant treatment combined with chemotherapy, the lung ventilation and diffusion function can be improved in lung cancer patients, particularly for those with reduced baseline ventilation and diffusion function.