Abstract
BACKGROUND: The efficacy of neoadjuvant immunotherapy in resectable non-small-cell lung cancer (NSCLC) is controversial. The aim of this study is to explore the efficacy of additional PD-1/PD-L1 inhibitors in the neoadjuvant treatment of resctable NSCLC. METHODS: Data sources included Cochrane Library, Embase, Web of Science, and PubMed from beginning of the database creation to May 2024. The primary outcomes of the study included event-free survival (EFS), overall survival (OS), pathological complete response (pCR), major pathological response (MPR). RESULTS: Seven RCTs, including 2929 patients, were included in the analysis. The results showed that the experimental group had significantly higher rates of pCR (RR = 5.9, p < 0.001) and MPR (RR = 2.88, p < 0.001) compared to the control group. OS (HR = 0.57) and EFS (HR = 0.58) was also significantly improved in the experimental group. Subgroup analysis of EFS revealed that the benefit was higher in the East (HR = 0.56) than in the West (HR = 0.70). Additionally, the benefit seemed to rise with PD-L1 tumor cell proportion score (TPS) (TPS < 1%, HR = 0.76; 1% < TPS < 49%, HR = 0.56; TPS ≥ 50%, HR = 0.38). The benefit degree seemed to be higher in the III period patients (HR = 0.75) than I-II period patients (HR = 0.52). It is important to emphasize that smokers (HR = 0.54, p < 0.001) benefited from neoadjuvant immunotherapy but nonsmokers (HR = 0.68, p = 0.055) did not. CONCLUSION: Neoadjuvant PD-1/PD-L1 inhibitor combined with chemotherapy can significantly improve the short-term and long-term prognosis of patients with resectable NSCLC. Moreover, the efficacy of this treatment regimen may be affected by different clinicopathological characteristics of patients.