Efficacy and safety of perioperative immunotherapy combinations for resectable non-small cell lung cancer: a systematic review and network meta-analysis

Introduction Several trials of perioperative immunotherapy for resectable non-small cell lung cancer (NSCLC) reported positive results. They were designed to adjuvant, neoadjuvant and sandwich (neoadjuvant plus adjuvant) immunotherapy with immune checkpoint inhibitors and chemotherapy (CT). The differences between neoadjuvant and sandwich modalities were unclear. Method We performed a systematic review and Bayesian network meta-analysis by retrieving relevant literature from PubMed, EMBASE, Cochrane Library, Web of Science, ClinicalTrials.gov, WHO ICTRP and major international conferences. Results We analyzed 8 studies involving 3429 patients, including 6 neoadjuvant plus adjuvant (Neo-Adj) and 2 neoadjuvant (Neo) trials. Neo-Adj had better event-free survival (EFS) (hazard ratio [HR] = 0.57, 95% confidence interval [CI]: 0.45-0.71) than CT. There existed no difference between Neo-Adj and Neo in EFS (HR = 0.87, 95% CI: 0.53-1.46) and overall survival (OS) (HR = 1.04, 95% CI: 0.38-2.57). Neo might have lower incidence of treatment-related adverse events (TRAEs) (relative risk [RR] = 0.96, 95% CI: 0.87-1.12) than Neo-Adj. Subgroup analysis of PD-L1 >= 50% suggested that EFS of Neo-Adj (HR = 0.46, 95% CI: 0.27-0.76) and Neo (HR = 0.24, 95% CI: 0.06-0.89) was better than CT, and Neo-Adj potentially caused shorter EFS than Neo (HR = 1.92, 95% CI: 0.46-7.84). Conclusions Our results suggest that Neo-Adj and Neo have similar EFS for patients with PD-L1 < 1% or 1-49%. However, patients with PD-L1 >= 50% may obtain more EFS benefit from Neo than Neo-Adj. Neo might present a more favorable assessment than Neo-Adj when evaluating OS. Moreover, adding adjuvant immunotherapy may increase toxicity.