Maintenance treatment of immunotherapy after microwave ablation plus drug-eluting bead bronchial arterial chemoembolization for advanced non-small cell lung cancer: a retrospective single-center cohort study

Background: The combination therapy of immunotherapy and drug-eluting bead bronchial artery chemoembolization (DEB-BACE) or microwave ablation (MWA) has been attempted as an effective and safe approach for advanced non-small cell lung cancer (NSCLC). However, the outcomes of immunotherapy plus multiple interventional techniques for advanced NSCLC remain unclear. This retrospective study thus aimed to investigate the effectiveness and safety of the maintenance treatment of programmed cell death protein 1 (PD-1) blockade after MWA plus DEB-BACE for advanced NSCLC. Methods: This retrospective cohort study consists of 95 patients with advanced NSCLC who were treated with DEB-BACE between April 2017 and October 2022 and who were allocated to three groups: group A (MWA + DEB-BACE + PD-1 blockade; n=15), group B (MWA + DEB-BACE; n=25), and group C (DEB-BACE alone; n=55). The adverse events (AEs) were compared between the three groups. The outcomes were compared via Kaplan-Meier methods, including median progression-free survival (PFS) and overall survival (OS). Survival analyses were performed via the univariate and multivariate analyses to investigate the prognostic predictors. Results: The overall incidence of AEs in the groups A-C was 53.3% (8/15), 36.0% (9/25), and 32.7% (18/55), respectively, which did not represent a significant difference (P=0.42). No severe AEs (SAEs) occurred. Group A, compared with group B and group C, had a significantly longer estimated median PFS (33.0 vs. 7.0 vs. 3.0 months; P<0.001) and OS (33.0 vs. 13.0 vs. 6.0 months; P=0.002). PD-1 blockade (P=0.006), tumor number (P=0.01), and DEB-BACE/bronchial artery infusion (BAI) chemotherapy cycles (P=0.04) were identified as the predictors of PFS, while the predictors of OS were PD-1 blockade (P<0.001), number of metastases (P<0.001), tumor diameter (P<0.001), and DEB-BACE/BAI cycles (P=0.02). Conclusions: Compared with that of advanced NSCLC treated with MWA plus DEB-BACE or DEB-BACE alone, the maintenance treatment of immunotherapy after MWA plus DEB-BACE might provide a superior prognosis without increasing the risk of AEs.