Fig. 2

Subgroup analysis in all patients. A, B Forest plots for progression-free survival (A) and overall survival (B) across different patient subgroups, based on multivariate Cox analysis. C, D Kaplan–Meier plots of progression-free survival (C) and overall survival (D) in patients with PD-L1 CPS < 1. E, F Kaplan–Meier plots of progression-free survival (E) and overall survival (F) in patients with PD-L1 CPS 1–4. G, H Kaplan–Meier plots of progression-free survival (G) and overall survival (H) in patients with PD-L1 CPS ≥ 5. I, J Kaplan–Meier plots of progression-free survival (I) and overall survival (J) in patients with unknown PD-L1 CPS post-IPTW. Abbreviations: C, Chemotherapy alone; CPS, Combined positive score; dMMR, Deficient DNA mismatch repair; ECOG, Eastern Cooperative Oncology Group; HR, Hazard ratio; I + C (IC), Immune checkpoint inhibitors combined with chemotherapy; mOS, Median overall survival time; mPFS, Median progression-free survival time; MSI, Microsatellite instability; MSS, Microsatellite stable; PD-L1, Programmed death ligand 1; pMMR, Proficient DNA mismatch repair; N, Number; TMB, Tumor mutation burden