The effect of consolidation immunotherapy on patients with stage III non-small cell lung cancer who received induction chemoimmunotherapy: a multicenter retrospective study

Purpose The purpose of this study was to evaluate the effect of consolidation immunotherapy on patients with stage III non-small cell lung cancer (NSCLC) who received induction chemoimmunotherapy before chemoradiotherapy (CRT). Materials and methods Patients with stage III NSCLC who received induction chemoimmunotherapy before CRT with or without consolidation immunotherapy at 4 hospitals between February 2018 and December 2022 were retrospectively analyzed. The patients were divided into two groups on the basis of whether they received consolidation immunotherapy (Ind+Con group) or not (Ind group). Progression-free survival (PFS) and overall survival (OS) were assessed from the initiation of treatment and were estimated using the Kaplan–Meier method. One-to-one propensity score matching (PSM) was used to further minimize confounding effects. Results A total of 196 eligible patients were enrolled, with 124 (63.3%) in the Ind group and 72 (36.7%) in the Ind+Con group. The median follow-up was 24.6 months, and the median PFS and OS for the whole cohort were 24.8 months and 46.0 months, respectively. The median PFS was 25.5 months in the Ind group vs. 24.0 months in the Ind+Con group, with 2-year PFS rates of 52.2% vs. 47.7% (P = 0.472). The median OS was 46.0 months in the Ind group vs. not reached (NR) in the Ind+Con group, with 2-year OS rates of 78.0% vs. 83.8% (P = 0.578). After 1:1 PSM, the median PFS was 30.2 months vs. 24.0 months, with 2-year PFS rates of 55.4% vs. 47.7% (P = 0.261). The median OS was 46.0 months vs. NR, with 2-year OS rates of 80.8% vs. 83.8% (P = 0.960). Conclusion The effect of consolidation immunotherapy on patients with stage III NSCLC who receive induction chemoimmunotherapy before CRT needs to be further studied.