BACKGROUND: Durvalumab consolidation after concurrent chemoradiotherapy (CCRT) is the present standard of care for patients with unresectable stage III non-small cell lung cancer (NSCLC). However, some patients experience early recurrence. This study sought risk factors for early recurrence during durvalumab consolidation. METHODS: This retrospective multicenter study was conducted between September 2017 and September 2022. We categorized patients into early and non-early recurrence groups. Early recurrence was defined as recurrence within 6 months after the first dose of durvalumab. RESULTS: Of the 222 patients, 40 (18.0%) experienced early recurrence and 182 (82.0%) experienced non-early recurrence. The former group was younger than the latter group (P=0.02). Patients exhibiting lower-level programmed cell death-ligand 1 (PD-L1) expression were more likely to experience early recurrence (P=0.02). Stage IIIC patients tended to experience more early recurrence than stage IIIA/IIIB patients (P=0.055). Multivariate analyses revealed that older age [odds ratio (OR), 0.945
95% confidence interval (CI): 0.902-0.991
P=0.02] and PD-L1 level ≥50% (OR, 0.303
95% CI: 0.125-0.736
P=0.008) protected against early recurrence in NSCLC patients on durvalumab consolidation. Median overall survival was significantly longer in the non-early recurrence group than in the early recurrence group (non-evaluable CONCLUSIONS: Younger age and lower PD-L1 expression predicted early recurrence during durvalumab consolidation after CCRT. Careful follow-up of such patients is essential.