Treatment outcome and safety of durvalumab after concurrent chemoradiation in very elderly patients with unresectable stage III non-small cell lung cancer.

Background: Consolidation durvalumab after concurrent chemoradiotherapy (CCRT) has shown a significantly improved progression-free survival (PFS) and overall survival (OS) in patients with unresectable stage III non-small cell lung cancer (NSCLC). However, data on very elderly patients remain limited. This study evaluated the outcomes and safety of durvalumab after CCRT in very elderly patients compared to younger individuals. Methods: We reviewed all unresectable stage III patients with NSCLC treated with durvalumab after CCRT from 2020 to 2024 at four Korean hospitals. Patients were divided into two groups: aged <75 years and ≥75 years. Subgroup analyses using 65- and 70-year cutoffs were also performed. Endpoints included PFS, OS, and adverse events (AEs). Results: Among 46 patients, 13 were aged ≥75 years. The baseline characteristics including performance status and comorbidities were similar. The median PFS was 29 months in patients aged <75 years and 14 months in those aged ≥75 years (P=0.03). The median OS was not reached in patients aged <75 years and was 40 months in those aged ≥75 years (P=0.16). Three-year OS was 75.2% in patients aged <75 years and 57.7% in those aged ≥75 years (P=0.16). AEs rates were comparable between groups. Conclusions: In patients aged ≥75 years with unresectable stage III NSCLC, durvalumab after CCRT was associated with shorter PFS and comparable AE profiles to younger patients. OS appeared similar, but the small sample size limits interpretation. Comprehensive geriatric assessment may help guide treatment decisions before initiating durvalumab after CCRT in very elderly patients.