Abstract 312P
Background
The introduction of CT-IO has redefined first-line (1L) treatment for ES-SCLC, improving median overall survival (mOS) but increasing irAEs. While irAEs correlate with better OS in many cancers, their prognostic significance in ES-SCLC remains unclear.
Methods
We retrospectively analysed consecutive ES-SCLC pts treated with 1L CT-IO between January 2020 and September 2024 across 4 European centres. Demographic and clinical data were collected and the association between irAEs and progression-free survival (PFS) or OS was assessed.
Results
A total of 339 pts were included. Baseline characteristics are shown in the table. Median follow-up in censored pts was 29.4 months (m). Overall response rate was 80.4%, median PFS (mPFS) 6.1 m (95% CI 5.8–6.6) and mOS 10.2 m(95% CI 9.0–11.7). IrAEs occurred in 31.5% of pts, most commonly affecting the skin (11.8%). Median time to onset of first irAE was 173 days (IQR 100.5–238.2). Pts with irAEs had longer mPFS (10.8 vs. 5.3 m, p < 0.001) and mOS (18.7 vs. 7.5 m, p < 0.001) than those without. No significant difference was seen between pts with grade ≥3 irAEs (n=38) and pts with
Conclusions
This is the largest retrospective study to demonstrate that irAEs are associated with improved clinical outcomes in ES-SCLC pts receiving 1L CT-IO. Further research is needed to identify the irAE profiles linked to better outcomes.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
E. Bria: Financial Interests, Institutional, Research Grant: Roche. All other authors have declared no conflicts of interest.