Background: Prior research indicates a connection between immune-related adverse events (irAEs) and improved progression-free survival (PFS) and overall survival (OS) in non-small cell lung cancer. However, limited data exists for extensive stage small cell lung cancer (ES-SCLC).
Methods: This study included all ES-SCLC patients who received at least one dose of an immune checkpoint inhibitor between 2 January 2011 and 4 July 2022 using a large retrospective registry from a single institution. PFS and OS were right-censored at the date of last follow-up and were estimated using the Kaplan-Meier method. Differences in PFS and OS between irAE groups were assessed using Cox proportional hazards models.
Results: Among 245 patients with ES-SCLC; 56 (23%) experienced irAEs, 24 (42.9%) of which were high-grade (3-4). High-grade irAEs occurred at a median of 1.2 months (interquartile range [IQR] 0.45-2.5), while low-grade irAE occurred at 2.8 months (1.3-5.2). PFS was significantly longer among any irAE vs none (HR = 0.49; [95%CI 0.32-0.77]) as was OS (HR = 0.49; [95%CI 0.34-0.72]).
Conclusions: In ES-SCLC patients treated with immunotherapy, those who experienced any irAE demonstrated a two-fold increase in both PFS and OS compared to those without an irAE. This is consistent with other tumor primaries.
Keywords: Immunotherapy; adverse events; extensive stage small cell lung cancer; outcomes; survival.
This study looked at the link between side effects from a type of cancer medicine, immunotherapy, and survival in patients with a type of lung cancer called extensive-stage small cell lung cancer (ES-SCLC). Immunotherapy helps the immune system fight cancer. The side effects are called immune-related adverse events (irAEs). These side effects, caused by treatment inflammation, have been linked to longer survival in many cancers. Since small cell lung cancer is rare, it hasn’t been studied as much. This study found that patients with this cancer also lived longer when they had these side effects.