Association Between the Severity of Immune-related Adverse Events and the Prognosis in Patients With Non-small Cell Lung Cancer Receiving Treatment With Immune Checkpoint Inhibitors

Background/Aim: Among patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICI), survival is reported to be longer in those experiencing immune-related adverse events (irAEs). We evaluated the progression-free survival (PFS) in the absence of further treatment after ICI therapy was discontinued because of the emergence of irAEs in patients with NSCLC. Patients and Methods: Data from patients with NSCLC in whom ICI therapy was discontinued because of the development of irAEs were retrospectively analyzed. The primary endpoint was the PFS from the last day of administration of ICIs, in the absence of any further treatment. Results: A total of 162 patients with NSCLC received treatment with ICIs between January 2016 and December 2021. Among them, ICI therapy was discontinued in 33 patients because of the appearance of irAEs. The median (95% confidence interval) PFS in the absence of any treatment after the last administration of ICIs was 7.2 (4.2-12.3) months. According to the Common Terminology Criteria for Adverse Events, the Cox proportional hazards model was used to identify the severity of irAEs, which were determined to be significantly associated with the PFS in the absence of any further treatment after the last administration of ICI therapy. Conclusion: Although the present study showed that the PFS in patients with NSCLC was relatively long in the absence of any further treatment after the last administration of ICIs, the PFS was associated with the severity of the irAEs, and some patients showed early disease progression or death.