Biomarker role of thyroid irAE and PD-L1 positivity in predicting PD-1 blockade efficacy in patients with non-small cell lung cancer

Thyroid immune-related adverse events (irAEs) are associated with programmed cell death protein 1 (PD-1) blockade efficacy in non-small cell lung cancer (NSCLC). However, their independence from PD-L1 expression and quantitative impact on predicting PD-1 blockade efficacy remain unexplored. This multicenter, retrospective, longitudinal study from Korea included 71 metastatic NSCLC patients who underwent PD-L1 expression and thyroid function testing during PD-1 blockade. Disease progression by the Response Evaluation Criteria for Solid Tumors was the main outcome. Three-stage analyses were performed: (1) multivariate Cox regression models adjusted for PD-L1 expression according to thyroid irAEs; (2) subgroup analyses; (3) regrouping and comparing predictivity of current and alternative staging. Patients with thyroid irAE + exhibited a longer progression-free survival [7/20 vs. 34/51, adjusted HR 0.19 (0.07–0.47); P