Factors associated with immune-related thyroid dysfunction induced by PD-1/PD-L1 inhibitors in cancer patients: an observational study

This study aimed to identify the potential factors associated with immune thyroid dysfunction caused by programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors in cancer patients. We conducted a retrospective study of thyroid immune-related adverse events (irAEs) in cancer patients treated with PD-1/PD-L1 inhibitors at Tianjin First Central Hospital from January 2020 to March 2023. Thyroid irAEs were characterized as hypothyroidism, hyperthyroidism and thyrotoxicosis followed by hypothyroidism. A total of 175 patients were screened in the study, of whom 48 patients (27%) developed thyroid irAEs (including 24 hypothyroidism, 11 hyperthyroidism and 13 thyrotoxicosis followed by hypothyroidism) following PD-1/PD-L1 inhibitors treatment. Multivariate logistic regression analysis showed that combination therapy with PD-1/PD-L1 inhibitors and tyrosine kinase inhibitors (lenvatinib/regorafenib) and high baseline anti-TPO level were associated with the development of thyroid irAEs caused by PD-1/PD-L1 inhibitors. The nomogram models showed good discriminant ability and could bring net benefits for more patients according to the decision curve analysis. However, the model needs to be further validated in other large cohorts.