The widespread use of immune checkpoint inhibitors (ICIs), particularly Programmed cell death protein 1/programmed death ligand 1(PD-1/PD-L1) inhibitors, has significantly improved the survival prognosis of patients with various malignancies but has also brought about unique immune-related adverse events (irAEs). Among these, ICI-related immune thrombocytopenia (ITP), a rare but potentially life-threatening hematologic adverse event, is gaining increasing clinical attention. This article systematically reviews the pathogenic mechanisms of ITP associated with PD-1/PD-L1 inhibitors and explores the potential role of the PD-1/PD-L1 pathway in the pathogenesis of primary ITP. A deep understanding of the bidirectional relationship between the PD-1/PD-L1 pathway and ITP is of great significance for optimizing the safety management of tumor immunotherapy and exploring novel therapeutic strategies for ITP.
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