Clinical diagnosis and treatment recommendations for immune checkpoint inhibitor‐related hematological adverse events

Immune checkpoint inhibitors (ICIs) are able to reactivate the immune system, thereby enhancing the anti‐tumor effects. However, over‐activated T cells may induce immune‐related adverse events (irAEs). Hematological irAEs are rarely reported which mainly represent monolineage cytopenia or pancytopenia, including autoimmune hemolytic anemia (AIHA), immune thrombocytopenia (ITP), neutropenia and aplastic anemia, sometimes even life‐threatening diseases such as hemophagocytic lymphohistiocytosis. Here, the clinical manifestations of hematological irAEs are summarized and recommendations for diagnosis and treatment proposed. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: • Hematological immune‐related adverse events (irAEs) caused by checkpoint inhibitors are rare and may sometimes be life‐threatening. This study summarizes the manifestations of hematological irAEs and proposes preliminary recommendations for diagnosis and treatment. WHAT THIS STUDY ADDS: • Much still remains unknown regarding hematological irAEs caused by checkpoint inhibitors. This study delineates the overview of hematological irAEs, and provides practical treatment suggestions, in particular addressing the issue of rechallenge.