[Immune checkpoint inhibitors induced pituitary immune-related adverse events: diagnosis and management]

Immune checkpoint inhibitors (ICIs) have been used in treating a wide variety of cancers, but they challenge clinicians with a series of special immune related adverse events (irAEs) resulting from activated immune system. Since June 2018, when the first programmed cell death 1 (PD-1) inhibitor, nivolumab, was approved by the National Medical Products Administration (NMPA), abundant experience has been accumulated in coping with irAEs from PD-1 and PD-1 ligand 1 (PD-L1) blockade therapies. In October 2021, the first CTLA-4 inhibitor, ipilimumab, which has a different spectrum of irAEs was also approved by NMPA. The discrepancy in clinical features of pituitary irAEs is obvious between these two types of ICIs. Pituitary irAEs include hypophysitis and hypopituitarism. In this review of latest literature, we have summarized the incidence, possible mechanisms, time of onset, clinical presentations, hormone test, pituitary imaging, treatment strategies and recovery patterns of pituitary irAEs. By referring to domestic and foreign clinical guidelines, we have proposed practical suggestions for screening, diagnosing and treating pituitary irAEs.