Immunotherapy Associated Autoimmune Hemolytic Anemia

Over the past decade, the role of immunotherapy in the treatment of cancer has expanded, and, more specifically, the indications for immune checkpoint inhibitors (ICI) have multiplied to include first-line therapy. ICIs include cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1) inhibitors. Those agents can be used as monotherapy or in combination. Autoimmune hemolytic anemia (AIHA) has emerged as a potential rare yet serious immune-related adverse event in the setting of ICI use. In this review, we describe our approach to the diagnosis and management of immunotherapy related AIHA- (ir-AIHA), proposing an algorithmic approach based on acuity and severity. We also discuss suggested mechanisms and review the prognosis of ir-AIHA including the risk of recurrence when patients are rechallenged with ICIs after a period of interruption in therapy.