Immune Checkpoint Inhibitor–Associated Pericarditis

Abstract Side effects of immune checkpoint inhibitors, termed immune-related adverse events (irAEs), are relatively common but immune checkpoint inhibitor mediated cardiotoxicity are rare, although can be serious and potentially fatal. Pericarditis is an infrequent cardiac toxicity of immunotherapy and predisposing factors remain unknown. Here we report 3 patients with non-small cell lung cancer who developed pericarditis during therapy with PD-1/PD-L1 +/- CTLA-4 inhibitors. We review the clinical presentation of these 3 cases and histopathologic findings from autopsies from the first 2 patients and a pericardial sampling that has been obtained from a pericardial window procedure in the 3 rd patient, who recovered from the pericarditis episode. We also discuss the potential mechanisms, as well as what is known about pericarditis secondary to irAEs.