Clinical features, diagnostic challenges, and management strategies in checkpoint inhibitor-related pneumonitis

Abstract
Clinical features, diagnostic challenges, and management strategies in checkpoint inhibitor-related pneumonitis Sarah Chuzi,1 Fabio Tavora,2 Marcelo Cruz,3 Ricardo Costa,3 Young Kwang Chae,3 Benedito A Carneiro,3 Francis J Giles3 1Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; 2Argos Laboratory, Messejana Heart and Lung Hospital, Fortaleza, Brazil; 3Developmental Therapeutics Program, Division of Hematology/Oncology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA Immune checkpoint inhibitors, including cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death-1 (PD-1) inhibitors, represent an effective treatment modality for multiple malignancies. Despite the exciting clinical benefits, checkpoint inhibition is associated with a series of immune-related adverse events (irAEs), many of which can be life-threatening and result in significant treatment delays. Pneumonitis is an adverse event of special interest as it led to treatment-related deaths in early clinical trials. This review summarizes the incidence of pneumonitis during treatment with the different checkpoint inhibitors and discusses the prognostic significance of tumor type. The wide range of clinical, radiographic, and histologic characteristics of checkpoint inhibitor-related pneumonitis is reviewed and followed by guidance on the different management strategies. Keywords: immune checkpoint inhibitors, pneumonitis, anti-PD-1, anti-CTLA-4, immune-related adverse event