Clinical and Radiological Features and Treatment of Pulmonary Toxicity Associated with Using Immune Checkpoint Inhibitors in Cancer Treatment: A Single-Center Experience

Abstract

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies and include cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death-1 (PD-1), and programmed cell death ligand-1 (PD-L1), which are becoming increasingly important in cancer treatment. 1 ICIs exert their anti-tumoral activity by increasing the activity of the immune system, especially T cells. 2 The United States Food and Drug Administration has approved many ICIs; for example, ipilimumab, an anti-CTLA-4 antibody, was the first agent approved in 2011 for melanoma patients. 3 PD-1 is targeted by pembrolizumab, nivolumab, and cemiplimab, while atezolizumab, durvalumab, and avelumab target PD-L1. They have been introducedfor the treatment of many solid and liquid cancers, such as malignant melanoma, non-small cell lung cancer (NSCLC), renal cell carcinoma, and cancers with impaired DNA damage repair (MSI-high). 4 More than 233,000 patients receive these agents annually as first-or next-line therapy. 5 ICIs are associated with several adverse events different from those of other conventional systemic therapies, such as cytotoxic chemotherapy, including decreased T-cell tolerance and uncontrolled activation of immunity, with unknown pathophysiology. 6 Although these adverse events can affect many organs and mostly the skin, they may affect the thyroid, adrenal, and pituitary glands, gastrointestinal tract, lung, kidney,