TABLE 1.

Epidemiology of immune-related adverse events (irAEs) and immune checkpoint inhibitor-related pneumonitis (ICI-P)

Characteristics	Comments	References
Frequency of ICI-P	5th cause of irAEs after skin toxicities, hepatitis, thyroiditis and colitis 2.6–4.8% all grades 0.6–2.0% for grades ≥3	[51, 57–59]
Increased risk of pneumonitis in NSCLC	Relative risk all grades: 1.33–1.43	[57, 58]
Increased risk of pneumonitis compared to chemotherapy	Relative risk all grades: 2.35–5.17 Relative risk grades ≥3: 1–4.19	[55, 58–60]
Increased risk of ICI-P with anti-PD-1/PD-L1 versus anti-CTLA-4 inhibitors	Relative risk all grades: 3.47–6.4 Unclear difference between anti-PD-1 and PD-L1 inhibitors	[51, 52, 55, 60]
Increased risk of ICI-P with ICI/ICI combotherapy vesus ICI monotherapy	3.48–3.68 for all grades	[55, 60]
Fatal ICI-P	Primary cause of lethal irAEs (35% of deaths) 13% fatality rate	[53, 55]

NSCLC: nonsmall cell lung carcinoma; PD-1: programmed cell death protein 1; PD-L1: programmed cell death ligand 1; CTLA: cytotoxic T-lymphocyte associated antigen.