Table 1. Retrospective studies assessing the impact of baseline corticosteroids on the clinical outcome of advanced NSCLC treated with PD-(L)1 inhibitors.

Author	Type of study	Number of patients		Definition of steroid treatment	Immune checkpoint inhibitor	Reason for steroid use	Median overall survival (steroid vs. non-steroid users)	Significant covariates in multivariate analysis
		Steroids	No steroids
Arbour et al. (4)	Multicentric	90	550	Oral or intravenous corticosteroids equivalent to prednisone >10 mg/day on the day starting ICI treatment	Nivolumab; atezolizumab; pembrolizumab; durvalumab	Dyspnea or respiratory symptoms (33%)	IGR: 3.3 vs. 9.4 months, P<0.001	ECOG PS ≥2
						Fatigue (21%)	MSKCC: 5.4 vs. 12.1 months, P<0.001	Brain metastases
						Brain metastases (19%)		Corticosteroid >10 mg/day of prednisone or equivalent
Scott et al. (5)	Single institution	66	144	Oral or intravenous corticosteroids equivalent to prednisone >10 mg/day at initiation or within 30 days after ICI treatment	Nivolumab	COPD or respiratory symptoms (21%)	4.3 vs. 11 months, P=0.017	Age
						Disease-related pain and constitutional symptoms (18%)
						irAE (17%)		Corticosteroid >10 mg/day of prednisone or equivalent
						Brain metastases (27%)
Fucà et al. (3)	Single institution	35	116	Oral or intravenous corticosteroids equivalent to prednisone >10 mg/day for at least 1 day within 28 days after ICI treatment	Anti-CTLA-4 + anti-PD-L1: 6 patients	NA	4.86 vs. 15.14 months, P<0.001	ECOG PS ≥2
					Single agent anti-PD-(L)1: 145 patients			Corticosteroid >10 mg/day of prednisone or equivalent

COPD, chronic obstructive pulmonary disease; ECOG PS, Eastern Cooperative Oncology Group performance status; ICI, immune checkpoint inhibition; IGR, Institute Gustav Roussy; irAE, immune-related adverse event; mOS, median overall survival; NA, not available; PD-L1, programmed death-ligand 1; PD-1, programmed cell death-1; MSKCC, Memorial Sloan Kettering Cancer Center.