Table 3.

Characteristics of patients with or without skin reaction during nivolumab or pembrolizumab monotherapy (n = 155)a

	With skin reactionb	Without skin reactionc		Multivariate
Variables	(n = 51)	(n = 104)	p value	p valued
Sex (male)	42 (82)	75 (72)	.23e
Age, years	68 [36–88]	69 [31–88]	.67f
ECOG PS, 0/1/≥2	36/13/2	53/49/2	1.00e
Pathological subtype
Squamous cell carcinoma	19	36	.89e
Nonsquamous NSCLC	32	68
Smoking (never or ex/current)	6/45	21/83	.28e
Past regimens	1.5 [0–7]	1.8 [0–9]	.05f	.38
PD‐L1 expression
TPS ≥ 50% (strong positive)	15 (29)	18 (17)
1% ≤ TPS < 50% (weak positive)	8 (16)	27 (26)
<TPS 1% (negative)	4 (8)	18 (17)
TPS unknown	24 (47)	41 (40)
IgG	1,367 [569–3,118]	1,275 [481–3,185]	.49f
IgA	285 [102–1,114]	263 [54–576]	.37g
IgM	75 [18–200]	87 [14–370]	.55f
IgE	365 [5–3,900]	244 [5–8,900]	.36g
Pre‐existing RFh	22 (43)	20 (19)	.003e	.002
Pre‐existing ANAi	22 (43)	29 (28)	.09e	.06
Pre‐existing antithyroidj	13 (25)	15 (15)	.14e	.15

^aMedian [range] or n (%).

^bPatients who developed skin reaction during nivolumab or pembrolizumab monotherapy.

^cPatients who did not develop skin reaction during nivolumab or pembrolizumab monotherapy.

^dBy logistic regression.

^eBy chi‐square test.

^fBy Mann‐Whitney U test.

^gBy Welch's t test.

^hA patient was considered positive if rheumatoid factor was >15 IU/mL at pretreatment.

ⁱA patient was considered positive if antinuclear antibody was ≥1:40 at pretreatment.

^jA patient was considered positive if either antithyroglobulin or antithyroid peroxidase was present at pretreatment.

Abbreviations: ANA, antinuclear antibody; ECOG PS, Eastern Cooperative Oncology Group performance status; Ig, immunoglobulin; NSCLC, non‐small cell lung cancer; PD‐L1, programmed cell death ligand 1; RF, rheumatoid factor; TPS, tumor proportion score.