Table 1.

Baseline patients’ characteristics

Characteristics	No.	%
Age at diagnosis (median, IQR)	71 (56-78)	—
29-60	38	30.4
61-70	23	18.4
71-80	44	35.2
81-94	19	15.2
Unknown	1	0.8
Gender
Female	61	48.8
Male	64	51.2
Primary melanoma subtype
Acral	3	2.4
Cutaneous	96	76.8
Mucosal	8	6.4
Unknown	18	14.4
ECOG performance status
0	84	67.2
1	26	20.8
2	3	2.4
Unknown	12	9.6
Serum LDHa
Normal level for female	28	22.4
≥Upper limit of normal for female	26	20.8
Normal level for male	25	20.0
≥Upper limit of normal for male	34	27.2
Unknown	12	9.6
BRAF mutation
Present	29	23.2
Absent	79	63.2
Unknown	17	13.6
Number of metastases sites
1	54	43.2
2	34	27.2
≥3	36	28.8
Unknown	1	0.8
Brain metastases
Present	23	18.4
Absent	101	80.8
Unknown	1	0.8
Immunotherapy before to anti-PD-1b
Yes	38	30.4
No	86	68.8
Unknown	1	0.8
Targeted therapy before anti-PD-1c
Yes	29	23.2
No	95	76.0
Unknown	1	0.8
Chemotherapy before anti-PD-1
Yes	11	8.8
No	113	90.4
Unknown	1	0.8
Radiotherapy		0.0
Yes	59	47.2
No	65	52.0
Unknown	1	0.8
Stage
III	9	7.2
IV	115	92.0
Unknown	1	0.8
Treatment regimen
Pembrolizumab	73	58.4
Nivolumab	52	41.6
TNM stage (AJCC 8th Ed.)
III	9	7.2
M1a	28	22.4
M1b	16	12.8
M1c	48	38.4
M1d	23	18.4
Unknown	1	0.8
Number of immune related adverse events (irAE)
0	76	60.8
1	32	25.6
2	12	9.6
≥3	5	4.0
Vital status
Deceased	87	69.6
Alive	38	30.4
Total	125	100.0

ECOG, Eastern Oncology Cooperative Group; IQR, interquartile range; LDH, lactate dehydrogenase; No./%, number and percentage of patients; PD-1, programmed cell death protein 1.

^aNormal LDH levels: 135-214 U/l for females, 135-225 U/l for males.

^bA total of 21 patients received first-line ipilimumab, and 17 received second-line ipilimumab.

^cBRAF/MEK inhibitor (n = 16; 12.8%); BRAF inhibitor (n = 4; 3.2%); MEK inhibitor (n = 6; 4.8%); imatinib (n = 3; 2.4%).