Table 1.

Baseline characteristics

Factor	Category	N	%
Age	≤50 years	5	33.3
	>50 years	4	26.7
	>60 years	2	13.3
	>70 years	4	26.7
Gender	Male	9	60.0
	Female	6	40.0
M category	M1a	6	40.0
	M1b	2	13.3
	M1c	7	46.7
Prior systemic treatments for metastatic disease	BRAF inhibitor/MEK inhibitor	6	40.0
	Chemotherapy	11	73.3
Treatment line	Second line	15	100
	Third line	2	13.3
Presence of brain metastasis	Yes	0	0
	No	15	100
Subsequent treatments	None	8	53.3
	PD-1antibody/PD-L1antibody	2	13.3
	BRAF inhibitor/MEK inhibitor	4	26.7
	Chemotherapy	4	26.7
ECOG	0	14	6.7
	1	1	93.3
IL-2 doses	8	12	80.0
	7	2	13.3
	5	1	6.7
Ipilimumab doses	4	11	73.3
	3	1	6.7
	2	2	13.3
	1	1	6.7
LDH	Elevated	8	53.3
	Normal	7	46.7

ECOG eastern cooperative oncology group, IL-2 interleukin-2, LDH lactate dehydrogenase, PD-1 programmed death-1, PD-L1 programmed death ligand-1