Table 2.

Patient demographic, clinical, and treatment characteristics*

Characteristic	All patients (N=124)	Non-progressors (N=14)	Resistant (N=110)
Age
Mean (SD)	59.5 (12.4)	58.2 (12.7)	59.7 (12.4)
Gender (binary)
Female	57 (46.0)	5 (35.7)	52 (47.3)
Male	67 (54.0)	9 (64.3)	58 (52.7)
Histology
Acral	76 (61.3)	10 (71.4)	66 (60.0)
Mucosal	44 (35.5)	4 (28.6)	40 (36.4)
Unknown primary†	4 (3.2)	0 (0.0)	4 (3.6)
BRAF status
Patients with data	122	14	108
V600	15 (12.3)	4 (28.6)	11 (10.2)
WT	105 (86.1)	10 (71.4)	95 (88.0)
Other	2 (1.6)	0 (0.0)	2 (1.9)
M stage at baseline biopsy‡
M0	6 (4.8)	3 (21.4)	3 (2.7)
M1a	44 (35.5)	2 (14.3)	42 (38.2)
M1b	9 (7.3)	1 (7.1)	8 (7.3)
M1c	65 (52.4)	8 (57.1)	57 (51.8)
ECOG performance status
1	123 (99.2)	14 (100)	109 (99.1)
2	1 (0.8)	0 (0.0)	1 (0.9)
Rounds of previous systemic therapies
0	108 (87.1)	14 (100)	94 (85.5)
1	15 (12.1)	0 (0.0)	15 (13.6)
2	1 (0.8)	0 (0.0)	1 (0.9)
Type of anti-PD-1 treatment
Nivolumab	20 (16.1)	4 (28.6)	16 (14.5)
Pembrolizumab	104 (83.9)	10 (71.4)	94 (85.5)
Number of cycles received
Median (range)	10 (2–67)	33 (14–67)	8 (2–64)
Duration of anti-PD-1 treatment (months)
Median (range)	6.3 (1.3–45.0)	23.2 (9.4–38.4)‡	5.4 (1.3–45.0)

*All values given as N (%) unless otherwise stated.

†Only those unknown primary tumors with the clinical appearance of mucosal melanoma were included in the study.

‡M0, no distant metastases; M1a, non-visceral metastases to skin, soft tissue including muscles, and/or non-regional lymph nodes; M1b, distant metastases to the lung; M1c, all other visceral metastases and any distant metastases with elevated lactase dehydrogenase levels.

§Nine non-progressors were still on anti-PD-1 therapy at the time of data cut-off and were not included.

BRAF, B-raf proto-oncogene serine/threonine kinase; ECOG, Eastern Cooperative Oncology Group; PD-1, programmed cell death-1; WT, wild type.