Table 1.
Patient and disease characteristics at first exposure to CPI
| Patient and disease characteristic | Total (N=325) | Anti-PD-1 (N=184) | Anti-PD-1 +ipilimumab (N=59) | Ipilimumab (N=82) | P value* |
| Primary site - no. (%) | 0.55 | ||||
| Palmar Plantar Weight bearing Non-weight bearing Subungual Toenail Fingernail |
22 (7) 234 (72) 141 46 69 (21) 39 30 |
13 (7) 138 (75) 84 28 33 (18) 19 14 |
3 (5) 41 (70) 26 8 15 (25) 9 6 |
6 (7) 55 (67) 31 10 21 (26) 11 10 |
|
| Median age at diagnosis of advanced acral melanoma, years (range) | 66 (23–90) | 69 (31–90) | 64 (23–82) | 65 (31–85) | 0.002 |
| Sex - no. (%) | 0.47 | ||||
| Female Male |
154 (47) 171 (53) |
82 (45) 102 (55) |
29 (49) 30 (51) |
43 (52) 39 (48) |
|
| Ethnicity - no. (%) | 0.0003 | ||||
| Caucasian Non-Caucasian† Unknown |
252 (76) 64 (20) 9 (3) |
131 (71) 50 (27) 3 (2) |
46 (78) 9 (15) 4 (7) |
75 (92) 5 (6) 2 (2) |
|
| Mutation - positive/tested (% of tested) | 0.07 | ||||
| BRAF KIT NRAS |
38/312 (12) 23/235 (10) 54/264 (21) |
21/179 (12) 19/140 (14) 29/153 (19) |
10/55 (18) 1/45 (2) 11/49 (22) |
7/78 (9) 3/50 (6) 14/62 (23) |
|
| ECOG (%) | 0.13 | ||||
| 0 ≥1 Unknown |
170 (52) 110 (34) 45 (14) |
99 (54) 59 (32) 26 (14) |
27 (46) 28 (47) 4 (7) |
44 (54) 23 (28) 15 (18) |
|
| LDH | 0.01 | ||||
| Normal (≤ULN) Elevated (>ULN) Unknown |
135 (42) 69 (21) 121 (37) |
86 (47) 31 (17) 67 (36) |
19 (32) 20 (34) 20 (34) |
30 (37) 18 (22) 34 (42) |
|
| Stage (AJCC 8th edition) - no (%) | <0.0001 | ||||
| Unresectable III IV M1a M1 M1c M1d |
79 (24) 246 (76) 53 (16) 66 (20) 103 (32) 24 (7) |
57 (31) 127 (69) 33 (18) 43 (23) 45 (25) 6 (3) |
10 (17) 49 (83) 6 (10) 6 (10) 25 (42) 12 (20) |
12 (15) 70 (85) 14 (17) 17 (21) 33 (40) 6 (7) |
|
| De-novo metastatic disease - no (%) | 33 (10) | 20 (11) | 7 (12) | 6 (8) | 0.66 |
| Time from primary diagnosis to advanced disease, months (range) | 21 (0–261) | 18 (0–261) | 23 (0–131) | 24 (0–246) | 0.27 |
| Number of treatment lines for advanced disease prior to first CPI exposure | 0.0003 | ||||
| 0 1 2 |
256 (79) 62 (19) 7 (2) |
151 (82) 29 (16) 4 (2) |
54 (92) 5 (9) 0 |
51 (62) 28 (34) 3 (4) |
Bold values indicate significant results (P<0.05).
*Pearson’s χ2 test; Fisher’s exact test.
†Non-Caucasian includes: East Asian, South East Asian, Middle Eastern, Hispanic and black.
AJCC, American Joint Committee on Cancer; CPI, checkpoint inhibitor; ECOG, Eastern Cooperative Oncology Group; LDH, lactate dehydrogenase; PD-1, programmed cell death protein-1; ULN, upper limited of normal.