Table 1. Basic characteristics of trunk melanoma patients in the training and internal validation cohorts.
| Factors | Define | Train (n=14,841) | Test (n=6,357) | All (n=21,198) |
|---|---|---|---|---|
| Age (years) | 59.89±15.64 | 60.02±15.49 | 59.93±15.60 | |
| Marriage | Married | 10,296 (69.38) | 4,484 (70.54) | 14,780 (69.72) |
| Divorced | 2,503 (16.87) | 1,005 (15.81) | 3,508 (16.55) | |
| Single | 890 (6.00) | 388 (6.10) | 1,278 (6.03) | |
| Other | 1,152 (7.76) | 480 (7.55) | 1,632 (7.70) | |
| Race | White | 14,700 (99.05) | 6,304 (99.17) | 21,004 (99.08) |
| Other | 141 (0.95) | 53 (0.83) | 194 (0.92) | |
| Sex | Male | 10,141 (68.33) | 4,308 (67.77) | 14,449 (68.16) |
| Female | 4,700 (31.67) | 2,049 (32.23) | 6,749 (31.84) | |
| Laterality | Left | 6,034 (40.66) | 2,692 (42.35) | 8,726 (41.16) |
| Right | 5,807 (39.13) | 2,374 (37.34) | 8,181 (38.59) | |
| Bilateral | 3,000 (20.21) | 1,291 (20.31) | 4,291 (20.24) | |
| Behavior | Behav1 | 6,735 (45.38) | 2,840 (44.68) | 9,575 (45.17) |
| Behav2 | 5,836 (39.32) | 2,542 (39.99) | 8,378 (39.52) | |
| Behav3 | 2,270 (15.30) | 975 (15.34) | 3,245 (15.31) | |
| Stage | I | 11,353 (76.50) | 4,852 (76.33) | 16,205 (76.45) |
| II | 1,906 (12.84) | 847 (13.32) | 2,753 (12.99) | |
| III | 1,386 (9.34) | 597 (9.39) | 1,983 (9.35) | |
| IV | 196 (1.32) | 61 (0.96) | 257 (1.21) | |
| T | T1 | 9,859 (66.43) | 4,233 (66.59) | 14,092 (66.48) |
| T2 | 2,511 (16.92) | 1,044 (16.42) | 3,555 (16.77) | |
| T3 | 1,368 (9.22) | 598 (9.41) | 1,966 (9.27) | |
| T4 | 1,103 (7.43) | 482 (7.58) | 1,585 (7.48) | |
| N | N0 | 14,213 (95.77) | 6,103 (96.00) | 20,316 (95.84) |
| N1 | 408 (2.75) | 187 (2.94) | 595 (2.81) | |
| N2 | 220 (1.48) | 67 (1.05) | 287 (1.35) | |
| Surgery | Surg1 | 7,935 (53.47) | 3,445 (54.19) | 11,380 (53.68) |
| Surg2 | 5,621 (37.87) | 2,420 (38.07) | 8,041 (37.93) | |
| Surg3 | 217 (1.46) | 88 (1.38) | 305 (1.44) | |
| Surg4 | 1,068 (7.20) | 404 (6.36) | 1,472 (6.94) | |
| LNSur | None | 6,276 (42.29) | 2,718 (42.76) | 8,994 (42.43) |
| 1–3 | 5,825 (39.25) | 2,509 (39.47) | 8,334 (39.32) | |
| 4+ | 339 (2.28) | 130 (2.04) | 469 (2.21) | |
| Others | 2,401 (16.18) | 1,000 (15.73) | 3,401 (16.04) | |
| SurgOth | None | 9,158 (61.71) | 3,901 (61.37) | 13,059 (61.60) |
| Yes | 5,683 (38.29) | 2,456 (38.63) | 8,139 (38.40) | |
| Radiation | No | 14,677 (98.89) | 6,267 (98.58) | 20,944 (98.80) |
| Yes | 164 (1.11) | 90 (1.42) | 254 (1.20) | |
| Chemotherapy | No | 14,605 (98.41) | 6,272 (98.66) | 20,877 (98.49) |
| Yes | 236 (1.59) | 85 (1.34) | 321 (1.51) | |
| Breslow | 0.7 [0.4, 1.4] | 0.7 [0.4, 1.3] | 0.7 [0.4, 1.4] | |
| Pretreatment LDH | Other | 13,288 (89.54) | 5,696 (89.60) | 18,984 (89.56) |
| Normal level | 1,112 (7.49) | 444 (6.98) | 1,556 (7.34) | |
| Above | 441 (2.97) | 217 (3.41) | 658 (3.10) | |
| Ulceration | No | 12,626 (85.08) | 5,427 (85.37) | 18,053 (85.16) |
| Yes | 2,215 (14.92) | 930 (14.63) | 3,145 (14.84) | |
| Mitotic | 0 [0, 2] | 0 [0, 2] | 0 [0, 2] | |
| Positive | No | 2,404 (16.20) | 1,018 (16.01) | 3,422 (16.14) |
| Yes | 6,220 (41.91) | 2,653 (41.73) | 8,873 (41.86) | |
| Other | 6,217 (41.89) | 2,686 (42.25) | 8,903 (42.00) | |
| Bone | No | 14,790 (99.66) | 6,343 (99.78) | 21,133 (99.69) |
| Yes | 51 (0.34) | 14 (0.22) | 65 (0.31) | |
| Brain | No | 14,791 (99.66) | 6,340 (99.73) | 21,131 (99.68) |
| Yes | 50 (0.34) | 17 (0.27) | 67 (0.32) | |
| Liver | No | 14,788 (99.64) | 6,344 (99.80) | 21,132 (99.69) |
| Yes | 53 (0.36) | 13 (0.20) | 66 (0.31) | |
| Lung | No | 14,758 (99.44) | 6,333 (99.62) | 21,091 (99.50) |
| Yes | 83 (0.56) | 24 (0.38) | 107 (0.50) | |
| Malignant | 1 | 9,378 (63.19) | 4,004 (62.99) | 13,382 (63.13) |
| >1 | 5,463 (36.81) | 2,353 (37.01) | 7,816 (36.87) | |
| Status | 0 | 12,167 (81.98) | 5,217 (82.07) | 17,384 (82.01) |
| 1 | 1,204 (8.11) | 505 (7.94) | 1,709 (8.06) | |
| 2 | 1,470 (9.90) | 635 (9.99) | 2,105 (9.93) | |
| Time (years) | 59.34±24.96 | 59.19±24.75 | 59.30±24.90 |
Data are present as n (%), median [range], or mean ± SD. LNSur, LN surgery; LN, lymph node; SurgOth, surgery other; LDH, lactate dehydrogenase; SD, standard deviation.