Table 1 Description of the training and validation cohorts
Characteristic | Overall n = 14,200 | Training Cohort n = 11,360 | Validation Cohort n = 2,840 | p-value |
|---|---|---|---|---|
Age, years | 0.703 | |||
< 69 | 7,141 (50%) | 5,724 (50%) | 1,417 (50%) | |
69–76 | 4,614 (32%) | 3,695 (33%) | 919 (32%) | |
> 76 | 2,445 (17%) | 1,941 (17%) | 504 (18%) | |
Sex | 0.897 | |||
Female | 5,330 (38%) | 4,261 (38%) | 1,069 (38%) | |
Male | 8,870 (62%) | 7,099 (62%) | 1,771 (62%) | |
Race | 0.180 | |||
Black | 1,145 (8.1%) | 892 (7.9%) | 253 (8.9%) | |
Other | 696 (4.9%) | 557 (4.9%) | 139 (4.9%) | |
White | 12,359 (87%) | 9,911 (87%) | 2,448 (86%) | |
Laterality | 0.716 | |||
Left | 6,272 (44%) | 5,009 (44%) | 1,263 (44%) | |
Right | 7,928 (56%) | 6,351 (56%) | 1,577 (56%) | |
T stage | 0.427 | |||
T1 | 4,638 (33%) | 3,735 (33%) | 903 (32%) | |
T2 | 5,165 (36%) | 4,108 (36%) | 1,057 (37%) | |
T3 | 2,884 (20%) | 2,321 (20%) | 563 (20%) | |
T4 | 1,513 (11%) | 1,196 (11%) | 317 (11%) | |
N stage | 0.844 | |||
N0 | 10,138 (71%) | 8,106 (71%) | 2,032 (72%) | |
N1 | 2,476 (17%) | 1,982 (17%) | 494 (17%) | |
N2 | 1,533 (11%) | 1,232 (11%) | 301 (11%) | |
N3 | 53 (0.4%) | 40 (0.4%) | 13 (0.5%) | |
M stage | 0.751 | |||
M0 | 13,833 (97%) | 11,064 (97%) | 2,769 (98%) | |
M1 | 367 (2.6%) | 296 (2.6%) | 71 (2.5%) | |
Marital status | 0.672 | |||
Married | 8,055 (57%) | 6,454 (57%) | 1,601 (56%) | |
Other | 6,145 (43%) | 4,906 (43%) | 1,239 (44%) | |
Histologic | 0.608 | |||
Basaloid SCC | 154 (1.1%) | 117 (1.0%) | 37 (1.3%) | |
Kera SCC | 1,213 (8.5%) | 967 (8.5%) | 246 (8.7%) | |
Nonkera SCC | 667 (4.7%) | 530 (4.7%) | 137 (4.8%) | |
SCC | 12,166 (86%) | 9,746 (86%) | 2,420 (85%) | |
Grade | 0.501 | |||
I–II | 6,308 (44%) | 5,062 (45%) | 1,246 (44%) | |
III–IV | 6,346 (45%) | 5,078 (45%) | 1,268 (45%) | |
Unknown | 1,546 (11%) | 1,220 (11%) | 326 (11%) | |
Tumor size, mm | 0.178 | |||
< 20 | 2,372 (17%) | 1,928 (17%) | 444 (16%) | |
20–38 | 5,668 (40%) | 4,504 (40%) | 1,164 (41%) | |
> 38 | 6,160 (43%) | 4,928 (43%) | 1,232 (43%) | |
Primary site | 0.949 | |||
Lower | 4,936 (35%) | 3,958 (35%) | 978 (34%) | |
Middle | 594 (4.2%) | 476 (4.2%) | 118 (4.2%) | |
Other | 465 (3.3%) | 368 (3.2%) | 97 (3.4%) | |
Upper | 8,205 (58%) | 6,558 (58%) | 1,647 (58%) | |
Chemotherapy | 0.792 | |||
No/Unknown | 9,856 (69%) | 7,879 (69%) | 1,977 (70%) | |
Yes | 4,344 (31%) | 3,481 (31%) | 863 (30%) | |
Surgery | 0.975 | |||
Lobectomy | 13,132 (92%) | 10,506 (92%) | 2,626 (92%) | |
Pneumonectomy | 1,068 (7.5%) | 854 (7.5%) | 214 (7.5%) | |
Radiotherapy | 0.437 | |||
No/unknown | 12,236 (86%) | 9,776 (86%) | 2,460 (87%) | |
Yes | 1,964 (14%) | 1,584 (14%) | 380 (13%) | |
LNR | 0.798 | |||
≤ 0.15 | 12,217 (86%) | 9,764 (86%) | 2,453 (86%) | |
0.16–0.5 | 1,659 (12%) | 1,333 (12%) | 326 (11%) | |
> 0.5 | 324 (2.3%) | 263 (2.3%) | 61 (2.1%) | |
RNP | 0.744 | |||
Negative | 10,531 (74%) | 8,418 (74%) | 2,113 (74%) | |
Positive | 3,669 (26%) | 2,942 (26%) | 727 (26%) | |
RNE | 11.72 ± 8.97 | 11.72 ± 8.96 | 11.72 ± 9.03 | 0.995 |