Table 1.
Clinicopathological characteristics of children with bone tumor.
| Total (N = 2,059) | Training cohort (N = 1,215) | Validation cohort (N = 844) | p | |
|---|---|---|---|---|
| Age (median [IQR]) | 13 (10, 15) | 13 (10, 15) | 13 (10, 15) | 0.6892 |
| Race | 0.717 | |||
| White | 1,624 (78.9%) | 955 (78.6%) | 669 (79.3%) | |
| Black | 233 (11.3%) | 143 (11.8%) | 90 (10.7%) | |
| Other | 202 (9.81%) | 117 (9.63%) | 85 (10.1%) | |
| Sex | 0.020 | |||
| Male | 1,179 (57.3%) | 722 (59.4%) | 457 (54.1%) | |
| Female | 880 (42.7%) | 493 (40.6%) | 387 (45.9%) | |
| Grade | 0.933 | |||
| I | 23 (1.12%) | 14 (1.15%) | 9 (1.07%) | |
| II | 48 (2.33%) | 27 (2.22%) | 21 (2.49%) | |
| III | 419 (20.3%) | 248 (20.4%) | 171 (20.3%) | |
| IV | 747 (36.3%) | 433 (35.6%) | 314 (37.2%) | |
| Unknown | 822 (39.9%) | 493 (40.6%) | 329 (39.0%) | |
| Stage | 0.591 | |||
| Localized | 673 (32.7%) | 398 (32.8%) | 275 (32.6%) | |
| Regional | 842 (40.9%) | 484 (39.8%) | 358 (42.4%) | |
| Distant | 531 (25.8%) | 325 (26.7%) | 206 (24.4%) | |
| Unstaged | 13 (0.63%) | 8 (0.66%) | 5 (0.59%) | |
| Year of diagnosis | 0.651 | |||
| 2004–2010 | 860 (41.8%) | 502 (41.3%) | 358 (42.4%) | |
| 2010–2018 | 1,199 (58.2%) | 713 (58.7%) | 486 (57.6%) | |
| Primary site | 0.713 | |||
| Limb | 1,576 (76.5%) | 926 (76.2%) | 650 (77.0%) | |
| Cranial | 93 (4.52%) | 55 (4.53%) | 38 (4.50%) | |
| Spine | 56 (2.72%) | 35 (2.88%) | 21 (2.49%) | |
| Thoracic | 118 (5.73%) | 76 (6.26%) | 42 (4.98%) | |
| Pelvic | 216 (10.5%) | 123 (10.1%) | 93 (11.0%) | |
| Histologic type | 0.832 | |||
| Osteogenic sarcoma | 1,385 (67.3%) | 820 (67.5%) | 565 (66.9%) | |
| Ewings sarcoma | 674 (32.7%) | 395 (32.5%) | 279 (33.1%) | |
| Laterality | 0.789 | |||
| Left | 952 (46.2%) | 563 (46.3%) | 389 (46.1%) | |
| Right | 901 (43.8%) | 535 (44.0%) | 366 (43.4%) | |
| Not a paired site | 206 (10.0%) | 117 (9.63%) | 89 (10.5%) | |
| Chemotherapy | 0.189 | |||
| No/Unknown | 81 (3.93%) | 54 (4.44%) | 27 (3.20%) | |
| Yes | 1,978 (96.1%) | 1,161 (95.6%) | 817 (96.8%) | |
| Radiation | 0.937 | |||
| No/Unknown | 1,674 (81.3%) | 989 (81.4%) | 685 (81.2%) | |
| Yes | 385 (18.7%) | 226 (18.6%) | 159 (18.8%) | |
| Surgery | 0.926 | |||
| No | 321 (15.6%) | 193 (15.9%) | 128 (15.2%) | |
| Partial resection | 230 (11.2%) | 136 (11.2%) | 94 (11.1%) | |
| Radical excision | 1,166 (56.6%) | 681 (56.0%) | 485 (57.5%) | |
| Amputation | 342 (16.6%) | 205 (16.9%) | 137 (16.2%) | |
| Tumor size (median [IQR]) | 90 (62, 125) | 90 (63, 125) | 88.5 (61.75, 125.25) | 0.7592 |
| Metastasis | 0.469 | |||
| No/Unknown | 1,585 (77.0%) | 928 (76.4%) | 657 (77.8%) | |
| Yes | 474 (23.0%) | 287 (23.6%) | 187 (22.2%) |