Table 2.
Comparison of categorical features between Japanese dataset and Western datasets
| Feature | Training set | Validation set | p Value | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MSKCC (n = 189) | Scandinavia (n = 815) | Italy* (n = 287) | Japan (n = 261) | |||||||||||
| Number | % | Number | % | % of missing data | Number | % | % of missing data | Number | % | % of missing data | versus Scandinavian | versus Italian* | versus MSKCC | |
| Sex | ||||||||||||||
| Male | 85 | 45.0 | 369 | 45.3 | 0.0 | 120 | 41.8 | 0.0 | 139 | 53.3 | 0.0 | < 0.001 | 0.018 | < 0.001 |
| Female | 104 | 55.0 | 446 | 54.7 | 167 | 58.2 | 122 | 46.7 | ||||||
| Oncologic diagnosis group | ||||||||||||||
| 1 | 52 | 27.3 | 173 | 21.3 | 0.4 | 63 | 22.0 | 2.4 | 60 | 23.0 | 0.0 | < 0.001 | 0.002 | 0.048 |
| 2 | 34 | 18.2 | 74 | 9.2 | 44 | 15.3 | 75 | 28.7 | ||||||
| 3 | 103 | 54.5 | 567 | 69.1 | 173 | 60.3 | 126 | 48.3 | ||||||
| Visceral metastases | ||||||||||||||
| Yes | 114 | 60.3 | 325 | 39.8 | 6.3 | 91 | 31.7 | 12.2 | 114 | 43.7 | 0.0 | 0.779 | 0.269 | 0.004 |
| No | 75 | 39.7 | 441 | 53.9 | 161 | 56.1 | 147 | 56.3 | ||||||
| Lymph node metastases | ||||||||||||||
| Yes | 36 | 18.8 | 169 | 20.8 | 61.6 | 96 | 33.4 | 15.7 | 71 | 27.2 | 0.0 | < 0.001 | < 0.001 | < 0.001 |
| No | 153 | 81.2 | 143 | 17.6 | 146 | 50.9 | 190 | 72.8 | ||||||
| Skeletal metastases | ||||||||||||||
| Solitary | 55 | 29.0 | 123 | 15.2 | 3.4 | 139 | 48.4 | 1.4 | 112 | 42.9 | 0.0 | < 0.001 | < 0.001 | < 0.001 |
| Multiple | 134 | 71.0 | 666 | 81.4 | 144 | 50.2 | 149 | 57.1 | ||||||
| Pathologic fracture status | ||||||||||||||
| Completed | 84 | 44.2 | 614 | 75.0 | 0.9 | 143 | 49.9 | 4.5 | 105 | 40.2 | 0.0 | < 0.001 | 0.021 | 0.493 |
| Impending | 105 | 55.8 | 196 | 24.1 | 131 | 45.6 | 156 | 59.8 | ||||||
| ECOG performance status | ||||||||||||||
| 0–2 | 93 | 49.2 | 558 | 68.5 | 0.0 | 123 | 42.9 | 20.2 | 166 | 63.6 | 0.0 | 0.333 | 0.099 | 0.016 |
| 3, 4 | 96 | 50.8 | 257 | 31.5 | 106 | 36.9 | 95 | 36.4 | ||||||
| Survival > 1 month | ||||||||||||||
| Yes | 173 | 91.5 | 707 | 86.7 | 0.0 | – | – | – | 240 | 91.9 | 0.028 | – | 0.864 | |
| No | 16 | 8.5 | 108 | 13.3 | – | – | – | 21 | 8.1 | |||||
| Survival > 3 months | ||||||||||||||
| Yes | 129 | 68.2 | 557 | 68.3 | 0.0 | 267 | 93.0 | 0.0 | 218 | 83.5 | 0.0 | < 0.001 | 0.001 | 0.001 |
| No | 60 | 31.8 | 258 | 31.7 | 20 | 7.0 | 43 | 16.5 | ||||||
| Survival > 6 months | ||||||||||||||
| Yes | 111 | 58.7 | 372 | 45.6 | 0.0 | – | – | – | 179 | 68.6 | 0.0 | < 0.001 | – | 0.036 |
| No | 78 | 41.3 | 443 | 54.4 | – | – | – | 82 | 31.4 | |||||
| Survival > 12 months | ||||||||||||||
| Yes | 79 | 41.8 | 241 | 29.6 | 0.0 | 181 | 63.1 | 0.0 | 152 | 58.2 | 0.0 | < 0.001 | 0.186 | 0.001 |
| No | 110 | 58.2 | 574 | 70.4 | 106 | 36.9 | 109 | 41.8 | ||||||
| Survival > 18 months | ||||||||||||||
| Yes | 59 | 31.2 | 156 | 19.1 | 0.0 | – | – | – | 113 | 43.3 | 0.0 | < 0.001 | – | 0.011 |
| No | 130 | 68.8 | 659 | 80.9 | – | – | – | 148 | 56.7 | |||||
| Survival > 24 months | ||||||||||||||
| Yes | 44 | 23.2 | 117 | 14.4 | 0.0 | – | – | – | 79 | 30.3 | 0.0 | < 0.001 | – | 0.109 |
| No | 145 | 76.8 | 815 | 85.6 | – | – | – | 182 | 69.7 | |||||
MSKCC = Memorial Sloan Kettering Cancer Center; ECOG = Eastern Cooperative Oncology Group; *the Italy dataset did not report survival at 1 or 6 months after surgery.