Table 4.
Multivariable cox regression model in the training, internal validation, and external validation cohorts of OS.
| Variables | Training dataset | Internal validation cohort | External validation cohort | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| HR | 95% CI | P | HR | 95% CI | P | HR | 95% CI | P | ||
| Age | <60 | 1 | 1 | 1 | ||||||
| ≥60 | 1.283 | (1.200, 1.373) | <0.0001 | 1.195 | (1.102, 1.296) | <0.0001 | 1.48 | (1.131, 1.937) | 0.0043 | |
| Tumor location | Colon | 1.000 | 1 | 1 | ||||||
| Rectum | 0.832 | (0.762, 0.909) | <0.0001 | 0.728 | (0.652, 0.812) | <0.0001 | 0.427 | (0.294, 0.620) | <0.0001 | |
| Differentiation | Well | 1.000 | 1 | 1 | ||||||
| Moderately | 1.082 | (0.920, 1.273) | 0.3399 | 1.043 | (0.819, 1.329) | 0.7306 | 1.412 | (0.656, 3.042) | 0.378 | |
| Poorly | 1.564 | (1.317, 1.857) | <0.0001 | 1.489 | (1.161, 1.911) | 0.0017 | 2.26 | (1.007, 5.073) | 0.0481 | |
| Undifferentiated; anaplastic | 1.868 | (1.523, 2.291) | <0.0001 | 1.683 | (1.267, 2.235) | 0.0003 | 6.371 | (2.172, 18.691) | 0.0007 | |
| Unknown | 0.916 | (0.697, 1.204) | 0.5292 | 1.162 | (0.823, 1.641) | 0.3924 | 1.036 | (0.349, 3.076) | 0.9488 | |
| Histological type | Adenocarcinoma, NOS | 1 | 1 | 1 | ||||||
| Mucinous adenocarcinoma | 1.148 | (1.019, 1.293) | 0.0229 | 1.132 | (0.984, 1.302) | 0.0818 | 1.639 | (1.048, 2.564) | 0.0305 | |
| Signet ring cell carcinoma | 1.589 | (1.058, 2.386) | 0.0255 | 1.222 | (0.755, 1.980) | 0.4141 | 4.308 | (1.312, 14.148) | 0.0161 | |
| Other | 1.164 | (1.030, 1.317) | 0.0153 | 1.064 | (0.921, 1.230) | 0.3991 | 1.056 | (0.654, 1.705) | 0.8224 | |
| Size, mm | <55 | 1 | 1 | 1 | ||||||
| ≥55 | 1.223 | (1.147, 1.303) | <0.0001 | 1.11 | (1.027, 1.201) | 0.0089 | 1.272 | (0.972, 1.665) | 0.0799 | |
| TNM | IVA | 1 | 1 | 1 | ||||||
| IVB | 1.569 | (1.467, 1.677) | <0.0001 | 1.579 | (1.453, 1.715) | <0.0001 | 1.454 | (1.101, 1.921) | 0.0083 | |
| IVNOS | 1.187 | (0.966, 1.457) | 0.1028 | 1.188 | (0.924, 1.527) | 0.1797 | 2.114 | (1.053, 4.245) | 0.0352 | |
| Chemotherapy | Yes | 1.000 | 1 | 1 | ||||||
| None/unknown | 2.916 | (2.718, 3.129) | <0.0001 | 3.065 | (2.816, 3.336) | <0.0001 | 2.74 | (2.059, 3.647) | <0.0001 | |
| No. of sampled LNs | 0.977 | (0.973, 0.981) | <0.0001 | 0.979 | (0.974, 0.983) | <0.0001 | 0.961 | (0.943, 0.979) | <0.0001 | |
| No. of positive LNs | 1.053 | (1.047, 1.059) | <0.0001 | 1.049 | (1.041, 1.056) | <0.0001 | 1.026 | (1.003, 1.050) | 0.025 | |
| Metastatic surgery | Yes | 1.000 | 1 | 1 | ||||||
| No | 1.364 | (1.267, 1.469) | <0.0001 | 1.301 | (1.186, 1.428) | <0.0001 | 1.423 | (0.984, 2.058) | 0.0612 | |