Table 3.
Univariate and Multivariate Analysis of Predictors of Overall Survival (OS)
| Factor | 5-year OS, % |
Median OS, mo |
Univariate Analysis |
Multivariate Analysis* |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Model 1 |
Model 2 |
||||||||||
| P | HR | 95% CI | P | HR | 95% CI | P | HR | 95% CI | |||
| DFI, years | |||||||||||
| <1 (n= 122) | 49.6 | 71.4 | .252 | 1.39 | 0.79-2.44 | ||||||
| ≥1 (n= 62) | 65.9 | 79.7 | |||||||||
|
| |||||||||||
| Primary tumor location | |||||||||||
| Rectum (n= 37) | 47.8 | 71.4 | .254 | 1.41 | 0.79-2.54 | ||||||
| Colon (n= 147) | 57.3 | 74.8 | |||||||||
|
| |||||||||||
| Primary tumor nodal status |
|||||||||||
| Positive (n= 132) | 47.4 | 72.8 | .031 | 2.06 | 1.07-3.97 | .114 | 1.71 | 0.88-3.35 | .049 | 1.95 | 1.01-3.81 |
| Negative (n= 52) | 74.1 | 77.8 | |||||||||
|
| |||||||||||
| Extrahepatic metastases | |||||||||||
| Yes (n= 16) | 31.5 | 83.9 | .765 | 1.16 | 0.42-3.23 | ||||||
| No (n= 168) | 56 | 73.3 | |||||||||
|
| |||||||||||
| Preoperative chemotherapy |
|||||||||||
| >6 cycles (n= 66) | 42.6 | 63.7 | .022 | 1.82 | 1.09-3.03 | .044 | 1.70 | 1.01 - 2.86 | .088 | 1.57 | 0.93-2.64 |
| ≤6 cycles (n= 118) | 64.5 | 81.4 | |||||||||
|
| |||||||||||
| Multiple CLM | |||||||||||
| Yes (n= 122) | 53.3 | 74.6 | .775 | 1.08 | 0.62-1.88 | ||||||
| No (n= 62) | 60.3 | 73.4 | |||||||||
|
| |||||||||||
| Largest CLM at surgery | |||||||||||
| >5 cm (n= 26) | 48.6 | 61.7 | .199 | 1.54 | 0.80-2.96 | ||||||
| ≤5 cm (n= 158) | 56.4 | 76.5 | |||||||||
|
| |||||||||||
| Positive margin | |||||||||||
| Yes (n= 23) | 65.8 | 76.8 | .959 | 1.02 | 0.44-2.38 | ||||||
| No (n= 161) | 54.6 | 74.4 | |||||||||
|
| |||||||||||
| Pathologic response | |||||||||||
| Minor (n= 84) | 44.6 | 61.5 | .005 | 2.11 | 1.25-3.56 | .033 | 1.78 | 1.05 - 3.03 | - | - | - |
| Major (n= 100) | 64.2 | 85.3 | |||||||||
|
| |||||||||||
| Morphologic response | |||||||||||
| Suboptimal (n= 132) | 49.2 | 68.7 | .007 | 2.78 | 1.31-5.85 | - | - | - | .029 | 2.32 | 1.09-4.97 |
| Optimal (n= 52) | 72.9 | 89 | |||||||||
|
| |||||||||||
| RAS mutational status | |||||||||||
| Mutant (n= 38) | 23.2 | 43.4 | <.001 | 3.57 | 1.99-6.40 | <.001 | 3.25 | 1.80 - 5.87 | <.001 | 3.19 | 1.75-5.78 |
| Wild-type (n= 146) | 61.6 | 81.2 | |||||||||
Abbreviations: HR, hazard ratio; DFI, disease-free interval; CLM, colorectal liver metastasis.
*
In Model 1, all factors except morphologic response were entered in the multivariate analysis. In Model 2, all factors except pathologic response were entered in the multivariate analysis.