Table 3. Multivariate Model of Overall Survival for All Subjects.
| Variable | Univariate HR |
95% CI | Pe | Multivariate HR |
95% CI | Pf |
|---|---|---|---|---|---|---|
| Age (per 5 years) a | 0.88 | 0.77 to 1.00 | 0.053 | 0.88 | 0.77 to 1.01 | 0.063 |
|
| ||||||
| Sex | ||||||
| Female | 1.00 (ref) | -- | -- | 1.00 (ref) | -- | -- |
| Male | 1.77 | 1.00 to 1.77 | 0.049 | --b | -- | 0.63 |
|
| ||||||
| KRAS status | ||||||
| Wild type | 1.00 (ref) | -- | -- | 1.00 (ref) | -- | -- |
| Mutant | 0.89 | 0.52 to 1.54 | 0.683 | 0.88 | 0.46 to 1.68 | 0.69 |
|
| ||||||
|
Stratified site(s) of
metastasis |
0.0002c | |||||
| Liver only | 1.00 (ref) | -- | -- | 1.00 (ref) | -- | -- |
| Peritoneum only | 8.24 | 2.67 to 25.39 | 0.0002 d | 18.33 | 5.36 to 62.77 | < 0.0001 |
| Liver or peritoneum plus another site |
3.49 | 1.69 to 7.22 | 0.0008 d | 3.45 | 1.58 to 7.56 | 0.002 |
| Liver and peritoneum not involved |
1.70 | 0.67 to 4.32 | 0.261 d | 1.93 | 0.69 to 5.38 | 0.21 |
|
| ||||||
|
Count of liver lesions
(per 5 lesions) a |
1.11 | 1.05 to 1.17 | 0.0003 | 1.16 | 1.09 to 1.23 | < 0.0001 |
|
| ||||||
|
Count of retroperitoneal
adenopathy (per node) a |
1.11 | 1.03 to 1.19 | 0.008 | 1.09 | 0.99 to 1.10 | 0.069 |
|
| ||||||
|
Count of peritoneal lesions(per lesion) a |
1.15 | 1.05 to 1.26 | 0.0027 | --b | -- | 0.71 |
a
Hazard ratios for continuous variables are per unit change with unit listed in parentheses. The unit of change in the liver was chosen as five lesions to better reflect the clinical scale of the effect in this organ, where larger counts were more common. The per-lesion multivariate HR for the liver was 1.02.
b
Sex and count of peritoneal lesions were eliminated in stepwise selection for the multivariate model.
c
Test for equality over all strata.
d
Pairwise comparisons were made with respect to the reference stratum.
e
Log-rank test.
f
Wald chi-square statistic from Cox proportional hazards model.