Table 3.

Multivariate analysis of OS with significant disease-related variables on univariate analysis.

Variablea	P value	HR	95% CI
CEA levels before RE (≥90 vs. <90)	0.004	3.0	1.4-6.2
Lymphovascular invasion on pathology of primary	0.002	3.3	1.6-6.9

^aVariables entered: (1) Lymphovascular invasion of primary, (2) CEA levels ≥90 ng/mL, (3) Synchronous disease and (4) >25% liver replacement by tumor at time of RE. Forward model selection was performed using the Wald test as the criterion. The final model included the first two variables, confirming these as independent predictors of OS.

Note: The variable time from diagnosis of CRC to CLM was considered similar to the variable indicating presence or not of synchronous disease and thus was not entered in the multivariate model despite displaying statistical significance in univariate analysis. The variable bilobar disease vs. unilobar disease in patients with two hepatic lobes was not entered in the multivariate model in order to not exclude the seven patients with unilobar disease within one surgical lobe from analysis. The variable ≥3 vs. <3 sites of extrahepatic disease was not entered since the presence of extrahepatic disease was not statistically significant in univariate analysis.