Table 5.

These are all of the variables from Tables 1 and 2 where the univariate P-value was significant at P≤ 0.10

Overall survival	HR (95% CI)	P value
Univariate analysis
Increasing interval (per year) from primary resection to hepatic metastases	1.11 (1.04–1.18)	0.003
Synchronous disease at diagnosis	0.55 (0.30–1.01)	0.05
Increasing length of stay (per day)	1.06 (1.00–1.12)	0.04
Primary site
Pancreas	0.53 (0.24–1.13)	0.10
Lung/thymus	5.69 (1.86–17.43)	0.002
Rectum	4.76 (1.07–21.24)	0.04
Primary procedure
Partial hepatectomy	0.11 (0.01–0.91)	0.04
Segmentectomy	0.37 (0.12–1.15)	0.09
RFA	0.35 (0.11–1.09)	0.07
Post-operative complications
Fluid collection	3.83 (0.89–16.48)	0.07
Hepatic	9.88 (2.13–45.88)	0.004
Multivariate analysis
Increasing interval from primary resection to hepatic metastases	1.11 (1.02–1.20)	0.01
Primary site
Lung/thymus	15.63 (4.30–56.8)	0.002
Post operative complications
Fluid collection	15.89 (3.10–81.4)	0.0009
Hepatic	22.94 (4.39–120.0)	0.0002

These univariate variables were entered into a multivariate, saturated model utilizing backward elimination to remove the insignificant variables (P > 0.05) in a multiple regression analysis. Interestingly, margin status (R0 vs. R1 vs. R2) and primary procedure did not meet the criteria to be included in the multivariate model (i.e. P > 0.05).