TABLE 3.

Final multivariable Cox regression analysis for risk score formation

	HR (95% CI)	p value
Age
<55	Reference	0.007
≥55	1.767 (1.171–2.668)
Primary tumor location
Truncal/extremity	Reference	0.023
Retroperitoneal	1.665 (1.071–2.588)
Primary tumor resection margin
R0	Reference	0.034
R1	1.715 (1.042–2.824)
Tumor grade
Low	Reference	0.132
High	2.237 (0.785–6.373)
# Lung lesions
Single	Reference	0.006
Multiple	1.766 (1.174–2.656)

Note: Bold values indicate statistical significance.

Abbreviations: CI, confidence interval; HR, hazard ratio.