Table 3 Clinicopathological factors associated with overall survival based on univariate Cox proportional regression analysis

Sex

Female

25

1

0.837

Male

28

1.064

0.590–1.919

Age

≥ 20 years

18

1

0.777

< 20 years

35

1.093

0.591–2.022

Tumor size

< 5 cm

27

1

0.940

≥ 5 cm

26

1.024

0.556–1.884

Histologic grade*

I

15

1

0.412

II

25

1.267

0.634–2.534

0.503

III

13

1.738

0.771–3.917

0.183

Distant metastasis*

Yes

23

1

< 0.001

No

30

0.161

0.073–0.356

Enneking staging*

I

12

1

< 0.001

II

19

8.605

2.942–25.169

III

22

26.039

7.679–88.293

TfR1*

Low

11

1

< 0.001

Moderate

19

0.158

0.063–0.398

High

23

0.300

0.143–0.629

VEGF*

Low

10

1

0.021

Moderate

19

0.114

0.043–0.303

High

24

0.422

0.202–0.880