Table 1 Demographic and clinical characteristics of the included patients

Age (year)

  ≤ 18

57 (49.6%)

11 (52.4%)

39 (58.2%)

1.367

0.850

 19–40

43 (37.4%)

7 (33.3%)

21 (31.3%)

  ≥ 41

15 (13.0%)

3 (14.3%)

7 (10.4%)

Gender

 Male

64 (55.7%)

13 (61.9%)

44 (65.7%)

1.817

0.403

 Female

51 (44.3%)

8 (38.1%)

23 (34.3%)

Tumor site

 Upper limb

12 (10.4%)

4 (19.0%)

9 (13.4%)

4.218

0.377

 Lower limb

100 (87.0%)

15 (71.4%)

54 (80.4%)

 Spine-pelvis

3 (2.6%)

2 (9.5%)

4 (6.0%)

Stage T

 T1

43 (37.4%)

7 (33.3%)

23 (36.0%)

7.873

0.248

 T2

68 (59.1%)

12 (57.1%)

42 (60.1%)

 T3

1 (0.9%)

2 (9.5%)

1 (2.0%)

 Unknown

3 (2.6%)

0 (0%)

1 (2.0%)

Stage N

 N0

81 (70.4%)

14 (66.7%)

44 (65.7%)

8.405

0.078

 N1

0 (0%)

0 (0%)

4 (6.0%)

 Unknown

34 (29.6%)

7 (33.3%)

19 (28.4%)

Bone Mets

 No

100 (87.0%)

13 (61.9%)

46 (68.7%)

12.071

0.002

 Yes

15 (13.0%)

8 (38.1%)

21 (31.3%)

Surgery

 No

7 (6.1%)

10 (47.6%)

3 (4.5%)

47.557

 < 0.001

 Salvage

64 (55.7%)

5 (23.8%)

31 (46.3%)

 Amputation

31 (27.0%)

4 (19.0%)

31 (46.3%)

 Unknown

13 (11.3%)

2 (9.5%)

2 (3.0%)

Chemotherapy

 No

0 (0%)

3 (15.0%)

0 (0%)

31.355

 < 0.001

 Yes

87 (86.1%)

16 (80.0%)

64 (97.0%)

 Unknown

14 (13.9%)

1 (5.0%)

2 (3.0%)

Necrosis

  < 90%

26 (22.6%)

5 (23.8%)

34 (50.7%)

26.393

 < 0.001

  ≥ 90%

27 (23.5%)

0 (0%)

4 (6.0%)

 Unknown

62 (53.9%)

16 (76.2%)

29 (43.3%)

Ki-67

  < 50%

35 (30.4%)

3 (14.3%)

8 (11.9%)

9.617

0.047

  ≥ 50%

12 (10.4%)

2 (9.5%)

10 (14.9%)

 Unknown

68 (59.1%)

16 (76.2%)

49 (73.1%)

LDH

 Normal

89 (77.4%)

13 (61.9%)

41 (61.2%)

6.155

0.046

 Elevated

26 (22.6%)

8 (38.1%)

26 (38.8%)

ALP

 Normal

44 (38.3%)

8 (38.1%)

19 (28.4%)

6.172

0.187

 Within one time

40 (34.8%)

6 (28.6%)

18 (26.9%)

 More than two times

31 (27.0%)

7 (33.3%)

30 (44.8%)