Prognostic Factors and a Nomogram Predicting Overall Survival in Patients with Limb Chondrosarcomas: A Population-Based Study

Table 2

Univariate Cox regression analysis in the training group.

Variable	HR	Univariate analysis	value
		95% CI
Age
<40 years	Ref
40-59 years	2.81	1.48-5.57	0.003
≥60 years	7.23	3.72-14.05	<0.001
Race
White	Ref
Black	0.46	0.19-1.12	0.09
Other	0.63	0.26-1.54	0.31
Sex
Male	Ref
Female	0.85	0.60-1.23	0.41
Site
LU	Ref
SU	0.73	0.18-3.06	0.67
LL	1.70	1.13-2.56	0.01
SL	0.96	0.37-2.46	0.93
Histology
Conventional	Ref
Myxoid	1.72	0.74-3.95	0.21
Dedifferentiated	9.54	6.57-13.87	<0.001
Grade
Grade I	Ref
Grade II	2.32	1.29-4.15	0.005
Grade III	5.82	3.18-10.63	<0.001
Grade IV	13.68	7.63-24.52	<0.001
Laterality
Left	Ref
Right	1.02	0.72-1.45	0.389
Stage
Localized	Ref
Regional	3.67	2.40-5.59	<0.001
Distant	14.97	9.28-24.11	<0.001
Surgery performed
No	Ref
Yes	0.46	0.26-0.82	0.008
Total number of tumors
	Ref
	0.89	0.48-1.65	0.70
Radiation
No	Ref
Yes	3.71	2.22-6.19	<0.001
Chemotherapy
No	Ref
Yes	4.31	2.80-6.62	<0.001
Tumor size
<8 cm	Ref
8-13 cm	2.72	1.75-4.23	<0.001
≥13 cm	4.43	2.91-6.73	<0.001

Note: HR: hazard ratio; CI: confidence intervals; LU: long bones: upper limb, scapula, and associated joints; SU: short bones: upper limb, scapula, and associated joints; LL: long bones of lower limb and associated joints; SL: short bones of lower limb and associated joints.