Table 5.

Multivariate analysis of factors associated with overall survival in osteosarcoma with inclusion of IMPDH2/HPRT ratio.

Factor	Overall survival
	HR (95% CI)	P value
Age at diagnosis (years)
≤ 15	1.00	–
> 15	1.36 (0.83–2.23)	0.216
Site
Extremities	1.00	–
Axial	0.92 (0.43–1.97)	0.841
Stage
IIB	1.00	–
III	2.38 (1.45–3.91)	0.001
Treatment completion
Completed	1.00	–
Not completed	3.03 (1.85–4.97)	< 0.001
IMPDH2/HPRT ratio
Low	1.00	–
High	1.67 (1.02–2.72)	0.039