Table 5.

Predictive Factors for Tumor Necrosis in Osteosarcoma at 90% Cutoff

Predictive Factors	≥90% Necrosis (%) (n=15)	< 90% Necrosis (%) (n=25)	p value
Tumor change in size			p < 0.01*
Larger	0 (0)	9 (36)
Smaller	11 (73)	2 (8)
No change	4 (27)	14 (56)
Post-chemo tumor size			p < 0.01*
> 10 cm	1 (7)	13 (52)
≤ 10 cm	14 (93)	12 (48)
Post-chemo pain			p = 0.32
Yes	4 (27)	12 (48)
No	11 (73)	13 (52)
Post-chemo ossification			p = 0.02*
Increase	15 (100)	16(64)
No Increase	0 (0)	9 (36)

*Proportions between the two groups are compared using Chi-square test or Fischer exact, p value of ≤ 0.05 is significant.