Table 3. Correlation between Tumor Necrosis Rate and Diffusion-Weighted MRI Parameters.

Variable	r	P
Mdpre (x 10-3 mm2/s)	0.171	0.375
MKpre	-0.197	0.306
ADCpre (x 10-3 mm2/s)	0.283	0.137
Tumor volumepre (cm3)	-0.119	0.540
Mdpost (x 10-3 mm2/s)*	0.669	< 0.001
Mkpost	-0.294	0.121
ADCpost (x 10-3 mm2/s)	0.462	0.012
Tumor volumepost (cm3)	-0.193	0.316
ΔMD*	0.622	< 0.001
ΔMK	-0.261	0.171
ΔADC	0.447	0.015
ΔTumor volume	-0.197	0.306

^*High correlation (r > 0.6) is demonstrated at 0.005 level (2-tailed). ΔX = change ratio