Data calculation and analysis

The solid component of each tumor was recognized on T2WI and postcontrast T1WI and was then matched on ADC maps. The ADC values of the solid components of each lesion was measured on diffusion weighted images by one radiologist with the manufacturer’s software (FuncTool; GE, Medical Systems, Milwaukee, WI, USA) at an Advantage Windows workstation 4.2 (GE Healthcare). In order to balance variability and error, the largest possible regions of interest (ROIs) ranging from 15 to 500 mm² were manually placed in the solid portions of the tumors and the degenerative regions were avoided to the best of our ability. No more than three ROIs were drawn in each lesion, and the mean ADC values were calculated and used in our study.