All the MRI images were acquired using a 1.5 T MRI scanner (SIGNA Explorer, GE Healthcare, Waukesha, WI, USA) with a 16-channel body array coil. To reduce peristaltic artifacts, all the subjects fasted for 6 h and were given intravenous hyoscine butylbromide (Buscopan, Boehringer Ingelheim, Ingelheim am Rhein, Germany) before MRI examinations. Standardized MRI protocol, including conventional T2W, T1W, dynamic contrast-enhanced MRI (DCE-MRI), DWI (b = 0, 400, 800) and synthetic MRI, are summarized in Table 1 .
The image post-processing was performed on a 64-bit Advantage Workstation (GE Healthcare, Waukesha, WI, USA), which generated the parametric maps (T1, T2, PD and ADC), as well as synthetic contrast-weighted images automatically. The mean of the T1/T2/PD/ADC maps were calculated inside the region-of-interest (ROIs) for all slices that contained the tumor.
The image post-processing was performed on a 64-bit Advantage Workstation (GE Healthcare, Waukesha, WI, USA), which generated the parametric maps (T1, T2, PD and ADC), as well as synthetic contrast-weighted images automatically. The mean of the T1/T2/PD/ADC maps were calculated inside the region-of-interest (ROIs) for all slices that contained the tumor.