Abstract: Objective   To explore the value of apparent diffusion coefficient (ADC) in the grading of hepatocellular carcinoma (HCC). Methods   MR images of 92 patients with HCC proved by histology were reviewed. All patients were performed plain and enhanced MRI and DWI. The ADC values were calculated, the difference of the ADC values of HCC with different grade and the relationship of ADC value and the differentiation were evaluated, respectively. Results    The mean ADC value of the poorly-differentiated HCC (0.9 ± 0.13×10-3 mm2/s) was lower than those of the well-differentiated HCCs (1.263±0.388×10-3mm2/s) (p< 0.05) and moderately-differentiated HCC (1.072±0.227×10-3mm2/s) (p<0.05). There was a negative correlation between the differentiation and the ADC value of the HCC (r = -0.404, p=0.0001). Conclusion   ADC value plays an important role in the preoperative grading of HCC.

Key words: Carcinoma, Hepatocellular, apparent diffusion coefficient, diagnosis