Quantitative Evaluation of Hepatic Microstructural Changes in Hepatocellular Carcinoma Using Diffusion Tensor Imaging

Aim: Magnetic resonance imaging (MRI) is a fundamental imaging modality in the diagnosis, management, and follow-up of hepatocellular carcinoma (HCC).Diffusion-based imaging techniques have been shown to potentially play a significant role in the characterization of focal liver lesions.The aim of this study was to evaluate the contribution of diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) in the diagnosis of HCC by comparing DWI and DTI parameters with those of cirrhotic and non-pathological liver parenchyma. Materials and Methods:This retrospective study included 62 patients with HCC, 56 with cirrhosis, and 52 with non-pathological liver parenchyma who underwent 1.5-T MRI.DWI and DTI sequences were acquired using b-values of 50-800 sec/mm 2 and 20 diffusion-encoding directions.Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated and compared across the groups.Results: ADC values were significantly lower and FA values significantly higher in HCC compared to cirrhotic and non-pathological parenchyma (p<0.05).Mean FA was 0.460.14for HCC, 0.390.08 for non-cancerous parenchyma, and 0.400.07for both cirrhotic and non-pathological parenchyma.An FA cut-off of 0.45 yielded 38.7% sensitivity and 94.2% specificity [area under the curve (AUC): 0.653, 95% confidence interval (CI): 0.554-0.751]vs. non-pathological parenchyma, and 62.9% sensitivity and 75.0%specificity (AUC: 0.649, 95% CI: 0.542-0.745)vs. cirrhotic parenchyma. Conclusion:FA values reflected moderate anisotropy in HCC, cirrhotic, and non-pathological liver parenchyma.Although FA differed significantly between HCC and non-malignant tissues, its modest sensitivity limits its utility as a stand-alone biomarker.