Apparent diffusion coefficient and dynamic contrast-enhanced MRI as reliable biomarkers for evaluating response to locoregional therapy in hepatocellular carcinoma patients

Aim of this study: To evaluate the diagnostic utility of DW-MRI with ADC and colored maps, as well as DCE-MRI with subtraction and perfusion color-coded maps for evaluation of the tumor response after LRT in patients with HCC. Patients and methods: 56 patients with 74 pathologically proven HCC lesions, treated with LRTs (TACE or RFA), were enrolled in this study. They were subjected to multi-parametric functional MRI with semi-quantitative postprocessing tools, initially and 4 follow-ups over one year. This protocol consisted of non contrast MRI sequences including the DW-MRI with quantitative ADC and colored maps, as well as the DCE-MRI with digital subtraction and semi-quantitative color-coded perfusion maps. Results: The DW-MRI (with ADC data and colored maps) showed low accuracy (94.87%) and specificity (92.90%), but high sensitivity (98.96%). The DCE-MRI (with digital subtraction and color-coded perfusion maps) yielded very high accuracy (98.06%), specificity (100%). and sensitivity (98.65%). The combined use of both sequences revealed 100% sensitivity, 100% specificity, and 99.09% accuracy. Conclusion: The use of DW-MRI (with ADC data and colored maps) and the DCE-MRI (with digital subtraction and color-coded perfusion maps) can be considered as in-vivo digital biomarkers for evaluating the response to LRT in patients with HCC.