Background: Detection of the value of DCE (dynamic contrast enhanced) MRI and DWI (diffusion-weighted imaging) in follow-up of treatment response for HCC (hepatocellular carcinoma) lesions post TACE (trans-arterial chemo-embolization) through LI-RADS v2018 algorithmic approach. Results: A prospective study was performed on 30 patients with 41 treated hepatic focal lesions. The patients underwent DCE MRI with DWI in less than 1-month duration following TACE procedure and were radiologically assessed to observe tumoral post treatment response; then, another follow-up after another 3 months later was done for non-viable, equivocal, and non-evaluable post treatment response categories. Statistical analysis showed that DCE MRI had 100% level of sensitivity, specificity of 95.24%, PPV of 95.00%, and NPV of 100% with an overall agreement of 97.50%. While on the other hand, statistics showed that DWI has 52.63% level of sensitivity, specificity of 90.48%, PPV of 83.33%, PPV of 67.86%, and NPV of 72.50%. The difference between non-viable and viable groups' ADC variables was found statistically significant at P value < 0.001, and best cut off value that augments sensitivity and specificity is 1.35. At this ADC value, sensitivity reaches 78.9% and specificity is 85.7%. Conclusions:Our study showed that DCE MRI has 100% level of sensitivity via application of LI-RADS v2018 diagnostic algorithmic approach while DWI alone has 52.63% level of sensitivity, yet it can enhance the diagnostic confidence of DCE MRI for post treatment response viability detection.

Background: Hepatocellular Carcinoma (HCC) is the most common primary malignant disease of the liver and is the third leading cause of death from cancer worldwide. Dynamic Contrast-Enhanced MRI (DCE MRI) can play a significant role as an imaging of H.C.C, especially in the detection of viable tumor foci, the differentiation between necrosis and viable tumor after TACE and early prediction of response. Diffusion-weighted MRI shall be more frequently used for tumor response evaluation to TACE because they provide detailed anatomic and functional or metabolic change information during tumor treatment, particularly during targeted chemotherapy. Aim of Study: Detection of the value of DCE (Dynamic contrast enhanced) MRI and DWI (Diffusion Weighted Imaging) in evaluation of HCC (Hepatocellular Carcinoma) necrosis after TACE (Trans-Arterial Chemo-Embolization).Material and Methods: Pre-contrast T1 and T2 WIs followed by diffusion weighted MR images (several b factors 20, 500, 800s/mm 2 ) then DCE MRI study using a 3 Telsa scanner followed by measuring different ADC values obtained in 30 patients underwent TACE for treatment of 40 HCC lesions for assessment of tumoral necrosis. ADC cut-off number was estimated using the ROC curve after measuring ADC values for all cases.Results: Statistical analysis demonstrated that Dynamic MRI had sensitivity of about 100% and 95.24% for specificity, While DWI has level of sensitivity of about 52.63% and 90.5% as a degree of specificity.The difference between well-ablated and residual/newly developed groups'. ADC values was found to be significant statistically ( pvalue <0.001) and best cut-off variable that maximize specificity and sensitivity is 1.35, where sensitivity level reaches about 78.9% and specificity level reaches about 85.7%.Conclusions: Depending on our study, dynamic MRI showed very high sensitivity while DWI with ADC mapping series alone have low level of sensitivity so it promotes reader confidence and might be used in case of gadolinium contraindications or in case of incapability of breath holding adequately.