Background: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and has a poor prognosis unless treated. The aim of this work was to assess HCC cases after transarterial chemoembolization by subtraction dynamic contrast enhanced MRI to detect its accuracy, sensitivity and specificity in detecting residual tumor and assess the need for further treatment. Methods: 35 patients with 42 HCC lesions underwent transarterial chemoembolization were included in this study. Those patients underwent MRI after 3 months where dynamic MRI and subtraction dynamic MRI were obtained. The interpretation of dynamic MRI and the subtraction dynamic MRI was done by two different readers experienced in hepatic imaging blinded to each other. Patients were classified according to reactivity rate into 2 independent groups: Reactive group (30 patients), Not reactive group (5 patients). Results: Comparative study between D-MRIand DS-MRI assessments revealed; highly significant increase in reactivity rate in DS-MRI in HCC patients during 1 st and 2 nd readings; with highly significant difference (p = 0.0078 respectively). By using ROC-curve analysis, DS-MRI assessment discriminated patients with reactivity from patients without, with perfect accuracy, sensitivity= 100% and specificity= 100% (p < 0.0001). Conclusion: Dynamic MRI is valuable in detecting recurrent lesions however, this value is augmented by the addition of subtraction technique especially in lesions having high signal before administration of contrast medium.

Background: Hepatocellular carcinoma (HCC) accounted as the sixth most prevalent cancer worldwide and the third most common cancer leading to death. However unfortunately only a minority HCC patients are surgical candidates at the time of diagnosis, Transcatheter arterial chemoembolization (TACE) is one of the most commonly used intra-arterial therapies to treat unresectable HCC, Assessing early response to therapy using objective criteria is paramount for clinical care.