Role of ADC mapping in assessment of therapeutic response of hepatocellular carcinoma post trans-catheter arterial chemoembolization

Abstract

HCC is the fifth most common cancer worldwide, and has a poor prognosis unless treated. Ablative therapies are promising treatment option for patients with liver tumors who are not eligible for surgery. Monitoring tumor response after trans-arterial chemoembolization(TACE)is an increasingly important task in oncologic imaging. Early favorable response indicates effectiveness of therapy while early identification of treatment failure is also critical in patient management as further treatment will be mandatory before disease progression. Recent advances in the development of functional MRI techniques have provided the ability to detect microscopic changes in tumor microenvironment and microstructure that allow better assessment of treatment response. DCE- MRI can assess the change in the tumor vascularity and perfusion. While DWI/ADC is used in the quantification of hepatic fibrosis in chronic liver disease in characterization and detection of focal liver lesions. ADC maps and average value can be used as a quantitative value to differentiate between active and inactive tumors and in monitoring response to treatment in oncological patients.