The purpose of this study is to determine the whether Lipiodol can be used as an imaging biomarker, predicting tumor response to therapy in patients with primary and metastatic liver cancer. Lipiodol-based transarterial chemoembolization (TACE) has been an accepted standard of care procedure for unresectable liver lesions for several decades. Lipiodol is used as a carrier for chemotherapy agents and also as an occlusion agent. In TACE procedures, Lipiodol is mixed with the chemotherapy agent(s) and delivered to the tumor via the hepatic artery, causing necrosis of the targeted tumor(s). Response to therapy will be evaluated every 1, 3 and 6 months by clinic visits, MRI/CT/PET scans and blood tests (to include assessment of liver function and tumor markers).