Dynamic (gadolinium-enhanced) subtraction MRI of large hepatocellular carcinoma before and after transarterial chemoembolization (TACE)

(A) Pre-treatment axial gadolinium-enhanced arterial phase MRI of a 60-year-old male showing a large enhancing lesion in segment 6 of liver (arrow).
(B) There is evidence of washout in the portal venous phase.
(C) Subtraction MRI showing enhancement (arrow). To obtain the subtracted image, pre-contrast T1 weighted image is subtracted from post-contrast T1 weighted image.
(D) Axial post-contrast MRI at the same level four weeks after chemoembolization showing no enhancement and minimal change in size. This is consistent with a CR according to modified RECIST for hepatocellular carcinoma (mRECIST) but stable disease by standard RECIST criteria.