Fig. 20.

Expected treatment response after transarterial bland embolization (TAE) and drug-eluting beads transarterial chemoembolization (DEB-TACE). Axial contrast-enhanced CT images of the liver obtained in late arterial phase are illustrated: a Pretreatment: typically used for bridging, debulking, or palliative treatment in patients with intermediate-stage hepatocellular carcinoma without vascular invasion. May be used alone or in combination with other treatments. b 1–3 months posttreatment: TAE and DEB-TACE show similar posttreatment evolution since drug-eluting beads are not visible on imaging. Contrary to TACE, since no hyperdense ethiodized oil is used, tumor viability is easier to assess on CT. The same following features as TACE may be seen: thin uniform rim enhancement around the treated zone, regional parenchymal enhancement, and intratumoral gas foci (up to 4–6 weeks posttreatment). c ≥ 6 months posttreatment: size of necrotic zone decreases over time. Regional parenchymal enhancement resolves. Rim enhancement along the treated zone may persist for months to years. At any point posttreatment, presence of nodular arterial phase hyperenhancement, washout appearance, or enhancement similar to pretreatment indicates recurrence or residual viable tumor