Fig. 2.

Flowchart summarizing interpretation of imaging findings. An avascular treatment site, or the presence of treatment specific enhancement, was defined as negative for tumor recurrence on both modalities (equivalent to LR-TR Non-Viable). The presence of a nodular region of arterial phase hyperenhancement (APHE) that demonstrates washout on portal venous or delayed phase images was defined as positive for tumor recurrence on both modalities (equivalent to LR-TR Viable). An isolated finding of APHE only or washout only, on either modality, was defined as equivocal for tumor recurrence (equivalent to LR-TR Equivocal). Equivocal findings were further evaluated with the alternative modality. An avascular treatment site or treatment specific enhancement on the alternate modality was then defined as negative for tumor recurrence. APHE with washout, APHE only, or washout only, seen on the alternate modality (and corresponding to the equivocal finding on the first modality) was then defined as positive for tumor recurrence