Table 1 Treatment response features. Reprinted, with permission, from ACR [5]
From: Assessment of hepatocellular carcinoma treatment response with LI-RADS: a pictorial review
Features | Definitions |
|---|---|
Viability | Presence of live tumor cells within or along the margin of a treated lesion. Radiologic viability is not synonymous with pathologic viability as imaging is not sensitive to microscopic or small foci of residual tumor. |
Treatment-specific expected enhancement
| Expected temporal and spatial pattern of posttreatment enhancement attributable to treatment-related changes in parenchymal perfusion. Posttreatment enhancement patterns may not reliably differentiate viable from nonviable tumor. The most appropriate response category may be LR-TR Equivocal. |
No lesional enhancement
| Absence of enhancement within or along the margin of a treated lesion. Note: complete disappearance after locoregional treatment is considered equivalent to absence of enhancement. |
Posttreatment APHE
| Nodular, masslike, or thick and irregular arterial phase hyperenhancement (APHE) contained within or along the margin of a treated lesion suggests posttreatment tumor viability. |
Posttreatment “washout”
| Nodular, masslike, or thick and irregular washout appearance contained within or along the margin of a treated lesion suggests posttreatment tumor viability. |
Posttreatment enhancement similar to pretreatment
| Nodular, masslike, or thick and irregular enhancement similar to pretreatment enhancement in all postcontrast phases contained within or along the margin of a treated lesion suggests posttreatment tumor viability, even in the absence of APHE or washout appearance. |
