Table 4. Imaging Diagnosis of Probable HCC.

Diagnostic Criteria for Probable HCC
In nodules ≥ 1 cm that do not meet the major imaging features of HCC, a diagnosis of “probable” HCC can be assigned by applying ancillary imaging features: 1) nodule without APHE: at least one each of the ancillary features of group A and group B; 2) nodule with APHE but without washout appearance: at least one of the ancillary features in group A or B.
These criteria should be applied only to a lesion that does not show either marked T2 hyperintensity or targetoid appearances on diffusion-weighted images or contrast-enhanced images.
Ancillary Imaging Features of HCC
Ancillary features suggesting malignancy in general (group A)	Ancillary features favoring HCC in particular (group B)
·Mild-to-moderate T2 hyperintensity	·Enhancing or non-enhancing capsule
·High signal intensity on diffusion-weighted imaging	·Mosaic architecture
·Threshold growth*	·Nodule-in-nodule

^*Threshold growth is defined as a size growth of the nodule of at least 50% in the longest dimension in ≤ 6 months on computed tomography or magnetic resonance imaging [165]. HCC = hepatocellular carcinoma, APHE = arterial phase hyperenhancement