FIGURE 1.

Heterogeneous tumors in the arterial phase of EOB-MRI have a low AVD and high VETC positivity. (A) Schema of each enhancement pattern. (B) AP-Hetero pattern and AP-Hypo pattern tumors had lower AVD than AP-Homo tumors (Mann-Whitney U test). (C) AP-Hetero tumors had higher VETC positivity than AP-Homo tumors (χ² test). (D) Among VETC⁺ HCCs, regions with VETC had lower AVD than regions without VETC (Wilcoxon signed-rank test). (E) A case of VETC⁺ HCC with AP-Hetero pattern. Strongly enhanced region R1 had no VETC structures but abundant h-caldesmon–positive arteries, whereas weakly enhanced region R2 showed VETC structures but few arteries. Abbreviations: AVD, arterial vessel density; VETC, vessels encapsulating tumor clusters.