Factors predicting aggressiveness of non-hypervascular hepatic nodules detected on hepatobiliary phase of gadolinium ethoxybenzyl diethylene-triamine-pentaacetic-acid magnetic resonance imaging

Figure 3 Size distribution over time and representative microscopic images of non-hypervascular nodules that progressed without hypervascularity. A: The median diameter of 73 non-hypervascular nodules (NHNs) was 9 mm [interquartile range (IQR): 8-12 mm] at the first detection. Diameter was plotted against time to show their growth/reduction rate during the study period. NHNs were classified into 3 groups based on vascularity and size changes in the observation period: hypervascular, enlarged and reduced groups. In the hypervascular group, the vascularity in the arterial phase was confirmed at the endpoint in each case. NHNs in the enlarged group grew at least 2 mm in diameter by the end of the observation, while the diameter decreased 2 mm or more in the reduced group; B: Tissue samples were obtained from 6 of 58 progressed NHNs. Most specimens show thick (1: case #21-1 allocated in supplementary Table 1) or thin (2: case #19-5 allocated in supplementary Table 1) trabecular patterns of tumor cells with nuclear crowding and hypercellularity, which were diagnosed as well-differentiated hepatocellular carcinoma (HCC). One specimen (3: case #22-1 allocated in supplementary Table 1) shows less-differentiated tumor cells with a vacuolated appearance and nuclear irregularity; it was diagnosed as moderately differentiated HCC. (H and E: Each scale bar represents 50 μm.)