Abstract
In this report the arterial vascularity within the nodule in small hepatocellular carcinoma (HCC) was evaluated in comparison with histopathological study. For this goal, dynamic contrast-enhanced ultrasonography with intraarterial CO2 microbubbles infusion (US angiography) was performed on 39 patients with surgically resected 44 small HCCs smaller than 3cm in diameter.
The results are as follows:
1) Out of 44 HCCs, 35 were demonstrated as hypervascular, 5 as isovascular, 3 as vascular spot in hypovascular, and 1 as hypovascular.
2) Out of 11 HCCs, which were pathologically classified into Grade I on Edmondson-Steiner scale, 4 were demonstrated as isovascular, 6 were demonstrated as hypervascular, and 1 were demonstrated as hypovascular.
3) Almost all GradeII-III HCCs (29/30) were demonstrated as hypervascular.
4) Out of 13 angiographically undetected HCCs, 4 were isovascular nodules, 3 were hypovascular nodules including vascular lesions, 5 were hypervascular nodules, and 1 was hypovascular nodule.
5) Out of 13 angiographically undetected HCCs, 9 nodules including 2 hypervascular nodules were nonencapusulated HCCs on pathological study of the resected specimen.
6) Sensitivity in demonstrating hypervascularity of the HCC improved to 80% (35/44) by the use of US angiography, compared to 70% (31/44) with conventional angiography or 73% (30/41) with Lipiodol CT. Moreover, sensitivity in evaluating tumor vascularity with US angiography was 100% (44/44).
Our conclusions based on these results are as follow:
1) All HCCs except one have arterial vascularity within the tumor.
2) Half of well-differentiated HCC exhibited isovascualr or hypovascular, suggesting immature neovascularization within the tumor.
3) Tumors undetected with angiography or Lipiodol CT are isovascular, non-encapsulated, or considerably small HCCs.
4) US angiography is sensitive in the detection of arterial vascularity within the HCC nodules, and hence, contributory to the diagnosis of small HCCs.
