Characteristics of Hypovascular versus Hypervascular Well-Differentiated Hepatocellular Carcinoma Smaller Than 2 cm - Focus on Tumor Size, Markers and Imaging Detectability.

Objectives: The characteristics of hypovascular and hypervascular well-differentiated hepatocellular carcinomas (HCCs) were compared in terms of tumor size, tumor markers and detectability by imaging modalities.

Methods: Well-differentiated HCC nodules that are smaller than 2 cm (n = 27) were evaluated in 27 patients using histopathology and divided into 2 groups: hypovascular (n = 10) and hypervascular (n = 17). The diagnostic sensitivity of imaging modalities was then evaluated for efficiency in disclosing tumor size and tumor markers in the 2 types.

Results: No difference was observed in tumor size and tumor markers between the 2 types; however, the sensitivity of contrast-enhanced CT, contrast-enhanced ultrasonography and arterioportal angiography was significantly different between the 2 types, whereas that by Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid enhanced magnetic resonance imaging (Gd-EOB-DTPA MRI) demonstrated no difference.

Conclusion: Hypovascular HCC could be diagnosed by Gd-EOB-DTPA MRI in the hepatobiliary phase.