Prediction of poorly differentiated hepatocellular carcinoma using contrast computed tomography

Abstract

Background: Percutaneous radiofrequency ablation (RFA) is a well-established local treatment for small hepatocellular carcinoma (HCC). However, poor differentiation is a risk factor for tumor seeding or intrahepatic dissemination after RFA for HCC. The present study aimed to develop a method for predicting poorly differentiated HCC using contrast computed tomography (CT) for safe and effective RFA. Methods: Of HCCs diagnosed histologically, 223 patients with 226 HCCs showing tumor enhancement on contrast CT were analyzed. The tumor enhancement pattern was classified into two categories, with and without non-enhanced areas, and tumor stain that disappeared during the venous or equilibrium phase with the tumor becoming hypodense was categorized as positive for washout. Results: The 226 HCCs were evaluated as well differentiated (w-) in 56, moderately differentiated (m-) in 137, and poorly differentiated (p-) in 33. The proportions of small HCCs (3 cm or less) in w-HCCs, m-HCCs, and p-HCCs were 86% (48/56), 59% (81/137), and 48% (16/33), respectively. The percentage with heterogeneous enhancement in all HCCs was 13% in w-HCCs, 29% in m-HCCs, and 85% in p-HCCs. The percentage with tumor stain washout in the venous phase was 29% in w-HCCs, 63% in m-HCCs, and 94% in p-HCCs. The percentage with heterogeneous enhancement in small HCCs was 10% in w-HCCs, 10% in m-HCCs, and 75% in p-HCCs. The percentage with tumor stain washout in the venous phase in small HCCs was 23% in w-HCCs, 58% in m-HCCs, and 100% in p-HCCs. Significant correlations were seen for each factor (p∈