Differentiation of early hepatocellular carcinoma from benign hepatocellular nodules on gadoxetic acid-enhanced magnetic resonance imaging

Abstract

Objective: To propose new diagnostic criteria for the discrimination of early hepatocellular carcinoma (HCC) from benign hepatocellular nodules on gadoxetic acid-enhanced magnetic resonance imaging (MRI).Materials and methods: I analyzed 34 patients with surgically-diagnosed 29 early HCCs and 31 benign hepatocellular nodules. Two radiologists reviewed the gadoxetic acid-enhanced MRI including diffusion-weighted imaging (DWI), and the signal intensity at each sequence, presence of arterial enhancement and washout were recorded. I composed new diagnostic criteria based on the lesion size and MRI findings, and then the diagnostic performance was compared with that of conventional imaging criteria with logistic regression and a generalized estimating equation method.Results: A size cut-off value (≥1.5cm) and MRI findings of T1 hypointensity, T2 hyperintensity, DWI hyperintensity, arterial enhancement, late washout, and hepatobiliary hypointensity were selected as the diagnostic criteria. When the lesion satisfied three or more findings were considered malignant, the sensitivity was significantly higher than the diagnosis based on arterial enhancement and washout alone (58.6% vs. 13.8%, respectively, p=0.0002), while the specificity was 100.0% for both criteria.Conclusions: Tne new diagnostic criteria on gadoxetic acid-enhanced MRI in this study may help to improve the discrimination of early HCC from benign hepatocellular nodules.