Hepatocellular carcinoma 20mm or smaller in cirrhosis patients: early magnetic resonance enhancement by gadoxetic acid compared with gadopentetate dimeglumine.

Abstract

To evaluate the differences in enhancement pattern of hepatocellular carcinoma (HCC) 20mm or smaller and enhancement effects of hepatic vessels on early dynamic contrast-enhanced magnetic resonance imaging (MRI) obtained with gadoxetic acid and gadopentetate dimeglumine in the same patients with cirrhosis. We reviewed MR images using gadoxetic acid and gadopentetate dimeglumine in the same 34 patients with 42 histologically confirmed HCCs (median diameter, 14.5mm). The percentage enhancements (PEs) of HCC, the hepatic artery and portal vein and relative contrasts (RCs) between HCC and the liver were calculated and analyzed statistically. The PEs of HCC, the hepatic artery and portal vein were significantly lower for gadoxetic acid in comparison with gadopentetate dimeglumine in the arterial phase (p=0.0256 for HCC, p<0.0001 for hepatic artery) and portal phase (p<0.0001 for HCC, portal vein). The RC between HCC and the liver was significantly lower for gadoxetic acid in comparison with gadopentetate dimeglumine in the arterial phase (p=0.0422), but was not significantly different in the portal phase (p=0.1133). Forty-one of the 42 (97.62%) nodules showed arterial hypervascularization. Of these, 31 (75.61%) nodules were hypointense in the portal phase for gadoxetic acid, and 22 (53.66%) were hypointense for gadopentetate dimeglumine (p=0.038). Compared with gadopentetate dimeglumine, gadoxetic acid-enhanced MRI demonstrated a different enhancement pattern of inferior arterial enhancement and was more rapidly hypointense in the portal phase for HCC. It showed markedly lower enhancement for hepatic artery and portal vein in the patients with cirrhosis.