[Three cases of hepatocellular carcinoma with nodules showing different signal intensities in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI].

We report three cases of resected hepatocellular carcinomas with nodules showing different signal intensities in the hepatobiliary phase of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MRI (EOB-MRI). One case involved a nodule-in-nodule type hepatocellular carcinoma that showed high signal intensity for the outer tumor and low intensity for the inner tumor in the hepatobiliary phase of EOB-MRI. The inner tumor was more dedifferentiated than the outer. The other two cases involved similar nodules, which showed different signal intensities in the hepatobiliary phase of EOB-MRI. In all three cases, the expression of OATP8 showed good correlation with high signal intensity in the hepatobiliary phase of EOB-MRI, whereas MRP2, MRP3, or both were also highly expressed. However, in the two nodules showing low intensities, the expression of one excreting transporter was independently high even though that of OATP8 was not high. The expression of excreting transporters is usually characterized by passive correspondence to OATP8 expression levels; nevertheless, it sometimes shows expression independent of OATP8.