Clinical Significance of the Transitional Phase at Gadoxetate Disodium–Enhanced Hepatic MRI for the Diagnosis of Hepatocellular Carcinoma

OBJECTIVES: To investigate the clinical significance of the "transitional phase" at gadoxetate disodium (Gd-EOB)-enhanced magnetic resonance imaging for diagnosing hepatocellular carcinoma (HCC). METHODS: We studied 54 patients with 70 histologically diagnosed HCC. Transitional- and hepatobiliary-phase (TP, HBP) images were acquired 3 and 20 minutes after Gd-EOB injection, respectively. Radiologists measured the size of the hepatic tumors on images and surgical specimens and qualitatively evaluated the signal intensity of the hepatic tumors during TP and HBP independently. RESULTS: In 4 patients with portal tumor embolism who had undergone percutaneous transhepatic portal embolization and who manifested arterioportal (AP) shunts, the low-intensity area was larger during HBP than TP. Of the 70 HCCs, 4 were of high signal intensity during HBP and 2 were of slightly low intensity during TP. CONCLUSION: Tumor extension seen during TP rather than HBP more accurately reflected histological findings in patients with HCC with portal tumor thrombi, percutaneous transhepatic portal embolization, or AP shunt.