Doughnut-like hyperintense nodules on hepatobiliary phase without arterial-phase hyperenhancement in cirrhotic liver: imaging and clinicopathological features

Objectives To determine the imaging and clinicopathological features of MRI doughnut-like nodules (HBP-doughnut nodules), hyperintense at the hepatobiliary phase (HBP) after injection of gadoxetic acid (EOB) and without arterial-phase hyperenhancement (APHE) in cirrhotic liver. Methods The Institutional Review Board approved this retrospective study and informed consent was waived. We enrolled 309 consecutive patients with liver cirrhosis who were examined by EOB-MRI, dynamic CT, and angiography-assisted CT between 2008 and 2012 and searched for HBP-doughnut nodules. We evaluated imaging characteristics including haemodynamics and signal intensity of MRI, pathological findings, and frequency of malignant transformation. Results One hundred and one HBP-doughnut nodules without APHE were identified in 18 patients (6%), including seven of 59 (12%) patients with hepatitis-B-virus-related, nine of 230 (3.9%) with hepatitis-C-virus-related, and two of 33 (6.1%) with alcoholic cirrhosis. All nodules showed enhancement peaks in the portal phase, the same or increased intranodular portal supply on CT during arterial portography, and the same or decreased intranodular arterial supply on CT during hepatic arteriography. On T2-weighted and diffusion-weighted images, 37 (36%) and 24 (24%) nodules, respectively, showed hyperintensity predominantly in the central area. Three nodules were diagnosed by fine needle biopsy as non-neoplastic hepatic nodules. Ninety-three of 101 (92%) nodules in 16 patients were followed up during an observation period of 1163 ± 902 days (range 57–2920 days), and none showed malignant transformation. Conclusion HBP-doughnut nodules without APHE in cirrhotic liver were not infrequent. None became malignant. We propose calling them ‘multiacinar cirrhotic nodules’ based on the classification by an International Working Party. Key Points • HBP-doughnut nodules without APHE were seen in 6% of patients with liver cirrhosis. • The enhancement peak of HBP-doughnut nodules without APHE was in the portal phase, which reflected the fact that they were supplied predominantly by the portal vein, based on angiography-assisted CT findings. • None of the HBP-doughnut nodules without APHE in cirrhotic liver became malignant, and in conjunction with limited pathological features, they may be corresponding to multiacinar cirrhotic nodules in the International Working Party classification.