Review Article

MR Imaging of Hepatocellular Adenomas and Differential Diagnosis Dilemma

Table 1

Hypervascular lesions in noncirrhotic patients. The most important elements to achieve the differential diagnosis.

MRI features
Risk factor and clinical settingT2wT1w inT1w outDWIPre-cArtP PVP EqP HBP Specific pattern

Inflammatory adenoma Hyper Hypo Hypo Restriction Hypo Hyper + Hyper Hyper/iso Hypo/hyper Signal heterogeneity, hypervascularity, intralesional hemorrhage
HNF-1α-mutated adenomaObesity, steatosis, diabetes, glycogenesis, exogenous steroids Iso/hyperHyperHypoNo restriction Iso/hypoHyper Hypo Hypo Hypo Fatty intralesional component
β-catenin-mutated adenomaHyperHypoHypoRestrictionHypoHyper + Hyper Hyper/iso Hypo/hyper Intralesional hemorrhage, necrosis
Unclassified adenoma Nonspecific patterns reported
Focal nodular hyperplasia Exogenous steroids Iso Iso Iso No restriction Iso Hyper +++ Iso Iso Iso/hyper Signal homogeneity, hypervascularity, scar, iso/hyperintensity on HbP
Large regenerative nodule Myeloproliferative and lymphoproliferative disorders, chronic vascular and rheumatologic syndromesIso Iso Iso No restriction Iso Hyper ++ Iso Iso Iso/hyper Multiple lesions signal homogeneity, hypervascularity, scar, isohyperintensity on HbP
HCC in noncirrhotic liver and FL-HCCExogenous steroidenvironmental and dietary factors (aflatoxins and nitrosamine)Hyper Hypo Hypo Restriction Hypo Hyper ++ Hypo Hypo Hypo Signal heterogeneity, intralesional hemorrhage, signs of malignancy
Cholangiocarcinoma Viral hepatic infection Hyper Hypo Hypo Restriction Hypo Hyper Hypo Hypo/iso Hypo/hyper Peripheral enhancement, peripheral washout, central pooling, signs of malignancy
Primary lymphoma Epstein-Barr infection (EBV), HBV and/or HCV infectionsIso/hyper Hypo Hypo Restriction Hypo Hyper Hypo Hypo Hypo Variable pattern, small lesions hypervascular, significant restriction
Metastases Primary tumor, metastatic syndromeHyper Hypo Hypo Restriction Hypo Hyper ++ Iso/hypo Hypo Hypo Multiple lesions hypervascularity, halo signs signs of malignancy