title: Radiological diagnosis of hepatocellular carcinoma.
abstract: Diagnosis of hepatocellular carcinoma (HCC) still remains a challenging issue. In the setting of liver cirrhosis, international guidelines have set the noninvasive criteria for HCC diagnosis, represented by the detection of contrast hyperenhancement in the arterial phase (wash-in) and hypoenhancement in the portal or delayed phase (wash-out) with dynamic multi-detector computer tomography or magnetic resonance (MR) imaging. Although highly specific, this typical enhancement pattern has relatively low sensitivity, since approximately one-third of HCC nodules are characterized by atypical enhancement patterns. In atypical HCC nodules larger than 1 cm, the majority of international guidelines recommend liver biopsy. However, there is an increasing interest in exploiting new noninvasive diagnostic tools, to increase the sensitivity of radiological diagnosis of HCC. Diffusion-weighted MR imaging and MR hepatobiliary contrast agents may represent useful tools for the detection and characterization of borderline hypovascular lesions by providing functional information such as water molecule motion in diffusion-weighted imaging and residual hepatobiliary function, which can be impaired early during the course of hepatocarcinogenesis. Also, dual-energy computed tomography (CT) represents an interesting new CT technology that could increase detectability and conspicuity of hypervascular lesions, thus possibly improving CT sensitivity in small HCCs. However, more data and further developments are needed to verify the usefulness of these new technologies in the diagnosis of HCC and to translate these recent advances into clinical practice.
authors: Department of Diagnostic and Interventional Radiology, Pisa University Hospital, Pisa, Italy.
authors: Irene
authors: I
authors: Bargellini
authors: Department of Diagnostic and Interventional Radiology, Pisa University Hospital, Pisa, Italy.
authors: Valentina
authors: V
authors: Battaglia
authors: Department of Diagnostic and Interventional Radiology, Pisa University Hospital, Pisa, Italy.
authors: Elena
authors: E
authors: Bozzi
authors: Department of Diagnostic and Interventional Radiology, Pisa University Hospital, Pisa, Italy.
authors: Dario Luca
authors: DL
authors: Lauretti
authors: Department of Diagnostic and Interventional Radiology, Pisa University Hospital, Pisa, Italy.
authors: Giulia
authors: G
authors: Lorenzoni
authors: Department of Diagnostic and Interventional Radiology, Pisa University Hospital, Pisa, Italy.
authors: Carlo
authors: C
authors: Bartolozzi
keywords: computed tomography; contrast agents; hepatocellular carcinoma; liver cirrhosis; magnetic resonance imaging; ultrasound