Imaging methods in hepatocellular carcinoma

Abstract

Hepatocellular cancer (HCC) is the third most common cause of cancer-related death. Ultrasonography reveals 75–90% of HCC lesions in cirrhotic patients. Ambiguous and non-characteristic appearance of HCC lesions in this examination results in low efficacy of early detection. Multiphase computer tomography (CT) is a recommended method of assessment of HCC. Arterial and venous-portal phases allow to visualize most of HCC and equilibrium phase provides prognostic information. Dynamic contrast- enhanced magnetic resonance imaging (MR) after contrast medium administration is conducted similarly to computer tomography examination. Arterial phase allows to detect hipervascular lesions, as most of HCC, and venous-portal phase permits to assess lesions with poor arterial supply. The sensitivity of MR examination is slightly higher than CT’s and rises after hepatotropic contrast medium infusion. Enhancement in hepatocyte-specific phase is possible only within normal hepatocytes, thus no enhancement expose pathological liver cells. Moreover, 20% of HCC lesions smaller than 2 cm has non typical arterial phase enhancement and their identification is possible only in hepatocyte-specific phase. Barcelona Clinic Liver Cancer Group guidelines allow to diagnose HCC in cirrhotic patients, without the need for biopsy, on basis of typical radiological features in dynamic CT-scan or MR study: intensive enhancement in arterial phase and persistent ‘washout’ of contrast medium from HCC lesion in venous-portal and equilibrium phases.
Onkol. Prak. Klin. 2011; 7, 2: 73–83