Surveillance and early diagnosis of hepatocellular carcinoma.

Patients at high risk for developing hepatocellular carcinoma (HCC) should be enrolled in surveillance programs based on ultrasound (US) examinations performed at 6-month intervals. Nodules found during US surveillance that are smaller than 1 cm should be followed-up with US at 3-month intervals. If the nodule found during US surveillance is larger than 1 cm, it should be investigated further with contrast-enhanced dynamic radiological studies, including US, multidetector computed tomography, or magnetic resonance imaging. If the appearance is typical for HCC (i.e., the lesion shows hypervascularization in the arterial phase with washout in the portal venous or the equilibrium phase), biopsy is considered unnecessary and the lesion can be treated as HCC. For nodules between 1 and 2 cm, it is currently recommended that such non-invasive diagnosis be based on the evidence of coincidental features typical for HCC from at least two dynamic imaging techniques. If the vascular profile on imaging is not characteristic or the nodule is detected in a non-cirrhotic liver, biopsy should be performed. If the biopsy is negative for HCC, patients should be followed-up by imaging studies performed at 3-month intervals until the nodule either disappears, enlarges, or displays diagnostic characteristics of HCC.