Advanced precancerous lesions in the liver.

We will focus on precursors of the most common liver cancer, i.e. hepatocellular carcinoma (HCC), which takes place in 90% of cases in a hepatitis/cirrhotic setting. High grade dysplastic nodules (HG-DN) are small sizable nodules and the most advanced precancerous lesions of the liver, with a risk of malignant transformation of about 30-40% at 24 months. We will survey the diagnostic distinction between them and early HCC from a clinical, radiological and pathological point of view. The use of a diagnostic algorithm supported by international guidelines is the best practice to manage HG-DN and early HCC. There is no typical imaging for HG-DN, needing all of them to be biopsied for characterization. The natural history of HG-DN is not predictable in individual cases and additional markers should be validated to increase the diagnostic accuracy and predict the behaviour. The treatment of HG-DN is under investigation.