[Preneoplasia of the liver. Definition--differential diagnosis--clinical consequences]

The great advances in radiological imaging techniques and their widespread availability have focused attention on hepatic premalignant nodular lesions. The histological differential diagnosis of these nodules can often be difficult, especially in needle biopsy specimens with limited material. Diagnostic considerations differ significantly between livers with and without cirrhosis: In the noncirrhotic liver, the differential diagnosis includes liver cell adenoma, nodular regenerative hyperplasia, and hepatocellular carcinoma. In cirrhosis, dysplastic nodules (low and high grade), dysplasia (large and small cell) as well as hepatocellular carcinoma may occur. The standardization and the uniform use of the nomenclature of these entities are necessary for a better understanding of the biological nature and etiopathology of these lesions. Only a commonly accepted nomenclature makes a comparison of different therapeutic treatment regimens feasible.