Nucleolar organiser regions in normal, cirrhotic, and carcinomatous livers.

A series of 54 liver biopsy specimens was studied by means of the argyrophil (AgNOR) technique for nucleolar organiser region (NOR)-associated proteins. These included normal livers and livers affected by chronic active hepatitis, cirrhosis, hepatocellular carcinoma and adenoma. Four of the cases of cirrhosis showed liver cell dysplasia. The mean numbers of NOR sites in normal, cirrhotic, and carcinomatous livers were significantly different: adenoma had similar mean counts to those in chronic active hepatitis (CAH). There was no overlap between the ranges of NOR counts in normal, cirrhotic, and malignant liver specimens. Where cirrhosis and hepatocellular carcinoma were present in the same specimen, the AgNOR counts were higher in the carcinomatous than cirrhotic areas. To investigate the prospective value of the method a further seven biopsy specimens were studied; in these it had not been possible to decide on a diagnosis between normality and cirrhosis or cirrhosis and hepatocellular carcinoma. In all seven specimens a repeat biopsy or necropsy gave results as predicted by AgNOR staining. It is therefore proposed that quantitation of staining for NOR-associated proteins is a diagnostically useful method in liver disease.