THE NUCLEOLAR ORGANIZER REGIONS IN HYPERPLASTIC AND TUMOROUS LESIONS OF THE HUMAN LIVER

The alterations of the argyrophil nucleolar organizer regions (AgNORs) have been studied in hyperplastic and neoplastic human liver lesions. The material studied included: 11 focal nodular hyperplasias (FNH), 3 adenomas, 19 hepatocellular carcinomas (HCC), 2 hepatoblastomas, 8 li ver metastases. In 5 cases tumor-free (normal) liver was also availabl e for study. The mean AgNOR numbers were significantly increased in al l of these lesions (in FNHs 3.36 +/- 1.43, in the adenomas 2.48 +/- 1. 29, in the HCCs 3.32 +/- 1.43, in the hepatoblastomas 3.33 +/- 1.33 an d in the metastases 4.86 +/- 1.54) compared to those observed in norma l liver (0.86 +/- 0.85). The highly increased AgNOR number in FNHs was particularly surprising and it seemed to us that based on AgNOR numbe rs the FNHs could be divided into two groups. With the exception of he patoblastomas in all primary liver lesions the AgNOR counts distribute d on a rather broad scale resulting in overlapping in hyperplastic and tumorous cases. The authors concluded that the AgNOR counts reflect o nly the proliferative activity of a given cell population and at least in the liver they cannot serve as basis for distinction between the h yperplastic, benign and malignant neoplastic lesions.