STUDIES ON THE PROLIFERATIVE ACTIVITY OF DIETHYLNITROSAMINE-INDUCED HEPATOCELLULAR CARCINOMAS IN MONKEYS

In this study, synthetic phase fractions (SPFs) determined by flow cyt ometry and AgNOR counts were analysed in benign liver lesions (regener ative nodules and adenomas), hepatocellular carcinomas (HCCs), and lun g metastases of a monkey hepatocarcinogenesis model to find out if AgN OR counts and SPFs can discriminate between malignant and non-malignan t liver lesions, The average per cent SPF values and the AgNOR counts were significantly (P = 0.001) increased in regenerative liver nodules (5.30 per cent; 4.96), adenomas (5.34 per cent; 3.46) and well-differ entiated HCCs (6.75 per cent; 4.47), compared with the untreated contr ol livers (3.18 per cent; 0.98), but the differences between these thr ee groups were not significant, In the poorly differentiated HCC group , however, the average SPF value (9.60 per cent) and AgNOR count (7.14 ) were significantly higher than in any of the other liver lesions exa mined, A significant correlation was found between the SPF values and AgNOR counts on the one hand, and differentiation and cytological grad e of the HCC samples on the other. The results of this study show that the SPF values and AgNOR counts are not reliable in differentiating b etween regenerating liver nodules, adenomas, and experimental well-dif ferentiated HCCs. The SPF value, however, may serve as a prognostic fa ctor in HCC, since it was found to be significantly higher in HCCs wit h lung metastasis than in those without. (C) 1997 by John Wiley & Sons , Ltd.