Evolution of DNA content in small and well-differentiated hepatocarcinoma.

DNA ploidy of 10 well-differentiated hepatocarcinomas was evaluated by densitometry on smears obtained by fine needle aspiration biopsy (FNAB) with ultrasound guidance. Because of diagnostic difficulties or an increase in tumor size, FNAB was repeated once in six cases and twice in four. All the material collected was then analyzed to study the variation of DNA content over time in these neoplasms. The study was performed on Feulgen-stained slides using an IBAS image analyzer system. DNA ploidy was evaluated by visual interpretation of the corresponding histograms and by calculating the 5c exceeding rate (5cER), 2c deviation index (2cDI) and DNA malignancy grade (DNA-MG). In the first samples seven cases were euploid (four diploid and three polyploid), with 5cER < 5; three cases were aneuploid, with 5cER > 5. In the second samples, taken after four or six weeks, eight cases became aneuploid, with 5cER > 5, and two cases were polyploid, with 5cER > 5. Four cases in which a third FNAB was performed resulted in aneuploidy, with 5cER > 5. A progressive increase in aneuploidy, 5cER and DNA-MG values was observed in six cases in the second FNAB and in one case in the third FNAB along with the increasing size of the nodules. In only one case we observed a paradoxical reduction in the 5cER in the third FNAB; the corresponding histogram remained aneuploid. Limitations could have occurred because of sampling small nodules under ultrasound guidance and because of the relatively small number of cells measured. DNA evaluation seems to be useful in the diagnosis of hepatocarcinoma and in the study of its biologic features.