The purpose of this study was to investigate the influence of different cell extraction procedures on relative nuclear
DNA content (IOD), nuclear area, and texture features of Feulgen-stained nuclei. In imprints and smears of fine-needle aspirates and
suspensions from one human liver specimen, 50 diploid, 50
tetraploid, and 25 octaploid nuclei were measured from each slide. In addition, for
DNA measurements, the progressive mean of IOD and
tetraploid/diploid and octaploid/diploid ratios was calculated. The results show that the progressive mean of the IOD is constant after measuring 25-30 nuclei. For the three types of specimens, the IOD of diploid nuclei varied slightly. The average coefficient of variation was about 5% for the fine-needle aspirates, imprints, and
suspensions. For all tissue sampling methods, the 99% confidence limits of the
tetraploid/diploid ratio and octaploid/diploid ratio were within the range of 1.9-2.1 and 3.7-4.3, respectively. The nuclear area and most of the texture features showed a significant difference (p less than 0.01) between the three sampling methods in all nuclear populations. In conclusion, different tissue sampling methods have little or no effect on
DNA-related IOD measurements, whereas the outcome of nuclear area and texture features is very dependent of the cell extraction procedure.