Objective: To establish whether karyometry was likely to detect change in the proportion of abnormal cells in random periareolar fine needle aspiration (RPFNA) specimens from high-risk women in a 6-month prevention trial with an aromatase inhibitor.
Study design: Papanicolaou-stained ThinPrep slides of RPFNA samples from 11 of 42 women were digitally recorded at high resolution, with 200 cells measured per slide, at baseline (BL) and at the end of study (ES) after 6 months. The nuclear chromatin pattern characteristics were assessed by multivariate analytic techniques; determination of nuclear abnormalities was performed and cells that showed expression of abnormality were identified.
Results: The BL FNA samples contain approximately 90% cells with a chromatin pattern as expected in a normal cell population. A small subpopulation of cells had deviations from normal. At ES the proportion of these cells was reduced, to a statistically significant degree,from < 10% to 2-5%.
Conclusion: Nuclear karyometry is a promising technique for characterizing the proportion of cells deviating from normal in cytologic specimens and should be explored further as an intermediate endpoint in prevention trials.