Karyometry in endometrial adenocarcinoma of different grades.

Objective: To characterize nuclei from adenocarcinoma of the endometrium of different grades in order to establish whether significantly different nuclear subpopulations exist.

Study Design: A total of 1,400 nuclei from 14 cases of adenocarcinoma of the endometrium of grades 1, 2 and 3 were recorded, and 600 nucleifrom normal, secretory phase glandular endometrial epithelium were used as a reference data set. Karyometric features were computed and a discriminant function derived to define a trend in feature values for nuclei from lesions of different grades. The nuclei from lesions of different grades were processed by a nonsupervised learning algorithm in an effort to detect and define subpopulations.

Results: Nuclei from grade 1 lesions represented a near-diploid stemline, whereas nuclei from grade 3 lesions formed an aneuploid set with a mode around 3N. The existence of three subpopulations with statistically different nuclear chromatin patterns could be shown for nuclei from each grade. In each grade these three subpopulations occupied the same relative position in feature space. For grade 1 lesions all three subpopulations were near diploid, for grade 3 lesions all three were approximately triploid.

Conclusion: The nuclei in adenocarcinoma of the endometrium form a heterogeneous set, with subpopulations of distinctly different chromatin patterns and different ploidy. This should be taken into consideration in assessing the efficacy of chemopreventive intervention.