Proliferative activity in normal endometrium and endometrial carcinoma measured by immunohistochemistry using Ki-67 and anti-DNA polymerase alpha antibody, and by flow cytometry.

The proliferative activity of various parts of normal and malignant endometrium was evaluated using an immunohistochemical approach and flow cytometry (FCM). The two monoclonal antibodies, Ki-67 and anti-DNA polymerase alpha antibody (anti-poly alpha antibody) were used to detect the proliferative activity of cells, and the percentage of the Ki-67 and anti-poly alpha positive cells were measured. Proliferative indices (PI; percentage of S and G2M phase) and DNA ploidy were measured by FCM. Normal endometrial specimens from 29 patients with benign diseases were used and three different parts (fundus, middle, and low part of the uterus) were examined. In the proliferative phase of normal endometrium, there was no significant difference in the proliferative activity in the three parts. In 20 patients with endometrial carcinomas with myometrial invasion, tissues were taken from the myometrial invasive site and the central part of the tumor tissue. In the cases of endometrial carcinoma, the myometrial invasive site had a higher proliferative activity than central part of the tissue. The proliferative activity measured by the immunohistochemistry was correlated with the histological grade of malignancy, but it was not consistent with PI by FCM. This suggests that the proliferative activity measured by the immunohistochemistry is independent of flow cytometric PI.