Surface ultrastructure of human endometrium. Effect of hormonal status and neoplastic progression.

The structure, size and number of uterine endometrial surface epithelial cells and specialized structures, cilia and microvilli were analyzed by light microscopy, transmission and scanning electron microscopy. The purpose was to further our understanding of the biological, morphological and prognostical implications of change in hormonal status and neoplastic progression. The results of this study showed that the quantitative and qualitative alterations followed a similar pattern: the cilia and microvilli were minimally developed in atrophic endometrium, and gradually progressed in size and number in relation to oped in atrophic endometrium, and gradually progressed in size and number in relation to the hormonal cycle and hyperplastic endometrium, unless associated with cellular atypia. Lesions with atypical adenomatous hyperplasia showed irregular and disorganized surface structure, progressively more apparent in specimens from adenocarcinomas. Decreasing degree of differentiation of the tumor and radiation treatment caused a reduction in number and size, as well as derangement in the structure of cilia and microvilli. The results showed the sensitivity of the uterine lining to hormonal changes, the distinction between different types of edometrial hyperplasia and the close interrelationship between atypical adenomatous hyperplasia and early adenocarcinoma, as well as the extent and severity of different clinical entities, including radiation treatment.