A place of siderophage in cellular microenvironment of endometrioid ovarian cyst in the course of its evolution

Abstract

Background. The term «endometriosis» implies the existence of viable tissue of ectopic endometrium in different anatomic locations outside the uterine cavity. The etiopathogenesis of this disease still remains a matter of debate, and one of the main issues of morphology of endometriosis is the interrelation of the vascular bed and of its cellular environment, especially macrophages and siderophages. Aim. Was to identify the dynamics of variation of correlation relationships between siderophages and other cell populations within the wall of the endometrioid cyst and the number of vessels. Materials and Methods. Endometrioid ovarian cysts obtained from 57 patients after surgical treatment, were subjected to histologic examination. Preliminarily all the studied endometrioid cysts were categorized to «young», «mature» and «old» on the basis of certain morphological signs. After staining with hematoxylin and eosin, cellular environment and also the number of vessels were counted in 10 fields under x400 magnification. The data obtained were further subjected to statistical analysis. Results. At the stage of a «young» endometrioid cyst siderophages are rare and are represented by single cells that form the following correlations: negative with neutrophils in the uterine epithelium and stroma of the endometrioid lining, and positive – with neutrophils of the underlying fibrous layer. In addition, there is a single positive correlation between siderophages and macrophages in the stroma of the endometrioid lining. A negative correlation was found between the number of vessels and siderophages in the stroma of the endometrioid lining. A marked increase in the number of siderophages is a distinctive sign of «mature» endometrioid cysts, which may be an evidence of emerging disorders of the blood supply to the tissues of the heterotopia. Significant changes occur in the correlations between siderophages and other cell populations that considerably increase in number. A negative correlation is preserved between the number of vessels and siderophages. In comparison with “young” and “mature” endometrioid cysts, siderophages and cell populations of “old” endometrioid cysts lose almost all their correlations. The correlations formed between the number of vessels and the cell populations do not differ much from those in the “mature” endometrioid cyst. Conclusion. Absence of siderophages in the stroma of endometrioid lining is an indicator of its sufficient vascularization. The macrophage cell center has to maintain homeostasis through polarization of endometrium-associated macrophages to macrophages possessing the function of phagocytosis with subsequent elimination of the products of blood supply disorders and with formation of siderophages.