Etiopathogenesis of internal and external genital endometriosis (evolution of views)

Abstract

The etiology and pathogenesis of endometriosis and adenomyosis, as well as their interrelations, are not fully understood and are the subject of discussions and research. The question remains whether the endometriosis and adenomyosis are different diseases, or they represent different phenotypes of the same pathology. Considerations are given about the etiopathogenesis of these diseases, which existed in different years. It is now recognized that endometrioid heterotopias in adenomyosis and endometriosis are derivatives of the basal layer of the endometrium - endometrial stem cell. There are three possible ways of spreading the stem cells of the basal layer of the endometrium, leading to the formation of foci of endometriosis and adenomyosis: retrograde cast into the abdominal cavity with menstrual blood, invasive growth in myometrium due to the mechanism of epithelial-mesenchymal transformation and disruption of the endometrium and myometrium connection zone, and neonatal bleeding. Thus, the mechanisms of the appearance of foci of endometriosis in various organs and tissues are quite diverse and are associated with the primary dysfunction of the endometrium itself, retrograde menstruation, pathological regeneration accompanied by epithelial-mesenchymal transformation, as well as pathological changes in the endometrium and myometrium connection zone, neonatal bleeding. The severity of the clinical course of endometriosis, the frequency of relapse after surgical treatment, the effectiveness of conservative therapy, and the overcoming of infertility are probably due to the mechanism of development of this pathology in each specific case.