Benign endometrial hyperplasia and endometrioid intraepithelial neoplasia: aspects of classification, etiology, treatment

Relevance. In this work, we have covered the aspects of classification, etiology, and treatment of two cellular and structural variants of endometrial hyperplasia: benign endometrial hyperplasia and endometrioid intraepithelial neoplasia, which is an equivalent term for atypical endometrial hyperplasia. Two classification systems have been reviewed: the WHO 2014 classification and the Yokohama classification. The etiological basis is primarily hyperestrogenemia with a suppressed progesterone status. Risk groups have been described. The article provides information about  the dependence on monoclonal aberrations and the uterine microbiome. It also discusses treatment options for abnormal uterine bleeding, which is a recognized component of the clinical Triad A. The article describes methods of fertility-preserving treatment using surgery and self-administered hormone therapy through the use of LNG-IUDs. The role of a-GnRH in the treatment of this endometrial pathology is mentioned. ART can not only fulfill the reproductive intentions of patients but also increase the period of remission through pregnancy. Treatment tactics should be supported by the results of MSI testing, as immuno-associated therapy is more effective when this immunohistochemical marker is detected.

Objective: to highlight in this work the aspects of classification, etiology, treatment of endometrial hyperplasia typical (benign endometrial hyperplasia) and atypical morphoarchitectonics (endometrioid intraepithelial neoplasia).

Materials and methods. Data collection in scientometric PubMed, E-library, CyberLeninka, as well as in bibliographic sources. Time frame: 2000–2025.

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