The clinical diagnosis of atypical uterine bleeding requires differentiation of the histological diagnosis between hyperplastic processes with and without atypia and highly differentiated (grade 1) endometrial adenocarcinomas, taking into account the further treatment tactics of patients. The lack of a common picture during the study of the material after endometrial scraping necessitates the improvement of histological and immunohistochemical criteria for verification of the corresponding diagnoses.

Aim of the study. To investigate the characteristics of the expression of the 3-marker panel in hyperplastic processes of the endometrium and highly differentiated endometrioid adenocarcinomas; to determine the diagnostic sensitivity and specificity of the 3-marker panel in endometrial glandular hyperplasia with and without atypia and endometrioid adenocarcinomas (EA) grade 1 of the endometrium using the latest international classification data and taking into account the diagnostic search capabilities of the healthcare sector of Ukraine.

Materials and methods. A retrospective analysis of 60 cases of postoperative material and excision of women for the period from 2021 to 2023 with a histological diagnosis of atypical and atypical glandular hyperplasia of the endometrium and highly differentiated (grade 1) EA included an assessment of morphological, histological, immunohistochemical characteristics with subsequent statistical processing of the results obtained.

Results. In the studied sample (n = 60), a statistically significant relationship was established between the frequency of PTEN and PAX-2 expression with process atypia (atypical hyperplasia → atypical hyperplasia → G1 adenocarcinoma) according to the Cochran-Armitage test (PTEN: Z = -3.95; p < 0.001; PAX-2: Z = -4.64; p < 0.001), which was confirmed by the χ2-test (PTEN: p < 0.001; Cramer V = 0.54; PAX-2: p < 0.001; Cramer V = 0.60) and Spearman correlation (PTEN: ρ = -0.510; p < 0.001; PAX-2: ρ = -0.599; p < 0.001). For PAX-8, no intergroup differences were found (p > 0.38 for each of the three above-mentioned tests), the expression remained consistently high in all groups. Therefore, the loss of PTEN and PAX-2 expression was associated with a more malignant process in this cohort, while PAX-8 did not demonstrate discriminatory ability between the considered groups.

Conclusions. The feasibility of using the PTEN and PAX-2 panel in endometrial hyperplastic processes as a prognostic was argued.