Endometrial stromal sarcomas: a modern view of classification, diagnosis and molecular subtypes

Endometrial stromal sarcomas represent a rare but clinically and morphologically significant group of mesenchymal uterine neoplasms. The current Who classification (2020, 5^th edition) includes four main categories: endometrial stromal nodule, low-grade endometrial stromal sarcoma, high-grade endometrial stromal sarcoma and undifferentiated uterine sarcoma. This review summarizes the key stages in the evolution of endometrial stromal sarcomas classification, from early morphology-based approaches to modern molecular-genetic typing. it presents the characteristic morphological, immunohistochemical, and molecular features of low-grade endometrial stromal sarcoma, high-grade endometrial stromal sarcoma and undifferentiated uterine sarcoma and diagnostic criteria for their differential diagnosis. particular attention is given to the role of chromosomal translocations and gene fusions, including jaZf1-suZ12, YWHAE‑NUTM2A / B, BCOR‑ZC3H7B and BCOR‑ITD, in the pathogenesis and molecular subclassification of endometrial stromal sarcoma. in light of recent molecular findings, the authors emphasize the importance of a comprehensive diagnostic approach combining histological evaluation, immunohistochemical marker panels, and molecular testing. This integrated strategy enhances diagnostic accuracy and supports the development of personalized treatment plans. The evolution of endometrial stromal sarcoma classification reflects a global trend toward the shift from phenotypic to genotypic diagnosis in modern oncopathology.

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