Endometrial stromal sarcoma – the new genetic paradigm

Abstract

Endometrial stromal sarcoma (ESS) is a gynaecological sarcoma that is composed of cells that resemble those of proliferative-phase endometrial stroma. The 2014 World Health Organization tumour classification system separates ESS into low-grade and high-grade types, which are histologically, genetically and clinically distinct from undifferentiated uterine sarcoma (UUS). Low-grade ESSs frequently contain chromosomal rearrangements that result in JAZF1-SUZ12 fusion or equivalent genetic fusions. Although most low-grade ESSs show classic histological features that closely resemble those of proliferative-phase endometrial stroma, there are several histological variants that are associated with the same genetic fusions as seen in the classic type. High-grade ESS is defined by the presence of YWHAE-NUTM2A/B (YWHAE-FAM22A/B) fusions. High-grade ESSs are clinically more aggressive than low-grade ESSs, but are associated with a lower mortality rate than UUSs. The histological and immunophenotypic features of these different types of ESS, and their diagnostic considerations, are the subjects of this review.

Endometrial Stromal Sarcoma of the Uterus: Magnetic Resonance Imaging Findings Including Apparent Diffusion Coefficient Value and Its Correlation With Ki-67 Expression

“…19,20 Pathological studies showed a more commonly degenerative change in HGESS than in LGESS. 1,3,4 In our series, degenerative changes were observed in 7 of 13 LGESSs, whereas those changes were observed in both of the 2 HGESSs. Sometimes, the findings of LGESS may mimic a uterine leiomyoma with cystic degeneration 19 ; however, our study showed that the cystic degeneration radially distributed from the central part of the mass to the periphery in 3 LGESSs, which were also a characteristic feature.…”

“…Clinically, patients with LGESS are more likely to be younger women and to be diagnosed at an early stage with a relatively favorable prognosis. 3,4 Radical total hysterectomy and bilateral salpingooophorectomy are the standard surgical therapy for early stage ESS. 5 With the development of personalized medicine, conservative fertility-sparing management in young patients has attracted extensive attention.…”

Practical issues related to uterine pathology: endometrial stromal tumors

“…Endometrial stromal tumors can be divided into four main categories, which are currently recognized by the WHO (2014) [1][2][3] (A) endometrial stromal nodule (ESN), (B) endometrial stromal sarcoma, low-grade, (C) endometrial stromal sarcoma, high-grade, and (D) UUS. The purpose of this review is to highlight the salient clinical, morphologic, immunohistochemical, and genetic differences that allow their distinction.…”

Low-grade endometrial stromal sarcoma with extensive sex cord differentiation, heterologous elements, and complex atypical hyperplasia: Case report and review of literature

“…A rearranged PHF1 gene is identified in the majority of the remaining cases (Lee and Nucci, 2014). A subset of LG-ESS's without demonstrable genetic rearrangements have been reported, and these are thought to represent variant translocations.…”