High-grade Endometrial Stromal Sarcoma Research Articles

Uterine Endometrial Stromal Tumors With Pure Low-Grade Morphology Harboring YWHAE::NUTM2 Fusions: Report of a Case Series Emphasizing Potential for High-Grade Transformation and Aggressive Behavior.

Uterine endometrial stromal sarcomas (ESS) with YWHAE::NUTM2 gene fusions are typically morphologically high-grade tumors composed of atypical round cells, sometimes associated with a low-grade fibromyxoid component; they are currently included in the category of high-grade ESS (HGESS). We report 5 morphologically pure low-grade endometrial stromal tumors harboring YWHAE::NUTM2 fusions, including 1 endometrial stromal nodule (ESN) and 4 low-grade endometrial stromal sarcomas (LGESS), an association only occasionally reported previously. Patients ranged from 30 to 51 (mean=43) years and tumors from 4.5 to 7.5cm (mean=5.7). All were stage I at diagnosis (confined to the uterus). Microscopically, the 4 LGESS showed extensive "tongue-like" invasion of the myometrium, and the ESN was entirely confined to the endometrium with no myometrial invasion. All tumors were composed entirely of morphologically uniform bland ovoid cells resembling proliferative endometrial stroma. A fibromyxoid component was seen in 1 LGESS and the ESN; in the LGESS, this was the sole component. Atypical round cells characteristic of YWHAE::NUTM2 HGESS were not identified. Mitotic count ranged from <1 to 13 per 10 high-power fields (mean: 3). CD10 was positive in 2/4 (focal), estrogen receptor in 5/5 (focal=1; diffuse=4), progesterone receptor in 5/5 (focal=1; diffuse=4) and cyclin D1 was diffusely positive in 3/4. Follow-up was available in all 5 patients and ranged from 6 to 159 months (mean=72). Two patients with LGESS had recurrent disease at 15 and 155 months; 1 showed predominantly LGESS with rare round cells in the initial recurrence and pure HGESS in a subsequent recurrence, while the other patient's recurrent tumor was predominantly HGESS (90%) in a background of focal fibromyxoid LGESS (10%). Both patients rapidly progressed and died of disease within 5 months of high-grade recurrence. We show that rare cases of morphologically pure low-grade endometrial stromal tumors, some but not all with a fibromyxoid component, harbor YWHAE::NUTM2 fusions and may recur rapidly, with transformation to HGESS and aggressive behavior. Our findings suggest that at least a subset of YWHAE::NUTM2 HGESS evolves from LGESS. We suggest that cyclin D1 and CD10 staining should be performed in all LGESS. Diffuse staining for cyclin D1 and/or negative or focal staining for CD10 should suggest the possibility of a YWHAE::NUTM2 fusion, and appropriate molecular testing should be undertaken. Since no single morphological or immunohistochemical parameter is entirely sensitive for fusion status, we also suggest that testing for a YWHAE::NUTM2 gene fusion should be considered in all cases of LGESS and, if a fusion is present, this should raise the possibility of subsequent high-grade transformation and aggressive behavior, even though such cases should still be categorized as LGESS. Although seemingly rare, ESN and LGESS with YWHAE::NUTM2 fusions may be under-recognized due to a lack of routine fusion testing.

Breast metastasis in high-grade endometrial stromal sarcoma (HG-ESS) with BCOR rearrangement: a case report of a novel metastatic site

BackgroundThe ZC3H7B-BCOR fusion gene has recently been described in tumours with kinship to so-called high grade endometrial stromal sarcoma (HG-ESS). This subset of tumour behaves similarly to YWHAE-NUTM2A/B HG-ESS, however, they are both morphologically and immunophenotypically distinct neoplasms. The identified rearrangements in the BCOR gene have been accepted as both the driver and requisite feature in creating a novel sub-entity within the category of HG-ESS.Preliminary investigations into BCOR HG-ESS have shown similar outcomes to YWHAE-NUTM2A/B HG-ESS, with patients typically presenting with high stage disease. Clinical recurrences and metastases to lymph nodes, sacrum/bone, pelvis/peritoneum, lung, bowel and skin have been identified. In this report, we describe a case of BCOR HG-ESS, that is deeply myoinvasive and widely metastatic. Metastatic deposits include a mass in the breast discovered on self-examination; a metastatic site that has yet to be reported in the literature.Case presentationA 59-year-old female underwent biopsy for post-menopausal bleeding, yielding a diagnosis of “low-grade spindle cell neoplasm with myxoid stroma and endometrial glands”, favouring endometrial stromal sarcoma (ESS). She was then referred for total hysterectomy and bilateral salpingo-oophorectomy. The resected uterine neoplasm was both intracavitary and deeply myoinvasive with morphology consistent with that of the biopsy specimen. Characteristic immunohistochemistry (IHC) was noted, and fluorescence in situ hybridization confirmed BCOR rearrangement, supporting a diagnosis of BCOR HG-ESS. A few months postoperatively, the patient underwent needle core biopsy of the breast which revealed metastatic HG-ESS.ConclusionsThis case highlights some of the diagnostic challenges posed by uterine mesenchymal neoplasms, and exemplifies the emerging histomorphologic, immunohistochemical, molecular and clinicopathologic features of the recently described HG-ESS with ZC3H7B-BCOR fusion. It adds to the body of evidence supporting the inclusion of BCOR HG-ESS as a sub-entity of HG-ESS within the endometrial stromal and related tumours subcategory of uterine mesenchymal tumors, as well as the poor prognosis and high metastatic potential of this tumor.

Genomic and Transcriptomic Characterization Revealed the High Sensitivity of Targeted Therapy and Immunotherapy in a Subset of Endometrial Stromal Sarcoma.

The unique chromosomal rearrangements of endometrial stromal sarcoma (ESS) make it possible to distinguish high-grade ESS (HGESS) and low-grade ESS (LGESS) from the molecular perspective. Analysis of ESS at the genomic and transcriptomic levels can help us achieve accurate diagnosis of ESS and provide potential therapy options for ESS patients. A total of 36 ESS patients who conducted DNA- and/or RNA-based next-generation sequencing were retrospectively enrolled in this study. The molecular characteristics of ESS at genomic and transcriptomic levels, including mutational spectrum, fusion profiles, gene expression and pathway enrichment analysis and features about immune microenvironment were comprehensively explored. TP53 and DNMT3A mutations were the most frequent mutations. The classical fusions frequently found in HGESS (ZC3H7B-BCOR and NUTM2B-YWHAE) and LGESS (JAZF1-SUZ12) were detected in our cohort. CCND1 was significantly up-regulated in HGESS, while the expression of GPER1 and PGR encoding estrogen receptor (ER) and progesterone receptor (PR) did not differ significantly between HGESS and LGESS. Actionable mutations enriched in homologous recombination repair, cell cycle, and phosphoinositide 3-kinase/AKT/mammalian target of rapamycin pathways were detected in 60% of HGESS patients. Genes with up-regulated expression in HGESS were significantly enriched in five immune-related pathways. Most HGESS patients (85.7%) had positive predictors of immunotherapy efficacy. Moreover, immune microenvironment analysis showed that HGESS had relatively high immune infiltration. The degree of immune infiltration in HGESS patients with ZC3H7B-BCOR fusion was relatively higher than that of those with NUTM2B-YWHAE fusion. This study investigated the molecular characteristics of ESS patients at the genomic and transcriptomic levels and revealed the potentially high sensitivity of targeted therapy and immunotherapy in a subset of HGESS with specific molecular features, providing a basis for guiding decision-making of treatment and the design of future clinical trials on precision therapy.

An Unusual Endometrial Stromal Neoplasm With JAZF1-BCORL1 Rearrangement.

Endometrial stromal tumors represent the second most common category of uterine mesenchymal tumors. Several different histologic variants and underlying genetic alterations have been recognized, one such being a group associated with BCORL1 rearrangements. They are usually high-grade endometrial stromal sarcomas, often associated with prominent myxoid background and aggressive behavior. Here, we report an unusual endometrial stromal neoplasm with JAZF1-BCORL1 rearrangement and briefly review the literature. The neoplasm formed a well-circumscribed uterine mass in a 50-yr-old woman and had an unusual morphologic appearance that did not warrant a high-grade categorization. It was characterized by a predominant population of epithelioid cells with clear to focally eosinophilic cytoplasm growing in interanastomosing cords and trabeculae set in a hyalinized stroma as well as nested and fascicular growths imparting focal resemblance to a uterine tumor resembling ovarian sex-cord tumor, PEComa, and a smooth muscle neoplasm. A minor storiform growth of spindle cells reminiscent of the fibroblastic variant of low-grade endometrial stromal sarcoma was also noted but conventional areas of low-grade endometrial stromal neoplasm were not identified. This case expands the spectrum of morphologic features seen in endometrial stromal tumors, especially when associated with a BCORL1 fusion and highlights the utility of immunohistochemical and molecular techniques in the diagnosis of these tumors, not all of which are high grade.

High-Grade Endometrial Stromal Sarcomas With YWHAE::NUTM2 Gene Fusion Exhibit Recurrent CDKN2A Alterations and Absence of p16 Staining is a Poor Prognostic Marker

High-grade endometrial stromal sarcomas (HGESSs) are aggressive uterine tumors harboring oncogenic fusion proteins. We performed a molecular study of 36 HGESSs with YWHAE::NUTM2 gene fusion, assessing co-occurring genetic events, and showed that these tumors frequently harbor recurrent events involving the CDKN2A locus on chromosome 9p. Using array-based copy number profiling and CDKN2A fluorescence in situ hybridization, we identified homozygous and hemizygous deletions of CDKN2A in 18% and 14% of tumors (n = 22 analyzed), respectively. While all YWHAE-rearranged HGESSs with retained disomy for CDKN2A were immunohistochemically positive for p16INK4 (p16), all tumors with homozygous deletion of CDKN2A showed complete absence of p16 staining. Of the 2 tumors with a hemizygous deletion of CDKN2A, 1 showed diffuse and strong p16 positivity, whereas the other showed complete absence of staining. In the p16-negative case, we did not find intragenic mutations or DNA promoter methylation to explain the p16 protein loss, implicating other mechanisms in the regulation of protein expression. In our cohort, subclonal or complete absence of p16 staining was associated with worse overall survival compared with positive p16 staining (1-year overall survival: 28.6% vs 90.7%, respectively; n = 32; P < .001), with all 7 patients in the p16-negative group having succumbed to their disease within 2 years of diagnosis. Our results suggested CDKN2A alterations as a cooperative driver of tumorigenesis in a subset of HGESSs with the YWHAE::NUTM2 gene fusion and showed p16 to be a potential prognostic marker.

Endometrial Stromal Tumour: Clinicopathological Series of Seven Cases

Endometrial Stromal Tumour (EST) mimics other neoplasms and is difficult to diagnose due to its wide range of morphologies. This is a clinicopathological study of seven cases of EST, which includes Endometrial Stromal Nodule (ESN), Low-grade Endometrial Stromal Sarcoma (LGESS), and High-grade Endometrial Stromal Sarcoma (HGESS). The age ranges from 34 to 75 years. Five out of seven cases presented with abnormal uterine bleeding, abdominal pain, and were radiologically suspected to be leiomyomas. After histopathological and Immunohistochemical (IHC) examination, one was diagnosed as ESN, three as LGESS, and the remaining three cases as HGESS. One case was initially diagnosed as a cellular leiomyoma and experienced multiple recurrences, eventually being diagnosed as HGESS with a fatal outcome within 36 months of the onset of the first symptoms. ESN and LGESS should be differentiated from leiomyoma and leiomyosarcoma. IHC plays an important role in distinguishing these tumours from the more common smooth muscle counterparts.

Endometrial Stromal Sarcoma in a Young, Nulliparous Woman: A Case Report

Endometrial stromal tumours are tumours of endometrial stromal origin and are classified into Endometrial Stromal Nodule (ESN), Low-Grade Endometrial Stromal Sarcoma (LG-ESS), and High-Grade Endometrial Stromal Sarcoma (HG-ESS). LG-ESS and HGESS are rare tumours, accounting for 1% of uterine malignancies and 10% of uterine sarcomas. These tumours commonly occur in perimenopausal women between the ages of 45 and 50 years. Their incidence is rare in younger women. Endometrial stromal tumours are usually confused with leiomyoma, uterine Leiomyosarcoma (LMS), or other sarcomas. The authors here present a case report of a 28-year-old nulligravid patient who presented with a history of heavy menstrual bleeding and dysmenorrhea for a duration of six months. Ultrasonography of the abdomen and pelvis suggested fibroid with degenerative changes, and Magnetic Resonance Imaging (MRI) indicated leiomyoma variants such as: i) Stromal Tumours of Uncertain Malignant Potential (STUMP)/ atypical/cellular leiomyoma; ii) myxoid degeneration of leiomyoma. To arrive at a definitive diagnosis, myomectomy was performed considering the woman’s young age and nulliparity. Histopathology allowed for a differential diagnosis of LG-ESS, LMS, and cellular leiomyoma. Consequently, the patient underwent total abdominal hysterectomy with left salphingo opherectomy, right salpingectomy, and preservation of the right ovary. The definitive diagnosis is made by histopathological examination coupled with immunohistochemistry of the hysterectomy specimen. Hysterectomy is the definitive treatment of LG-ESS considering their ability to infiltrate and become malignant.

Treatment patterns for leiomyosarcomas, endometrial stromal sarcomas and adenosarcomas: a national cancer database study

Uterine sarcomas are a rare, heterogenous, group of cancers with limited data on optimal adjuvant treatment. We examined patterns of care for leiomyosarcomas (LMS), endometrial stromal sarcomas (ESS), adenosarcomas (AS), and mixed uterine sarcomas and assessed the utilization of adjuvant therapy for each histology. The National Cancer Database (NCDB) was queried for patients with non-metastatic uterine sarcoma diagnosed between 2004 and 2018 treated with surgery. Uterine carcinosarcomas were excluded. Adjuvant patterns of care and temporal treatment trends are evaluated, stratified by histology. Multivariable logistic regression model was constructed to identify predictors of receipt of radiation adjuvant therapy. Among 12,806 patients, 88% received a total hysterectomy and bilateral salpingo-oophorectomy (TH+BSO) and 42% received lymph node sampling (LNS). Surgery alone was the most common treatment modality for all histology groups (59.0%). Surgery with chemotherapy was the second most common form of treatment for LMS (33.1%) and mixed type tumors (29.6%). Surgery with radiation was the second most common treatment for high-grade ESS (10.8%) and AS (11.8%). External beam radiation therapy (EBRT) was the most common type of adjuvant radiation therapy utilized. Adjuvant radiation therapy (RT) has declined in LMS, from 27% in 2004 to 3% in 2018. Adjuvant chemotherapy for all histology groups has increased in use from 10% in 2004 to 28% in 2018. For uterine sarcomas, TH+BSO without LNS was the main surgical modality. Adjuvant therapy for uterine sarcomas is not commonly used, however high risk features including stage II/III, high grade, and more extensive lymph node sampling appear to increase the likelihood of adjuvant RT. The utilization of adjuvant chemotherapy in uterine sarcomas has increased over time, while RT has been decreasing.

Sarcoma of the Uterus. Guideline of the DGGG, OEGGG and SGGG (S2k-Level, AWMF Registry No. 015/074, April 2021).

Purpose This is an official guideline, published and coordinated by the Germany Society for Gynecology and Obstetrics (Deutsche Gesellschaft für Gynäkologie und Geburtshilfe, DGGG). Because of their rarity and heterogeneous histopathology, uterine sarcomas are challenging in terms of their clinical management and therefore require a multidisciplinary approach. To our knowledge, there are currently no binding evidence-based recommendations for the appropriate management of this heterogeneous group of tumors. Methods This S2k guideline was first published in 2015. The update published here is once again the result of the consensus of a representative interdisciplinary committee of experts who were commissioned by the Guidelines Committee of the DGGG to carry out a systematic search of the literature on uterine sarcomas. Members of the participating professional societies achieved a formal consensus after a structured consensus process. Recommendations 1.1 Epidemiology, classification, staging of uterine sarcomas. 1.2 Symptoms, general diagnostic workup, general pathology or genetic predisposition to uterine sarcomas. 2. Management of leiomyosarcomas. 3. Management of low-grade endometrial stromal sarcomas. 4. Management of high-grade endometrial stromal sarcoma and undifferentiated uterine sarcomas. 5. Management of adenosarcomas. 6.Rhabdomyosarcomas of the uterus in children and adolescents. 7. Follow-up of uterine sarcomas. 8. Management of morcellated uterine sarcomas. 9. Information provided to patients.

Uterine Leiomyosarcoma with a Novel RAB2A-PLAG1 Gene Fusion

Abstract Introduction/Objective Uterine leiomyosarcoma is a malignant neoplasm with three distinct histologic subtypes: spindle, epithelioid, and myxoid. Distinguishing leiomyosarcoma from mesenchymal uterine neoplasms such as endometrial stromal sarcoma can be challenging as they may exhibit a similar histology and immunohistochemical profile. In such cases, molecular studies can help achieve the definitive diagnosis. It has been shown that ~25% of the uterine myxoid leiomyosarcomas harbor TRPS1-PLAG1 and RAD51B-PLAG1 gene fusions. To our knowledge, no uterine leiomyosarcoma with RAB2A-PLAG1 gene fusion has been previously reported in the English literature. Methods/Case Report An 80-year-old woman presented with abnormal uterine bleeding. A large necrotic uterine mass with no evident lymphadenopathy was detected on imaging. Endometrial curettage demonstrated a malignant mesenchymal neoplasm that was positive for CD10, desmin, and vimentin and lacked expression of SMA, SMMH, synaptophysin, and chromogranin. AE1/AE3 highlighted rare foci. The patient underwent total hysterectomy with bilateral salpingo-oophorectomy. The hysterectomy specimen was notable for a 10.8 cm rubbery focally calcified tan- white mass histologically composed of high-grade spindle and epithelioid cells with hypocellular and hyalinized areas. The mitotic activity was &amp;gt;25/10HPF. Immunohistochemically, the neoplastic cells expressed CD10, caldesmon, desmin (patchy), SMA (weak focal), and CAM5.2 (patchy) while they were negative for ER, PR, HMB45, AE1/AE3, WT1, cyclin D1, BCOR, myogenin, pan-NTRK, and ALK. P53 staining showed a wild type expression pattern. Histology and immunohistochemistry could not definitively differentiate between leiomyosarcoma and high grade endometrial stromal sarcoma. RNA sequencing identified a RAB2A-PLAG1 gene fusion. In light of the histology and ancillary studies, a diagnosis of leiomyosarcoma was rendered. Results (if a Case Study enter NA) NA Conclusion This is the first case of a uterine leiomyosarcoma with RAB2A-PLAG1 gene fusion. Pathologists should be cognizant of the extensive morphologic and immunophenotypic overlap between various uterine mesenchymal neoplasms. In challenging cases, molecular analysis is crucial in allowing the pathologist to arrive at the final diagnosis.

Clinical characteristics and prognosis analysis of uterine sarcoma: a single-institution retrospective study

BackgroundUterine sarcomas are rare and aggressive gynaecologic malignancies, characterized by a relatively high recurrence rate and poor prognosis. The aim of this study was to investigate the clinicopathological features and explore the prognostic factors of these malignancies.MethodsThis was a single-institution, retrospective study. We reviewed the medical records of 155 patients with pathologically confirmed uterine sarcomas including uterine leiomyosarcoma (ULMS), low-grade endometrial stromal sarcoma (LG-ESS), high-grade endometrial stromal sarcoma (HG-ESS), undifferentiated uterine sarcoma (UUS) and adenosarcoma (AS) between 2006 and 2022. A total of 112 patients who underwent surgery between January 2006 and April 2019 were included in the survival analysis. The current study recorded the clinicopathological, treatment and outcome data to determine clinical characteristics and survival.ResultsThe most common histopathological type was ULMS (63/155, 40.64%), followed by LG-ESS (56/155, 36.13%) and HG-ESS (16/155, 10.32%). The mean age at diagnosis of all patients was 49.27±48.50 years and 32.90% (51/155) of patients were postmenopausal. Fifteen patients underwent fast-frozen sectioning, 63(54.78%) were diagnosed with malignancy, 29(25.22%) were highly suspected of malignancy that needed further clarification and 23(14.84%) were diagnosed with benign disease. A total of 124(80%) patients underwent total hysterectomy (TH) and salpingo-oophorectomy. Multivariate analyses showed that histological type and tumour size were independent prognostic factors both for overall survival (OS) (p<0.001 and P=0.017, respectively) and progression-free survival (PFS) (p<0.001 and P=0.018, respectively). Tumour stage was only significantly associated with PFS (P=0.002). Elevated preoperative NLR, PLR and postmenopausal status were significantly correlated with shorter PFS and OS in univariate analysis, but no statistically significant difference was found in multivariate analysis.ConclusionsIn patients with uterine sarcoma, in comparison to LMS and LG-ESS, UUS and HG-ESS tend to present as more aggressive tumour with poorer outcomes. Furthermore, larger tumour (>7.5 cm) were an important predictor of shorter PFS and OS.

A rare case of high-grade endometrial stromal sarcoma initially misdiagnosed as a uterine fibroid in a postmenopausal woman

Introduction: High-grade endometrial stromal sarcoma (HG-ESS) is a rare and aggressive malignant neoplasm that has a poor prognosis and accounts for 0.2% of uterine malignancies. There is a lack of available information on HG-ESS due to its high case fatality rate. Due to the poor prognosis associated with HG-ESS, it is important to diagnose HG-ESS in its early stages. Case Report: In this case report, we describe the case of a 63-year-old postmenopausal woman who presented with a pelvic mass and postmenopausal bleeding. The patient’s past history included a fibroid for which the patient underwent a successful uterine fibroid embolization. The patient underwent a pelvic ultrasound and an endometrial biopsy prior to gynecological consult. Both were inconclusive and led to an initial diagnosis of a uterine fibroid. After a gynecological consult and an additional biopsy, pathological examination revealed high-grade neoplastic cells that expressed strong and diffuse nuclear BCL1/Cyclin D1. The pattern of diffuse cyclin D1 expression and negative CD10 was suggestive of the YWHAE-rearranged subtype of HG-ESS. The combined morphologic and immunophenotypic features were consistent with a high-grade endometrial stromal sarcoma with fluorescence in situ hybridization (FISH) positivity for YWHAE gene rearrangement and FISH negativity for BCOR gene rearrangement. The patient underwent a robotic-assisted modified radical hysterectomy, radical pelvic tumor resection, bilateral salpingo-oophorectomy, sentinel pelvic lymph node dissections, and an appendectomy. The resulting surgical pathologic diagnosis was HG-ESS stage 1. Currently, no adjuvant therapy is recommended given negative margins with stage 1 status. Conclusion: High-grade endometrial stromal sarcoma is a rare clinical entity in postmenopausal women which is initially misdiagnosed but should be included in the differential diagnosis of necrotic masses.

Fertility-Sparing Management May Be Considered in Young Women with Uterine Sarcoma.

Uterine sarcomas occur very rarely in young women. Hysterectomy, which is a standard treatment, may not be acceptable for those patients, especially nulliparous women. Fertility-sparing management may be an alternative. The aim of the study was to assess fertility-sparing management in patients with uterine sarcoma. Eleven patients were eligible for the study. Histopathologic types of the tumor included: adenosarcoma (n = 3), low-grade endometrial stromal sarcoma (n = 3), low-grade myofibroblastic sarcoma (n = 1), leiomyosarcoma (n = 1), leiomyosarcoma myxoides (n = 1), rhabdomyosarcoma (n = 1), high grade endometrial stromal sarcoma (n = 1). The mean age of the patients at the time of diagnosis was 27.4 years (range: 17–35) and the average follow-up 61 months (range: 12–158). Six patients received adjuvant treatment: megestrol (n = 5) and chemotherapy (n = 1). Recurrence was diagnosed in five cases. Median time to recurrence was 35 months (range: 8–90). Three patients conceived spontaneously following treatment and gave at least one live birth. In total, five full-term pregnancies were recorded and five healthy children were born. Fertility-sparing management may be considered in some patients with uterine sarcoma; however, it may not be appropriate in high-grade endometrial stromal sarcoma. Patients with adenosarcoma may have a low chance of childbearing.

An Unusual Benign Uterine Stromal Spindle Cell Tumor Harboring JAZF1::BCORL1.

Uterine mesenchymal lesions demonstrate various underlying genomic alterations involving MED12 , JAZF1 , YWHAE , BCOR , and ALK genes, among others. Recent publications describe a subset of high-grade endometrial stromal sarcoma lesions harboring BCORL1 gene aberrations including JAZF1::BCORL1 . Herein, we present an unusual benign endomyometrial spindle cell lesion that defies classificatory efforts by demonstrating mixed histomorphologic and immunohistochemical features of endometrial stromal nodule, leiomyoma, and uterine inflammatory myofibroblastic tumor while harboring a JAZF1::BCORL1 . The lesion was found in a 43-yr-old woman with pelvic pain and heavy menses as a 5.5cm well-circumscribed ulcerated mass fungating from the cervical os. Microscopic examination revealed a polypoid, well-circumscribed, moderately cellular endomyometrial tumor composed by bland spindle cells haphazardly disposed within a slightly edematous stroma enriched by a delicate network of thin-walled vessels that were occasionally encircled by the tumor cells. Unequivocal evidence of tongue-like growth pattern into the myometrium, tumor-type necrosis or increased mitotic activity was not identified after sampling the entire lesion. The lesion showed patchy immunoreactivity for both smooth muscle actin-alpha and desmin while negative for CD10, HMB45, ALK (D5F3), and BCOR. An Archer FusionPlex panel assay demonstrated a fusion involving both exons 4 from the JAZF1 and BCORL1 genes. The JAZF1::BCORL1 has not, to the best of our knowledge, been previously reported in a benign/low-grade mesenchymal uterine lesion.

ETMR-03. Intra- and extra-cranial BCOR-ITD tumours are separate entities within the BCOR-rearranged family

BCOR-ITD tumours form an emerging family of aggressive entities with an internal tandem duplication (ITD) in the last exon of the BCOR gene. The family includes cerebral tumours, termed central nervous system BCOR-ITD (CNS BCOR-ITD), and sarcomatous types described in the kidney as clear cell sarcoma of the kidney (CCSK), in the endometrium as high-grade endometrial stromal sarcoma (HG-ESS), in bone, and in soft tissue as undifferentiated round cell sarcoma (URCS) or primitive myxoid mesenchymal tumour of infancy (PMMTI). Based on a series of 33 retrospective cases, including 10 CNS BCOR-ITD and 23 BCOR-ITD sarcomas, we interrogated the homogeneity of the entity regarding clinical, radiological and histopathological findings, and molecular signatures. Whole transcriptomic sequencing and DNA methylation profiling were used for unsupervised clustering. Histopathological review revealed marked differences between CNS BCOR-ITD and BCOR-ITD sarcomas. These two groups were consistently segregated by unsupervised clustering of expression (n=22) and DNA methylation (n=21) data. Proximity between the two groups may result from common somatic changes within key pathways directly related to the novel activity of the ITD itself. Conversely, comparison of gene signatures with single-cell RNAseq atlases suggests that the distinction between BCOR-ITD sarcomas and CNS BCOR-ITD may result from differences in cells of origin.

High-grade endometrial stromal sarcoma: A case report

Background: High-grade endometrial stromal sarcoma (HG-ESS) is a homologous uterine sarcoma of a mesenchymal origin. Its natural course is poorly understood, making preoperative diagnosis difficult.&#x0D; Case presentation: A 55-year-old nulliparous presented to the gynecological oncology ward as a referral with progressive abdominal distension and pain, constipation, and postprandial vomiting. Computed tomography (CT) scan of the abdomen revealed a bulky uterus with multiple calcified masses with cystic degeneration. A chest CT scan revealed bilateral upper and lower lobe nodules with mediastinum and hilar adenopathy. She was scheduled for total abdominal hysterectomy and bilateral salpingo-oophorectomy. A histopathological examination confirmed HG-ESS. The patient survived for three months following surgery.&#x0D; Conclusion: HG-ESS is rare. This case highlights the nonspecific presentation, aggressive nature of the tumor, rapid progression of the disease, and the challenges clinicians face in managing patients who do not honor their appointments with resultant poor overall survival in the late stage.

High-grade Endometrial Stromal Sarcoma: Morphologic and Clinical Features, the Role of Immunohistochemistry and Fluorescence in Situ Hybridization in Diagnosis.

Introduction. High-grade endometrial stromal sarcomas (HGESS) are rare malignant mesenchymal tumors of the uterus with aggressive poor clinical outcome, which frequently exhibit YWHAE::NUTM2 and ZC3H7B::BCOR fusions. In this study, we aimed to investigate HGESSs with YWHAE and BCOR translocations through our archive materials, and to identify morphological, immunohistochemical and molecular features of these tumors. We also assessed the diagnostic value of BCOR immunohistochemistry (IHC) in HGESSs, low-grade endometrial stromal sarcomas (LGESS) and uterine leiomyosarcomas. Methods. One hundred fifty-one uterine sarcomas diagnosed between 2000-2019 were reevaluated, and tumors of 39 patients with specific features were included in the study. Fluorescence in situ hybridization (FISH) studies using YWHAE and BCOR break-apart probes and BCOR IHC were performed. BCOR IHC was also performed in 20 leiomyosarcomas and 19 LGESSs. Results. In six HGESSs, translocations involving YWHAE or BCOR were detected. Five tumors showed high-grade morphology and revealed YWHAE translocation. One HGESS with myxoid morphology revealed BCOR translocation. In immunohistochemistry, three (3/4) YWHAE translocated HGESSs showed BCOR expression. However, the BCOR translocated HGESS was BCOR negative. The study showed that all LGESSs were immunohistochemically negative with BCOR. Although 15% (3/20) leiomyosarcomas reveal focal weak-moderate BCOR expression. Conclusion. BCOR IHC is a useful marker to distinguish LGESS from HGESS. A small percentage of uterine leiomyosarcomas reveal BCOR expression; however, it is not as diffuse and strong as in HGESSs. Strong and diffuse BCOR IHC expression is highly suggestive for HGESS. The diagnosis of HGESS should be supported by molecular studies such as FISH.

Soft Tissue and Visceral Organ Sarcomas With BCOR Alterations.

Sarcomas with BCOR alteration are a heterogenous group characterized by changes including internal tandem duplications (ITDs) and recurring fusions with CCNB3, ZC3H7B, and other rare partners. With widespread genomic testing, these alterations are now associated with histologies such as Ewing-like sarcoma (BCOR::CCNB3), high-grade endometrial stromal sarcoma (ZC3H7B::BCOR), and clear cell sarcoma of kidney (BCOR-ITD). BCOR altered sarcomas of soft tissues and organs were identified through PubMed using keywords "Sarcoma (AND) BCOR" from 2005 through October 2021. Summary statistics and outcome data were calculated using STATA v12.1. Forty-one publications described 190 patients with BCOR altered soft tissue or organ sarcomas. BCOR-ITD was most common, followed by BCOR::CCNB3, ZC3H7B::BCOR. BCOR-ITD tumors occurred mainly in infants, BCOR::CCNB3 commonly occurred in adolescent young adults, and ZC3H7B::BCOR only in adults. The most common site for BCOR::CCNB3 fused tumors was extremity, BCOR-ITD kidney and ZC3H7B::BCOR uterus. Metastasis was rare in patients with BCOR::CCNB3. While most underwent resection and chemotherapy, few received radiation. Median follow-up of survivors was 24 months. Five year overall survival for patients with BCOR::CCNB3 fusions was 68% (95% confidence interval [CI]: 46%-83%). Patients with BCOR-ITD and ZC3H7B::BCOR had worse prognoses with 5 years overall survival of 35% (95% CI: 15%-56%) and 41% (95% CI: 11%-71%), respectively, demonstrating need for collaborative efforts identifying optimal treatments to improve outcomes.

Endometrial Stromal Sarcomas With BCOR Internal Tandem Duplication and Variant BCOR/BCORL1 Rearrangements Resemble High-grade Endometrial Stromal Sarcomas With Recurrent CDK4 Pathway Alterations and MDM2 Amplifications.

The distinction between low-grade and high-grade endometrial stromal sarcomas (LGESS, HGESS) is increasingly defined by genetics. Recently, variant genomic alterations involving BCOR or BCORL1 have been reported in endometrial stromal sarcoma (ESS), although it remains unclear whether these justify a diagnosis of LGESS or HGESS. In this study, we describe clinicopathologic and molecular features of ESS with such alterations to help clarify their classification in the spectrum of ESS. We collected a cohort of 13 ESS harboring variant alteration involving BCOR (6 with internal tandem duplication, 1 with EP300::BCOR fusion, 1 with BCOR::LPP fusion) and BCORL1 ( 4 with JAZF1::BCORL1 fusion, 1 with EPC1::BCORL1 fusion). The median patient age at primary diagnosis was 51 years (range: 18 to 70 y). Median tumor size at primary diagnosis was 9.3 cm (range: 4.5 to 21 cm), and extrauterine disease spread (stage IIIB-C) was present in 27%. The tumors were composed of round to spindled cells with cellularity and cytologic atypia ranging from mild to marked and a median mitotic count of 18/10 HPFs (range: 2 to 85/10 HPFs). At least focally myopermeative growth was noted in 8/8 assessable cases. Of 12 patients with follow-up data (median: 25 mo), 4 patients died of disease and 3 were alive with recurrent disease. Unsupervised hierarchical clustering of DNA methylation data together with a large cohort of uterine mesenchymal tumors that included YWHAE::NUTM2 and Z C3H7B::BCOR HGESS and molecularly confirmed LGESS revealed a common methylation signature for all ESS with variant BCOR and BCORL1 alterations and HGESS with YWHAE::NUTM2 and ZC3H7B::BCOR gene fusion. Copy number analysis revealed amplifications of CDK4 and MDM2 , as well as homozygous deletions of CDKN2A/B and NF1 in a subset of tumors. Our results indicate that ESS with BCOR internal tandem duplication and variant BCOR and BCORL1 rearrangements clinically and molecularly resemble conventional HGESS.

Endometrial stromal tumors: Diagnostic updates and challenges.

Endometrial stromal tumors are rare uterine mesenchymal tumors of endometrial stromal origin. They are classified into endometrial stromal nodule, low-grade endometrial stromal sarcoma, high-grade endometrial stromal sarcoma, and undifferentiated uterine sarcoma by the current (2020) WHO classification. Correct diagnosis of endometrial stromal tumors is critical for proper patient management. However, due to infrequent encounters, overlapping morphological features and immunohistochemical profiles, the differential diagnoses among endometrial stromal lesions and their morphologic mimics are often challenging. Partially with our own experience, here we review and summarize the tumor morphology, immunohistochemical phenotype, as well as molecular feature of endometrial stromal tumors and key differential diagnoses, emphasizing the newest developments and their utilization in daily practice.