Recurrent chromosomal translocations in sarcomas create a megacomplex that mislocalizes NuA4/TIP60 to Polycomb target loci.

Chromosomal translocations frequently promote carcinogenesis by producing gain-of-function fusion proteins. Recent studies have identified highly recurrent chromosomal translocations in patients with endometrial stromal sarcomas (ESSs) and ossifying fibromyxoid tumors (OFMTs), leading to an in-frame fusion of PHF1 (PCL1) to six different subunits of the NuA4/TIP60 complex. While NuA4/TIP60 is a coactivator that acetylates chromatin and loads the H2A.Z histone variant, PHF1 is part of the Polycomb repressive complex 2 (PRC2) linked to transcriptional repression of key developmental genes through methylation of histone H3 on lysine 27. In this study, we characterize the fusion protein produced by the EPC1-PHF1 translocation. The chimeric protein assembles a megacomplex harboring both NuA4/TIP60 and PRC2 activities and leads to mislocalization of chromatin marks in the genome, in particular over an entire topologically associating domain including part of the HOXD cluster. This is linked to aberrant gene expression-most notably increased expression of PRC2 target genes. Furthermore, we show that JAZF1-implicated with a PRC2 component in the most frequent translocation in ESSs, JAZF1-SUZ12-is a potent transcription activator that physically associates with NuA4/TIP60, its fusion creating outcomes similar to those of EPC1-PHF1 Importantly, the specific increased expression of PRC2 targets/HOX genes was also confirmed with ESS patient samples. Altogether, these results indicate that most chromosomal translocations linked to these sarcomas use the same molecular oncogenic mechanism through a physical merge of NuA4/TIP60 and PRC2 complexes, leading to mislocalization of histone marks and aberrant Polycomb target gene expression.

Genetic variation of YWHAE gene-"Switch" of disease control. / YWHAEåŸºå› é—ä¼ å˜å¼‚­­ç–¾ç— 控制"å¼€å ³".

YWHAE gene is located on chromosome 17p13.3, and its product 14-3-3epsilon protein belongs to 14-3-3 protein family. As a molecular scaffold, YWHAE participates in biological processes such as cell adhesion, cell cycle regulation, signal transduction and malignant transformation, and is closely related to many diseases. Overexpression of YWHAE in breast cancer can increase the ability of proliferation, migration and invasion of breast cancer cells. In gastric cancer, YWHAE acts as a negative regulator of MYC and CDC25B, which reduces their expression and inhibits the proliferation, migration, and invasion of gastric cancer cells, and enhances YWHAE-mediated transactivation of NF-κB through CagA. In colorectal cancer, YWHAE lncRNA, as a sponge molecule of miR-323a-3p and miR-532-5p, can compete for endogenous RNA through direct interaction with miR-323a-3p and miR-532-5p, thus up-regulating K-RAS/ERK/1/2 and PI3K-AKT signaling pathways and promoting the cell cycle progression of the colorectal cancer. YWHAE not only mediates tumorigenesis as a competitive endogenous RNA, but also affects gene expression through chromosome variation. For example, the FAM22B-YWHAE fusion gene caused by t(10; 17) (q22; p13) may be associated with the development of endometrial stromal sarcoma. At the same time, the fusion transcript of YWHAE and NUTM2B/E may also lead to the occurrence of endometrial stromal sarcoma. To understand the relationship between YWHAE, NUTM2A, and NUTM2B gene rearrangement/fusion and malignant tumor, YWHAE-FAM22 fusion gene/translocation and tumor, YWHAE gene polymorphism and mental illness, as well as the relationship between 17p13.3 region change and disease occurrence. It provides new idea and basis for understanding the effect of YWHAE gene molecular mechanism and genetic variation on the disease progression, and for the targeted for the diseases.

Endometrial Stem/Progenitor cell (ES/PC) Marker Expression Profile in Adenosarcoma and Endometrial Stromal Sarcoma.

BACKGROUND: The uterus is one of the most dynamic organs in the human body, and this dynamic homeostasis is supported by endometrial stem/progenitor cells (ES/PCs), which are heterogeneous in their phenotype and degree of differentiation. ES/PCs are generally localized in the endometrial stroma, the site of origin for adenosarcoma and endometrial stromal sarcoma (ESS). Subsets of ESSs and adenosarcomas harbor SUZ12 or DICER1 gene alterations, two genes with roles in embryonic stem cell biology. However, the possible contribution of ES/PCs to tumorigenesis is unexplored. METHOD: We examined the expression of eleven ES/PC markers, along with three proteins expressed in the mature endometrial stroma (ER, PR and CD10) in 60 uterine tumors (24 low-, 11 high-grade ESS, 25 adenosarcomas). Protein expression profiles were assessed by unsupervised hierarchical clustering. miRNA expression profiles were examined in a subset of adenosarcoma with/without DICER1 mutations, using the NanoString platform. RESULTS: ES/PC markers were variably expressed, and the tumors exhibited limited immunophenotypic resemblance to different ES/PCs. Within the ESSs, the ES/PC marker clustering pattern was prognostic for both overall and disease-free survival. Comparing adenosarcomas and ESSs, most high-grade ESSs clustered with one another, while low-grade ESSs and adenosarcomas tended to cluster with one another. Among the adenosarcomas, the miRNA expression profiles were varied with respect to the DICER1 mutation status, with pathway analysis pointing to dysregulated signal transduction and stem cell biology. CONCLUSIONS: ESSs and adenosarcomas exhibit varying immunophenotypic resemblance to ES/PCs. These expression profiles have prognostic implications and may be genetically driven.

Molecular pathogenesis and prognostication of "low-grade'' and "high-grade" endometrial stromal sarcoma.

Endometrial stromal sarcomas (ESS) are a heterogeneous group of rare mesenchymal cancers. Considerable knowledge has been gained in recent years about the molecular characteristics of these cancers, which helps to classify them in a more meaningful manner leading to improved diagnosis, prognostication, and treatment. According to this classification, ESS is now grouped as low- or high-grade. ESS may have overlapping clinical presentation, morphology, and immunohistochemical profile. Their genetic characteristics allow subdivision of many of them depending on which pathogenetically important fusion genes they carry, but clearly much more needs to be unraveled in this regard. We here provide an overview of the molecular pathogenetic knowledge gained so far on low- and high-grade ESS.

NTRK and other recently described kinase fusion positive uterine sarcomas: A review of a group of rare neoplasms.

The landscape of uterine sarcomas has greatly expanded in recent years to include neoplasms with recurrent gene fusions, such as BCOR and YWHAE translocated high-grade endometrial stromal sarcomas. Sophisticated molecular techniques have also resulted in the description of "new" entities associated with recurrent kinase fusions involving NTRK and RET as well as COL1A1-PDGFB rearranged uterine sarcomas. These rare neoplasms will be discussed in this review, highlighting that some of the underlying molecular events are clinically actionable and potentially susceptible to targeted therapy. While relatively few of these neoplasms have been described to date, likely being previously lumped under the spectrum of undifferentiated uterine sarcoma, the number of cases will expand in the future given their recognition and the increasing availability of molecular testing. These neoplasms have overlapping morphology (often with a "fibrosarcoma-like" appearance) and immunohistochemical features, and are characterized by variable clinical outcomes. Although immunohistochemistry may assist in some cases, a definitive subclassification requires confirmatory molecular studies. As these molecular assays may not be routinely available in most laboratories, referral to reference centers may be needed. In order to assist the pathologist, we suggest a diagnostic algorithm for routine practice when dealing with a malignant or potentially malignant uterine spindle cell neoplasm.

BCOR Expression in Mullerian Adenosarcoma: A Potential Diagnostic Pitfall.

Adenosarcoma can mimic high-grade endometrial stromal sarcoma with ZC3H7B-BCOR fusion that may show entrapped glands and often exhibits diffuse BCOR expression. We encountered diffuse BCOR expression in rare adenosarcomas and sought to define its frequency among a larger cohort of these tumors. BCOR immunohistochemistry was performed on archival formalin-fixed paraffin-embedded tumor tissue in 13 of 14 adenosarcomas with and without stromal overgrowth arising in the uterus or ovary. The staining intensity and percentage of positive tumor nuclei in the mesenchymal component were evaluated. Eleven cases with sufficient tumoral tissue were subjected to fluorescence in situ hybridization for the detection of BCOR, BCORL1, NUTM1, ZC3H7B, and JAZF1 rearrangement. Three cases were subjected to targeted RNA sequencing. BCOR was expressed in 9 of 13 (70%) tumors, including 6 with and 3 without stromal overgrowth. Moderate to strong staining in >70% of cells was seen throughout in 1 low-grade and 6 high-grade tumors, 5 of which had stromal overgrowth. No staining was seen in 3 low-grade and 1 high-grade tumors with stromal overgrowth. One tumor demonstrating extensive sex cord-like differentiation and diffuse BCOR expression harbored JAZF1 and BCORL1 rearrangements. No BCOR or BCORL1 rearrangement was identified in the remaining tumors. BCOR expression is seen in most adenosarcomas with and without stromal overgrowth. BCORL1 rearrangement is seen in rare tumors with diffuse BCOR expression. Assessment of BCOR or BCORL1 rearrangement status is required in adenosarcomas demonstrating BCOR expression.

Retroperitoneal low grade endometrial stromal sarcoma with florid endometrioid glandular differentiation: Cytologic-histologic correlation and differential diagnosis.

Low grade endometrial stromal sarcoma (LGESS) is a rare neoplasm that typically arises in the uterine corpus and accounts for less than 1% of uterine sarcomas. Infrequently, extra-uterine LGESS can occur. Histologically, LGESS is characterized by a monotonous population of cells that resemble the proliferative phase of endometrial stroma and in their classic form they exhibit tongue-like growth pattern of infiltration and/or lymphovascular invasion. Infrequently LGESS can demonstrate various morphologic differentiation patterns, including endometrioid-type glands. We report the first fine needle aspiration (FNA) case of a periduodenal mass that was incidentally discovered on Computed Tomography (CT) scan of a 60-year-old female. The cytomorphologic and histologic findings and the immunohistochemical staining were consistent with a LGESS with endometrioid glandular differentiation. We are presenting the correlation between the cytologic, radiologic and pathologic features.

Immunohistochemical Expression of Different Subtypes of Cytokeratins by Endometrial Stromal Sarcoma.

Endometrial stromal sarcomas (ESS) are rare and understudied gynecologic mesenchymal neoplasms. These tumors can be confused with many other gynecologic and nongynecologic tumors due to their variegated morphologic appearance and nonspecific immunohistochemical profile. ESS can express cytokeratin (CK) and, therefore, may be misdiagnosed as carcinoma especially in extrauterine locations and when recurrence/metastasis is present. In this study, we investigated the expression of a wide spectrum of CKs consisting of AE1/3, CAM 5.2, HMCK, MNF116, CK5, CK6, CK7, CK8/18, CK14, CK17, CK19, and CK20 in 6 low-grade and 5 high-grade ESS. In addition, staining for estrogen receptor, progesterone receptor, CD10, and cyclin D1 was performed. Our results showed that CKs AE1/3, CAM 5.2, MNF116, and CK8/18 are more expressed in low-grade ESS, whereas high-grade ESS express more AE1/3 and CAM 5.2. In problematic cases, especially in recurrences or metastases, the immunohistochemical panel of antibodies AE1/3, MNF116, CAM 5.2, and CK8/18, together with other classic immunohistochemical markers CD10, cyclin D1, estrogen receptor, and progesterone receptor, may be helpful in the differential diagnosis between ESS and other gynecologic and nongynecologic malignancies.

YWHAE-NUTM2A/B Translocated High-grade Endometrial Stromal Sarcoma Commonly Expresses CD56 and CD99.

YWHAE-NUTM2A/B translocated high-grade endometrial stromal sarcoma is an uncommon and clinically aggressive uterine mesenchymal neoplasm which is sometimes associated with a low-grade fibromyxoid component. Although the diagnosis is confirmed using molecular techniques, it is possible to make the diagnosis based on the characteristic morphology and the immunophenotype; the latter typically includes diffuse positive staining of the high-grade component with cyclin D1 and CD117 and negative staining with CD10 and hormone receptors. Especially in a small biopsy specimen, in cases without a low-grade component or when presenting with extrauterine disease, the differential diagnosis may be wide and potentially include "small round cell tumors" such as a high-grade neuroendocrine carcinoma and a tumor in the Ewing family. In this study, we report consistent CD56 and CD99 immunoreactivity in YWHAE-NUTM2A/B translocated high-grade endometrial stromal sarcoma. We stained 20 of these neoplasms (10 molecularly confirmed and 10 where diagnosis was based on the morphology and immunophenotype) with CD56 and CD99; in one case, CD56 staining was not performed. Nineteen of 19 (100%) and 17 of 20 (85%) were positive with CD56 and CD99, respectively. Staining was usually diffuse with membranous and cytoplasmic immunoreactivity. Pathologists should be aware that YWHAE-NUTM2A/B translocated high-grade endometrial stromal sarcoma is commonly positive with CD56 and CD99; as well as potentially assisting in diagnosis, positivity with these markers may also result in consideration of other neoplasms in the differential diagnosis.

Aromatase inhibitor therapy for endometrial stromal sarcoma - two-centre experience.

OBJECTIVES: Endocrine therapy is the recommended systemic treatment for steroid receptor positive endometrial stromal sarcoma (ESS). There is no current consensus on the optimal hormonal therapy for ESS. The literature offers several reports on advanced/recurrent/metastatic ESS patients treated with progestins, whereas data on the efficacy of aromatase inhibitors are scarce. MATERIAL AND METHODS: We retrospectively identified cases treated for ESS with aromatase inhibitors at our institutions. There were five patients with advanced or unresectable recurrent estrogen, progesterone and androgen receptor-positive ESS, treated with aromatase inhibitors: letrozole or anastrozole (at a daily dose of 2.5 mg and 1 mg, respectively), as first-line endocrine therapy in all but one case treated following progression with megestrol acetate. RESULTS: Disease stabilization was achieved in four cases (80%), including two with long-term progression-free survival for up to 10 years attained under letrozole treatment, and one case after prior progestin treatment. During therapy, no substantial toxicity was observed. CONCLUSIONS: Aromatase inhibitors as first- or second-line endocrine treatment achieve disease control in most steroid receptor positive ESS. Our series of cases is evidence of aromatase inhibitors efficacy as long-term endocrine treatment option for ESS patients.

Endometrial Stromal Sarcoma Arising from Endometrial Polyp: A Case Report.

Endometrial stromal sarcoma (ESS) is a rare malignant tumor of the uterus. We report an uncommon case of ESS composed of both low-grade ESS and high-grade ESS arising from an endometrial polyp. On the findings of magnetic resonance imaging and contrast computed tomography, a patient was suspected of having uterine malignant tumor. She underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy. Macroscopically, the tumor was a polypoid lesion in the uterine cavity. The tumor was an endometrial polyp with ESS components. ESS was composed of low-grade ESS and high-grade ESS. By immunohistochemistry, both an endometrial polyp and low-grade ESS showed a positivity for CD10, estrogen receptor (ER), and progesterone receptor (PR). However, high-grade ESS showed only a focal and weak CD10 positivity with no immunostaining for ER and PR. A focal or diffuse positivity for α-smooth muscle actin and desmin was noted in both low-grade and high-grade ESS. The positive rates of Ki-67 and p53 in high-grade ESS were elevated up to over 95%. She was diagnosed as having ESS in a stage IA. After surgery, she received no further treatment. She has been without recurrence for 4 years since an initial surgery. In conclusion, immunohistochemical analyses are useful for make an accurate diagnosis of ESS showing a transition from low-grade ESS to high-grade ESS in addition to the conventional method.

Investigation of hormone receptor expression and its prognostic value in endometrial stromal sarcoma.

To evaluate the immunohistochemical (IHC) expression of hormone receptors and analyze the prognostic implication of these receptors in patients with endometrial stromal sarcoma (ESS). Fifty-one patients with ESS whose paraffin blocks and pathologic slides, which were obtained after hysterectomy, were available and included in this study. Clinicopathologic data were gathered from patients' medical records, and IHC staining of hormone receptors was performed using tissue microarrays. Estrogen receptor (ER)-alpha was expressed in 37 patients (72.5%), and strong immunoreactivity was observed in 27 patients (52.9%). However, ER-beta expression was observed in only two patients (3.9%). Progesterone receptor (PR) expression was identified in 36 patients (70.6%), and strong immunoreactivity was found in 26 patients (51%). Androgen receptor (AR) expression was observed in 30 patients (58.8%), and strong immunoreactivity was noted in 14 patients (27.5%). Gonadotropin-releasing hormone receptor (GnRH-R) expression was observed in 49 patients (96.1%), but no patient exhibited strong immunoreactivity. All patients expressed CYP19A1, and 43 patients (84.3%) had strong immunoreactivity. ER-alpha, PR, and AR positivity was associated with significantly better overall survival (OS). No patient with AR positivity died of ESS. When the patients were categorized according to ER-alpha, PR, and AR immunoreactivity, triple-positive ESS had the best OS, and triple-negative ESS was linked to the worst OS. Expression of hormone receptors was associated with favorable survival outcome in ESS. Hormone receptors that showed strong expression deserve further evaluation to clarify their importance as a therapeutic target and predictor of treatment response.

Gene expression profiling of low-grade endometrial stromal sarcoma indicates fusion protein-mediated activation of the Wnt signaling pathway.

OBJECTIVE: Low-grade endometrial stromal sarcomas (LGESS) harbor chromosomal translocations that affect proteins associated with chromatin remodeling Polycomb Repressive Complex 2 (PRC2), including SUZ12, PHF1 and EPC1. Roughly half of LGESS also demonstrate nuclear accumulation of ß-catenin, which is a hallmark of Wnt signaling activation. However, the targets affected by the fusion proteins and the role of Wnt signaling in the pathogenesis of these tumors remain largely unknown. METHODS: Here we report the results of a meta-analysis of three independent gene expression profiling studies on LGESS and immunohistochemical evaluation of nuclear expression of ß-catenin and Lef1 in 112 uterine sarcoma specimens obtained from 20 LGESS and 89 LMS patients. RESULTS: Our results demonstrate that 143 out of 310 genes overexpressed in LGESS are known to be directly regulated by SUZ12. In addition, our gene expression meta-analysis shows activation of multiple genes implicated in Wnt signaling. We further emphasize the role of the Wnt signaling pathway by demonstrating concordant nuclear expression of ß-catenin and Lef1 in 7/16 LGESS. CONCLUSIONS: Based on our findings, we suggest that LGESS-specific fusion proteins disrupt the repressive function of the PRC2 complex similar to the mechanism seen in synovial sarcoma, where the SS18-SSX fusion proteins disrupt the mSWI/SNF (BAF) chromatin remodeling complex. We propose that these fusion proteins in LGESS contribute to overexpression of Wnt ligands with subsequent activation of Wnt signaling pathway and formation of an active ß-catenin/Lef1 transcriptional complex. These observations could lead to novel therapeutic approaches that focus on the Wnt pathway in LGESS.

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

OBJECTIVE: This study aimed to investigate the conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) features of endometrial stromal sarcoma (ESS) including a preliminary investigation of the correlation between the apparent diffusion coefficient (ADC) value and Ki-67 expression. METHODS: The clinical and MRI data of 15 patients with ESS confirmed by surgery and pathology were analyzed retrospectively. The conventional MR morphological features, signal intensity on DWI, ADC value (n = 14), and clinicopathological marker Ki-67 (n = 13) were evaluated. RESULTS: Of 15 patients with ESS, 13 tumors were low-grade ESS (LGESS), and the remaining 2 were high-grade ESS (HGESS); 9 tumors were located in the myometrium, 5 were located in the endometrium and/or cervical canal, and 1 was located in extrauterine. Thirteen (87%) of 15 tumors showed a homo- or heterogeneous isointensity on T1-weighted imaging and a heterogeneous hyperintensity on T2-weighted imaging. The hypointense bands were observed in 11 tumors (73%) on T2-weighted imaging. The degenerations (cystic/necrosis/hemorrhage) were observed in 7 LGESS tumors and 2 HGESS tumors. The DWI hyperintensity was observed in 13 tumors (93%) and isointensity in remaining 1. The mean ADC value of the solid components in 14 ESSs was (1.05 ± 0.20) × 10mm/s. The contrast-enhanced MRI showed an obvious enhancement in 14 tumors (93%) (heterogeneous in 7 LGESSs and 2 HGESSs; homogeneous in 5 LGESSs). The ADC value was inversely correlated with the Ki-67 expression (r = -0.613, P = 0.026). CONCLUSIONS: Patients with ESS showed some characteristics on conventional MRI and DWI, and there was an inverse correlation between the ADC value and Ki-67 expression.

Molecular characteristics of uterine sarcomas.

INTRODUCTION: Uterine sarcomas are rare cancers, of which the most common entities are leiomyosarcoma and endometrial stromal sarcoma. These two tumors may have overlapping clinical presentation, morphology and immunohistochemical profile, but are increasingly recognized to be two molecularly distinct entities. Endometrial stromal sarcomas are further currently divided into a low-grade and high-grade group based on molecular characteristics. Area covered: This review discusses recent data which shed light on the molecular profile of these two cancers and may aid in understanding their evolution and progression, in the aim of improving their diagnosis and management. Search was through PubMed, with focus on studies published in the last 5 years. Expert commentary: The literature presented and discussed documents rapidly expanding knowledge of the genetic characteristics of leiomyosarcoma and endometrial stromal sarcoma, with an array of molecules and pathways implicated in the biology of these cancers. Several of these molecules are potential therapeutic targets. Assessment of their predictive and prognostic role awaits larger studies.

Androgen Receptor Expression in Endometrial Stromal Sarcoma: Correlation With Clinicopathologic Features.

Endometrial stromal sarcoma (ESS) is a rare neoplasm comprising only 0.2% to 1% of all uterine malignancies and occurs in women between 42 and 59 yr of age. ESSs frequently express estrogen receptor (ER) and progesterone receptor (PR). However, the published literature contains scant data on the expression and therapeutic/prognostic role of androgen receptor (AR) in ESSs. We undertook this study to characterize the expression of AR along with ER and PR in ESSs and correlate it with clinicopathologic features. The clinical details, slides, and blocks of 25 tumors from 24 patients (September 2010 to February 2016) were retrieved. The diagnosis and grade of ESS were reviewed and immunohistochemistry performed with anti-ER, PR, and AR antibodies. Ages ranged from 18 to 50 yr, with a mean age of 36 yr. Low-grade ESS (LGESS) and high-grade ESS (HGESS) were diagnosed in 15 and 9 patients, respectively. An 18-yr-old woman who initially had LGESS suffered a pelvic recurrence; that exhibited high-grade morphology. Our patients, especially those with HGESS, were much younger compared with published worldwide data. ER, PR, and AR immunoreactivity was observed in 14 (93.3%), 12 (80%), and 11 (73.3%) LGESSs, respectively. This is in contrast to HGESSs, in which 5 (50%) tumors had a triple-negative hormonal profile. AR, like ER and PR, was more frequently expressed in LGESS as compared with HGESS. Whether AR, in addition to ER and PR receptor status, may help guide adjuvant hormonal therapy needs further elucidation.

Immunohistochemical Characterization of Histone Deacetylase as a Potential Prognostic Marker and Therapeutic Target in Endometrial Stromal Sarcoma.

AIM: Endometrial stromal sarcoma (ESS) is a rare tumor with limited treatment options. Histone deacetylase (HDAC) is a potential therapeutic target in ESS showing a good rate of response in laboratory studies. In this study we investigated the expression of HDAC enzymes in 41 ESS patients. MATERIALS AND METHODS: Immunohistochemical expression of HDACs was analyzed by tissue microarrays. RESULTS: Strong positive immunoreactivity was observed in 32 (78.0%), 23 (56.1%), 8 (19.5%), 36 (87.8%), 7 (17.1%), 30 (73.2%), 31 (75.6%), and 33 (80.5%) for HDACs 1-8, respectively. Although not statistically significant, HDAC 1, 4, 6, 7, and 8 exhibited a high frequency of strong immunoreactivity linked to a lower 10-year DFS (100.0% vs. 81.3%, p=0.202; 100.0% vs. 83.3%, p=0.393; 90.9% vs. 83.3%, p=0.579; 90.0% vs. 83.9%; and 100.0% vs. 81.8%, p=0.207; respectively). CONCLUSION: HDACs 1, 4, 6, 7, and 8, that showed an especially high frequency of strong immunoreactivity, may represent potential therapeutic targets for ESS.

Immunohistochemical panel to differentiate endometrial stromal sarcoma, uterine leiomyosarcoma and leiomyoma: something old and something new.

AIMS: To evaluate an immunohistochemical panel differentiating endometrial stromal sarcoma (ESS) from uterine leiomyosarcoma (ULMS) and leiomyoma (LM). METHODS: 94 cases (28 ESS, 41 ULMS, 25 LM) were retrieved and arrayed. 10 immunomarkers (estrogen receptor (ER), progesterone receptor (PR), CD10, smooth muscle actin, desmin, h-caldesmon, transgelin, GEM, ASC1, stathmin1) were used. A predictive model was constructed and examined by receiver operating characteristics curve analysis to determine area under the curve (AUC). RESULTS: The combination of ER(+)/PR(+)/CD10(+)/GEM(-)/h-caldesmon(-)/transgelin(-) can predict ESS versus ULMS with AUC predictive value of 0.872 (95% CI 0.784 to 0.961, p<0.0001). The combination of ER(+)/PR(+)/CD10(+)/h-caldesmon(-)/transgelin(-) can predict low grade (LG) ESS from 'LG' ULMS with AUC predictive value of 0.914 (95% CI 0.832 to 0.995, p<0.0001). Finally, ULMS and ESS, including the LGs, were more likely to be stathmin1(+) than LM. CONCLUSIONS: Due to the different clinical course and management, adding novel antibodies (GEM, transgelin) to the well established immunohistochemistry panel seemed to be useful in distinguishing ESS from ULMS and LG ESS from 'LG' ULMS. Finally, stathmin1 expression could be of value in differentiating LM from uterine sarcomas.

Molecular characterization of a population-based series of endometrial stromal sarcomas in Kuwait.

Endometrial stromal sarcomas (ESSs) frequently harbor genetic fusions, including JAZF1-SUZ12 and equivalent fusions in low-grade ESS (LGESS) and YWHAE-NUTM2 in high-grade ESS (HGESS). This study aims to classify a population-based series of ESSs in Kuwait based on the 2014 World Health Organization classification system and to assess the diagnostic use of interferon-induced transmembrane protein 1 (IFITM1) immunomarker for ESSs. Twenty ESSs including 19 LGESSs and 1 HGESS treated during the period between 2002 and 2013 were identified, and the cases were reviewed and characterized using fluorescence in situ hybridization and immunohistochemical studies. Thirteen (81.3%) of 16 LGESSs with interpretable results showed JAZF1 and/or PHF1 genetic rearrangements by fluorescence in situ hybridization, and the only HGESS in the series showed YWHAE genetic rearrangement. All LGESSs with interpretable results showed positive immunostaining for CD10 compared with 11 (61%) of 18 that showed positive immunostaining for IFITM1; 4 of 7 IFITM1-negative LGESSs showed JAZF1 and/or PHF1 rearrangements. A series of uterine leiomyomas, leiomyosarcomas, adenosarcomas, and carcinosarcomas were included for comparison, and positive IFITM1 staining was found in 1 of 10 leiomyomas, 3 of 13 leiomyosarcomas, 3 of 4 adenosarcomas, and 3 of 8 carcinosarcomas, compared to 0 of 10 leiomyomas, 9 of 13 leiomyosarcomas, 3 of 4 adenosarcomas, and 5 of 8 carcinosarcomas that were positive for CD10. Our results demonstrated characteristic genetic rearrangements in a high percentage of LGESSs in this Middle Eastern population, and IFITM1 antibody appears to be less sensitive than CD10 for LGESS.