Low-grade Endometrial Stromal Sarcoma Research Articles

The value of surgery and the prognostic factors for patients with recurrent low-grade endometrial stromal sarcoma: a retrospective study of 38 patients.

As an indolent malignant tumor, the long-term management of low-grade endometrial stromal sarcoma (LGESS) patients required awareness, especially the management of recurrences. Unfortunately, few studies focused on the treatment of recurrent LGESS. Our study aimed to investigate the prognostic factors and the value of recurrent surgery on recurrent LGESS. This retrospective study consecutively recruited patients with pathologically diagnosed recurrent LGESS at our center from April 1, 2004 to April 1, 2020. After a median follow-up of 137.0 months (95% confidence interval=85.4-188.6), the 5-year cumulative survival rate of the cohort of 38 patients with recurrent LGESS was 71.1%. The median overall survival (OS) and post-recurrence survival (PRS) was 156 and 89.0 months. Survival analysis showed that patients with younger age, positive estrogen receptor (ER) and optimal abdominopelvic debulking in the first recurrent surgery had better prognosis (p<0.05). Multivariate analysis showed that optimal abdominopelvic debulking in the first recurrent surgery was the only independent prognostic factor for OS and PRS (OS=216.0/35.0 months, hazard ratio [HR]=5.319, p=0.034; PRS=not reached/4.0 months, HR=10.900, p=0.006). There was no significant difference in OS and PRS between patients recurred only once and those recurred at least twice (p>0.05). The prognosis of recurrent LGESS was favorable. Optimal debulking of no residual tumor in abdominal and pelvic cavity should be the first choice of treatment for recurrent patients, while preservation of ovary or fertility should not be recommended.

Low-grade extrauterine endometrial stromal sarcoma arising from vaginal endometriosis: a case report and literature review.

Extrauterine endometrial stromal sarcoma arising from malignant transformation of the vagina is an extremely rare condition. The diagnosis is often difficult as the symptomatology and pathological features overlap with that of pelvic endometriosis. A 38 years old female presented with complaints of dyspareunia, dysmenorrhea, and painful defecation along with blood-stained vaginal discharge for a year. Examination revealed the presence of multiple brownish irregular nodules in posterior vaginal fornix and fixed tender nodules which on biopsy revealed florid vaginal endometriosis. She improved symptomatically on medical therapy. After 18 months of diagnosis, she presented again with a necrotic growth in posterior fornix, which on repeat biopsy revealed a low-grade endometrial stromal sarcoma. Laparotomy revealed a 7×5 cm mass in the pouch of Douglas, infiltrating the posterior vaginal wall and rectum. A complete cytoreductive surgery with retrograde hysterectomy, excision of posterior vaginal wall and rectosigmoid resection was done. The patient is disease-free at a follow-up of 65 months.

Endometrial stromal tumor presenting as multiple endometrial polyps with limited infiltration; a novel presentation

Abstract Introduction/Objective The 2020 WHO classifies endometrial stromal tumors into endometrial stromal nodule (ESN), low-grade endometrial stromal sarcoma (LGESS), high-grade endometrial stromal sarcoma, and undifferentiated sarcoma. Minimal irregularity of the interface is allowed in ESN (up to 3 foci of &amp;lt;3 mm). In a small number of cases, the irregular interface exceeds the acceptable criteria for ESN but relatively limited compared to most LGESS. These cases are classified as endometrial stromal tumor with limited infiltration. These tumors may recur, and it is best managed as LGESS. Methods/Case Report We report a case of endometrial stromal tumor in a 42-year-old female who presented with abnormal vaginal bleeding. Imaging showed multiple fibroids. She underwent total abdominal hysterectomy and bilateral salpingectomy. On gross examination three endometrial polyps with sharp demarcation from the adjacent myometrium were identified (largest 4 cm). Histology revealed proliferation of uniform small cells with scant cytoplasm and round to oval nuclei with rare mitotic figures in a delicate network of arterioles. Immunostains showed positive staining for CD10 and estrogen receptor while negative for Caldesmon. These polyps were mainly confined to the endometrium with only small foci of irregular border with the myometrium. No vascular invasion, high grade cytologic atypia or necrosis were seen. The tumor showed JAZF1-SUZ12 gene fusion. This case was diagnosed as an endometrial stromal tumor with limited infiltration. Results (if a Case Study enter NA) NA Conclusion In conclusion, endometrial stromal tumors are commonly submucosal or intramural, we report a rare case that presented as multiple endometrial polyps, with very limited myometrium infiltration. To our knowledge, no cases have been reported so far. It is essential to be cognizant of this entity when dealing with polypoid lesions of the endometrium, they may recur and should be managed as LGESS.

Pan-TRK immunohistochemistry in gynaecological mesenchymal tumours: diagnostic implications and pitfalls.

NTRK-rearranged sarcomas of the female genital tract mainly occur in the uterus (more commonly cervix than corpus) and are characterized by a "fibrosarcoma-like" morphology and NTRK gene rearrangements. These neoplasms may exhibit histological overlap with other entities and can present diagnostic difficulties without molecular confirmation. Pan-TRK immunohistochemistry was developed to identify tumours harbouring NTRK rearrangements. The aim of this study was to characterize pan-TRK immunohistochemical expression in a large cohort of gynaecological mesenchymal neoplasms and investigate the utility of pan-TRK immunohistochemistry todistinguish NTRK-rearranged sarcoma from its mimics. A total of 473 gynaecological mesenchymal tumours (461 without known NTRK fusions and 12 NTRK-rearranged sarcomas) were selected. Pan-TRK immunohistochemistry (EPR17341, Abcam) was performed on whole tissue sections and tissue microarrays. Molecular interrogation of pan-TRK positive tumours was performed by RNA sequencing or fluorescence in situ hybridization (FISH). Of the 12 NTRK-rearranged sarcomas, 11 (92%) exhibited diffuse (≥70%) cytoplasmic pan-TRK staining with moderate/marked intensity, while the other wasnegative. Eleven (2.4%) additional tumours also exhibited pan-TRK immunohistochemical expression: three low-grade endometrial stromal sarcomas, seven high-grade endometrial stromal sarcomas, and an undifferentiated uterine sarcoma. Molecular confirmation of the absence of NTRK rearrangements was possible in nine of these tumours. Of these nine neoplasms, seven exhibited focal/multifocal (<70%) pan-TRK cytoplasmic staining with weak/moderate intensity. Even though pan-TRK immunohistochemical expression is not entirely sensitive or specific for NTRK-rearranged sarcomas, these neoplasms tend to exhibit diffuse staining of moderate/strong intensity, unlike its mimics. Pan-TRK should be performed in monomorphic uterine (corpus and cervix) spindle cell neoplasms that are negative for smooth muscle markers and hormone receptors and positive for CD34 and/ or S100. Ultimately, the diagnosis requires molecular confirmation.

Targeted RNA Sequencing Highlights a Diverse Genomic and Morphologic Landscape in Low-grade Endometrial Stromal Sarcoma, Including Novel Fusion Genes.

Low-grade endometrial stromal sarcoma (LGESS) represents a morphologically and genetically heterogenous mesenchymal neoplasm. Previous work has shown that approximately half of LGESS are characterized by JAZF1::SUZ12 gene fusions, while a smaller proportion involves rearrangement of other genes. However, a subset of cases has no known genetic abnormalities. To better characterize the genomic landscape of LGESS, we interrogated a cohort with targeted RNA sequencing (RNA-Seq). Cases previously diagnosed as low-grade endometrial stromal neoplasia (n=51) were identified and re-reviewed for morphology and subjected to RNA-Seq, of which 47 were successfully sequenced. The median patient age was 49 years (range: 19 to 85). The most commonly detected fusions were JAZF1::SUZ12 (n=26, 55%) and BRD8::PHF1 (n=3, 6%). In addition to the usual/typical LGESS morphology, some JAZF1::SUZ12 fusion tumors showed other morphologies, including fibrous, smooth muscle, sex-cord differentiation, and myxoid change. Novel translocations were identified in 2 cases: MEAF6::PTGR2 and HCFC1::PHF1 . Ten tumors (21%) had no identifiable fusion, despite a similar morphology and immunophenotype to fusion-positive cases. This suggests that a subset of cases may be attributable to fusion products among genes that are not covered by the assay, or perhaps altogether different molecular mechanisms. In all, these findings confirm that RNA-Seq is a potentially useful ancillary test in the diagnosis of endometrial stromal neoplasms and highlight their diverse morphology.

Diagnostic des sarcomes utérins et tumeurs mésenchymateuses utérines rares à potentiel de malignité. Référentiels du Groupe Sarcome Français et des Tumeurs Rares Gynécologiques

The landscape of uterine sarcomas is becoming more complex with the description of new entities associated with recurrent driver molecular alterations. Uterine sarcomas, in analogy with soft tissue sarcomas, are distinguished into complex genomic and simple genomic sarcomas. Leiomyosarcomas and undifferentiated uterine sarcomas belong to complex genomic sarcomas group. Low-grade and high-grade endometrial stromal sarcomas, other rare tumors associated with fusion transcripts (such as NTRK, PDGFB, ALK, RET ROS1) and SMARCA4-deficient uterine sarcoma are considered simple genomic sarcomas. The most common uterine sarcoma are first leiomyosarcoma and secondly endometrial stromal sarcomas. Three different histological subtypes of leiomyosarcoma (fusiform, myxoid, epithelioid) are identified, myxoid and epithelioid leiomyosarcoma being more aggressive than fusiform leiomyosarcoma. The distinction between low-grade and high-grade endometrial stromal sarcoma is primarily morphological and immunohistochemical and the detection of fusion transcripts can help the diagnosis. Uterine PEComa is a rare tumor, which is distinguished into borderline and malignant, according to a risk assessment algorithm. Embryonal rhabdomyosarcoma of the uterine cervix is more common in children but can also occur in adult women. Embryonal rhabdomyosarcoma of the uterine cervix is almost always DICER1 mutated, unlike that of the vagina which is wild-type DICER1, and adenosarcoma which can be DICER1 mutated but with less frequency. Among the emerging entities, sarcomas associated with fusion transcripts involving the NTRK, ALK, PDGFB genes benefit from targeted therapy. The integration of molecular data with histology and clinical data allows better identification of uterine sarcomas in order to better treat them.

Next generation sequencing reveals a high prevalence of pathogenic mutations in homologous recombination DNA damage repair genes among patients with uterine sarcoma

ObjectiveInvestigate the incidence of homologous recombination DNA damage response (HR-DDR) genomic alterations among patients with uterine sarcoma. MethodsThe American Association for Cancer Research GENIE v13.0 database was accessed and patients with uterine leiomyosarcoma, adenosarcoma, undifferentiated uterine sarcoma, high-grade endometrial stromal sarcoma, low-grade endometrial stromal sarcoma, and endometrial stromal sarcoma not otherwise specified were identified. We determined the incidence of pathogenic alterations in the following genes involved in HR-DDR: ATM, ARID1A, ATRX, BAP1, BARD1, BLM, BRCA2, BRCA1, BRIP1, CHEK2, CHEK1, FANCA, FANCC, FANCD2, FANCE, FANCF, FANCG, FANCL, MRE11, NBN, PALB2, RAD50, RAD51, RAD51B, RAD51C, RAD51D, WRN. Data from the OncoKB database, as provided by cBioPortal, was utilized to determine the presence of pathogenic genomic alterations. ResultsA total of 509 patients contributing with 525 samples were identified. Median patient age at sample collection was 56 years while the majority were White (80.7%). The most common histologic subtype was leiomyosarcoma (63.8%) followed by adenosarcoma (12.3%). The overall incidence of HR-DDR genomic alterations was 28.2%. The most commonly altered genes were ATRX (18.2%), BRCA2 (4%), and RAD51B (2.6%). The highest incidence of HR-DDR genomic alterations was observed among patients with leiomyosarcoma (35.4%), adenosarcoma (27%) and undifferentiated uterine sarcoma (30%), while those with low-grade endometrial stromal sarcoma had the lowest (2.9%) incidence. ConclusionsApproximately 1 in 3 patients with uterine sarcoma harbor a pathogenic alteration in HR-DDR genes. Incidence is high among patients with uterine leiomyosarcoma and adenosarcoma.

Sarcoma estromal endometrial extrauterino primario de bajo grado

Endometriosis is a common benign lesion whose importance lies in the associated symptomatology and the possibility of malignant transformation. Endometrial stromal sarcoma is a rare tumor, accounting for only 0.2% of all female genital tract tumors. Primary extrauterine endometrial stromal sarcomas are even rarer, are frequently associated with endometriosis, and have been reported in the ovaries, fallopian tubes, pelvic cavity, abdominal cavity, and retroperitoneum in the absence of uterine pathology. We describe a case of a female patient who consulted for dysmenorrhea, dysuria, and dyschezia. Pelvic magnetic resonance showed a heterogeneous tumor in the left adnexa compatible with endometrioma. Histopathological findings and immunohistochemical staining were consistent with the diagnosis of primary low-grade extrauterine endometrial stromal sarcoma. The patient underwent total hysterectomy, bilateral oophorosalpingectomy, total omentectomy, and pelvic and para-aortic lymph node resection.

Clinical features of uterine sarcomas presenting mainly with uterine masses: a retrospective study

BackgroundUterine sarcomas are uncommon mesenchymal tumors of the uterus. The clinical problem is that the features of uterine sarcomas can sometimes mimic uterine fibroids. This study aims to investigate the clinical characteristics of patients with uterine sarcomas who were preoperative presenting mainly with uterine masses.MethodsA retrospective analysis of patients who underwent gynecological surgery for uterine sarcomas at the Obstetrics & Gynecology Hospital of Fudan University, between January 2016 and December 2021.ResultsOver the 5-year period, 277 patients were final diagnosed of uterine sarcomas. A total of 162 patients were preoperatively diagnosed as uterine fibroids for surgical treatment, the majority of whom were diagnosed of uterine leiomyosarcoma (uLMS) (49/162) and low-grade endometrial stromal sarcoma (LG-ESS) (100/162). Ninety people underwent total hysterectomy and bilateral salpingo-oophorectomy (TH + BSO), while 72 underwent myomectomy followed by supplemental TH + BSO. The group with direct hysterectomy had a higher average age than the group with prior myomectomy (47.20 ± 8.94 vs. 40.86 ± 5.88, p < 0.001). Among patients preoperatively diagnosed as uterine fibroids, patients with uLMS had a higher proportion of previous myomectomy (26.53% vs. 5.00%, p < 0.001), a larger uterine mass diameter on ultrasound (8.38 ± 3.39 cm vs. 6.41 ± 1.92 cm, p < 0.001), and richer hypervascularity (34.69% vs. 18%, p = 0.024) compared with LG-ESS.ConclusionsAnalysis of our data showed that a large proportion of uterine sarcomas, especially uLMS and LG-ESS, present mainly with uterine masses. Ultrasound features including a large uterine mass diameter and rich hypervascularity, and with a history of myomectomy may alert clinicians in suspicion of uLMS when compared with LG-ESS.

Metastatic Low-Grade Endometrial Stromal Sarcoma of Uterus Presenting as Urothelial Tumor: Case Report and Brief Review of Literature

Metastatic Low-Grade Endometrial Stromal Sarcoma of Uterus Presenting as Urothelial Tumor: Case Report and Brief Review of Literature

A Case of Uterine Tumor Resembling Ovarian Sex Cord Tumor With Prominent Myxoid Features.

Uterine tumor resembling ovarian sex cord tumor (UTROSCT) is a rare tumor with low malignant potential that commonly occurs in middle age. Although more than 100 cases have been reported to date, myxoid morphology is not well documented. Here, we present a 75-yr-old woman with abnormal vaginal bleeding, with an 8-cm mass in the uterine corpus detected by irregular, high-intensity signaling on T2-weighted imaging. The uterine mass had a glistening mucinous appearance on gross examination. Microscopically, most of the tumor cells were floating in the myxoid stroma. The tumor cells formed clusters or nests with abundant cytoplasm, while some exhibited trabecular or rhabdoid appearances. Immunohistochemically, tumor cells were positive for pancytokeratin (AE1/AE3), α-smooth muscle actin, CD10, progesterone receptor, and some sex cord markers such as calretinin, inhibin, CD56, steroidogenic factor-1. Electron microscopy demonstrated epithelial and sex cord differentiation. This tumor was negative for JAZF1-JJAZ1 fusion gene that is frequently found in low-grade endometrial stromal sarcoma. Fusion genes related to UTROSCT, including NCOA2/3, were not detected by reverse transcription polymerase chain reaction. The present case suggests that UTROSCT should be included in the differential diagnosis of myxoid uterine tumors.

The KAT6B::KANSL1 Fusion Defines a New Uterine Sarcoma With Hybrid Endometrial Stromal Tumor and Smooth Muscle Tumor Features

Neoplasms harboring a KAT6B/A::KANSL1 fusion were initially reported as benign (leiomyomas) and malignant (leiomyosarcomas, low-grade endometrial stromal sarcomas [LG-ESSs]) uterine neoplasms. However, they may represent an emerging entity characterized by clinical aggressiveness contrasting with a rather reassuring microscopic appearance. Here, we aimed to confirm that this neoplasm is a distinct clinicopathologic and molecular sarcoma and identify criteria that should alert pathologists and lead to KAT6B/A::KANSL1 fusion testing in routine practice. Therefore, we conducted a comprehensive clinical, histopathologic, immunohistochemical, and molecular study, including array comparative genomic hybridization, whole RNA-sequencing, unsupervised clustering, and cDNA mutational profile analyses of 16 tumors with KAT6B::KANSL1 fusion from 12 patients. At presentation, patients were peri-menopausal (median, 47.5 years), and the primary tumors were located in the uterine corpus (12/12, 100%), with an additional prevesical location in 1 (8.3%) of 12 cases. The relapse rate was 33.3% (3/9). All tumors (16/16, 100%) showed morphologic and immunohistochemical features overlapping between leiomyoma and endometrial stromal tumors. A whirling recurrent architecture (resembling fibromyxoid-ESS/fibrosarcoma) was found in 13 (81.3%) of 16 tumors. All tumors (16/16, 100%) exhibited numerous arterioliform vessels, and 13 (81.3%) of 18 had large hyalinized central vessels and collagen deposits. Estrogen and progesterone receptors were expressed in 16 (100%) of 16 and 14 (87.5%) of 16 tumors, respectively. Array comparative genomic hybridization performed on 10 tumors classified these neoplasms as simple genomic sarcomas. Whole RNA-sequencing on 16 samples and clustering analysis on primary tumors found that the KAT6B::KANSL1 fusion always occurred between exons 3 of KAT6B and 11 of KANSL1; no pathogenic variant was identified on cDNA, all neoplasms clustered together, close to LG-ESS, and pathway enrichment analysis showed cell proliferation and immune infiltrate recruitment pathway involvement. These results confirm that the sarcomas harboring a KAT6B/A::KANSL1 fusion represent a distinct clinicopathologic entity, close to LG-ESS but different, with clinical aggressiveness despite a reassuring morphology, for which the KAT6B/A::KANSL1 fusion is the molecular driver alteration.

Prognostic factors, oncological treatment and outcomes of uterine sarcoma: 10 years’ clinical experience from a tertiary care center in Pakistan

BackgroundUterine sarcoma is an uncommon aggressive malignancy. Optimal management and prognostic factors have yet to be well recognized due to their rarity and various histological subtypes. This study aims to investigate these patients' prognostic factors, treatment modalities, and oncological outcomes.MethodsA single-center retrospective cohort study was conducted on all patients diagnosed with uterine sarcoma and treated from January 2010 to December 2019 in a tertiary-care hospital in Pakistan. The data were analyzed using STATA software and stratified on the histological subtype. Survival rates were estimated using the Kaplan–Meier method. Crude and adjusted hazard ratios with 95% CI were estimated using univariate and multivariate analysis.ResultsOf the 40 patients, 16(40%) had uterine leiomyosarcoma (u-LMS), 10(25%) had high-grade endometrial stromal sarcoma (HGESS), 8(20%) had low-grade endometrial stromal sarcoma (LGESS) and 6(15%) had other histological subtypes. The median age of all patients was 49 (40–55.5). Thirty-seven (92.5%) patients underwent primary surgical resection, and 24 (60%) patients received adjuvant systemic chemotherapy. The survival plots showed the overall population's DFS of 64 months and the OS of 88 months (p-value = 0.001). The median DFS in all patients was 12 months, and the median OS was 14 months (p-value = 0.001). A small but significant DFS benefit was found in patients who received adjuvant systemic chemotherapy, 13.5 versus 11 months (p-value = 0.001). Multivariate Cox-regression analysis revealed that large tumor size and advanced FIGO stage were substantial factors associated with decreased survival.ConclusionUterine sarcomas are rare malignancies with poor prognosis. Multiple factors, including tumor size, mitotic count, stage of the disease, and myometrial invasion, impact survival outcomes. Adjuvant treatment may decrease the recurrence rate and improve DFS but do not affect OS.

Diagnostic utility of PRAME immunohistochemistry in PEComa family of tumors and morphologic mimics with emphasis on the gynecologic tract

Perivascular epithelioid cell tumors (PEComas), rare mesenchymal tumors with myomelanocytic differentiation, can be a diagnostic challenge, often requiring a panel of immunohistochemicalmarkers. Preferentially expressed antigen in melanoma (PRAME) is a relatively new antigen with utility in diagnosing melanomas. This study aimed to survey PRAME expression patterns in the PEComa family of tumors and morphologic mimics. Twenty cases of PEComas and 27 non-PEComas (10 leiomyosarcomas, 3 smooth muscle tumors of uncertain malignant potential [STUMPs], 11 leiomyomas, 1 uterine inflammatory myofibroblastic tumor [IMT], and 2 low-grade endometrial stromal sarcomas [LGESSs]) were stained with PRAME and compared to previously performed HMB45 and Melan-A stains, when available. Tumors showing no or barely perceptible PRAME staining at 10× were considered negative. Tumors were considered positive if there was full nuclear staining evident at 10× in at least one 10× field. Diffuse staining was defined as positivity in at least 80% of tumor nuclei. Overall, PRAME was expressed in 70% of PEComas, with diffuse positivity in 60%. However, PRAME was not specific for PEComas, with immunopositivity in the majority (70%) of uterine leiomyosarcoma cases, though negative in STUMP, leiomyoma, IMT, and LGESS cases. PRAME sensitivity was 70% and specificity was 74%, while HMB45 was more sensitive (90%) and specific (100%), but only 15% of PEComas showed diffuse staining. Melan-A staining was less common than HMB45 or PRAME, with only 18.8% sensitivity but 100% specificity. Among gynecologic PEComas, PRAME was expressed in 75% overall and enriched among malignant cases (85.7% positive). As part of an immunohistochemical panel, PRAME could be useful in the workup of PEComa cases. In the future, PRAME-specific immunotherapies may be beneficial in treating patients with malignant PEComas.

ASSESSMENT OF PROLIFERATIVE ACTIVITY OF ENDOMETRIAL STROMAL TUMORS USING AgNOR TECHNOLOGY

Endometrial stromal sarcomas (ESS) are rare neoplasms that arise from the endometrial stroma and account for less than 1% of all uterine malignancies. Diagnosis of ESS can be challenging due to its morphological overlap with other endometrial tumors, such as endometrial stromal nodules and stromal endometriosis. AgNOR count is a marker of cell proliferation and has been proposed as a potential tool for differentiating between different types of endometrial tumors.In this study, we analyzed the AgNOR count in 50 cases of endometrial tumors, including endometrial stromal nodules, stromal endometriosis, low-grade ESS, and high-grade ESS. Our results show that there is a significant difference in the AgNOR count across different types of endometrial tumors, with the mean AgNOR count increasing with the severity of the tumor. Endometrial stromal nodules had the lowest mean AgNOR count, while high-grade ESS had the highest.These findings suggest that AgNOR count may be a useful marker for differentiating between different types of endometrial tumors, including ESS. However, further research will be needed to confirm these findings and explore the clinical utility of this marker in the diagnosis and management of these conditions. Overall, our study contributes to our understanding of the biology of endometrial tumors and provides valuable information that may be useful in the development of diagnostic and treatment strategies for these conditions.

Endometrial stromal tumor in a young nulliparous women mimicking fibroid uterus – A case report

Endometrial stromal tumor is a rare malignant tumor seen in perimenopausal women. This is a case of endometrial stromal tumour in a young nulliparous woman around her early thirties mimicking Fibroid uterus. She presented with a 34 weeks size mass abdomen with six months duration without any menstrual irregularities. The mass was diagnosed to be a huge sub serous fibroid by both clinical and ultrasonographic examination. MRI revealed a well demarcated, pedunculated mass in the uterine cavity. After the pre operative work up, she was planned for myomectomy where intraoperatively a huge mushroom shaped firm mass was seen arising from the fundus of the uterus with a pedicle which was deep-rooted into the uterus. Histopathological examination of mass confirmed as a Low grade endometrial stromal sarcoma. CT scan was done and revealed no metastatic lesion.

Low-grade endometrial stromal sarcoma: differential with uterine leiomyoma: A rare case report

Endometrial stromal tumors are extremely rare uterine malignancy, mainly among young females. Herein, we report a case of low-grade endometrial stromal tumor in a 19-year-old women who presented with the non-specific symptoms of lower abdominal pain, swelling and vaginal bleeding similar to the uterine leiomyoma. Ultrasound finding showed bulky uterus with multiple fibroid and degenerative changes. Contrast enhanced computed tomography (CECT) displayed diffusely enlarged uterus with heterogenous enhancement of the solid cystic mass with normal bilateral tubes and ovary. Considering the patient in the reproductive age group and her fertility status, she was operated with surgical subtotal hysterectomy. Histopathological examination and immunohistochemistry confirmed the diagnosis of Low-Grade Endometrial Stromal Sarcoma (LG-ESS). Patient was closely followed up for recurrence. Endometrial Stromal Sarcoma (ESS) should be included in the differential diagnosis of uterine leiomyoma to avoid recurrence of the lesion.

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.

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.