Uterine Mesenchymal Tumors: Update on Classification, Staging, and Molecular Features

Uterine perivascular epithelioid cell tumors (PEComa) and the accuracy of proposed classification systems in predicting the malignant versus non-malignant behavior

OBJECTIVE

To compare the accuracy of available classification systems (Folpe, modified Folpe, Bennet, and Schoolmester) in predicting the behavior of uterine Perivascular Epithelioid Cell tumors (PEComas).

METHODS

We reviewed the pathology registry to identify all uterine PEComas treated at our center. We conducted a systematic literature review searching electronic databases from inception to November 2023. We included all references reporting at least one case of uterine PEComa; cases associated with tuberous sclerosis complex were excluded. Patient-level data were extracted by identified records. Survival analysis was used to assess the accuracy of all proposed classification systems to classify uterine PEComas as malignant versus non-malignant.

RESULTS

Six uterine PEComas were treated at our center. The literature search identified 101 uterine PEComas from 32 studies. Eighty-five out of 107 PEComas (28 studies and our series) reported enough follow-up data and details to apply all four classifications. The modified Folpe classification demonstrated the highest hazard ratio (HR) for relapse (HR:8.63; 95% confidence interval [CI] 2.06-36.1) and death due to PEComa (HR:6.8, 95%CI:0.89-51.6) for malignant versus non-malignant PEComas. Changing the cut-off of PEComa size to ≥8 cm and mitotic figures per 50 high power fields to ≥5, the HR for recurrence lowered (HR:6.26; 95% CI 2.20-17.80), but HR for death increased (HR:10.3; 95% CI 1.35-77.80).

CONCLUSIONS

The modified Folpe classification was the most accurate in predicting the PEComa behavior. Changing the cut-off of PEComa size and number of mitotic figures may improve the accuracy in predicting death due to disease.

Uterine Leiomyoma-Like Inflammatory Myofibroblastic Tumor Without Myxoid Matrix or Inflammatory Cell Infiltration: A Case Report of a Potential Diagnostic Pitfall

Inflammatory myofibroblastic tumors (IMTs) of the uterus are relatively rare. Although most IMTs exhibit indolent biological behaviors, local recurrence, and metastasis may occur. Such patients may benefit from targeted therapy; therefore, precise diagnosis is essential for clinical follow up and treatment. Here, we describe a 33-year-old woman with a uterine mass that was detected 4 years previously during pregnancy. The morphology of the tumor resembled that of a uterine leiomyoma, lacking myxoid matrix, and inflammation. Following immunohistochemical and molecular analyses, the tumor was definitively identified as a uterine IMT based on its morphological features. The uterine IMT described in this case had a rare morphology, which can be easily misdiagnosed based on histology alone. Hence, understanding the morphological changes of IMTs in greater detail is imperative to facilitate their accurate diagnosis.

Prognostic factors in uterine adenosarcoma: subanalysis of the SARCUT study

Objective

The purpose of the study was to analyse the role of prognostic factors on the risk of recurrence and overall survival of patients with uterine adenosarcoma.

Methods

A retrospective international multicentre study involving 46 centres collected 32 cases of uterine adenosarcoma, and these cases were included in the present subanalysis. Clinical and demographic features and tumour characteristics were gathered, as well as information on treatment and relapse. Disease-free and overall survival were analysed.

Results

The 5-year disease-free survival (DFS) was 85.3% and the 5-year overall survival (OS) rate was 89.5%. The risk factors significantly associated with overall survival were age (HR 1.09, 95% CI 1.03-1.15; p = 0.004) and FIGO stage II-III (HR 17.75, 95% CI 2.87-109.93; p = 0.002). Patients who experienced early relapse (within 12 months) had a tumour size >30 mm and advanced stage. The majority of recurred cases were treated with radiotherapy or surgery and obtained a good response rate.

Conclusion

The most significant prognostic factors in uterine adenosarcoma were age and FIGO stage and, indirectly, tumour size at diagnosis. The use of secondary surgery and/or radiotherapy could help in prolonging the disease-free status of the patients.

Malakoplakia of the Endometrium: A Rare Unexpected Disease Raising Clinical Concern for Malignancy

Malakoplakia is a rare disease that manifests as a histiocytic inflammatory process and most often occurs in the urinary bladder. It is caused by an impaired capacity of histiocytes to kill and digest bacteria. The typical histopathologic findings are sheets of histiocytes with granular eosinophilic cytoplasm and characteristic Michaelis-Gutmann bodies, spherical bodies with a targetoid appearance. Malakoplakia is even rarer in the gynecologic tract, and our literature search found only 21 published patients of malakoplakia involving the endometrium. Here we report a 60-year-old female patient who presented with recurrent pelvic infections and postmenopausal bleeding, which raised concern for an endometrial malignancy. Hysterectomy with salpingo-oophorectomy revealed malakoplakia involving the endometrium and also the right ovary. Michaelis-Gutmann bodies were visible on the intraoperative frozen section that was performed to rule out an endometrial malignancy. We summarize the clinicopathologic findings of the published patients of endometrial malakoplakia.

Machine Learning Applied to Pre-Operative Computed-Tomography-Based Radiomic Features Can Accurately Differentiate Uterine Leiomyoma from Leiomyosarcoma: A Pilot Study

BACKGROUND

The accurate discrimination of uterine leiomyosarcomas and leiomyomas in a pre-operative setting remains a current challenge. To date, the diagnosis is made by a pathologist on the excised tumor. The aim of this study was to develop a machine learning algorithm using radiomic data extracted from contrast-enhanced computed tomography (CECT) images that could accurately distinguish leiomyosarcomas from leiomyomas.

METHODS

Pre-operative CECT images from patients submitted to surgery with a histological diagnosis of leiomyoma or leiomyosarcoma were used for the region of interest identification and radiomic feature extraction. Feature extraction was conducted using the PyRadiomics library, and three feature selection methods combined with the general linear model (GLM), random forest (RF), and support vector machine (SVM) classifiers were built, trained, and tested for the binary classification task (malignant vs. benign). In parallel, radiologists assessed the diagnosis with or without clinical data.

RESULTS

A total of 30 patients with leiomyosarcoma (mean age 59 years) and 35 patients with leiomyoma (mean age 48 years) were included in the study, comprising 30 and 51 lesions, respectively. Out of nine machine learning models, the three feature selection methods combined with the GLM and RF classifiers showed good performances, with predicted area under the curve (AUC), sensitivity, and specificity ranging from 0.78 to 0.97, from 0.78 to 1.00, and from 0.67 to 0.93, respectively, when compared to the results obtained from experienced radiologists when blinded to the clinical profile (AUC = 0.73 95%CI = 0.62-0.84), as well as when the clinical data were consulted (AUC = 0.75 95%CI = 0.65-0.85).

CONCLUSIONS

CECT images integrated with radiomics have great potential in differentiating uterine leiomyomas from leiomyosarcomas. Such a tool can be used to mitigate the risks of eventual surgical spread in the case of leiomyosarcoma and allow for safer fertility-sparing treatment in patients with benign uterine lesions.

Gynecological sarcomas, surgical management: primary, metastatic, and recurrent disease

Adult-type gynecological soft tissue and visceral sarcomas are rare tumors, with an estimated incidence of 13% of all sarcomas and 4% of all gynecological malignancies. They most often develop in the uterus (83%), followed by the ovaries (8%), vulva and vagina (5%), and other gynecological organs (2%). The objective of this review is to provide an overview of the current management of gynecological sarcomas, according to international guidelines. The management of gynecological sarcomas should follow the recommendations for the management of soft tissue and visceral sarcomas. Centralizing cases in expert centers improves patient survival, both for the diagnostic phase and for multidisciplinary therapeutic management. In the case of pelvic soft tissue sarcomas, a radiological biopsy is essential before any surgical decision is taken. In the case of a myometrial tumour which may correspond to a sarcoma, if conservative surgery such as myomectomy or morcellation is planned, an ultrasound-guided biopsy with pathological analysis including comparative genomic hybridization analysis must be carried out. In all cases, en bloc surgery, without rupture, is mandatory. Many rare histological subtypes require specific surgical management.

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

AIMS

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 to distinguish NTRK-rearranged sarcoma from its mimics.

METHODS AND RESULTS

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 was negative. 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.

CONCLUSION

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.

Aggressive High-grade Uterine Sarcoma Harboring MEIS1-NCOA2 Fusion and Amplification of Multiple 12q13-15 Genes: A Case Report With Morphologic, Immunohistochemical, and Molecular Analysis

MEIS1-NCOA1/2 fusions are recently described gene rearrangements found in rare sarcomas, mainly involving the genitourinary and gynecologic tracts, with 3 cases reported in the uterine corpus. Although local recurrence was very common, no death has been reported, and some investigators consider these sarcomas low grade. Amplification of genes located at the 12q13-15 locus, especially MDM2 , is the hallmark genetic abnormality in well-differentiated and dedifferentiated liposarcoma of the soft tissue. Some uterine tumors have also been reported to harbor MDM2 amplification, including a proportion of Müllerian adenosarcomas, BCOR fusion-positive high-grade endometrial stromal sarcoma, BCORL1 -altered high-grade endometrial stromal sarcoma, rare JAZF1 fusion-positive low-grade endometrial stromal sarcoma, rare undifferentiated uterine sarcoma, and a single case of MEIS1-NCOA2 fusion sarcoma. Here, we report a case of high-grade MEIS1-NCOA2 fusion uterine sarcoma which also harbored amplification of multiple 12q13-15 genes, including MDM2 , CDK4 , MDM4 , and FRS2 , that exhibited aggressive clinical course leading to patient's death within 2 yr of the initial diagnosis. To the best of our knowledge, this is the first documented case of fatal MEIS1-NCOA2 fusion uterine sarcoma, and the second case of MEIS1-NCOA2 fusion uterine sarcoma that also harbors MDM2 amplification.

Fertility-preserving management of an inflammatory myofibroblastic tumor: A case report and review of the literature

Molecular diagnostics have broadened the categorization of mesenchymal tumors of the uterus. Knowledge of the increasing heterogeneity of uterine neoplasms is paramount for the gynecologist as the management and prognosis of these neoplasms differ from those of typical leiomyomas. In this case, a 26-year-old nulligravid patient underwent hysteroscopic management for an enlarging submucosal neoplasm of the uterus. She was found to have an inflammatory myofibroblastic tumor (IMT) after ALK (anaplastic lymphoma kinase) immunostaining. Upon review of pathologic characteristics, she was treated expectantly with repeat hysteroscopy 12 months later. Ongoing conservative management will entail serial pelvic imaging. IMTs should be considered in the differential diagnosis of fibroids presenting in young women. Fertility-preserving management in select patients is appropriate after patient counselling.

High-Sensitivity Mutation Analysis of Cell-Free DNA for Disease Monitoring in Endometrial Cancer

PURPOSE

We sought to determine whether sequencing analysis of circulating cell-free DNA (cfDNA) in patients with prospectively accrued endometrial cancer captures the mutational repertoire of the primary lesion and allows for disease monitoring.

EXPERIMENTAL DESIGN

Peripheral blood was prospectively collected from 44 newly diagnosed patients with endometrial cancer over a 24-month period (i.e., baseline, postsurgery, every 6 months after). DNA from the primary endometrial cancers was subjected to targeted next-generation sequencing (NGS) of 468 cancer-related genes, and cfDNA to a high-depth NGS assay of 129 genes with molecular barcoding. Sequencing data were analyzed using validated bioinformatics methods.

RESULTS

cfDNA levels correlated with surgical stage in endometrial cancers, with higher levels of cfDNA being present in advanced-stage disease. Mutations in cfDNA at baseline were detected preoperatively in 8 of 36 (22%) patients with sequencing data, all of whom were diagnosed with advanced-stage disease, high tumor volume, and/or aggressive histologic type. Of the 38 somatic mutations identified in the primary tumors also present in the cfDNA assay, 35 (92%) and 38 (100%) were detected at baseline and follow-up, respectively. In 6 patients with recurrent disease, changes in circulating tumor DNA (ctDNA) fraction/variant allele fractions in cfDNA during follow-up closely mirrored disease progression and therapy response, with a lead time over clinically detected recurrence in two cases. The presence of ctDNA at baseline (P < 0.001) or postsurgery (P = 0.014) was significantly associated with reduced progression-free survival.

CONCLUSIONS

cfDNA sequencing analysis in patients with endometrial cancer at diagnosis has prognostic value, and serial postsurgery cfDNA analysis enables disease and treatment response monitoring. See related commentary by Grant et al., p. 305.

Uterine inflammatory myofibroblastic tumor presented as abnormal uterine bleeding: Two cases report and literature review

RATIONALE

Inflammatory myofibroblastic tumor (IMT) is an extremely rare soft tissue neoplasm consisting of the proliferation of fibroblastic-myofibroblastic cells with inflammatory infiltrates. It is known to occur in many parts of the body and can generally present with benign or locally recurrent behavior. Anaplastic lymphoma kinase is a specific diagnostic marker for IMT, and approximately 50% of IMT patients have anaplastic lymphoma kinase gene rearrangements. Reports of the female genital tract are rare.

PATIENT CONCERNS

Two patients (a 32-year-old multigravida and a 22-year-old nullipara) visited our clinic because of abnormal uterine bleeding and a uterine mass.

DIAGNOSES

Histopathological examination, immunohistochemical markers, and fluorescence in situ hybridization confirmed the presence of a rare uterine IMT.

INTERVENTIONS

The masses were completely resected via hysteroscopy. The multigravida recurred rapidly in terms of symptoms and images, whereas the nullipara was complaint-free during the follow-up period. Finally, the multigravida underwent hysterectomy and bilateral salpingectomies.

OUTCOMES AND LESSONS

Uterine IMTs can be easily overlooked because of their extremely low incidence rate and insufficient awareness among clinicians; however, uterine IMTs need to be considered in the differential diagnosis of uterine masses. Possible differences in the biological behavior of IMT may exist in different individuals.

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.

Epigenetic Features in Uterine Leiomyosarcoma and Endometrial Stromal Sarcomas: An Overview of the Literature

There is a consensus that epigenetic alterations play a key role in cancer initiation and its biology. Studies evaluating the modification in the DNA methylation and chromatin remodeling patterns, as well as gene regulation profile by non-coding RNAs (ncRNAs) have led to the development of novel therapeutic approaches to treat several tumor types. Indeed, despite clinical and translational challenges, combinatorial therapies employing agents targeting epigenetic modifications with conventional approaches have shown encouraging results. However, for rare neoplasia such as uterine leiomyosarcomas (LMS) and endometrial stromal sarcomas (ESS), treatment options are still limited. LMS has high chromosomal instability and molecular derangements, while ESS can present a specific gene fusion signature. Although they are the most frequent types of "pure" uterine sarcomas, these tumors are difficult to diagnose, have high rates of recurrence, and frequently develop resistance to current treatment options. The challenges involving the management of these tumors arise from the fact that the molecular mechanisms governing their progression have not been entirely elucidated. Hence, to fill this gap and highlight the importance of ongoing and future studies, we have cross-referenced the literature on uterine LMS and ESS and compiled the most relevant epigenetic studies, published between 2009 and 2022.

Sclerosing Perivascular Epithelioid Cell Tumor of the Uterus: A Rare Entity Posing Diagnostic Challenge

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal uterine tumor and the histological variant, sclerosing PEComa is exceedingly rare. Sclerosing PEComas preferentially occur in the retroperitoneum and occurrence in the uterine corpus is seldom seen. These tumors pose a diagnostic challenge and need distinction from morphological mimickers such as epithelioid smooth muscle tumors, endometrial stromal sarcoma, and metastatic carcinoma. Accurate diagnosis can be established coupling histomorphology with immunostaining. The distinction from other entities is of prime importance considering the therapeutic and prognostic implications. Herein, we describe a case of uterine sclerosing variant of PEComa with diagnostic difficulties and key to diagnose this entity.

[Practical diagnostic aspects of uterine leiomyosarcoma in the context of the 2020 WHO classification]

The 2020 WHO Classification defines the spindle cell, epithelioid, and myxoid variants as subtypes of uterine leiomyosarcomas (LMS). Presence of cellular atypia (size variation of polymorphic nuclei > 2-3:1), tumor cell necroses, and mitotic count (usually ≥ 10 MF/10 HPF) are still the key features for diagnostic separation from uterine leiomyomas. Preanalytic variables, staining quality, as well as intralesional geographic distribution may affect the mitotic count. Smooth muscle tumors of uncertain malignant potential (STUMP) still exist as a not yet well-characterized diagnostic entity. Immunohistochemical stains against p16, p53, Ki-67, and WT‑1 may aid differential diagnosis in selected cases. Diagnostic molecular pathology is not yet relevant for diagnosis.

Uterine Sarcomas: How to Navigate an Ever-Growing List of Subtypes

Uterine sarcomas are rare mesenchymal tumors that are aggressive cancers. The rarity of these tumors, and consequently limited prospective data, has made surgical management of uterine sarcomas challenging. One major obstacle in the management of uterine sarcomas is establishing the diagnosis prior to surgery, which is crucial for appropriate intraoperative management. This paper serves to review aspects of surgical management of uterine sarcomas that remain unanswered. Distinguishing common benign myomas from rare uterine sarcomas is important for operative planning and subspecialty care because benign myomas are frequently managed with minimally invasive hysterectomy or myomectomy, whereas the mainstay of management of uterine sarcomas is hysterectomy without specimen fragmentation. Preoperative clinical presentation, serum studies, imaging, and histologic examination all have limitations in establishing a preoperative diagnosis. In addition, patients are often of reproductive age and desire fertility preservation. Although surgery remains the cornerstone for management, high-quality data guiding best practices are sparse. Morcellation should be avoided. Expert pathologic review, imaging to assess for metastatic disease, and consideration of hormone receptor testing are advisable. Recent data have further informed surgical approach and fertility preservation in early-stage disease, but controversy remains. Despite substantial advancement in the medical management of uterine sarcomas, surgical management of uterine sarcomas remain challenging. Larger studies with long-term follow-up are needed to guide fertility preservation surgery options, both local resection and ovarian preservation, further in young women. Development of novel methods to differentiate between benign and malignant uterine masses is needed.

TFE3-associated perivascular epithelioid cell tumor with complete response to mTOR inhibitor therapy: report of first case and literature review

BACKGROUND

Perivascular epitheloid cell tumor (PEComas) are characterized by expression of both muscles, most often smooth muscle actin (in ~80% of cases) and melanocytic markers (mainly HMB-45 and Melan A). TFE 3-associated PEComas are new variant which are poorly defined due to their limited reports in literature. These tumors lack response to targeted mTOR inhibitor therapy due to lack of mutation in TSC gene. Hereby, we are reporting a case of TFE3 associated pelvic PEComa showing excellent response to Everolimus.

CASE PRESENTATION

A 45-year-old female presented with complaint of abdominal mass and bleeding per vaginum for 4 months. She had a history of total abdominal hysterectomy 3 years back in view of abnormal uterine bleeding and exploratory laprotomy 7 months back to remove some pelvic mass. Imaging suggested of ill-defined heterogenous mass of 9.3 x 9.2 x 16 cm involving the uterus, cervix, and upper 1/3 vagina. Multiple omental and peritoneal deposits were also seen, making probable diagnosis of carcinoma endometrium. USG guided biopsy showed cores of fibrous tissue with the presence of cells in sheets with granular eosinophillic cytoplasm; IHC showed positivity for TFE-3, H Caldesmon, GATA-3, and Melan A- and HMB-45; and Ki 67 index was 35%. The basis of above diagnosis of PEComa was made and she was started on Everolimus; repeat imaging after 3 months of therapy showed complete response.

CONCLUSION

We are reporting first case of malignant pelvic TFE 3 PEComa showing response to mTOR therapy. Identification of TFE 3 PEComa is important because they showed different biologic behavior then their conventional PEComa.

New Insights into Hormonal Therapies in Uterine Sarcomas

Simple Summary

Uterine sarcomas are rare mesenchymal malignant cancers, and surgery represents the mainstay of treatment for early-stage disease. In metastatic setting, uterine sarcomas’ treatment includes palliative surgery, a metastases resection, chemotherapy and targeted therapy. Hormonal therapies may also represent an effective option. Frequently, ER and PR are highly expressed in uterine sarcomas patients and they represent a favourable prognostic factor associated with improved overall survival. The scope of the present review is to report the existing evidence and future perspectives on hormonal therapy in uterine sarcomas, with a special focus on aromatase inhibitors, progestins and gonadotropin-releasing hormone analogues, in order to clarify their potential role in daily clinical practice.

Abstract

Uterine sarcoma (US) is a rare mesenchymal malignant cancer type, accounting for 3–7% of uterine malignancies. US prognosis is still poor due to high local and distant recurrence rates. As for molecular features, US may present variable oestrogen receptor (ER) and progesterone receptor (PR) expressions, mostly depending on histotype and grading. Surgery represents the mainstay of treatment for early-stage disease, while the role of adjuvant chemotherapy or local radiotherapy is still debated and defined on the basis of histotype, tumour grading and stage. In metastatic setting, uterine sarcomas’ treatment includes palliative surgery, a metastases resection, chemotherapy, hormonal therapy and targeted therapy. As for the chemotherapy regimen used, drugs that are considered most effective are doxorubicin (combined with ifosfamide or alone), gemcitabine combined with docetaxel and, more recently, trabectedin or pazopanib. Hormonal therapies, including aromatase inhibitors (AIs), progestins and gonadotropin-releasing hormone analogues (GnRH-a) may also represent an effective option, in particular for low-grade endometrial stromal sarcoma (LGESS), due to their favourable toxicity profile and patients’ compliance, while their role is still under investigation in uterine leiomyosarcoma (uLMS), high-grade endometrial stromal sarcoma (HGESS), undifferentiated uterine sarcoma (USS) and other rarer US. The present review aims to analyse the existing evidence and future perspectives on hormonal therapies in US, in order to clarify their potential role in daily clinical practice.

Rhabdomyosarcoma of the uterus in an adult patient with osteopetrosis: a case report

Background

Uterine sarcoma accounts for 3–7% of uterine malignant neoplasms. It is more aggressive than epithelial neoplasms, and patients have a poor prognosis. Rhabdomyosarcoma is classified as a heterologous uterine sarcoma. It is the most common soft tissue malignancy in children while rare in adults. In young patients, the majority of genital tract rhabdomyosarcomas occur in vagina; however, the most common site of gynecologic rhabdomyosarcoma is cervix followed by uterine corpus, in adults. Uterine corpus rhabdomyosarcoma is rare in adults. Diagnosis of pure rhabdomyosarcoma in uterus involves widespread and perfect sampling as well as precise histopathological evaluation to uncover any epithelial component.

Case presentation

Here we report a case of pure rhabdomyosarcoma of uterine corpus in a 60-year-old Iranian postmenopausal female who had osteopetrosis, presenting with 8-month heavy vaginal bleeding and a protruding cervical mass. She is alive on 18-month follow-up after treatment.

Conclusions

Rhabdomyosarcoma of uterine corpus is rare in adults. Diagnosis of pure rhabdomyosarcoma in uterus involves widespread and perfect sampling as well as precise histopathological evaluation to uncover any epithelial component. Treatment options in adult gynecological rhabdomyosarcoma are based on studies in younger patients, and more studies may help us choose the best approach for improving outcome.

SATB2 Expression in Uterine Sarcoma: A Multicenter Retrospective Study

Uterine sarcomas represent a clinical challenge because of their difficult diagnosis and the poor prognosis of certain subtypes. The aim of this study was to evaluate the expression of the special AT-rich sequence-binding protein 2 (SATB2) in endometrial stromal sarcoma (ESS) and other types of uterine sarcoma by immunohistochemistry. We studied the expression of SATB2 on 71 full tissue sections of endometrial stromal nodule, low-grade ESS, uterine leiomyomas and leiomyosarcoma, undifferentiated uterine sarcoma, adenosarcoma, and carcinosarcoma samples. Nuclear SATB2 expression was then evaluated in an extended sample set using a tissue microarray, including 78 additional uterine tumor samples. Overall, with a cut-off of ≥10% of tumor cell staining as positive, the nuclear SATB2 score was negative in all endometrial stromal nodule samples (n=10) and positive in 83% of low-grade ESS samples (n=29/35), 40% of undifferentiated uterine sarcoma (n=4/10), 13% of leiomyosarcoma (n=2/16), 14% of adenosarcoma (n=3/22), and 8% carcinosarcoma (n=2/25) samples. Furthermore, in ESS patients, direct comparison of nuclear SATB2 scores with clinicopathologic parameters and other reported biomarkers such as progesterone receptor and estrogen receptor showed that nuclear SATB2 was associated with PR expression and a decreased risk of disease-specific death (odds ratio=0.06, 95% confidence interval=0.04-0.81, P=0.04). Our data suggest that SATB2 could be a marker with relative sensitivity (83%) for distinguishing between endometrial stromal nodule and ESS with potential prognostic value.

New imaging modalities to distinguish rare uterine mesenchymal cancers from benign uterine lesions

PURPOSE OF REVIEW

Uterine sarcomas are rare and are often challenging to differentiate on imaging from benign mimics, such as leiomyoma. As functional MRI techniques have improved and new adjuncts, such as machine learning and texture analysis, are now being investigated, it is helpful to be aware of the current literature on imaging features that may sometimes allow for preoperative distinction.

RECENT FINDINGS

MRI, with both conventional and functional imaging, is the modality of choice for evaluating uterine mesenchymal tumors, especially in differentiating uterine leiomyosarcoma from leiomyoma through validated diagnostic algorithms. MRI is sometimes helpful in differentiating high-grade stromal sarcoma from low-grade stromal sarcoma or differentiating endometrial stromal sarcoma from endometrial carcinoma. However, imaging remains nonspecific for evaluating rarer neoplasms, such as uterine tumor resembling ovarian sex cord tumor or perivascular epithelioid cell tumor, primarily because of the small number and power of relevant studies.

SUMMARY

Through advances in MRI techniques and novel investigational imaging adjuncts, such as machine learning and texture analysis, imaging differentiation of malignant from benign uterine mesenchymal tumors has improved and could help reduce morbidity relating to misdiagnosis or diagnostic delays.

NCCN Guidelines® Insights: Uterine Neoplasms, Version 3.2021

The NCCN Guidelines for Uterine Neoplasms provide recommendations for diagnostic workup, clinical staging, and treatment options for patients with endometrial cancer or uterine sarcoma. These NCCN Guidelines Insights focus on the recent addition of molecular profiling information to aid in accurate diagnosis, classification, and treatment of uterine sarcomas.

Targeted RNA expression profiling identifies high-grade endometrial stromal sarcoma as a clinically relevant molecular subtype of uterine sarcoma

High-grade endometrial stromal sarcoma (HGESS) may harbor YWHAE-NUTM2A/B fusion, ZC3H7B-BCOR fusion, and BCOR internal tandem duplication (ITD). NTRK3 upregulation and pan-Trk expression were reported in soft tissue lesions that share similar morphology and genetic abnormalities. To confirm these findings in HGESS, differential expression analysis was performed at gene level comparing 11 HGESS with 48 other uterine sarcomas, including 9 low-grade endometrial stromal sarcomas, 23 undifferentiated uterine sarcomas, and 16 leiomyosarcomas, using targeted RNA sequencing data. Pan-Trk immunohistochemistry was performed on 35 HGESS, including 10 tumors with RNA expression data, with genotypes previously confirmed by targeted RNA sequencing, fluorescence in situ hybridization, and/or genomic PCR. Unsupervised hierarchical clustering of the top 25% of differentially expressed probes identified three molecular groups: (1) high NTRK3, FGFR3, RET, BCOR, GLI1, and PTCH1 and low ESR1 expression; (2) low NTRK3, FGFR3, RET, BCOR, GLI1, and PTCH1 and high ESR1 expression; and (3) low NTRK3, FGFR3, RET, BCOR, GLI1, PTCH1, and ESR1 expression. Among HGESS, 64% of tumors clustered in group 1, while 27% clustered in group 2. Cytoplasmic and/or nuclear pan-Trk staining of variable extent and intensity was seen in 91% of HGESS regardless of cyclin D1 and/or BCOR positivity. ER and PR expression was seen in 44% of HGESS despite ESR1 downregulation. Two patients with ER and PR positive but ESR1 downregulated stage I HGESS were treated with endocrine therapy, and both recurred at 12 and 36 months after primary resection. By RNA expression, HGESS appear homogenous and distinct from other uterine sarcomas by activation of kinases, including NTRK3, and sonic hedgehog pathway genes along with downregulation of ESR1. Most HGESS demonstrate pan-Trk staining which may serve as a diagnostic biomarker. ESR1 downregulation is seen in some HGESS that express ER and PR which raises implications in the utility of endocrine therapy in these patients.

Uterine angiomyolipoma: a clinical analysis of 8 cases and literature review

PURPOSE

Uterine angiomyolipoma (AML) is a rare condition involving benign tumors composed of varying proportions of blood vessels, fat, and epithelioid or spindled smooth muscle cells. We analyzed the clinicopathological features, diagnosis and treatment methods, and prognosis of uterine AML.

METHODS

We retrospectively analyzed the clinical-pathological data of eight patients with pathologically diagnosed uterine AML at a single center from January 2008 to July 2020.

RESULTS

The mean age of the patients was 50 years (range, 41-62). One patient was asymptomatic; the main clinical manifestations of the others included vaginal bleeding (3), menorrhagia (2), abdominal pain (1), and dysmenorrhea with adenomyosis (1). In one case, fat components observed via abdominal computed tomography led to a diagnosis of uterine leiomyolipoma; the rest were diagnosed as uterine leiomyoma (4), uterine fibroid degeneration (2), and pelvic mass (1). The lesions were in the body of the uterus (6), the fundus of the uterus (1), and the broad ligament (1). Seven patients had a focal soft tumor texture, and one had a tough texture; the lesions were yellow (3), yellow-white (3), and pinkish white (2). Surgeries included transabdominal myomectomy (2), transabdominal hysterectomy (2), transabdominal hysterectomy/bilateral salpingo-oophorectomy (2), and laparoscopic total hysterectomy/bilateral salpingectomy (2). The median follow-up time was 72 months. No relapses were reported.

CONCLUSION

Uterine AML has a low incidence rate and is most likely to occur in perimenopausal women. The clinical manifestations are similar to those of uterine leiomyomas, but AML should be suspected if the internal echo of the uterine tumor is uneven and contains adipose tissue.

High-grade endometrial stromal sarcoma versus undifferentiated uterine sarcoma: a Turkish uterine sarcoma group study-001

OBJECTIVE

Prognostic factors associated with high-grade endometrial stromal sarcoma (HGESS) and undifferentiated uterine sarcoma (UUS) have not been distinctly determined due to the repetitive changes in the World Health Organization (WHO) classification. We aimed to compare clinicopathologic features and outcomes of patients with HGESS with those of patients with UUS.

METHODS

A multi-institutional, retrospective, cohort study was conducted including 71 patients, who underwent surgery at 13 centers from 2008 to 2017. An experienced gynecopathologist from each institution re-evaluated the slides of their own cases according to the WHO₂₀₁₄ classification. Factors associated with refractory/progressive disease, recurrence or death were examined using logistic regression analyses. Kaplan-Meier method and log-rank test were used for survival comparisons.

RESULTS

The median disease-free survival (DFS) for HGESS and UUS was 12 months and 6 months, respectively. While the median overall survival was not reached in HGESS group, it was 22 months in the UUS group. Kaplan-Meier analyses revealed that patients with UUS had a significantly poorer DFS than those with HGESS (p = 0.016), although OS did not differ between the groups (p = 0.135). Lymphovascular-space involvement (LVSI) was the sole significant factor associated with progression, recurrence or death for HGESS (Hazard ratio: 9.353, 95% confidence interval: 2.539-34.457, p = 0.001), whereas no significant independent factor was found for UUS.

CONCLUSIONS

UUS has a more aggressive behavior than HGESS. While no significant predictor of prognosis was found for UUS, LVSI is the sole independent prognostic factor for HGESS, with patients 9.3 times more likely to experience refractory/progressive disease, recurrence or death.

Biomaterial strategies to replicate gynecological tissue

Properties of native tissue can inspire biomimetic in vitro models of gynecological disease.

Survival outcomes and prognostic factors of endometrial stromal sarcoma and undifferentiated uterine sarcoma

PURPOSE

To review the diagnostic and therapeutic procedures of patients diagnosed with Endometrial Stromal Sarcoma (ESS) and Undifferentiated Uterine Sarcoma (USS) at our institution and investigate their clinical outcomes and factors affecting prognosis.

METHODS

We retrospectively collected demographic data, preoperative diagnostic methods and therapeutic management of patients treated for ESS and UUS between January 1995 and December 2019 at Vall d'Hebron Barcelona Hospital Campus, Spain. Overall survival and disease-free survival were calculated. Cox proportional-hazards regression models were calculated.

RESULTS

Sixty-three patients were included in the study, of which 51(81%) had a diagnosis of ESS and 12(19%) of UUS. Twenty patients (31.7%) were diagnosed after a previous non-oncologic surgery, and 12 of them (60%) suffered from tumor disruption. Cytoreductive procedures were needed in 29 patients (46%), and optimal cytoreduction was achieved in 80.9% of the patients. The median follow-up was 7.6 years (IQR = 0.99-14.31). Five-year overall survival was 57.6% (44.2-68.8) and was significantly better for low-grade ESS (LG-ESS) patients (p < 0.01). Five-year disease-free survival was 57.1% (42.8-69.1) and was also significantly higher in LG-ESS cohort (p = 0.03). After multivariate analysis histological type, age, FIGO stage, optimal surgery and mitotic index were found significantly correlated with survival. For high-grade EES (HG-ESS) and USS patients adjuvant radiotherapy also correlated with improved survival.

CONCLUSION

Overall survival and disease-free survival are significantly better in patients with LG-ESS cohort. HG-ESS and UUS show similar survival outcomes. Age, FIGO stage, optimal surgery and histological type were significantly correlated with survival in the global cohort, whilst adjuvant radiotherapy correlated with improved survival in HG-ESS and UUS patients.

Italian consensus conference on management of uterine sarcomas on behalf of S.I.G.O. (Societa' italiana di Ginecologia E Ostetricia)

BACKGROUND

Uterine sarcomas are very rare tumours with different histotypes, molecular features and clinical outcomes; therefore, it is difficult to carry out prospective clinical trials, and this often results in heterogeneous management of patients in the clinical practice.

AIM

We planned to set up an Italian consensus conference on these diseases in order to provide recommendations on treatments and quality of care in our country.

RESULTS

Early-stage uterine sarcomas are managed by hysterectomy + bilateral salpingo-oophorectomy according to menopausal status and histology; lymphadenectomy is not indicated in patients without bulky nodes, and morcellation must be avoided. The postoperative management is represented by observation, even though chemotherapy can be considered in some high-risk patients. In early-stage low-grade endometrial stromal sarcoma and adenosarcomas without sarcomatous overgrowth, hormonal adjuvant treatment can be offered based on hormone receptor expression. In selected cases, external beam radiotherapy ± brachytherapy can be considered to increase local control only. Patients with advanced disease involving the abdomen can be offered primary chemotherapy (or hormonal therapy in the case of low-grade endometrial stromal sarcoma and adenosarcoma without sarcomatous overgrowth), even if potentially resectable in the absence of residual disease in order to test the chemosensitivity (or hormonosensitivity); debulking surgery can be considered in patients with clinical and radiological response. Chemotherapy is based on anthracyclines ± ifosfamide or dacarbazine. Palliative radiotherapy can be offered for symptom control, and stereotactic radiotherapy can be used for up to five isolated metastatic lesions.

CONCLUSIONS

Treatment of uterine sarcoma should be centralised at referral centres and managed in a multidisciplinary setting.

Metastatic low-grade endometrial stromal sarcoma after 24 years: A case report and review of recent molecular genetics

Low-grade endometrial stromal sarcoma (LGESS) is a rare malignant uterine tumor with the potential to metastasize years after the primary resection. There is a broad differential diagnosis for endometrial stromal sarcomas (ESS), including both benign and malignant entities. Herein, we present the case of a 64-year-old female with metastatic LGESS to the lung, diagnosed by cytology, 24 years after her initial presentation. This report discusses the cytomorphologic and histopathologic characteristics, and ancillary studies including immunohistochemical stains and recent advances in molecular diagnostics of ESS. Accurate diagnosis of spindle cell lesions in the lung can be challenging. As such, this case highlights the instrumental role of ancillary testing and molecular diagnostics to achieve a more definitive diagnosis.

Uterine mesenchymal tumours: recent advances

Almost all uterine mesenchymal tumours have been historically classified as either smooth muscle or endometrial stromal neoplasms. Recent application of molecular techniques has identified numerous lesions with distinctive genetic abnormalities and clinicopathological characteristics. Newly discovered uterine sarcoma subtypes include high-grade endometrial stromal sarcomas with BCOR genetic abnormalities, fibrosarcoma-like uterine sarcomas with NTRK rearrangements and COL1A-PDGFRB fusions, as well as undifferentiated uterine sarcomas with SMARCA4 mutations. Novel PLAG1 and PGR fusions have been identified in subsets of myxoid and epithelioid leiomyosarcomas. Some uterine tumours resembling ovarian sex-cord tumour harbour GREB1 and ESR1 rearrangements. Histological and immunophenotypical features as well as underlying genetic abnormalities defining these lesions are discussed.

A novel MBTD1-PHF1 gene fusion in endometrial stromal sarcoma: A case report and literature review

The classification of endometrial stromal sarcoma (ESS) has been refined and aided by the discovery of various recurrent gene translocations. Low-grade ESS (LG-ESS) is most commonly characterized by JAZF1-SUZ12 fusions followed by rearrangements involving PHD finger protein-1 (PHF1) and multiple fusion partners, including JAZF1, EPC1, EPC2, and MEAF6. In the present study, integrating anchored polymerase chain reaction and paired-end next-generation ribonucleic acid sequencing, we identified the presence of a novel malignant brain tumor domain-containing 1 (MBTD1)-PHF1 gene fusion in a case of LG-ESS. MBTD1 belongs to the Polycomb gene group, and its fusion with PHF1 is predicted to mediate tumorigenesis through aberrant transcriptional repression. Histology and immunohistochemical studies demonstrated conventional morphology for LG-ESS and clinical follow-up showed no progression of disease after 6 months. These findings help expand the current knowledge on the spectrum of gene rearrangements in the diagnosis of ESS.

Inflammatory Myofibroblastic Tumors in the Uterus: Childhood-Case Report and Review of the Literature

Inflammatory myofibroblastic tumor (IMT) is a spindle cell neoplasm with low malignant potential, which may appear in different parts of the body. Uterine localization is rare, especially among children. Etiology is unclear, although some authors suggest underlying trauma or distress. A 3.5-year-old girl was treated at our institute for recurring vaginal bleeding without injury or known pathology. Physical examination and laboratory analysis revealed no specific findings, contrast-enhanced MRI found a 25 × 28 × 30 mm-sized inhomogeneous soft tissue mass in the uterus wall, which was excised in toto. Histological examination identified a spindle cell pattern, and the FISH test revealed ALK gene rearrangement, the lesion was defined as an IMT. Six cases were published to date, and their diagnostic methods are not equivocal, CT, and PET CT were preferred instead of MRI. Aggressive therapy seems to be exaggerated according to low recurrence and metastasis occurrence, and crizotinib is proved as good therapeutic agent in those cases. Biopsy and histology has important role in order to distinguish IMT from malignancies completed with FISH examination because ALK positivity strengthens the diagnosis. No lethal outcome was published among children, as our patient is also symptom-free after 3 years.