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.     

子宫内膜间质肉瘤9例临床病理分析

目的 探讨子宫内膜间质肉瘤(endometrial stromal sarcoma,ESS)的临床病理特征、诊断、鉴别诊断及预后.方法 对9例ESS患者进行临床、病理资料分析、免疫组化检测及随访.结果 患者年龄39～64岁,中位46.3岁.临床主要表现为阴道流血及子宫增大/占位.肿瘤直径2.3～11 cm,平均4.6 cm.光镜下8例呈低度恶性子宫内膜间质肉瘤(low grade endometrial stromal sarcoma,LGESS),均由类似增殖期子宫内膜间质肿瘤细胞构成,细胞密集,异型性不明显,呈不规则舌状或岛状浸润肌层,并伴较多薄壁螺旋小血管;1例为高度恶性子宫内膜间质肉瘤/未分化子宫内膜肉瘤(high grade endometrial stromal sarcoma/undifferentiated endometrial sarcoma,HGESS/UES),肿瘤细胞直接替代子宫肌层,具有明显的细胞异型性,无LGESS常见的螺旋小血管.免疫组化检测显示肿瘤细胞CD10、vimentin均阳性,PR、ER大部分阳性,SMA和desmin及h-Caldesmon为极少数局灶阳性,S-100、CD34均阴性.术后随访7例(平均53个月),只有1例HGESS/UES死亡.结论 ESS是女性生殖道很少见的一种恶性肿瘤,恶性度相差很大.确诊主要依靠其临床病理特点,并辅以免疫组化标记综合分析.诊断时要与子宫内膜间质结节、平滑肌肿瘤、低分化癌等鉴别.     

子宫内膜间质肉瘤55例临床病理特点和预后分析

目的 了解子宫内膜间质肉瘤(ESS)的病理形态特征并分析影响预后的相关指标.方法 收集该院55例ESS患者的临床和病理资料,所有病例重新阅片,参照文献分类为低级别子宫内膜间质肉瘤(LGESS)、不伴核多形的未分化子宫内膜肉瘤(UES-U)、伴有核多形的未分化子宫内膜肉瘤(UES-P);同时观察肿瘤细胞的形态特点,包括纤维样、肌样、黏液样、上皮样分化,并计数核分裂象等.对所有病例进行临床资料的收集并随访.结果 LGESS、UES-U、UES-P型病例分别为39、9、7例.病理形态上,ESS有多种形态分化并存的特点,LGESS、UES-U及UES-P型病例中分别有12.8%(5/39)、5/9及5/7伴有两种以上混合的形态学分化;同一病例的不同区域核分裂象计数和组织学类型亦存在较大差异.临床上肿瘤复发比例分别为51.6%(16/31)、5/6、2/3;LGESS无死亡病例,UES-U和UES-P中各有2例死亡,且UES-U的死亡病例均有局灶UES-P区域.按核分裂象最高计数进行预后分析,≥10/10 HPF的病例复发率显著高于＜10/10 HPF的复发率(P=0.009),在LGESS病例中亦存在这种统计学差异,所有死亡病例的核分裂象最高计数均＞30/10 HPF.结论 ESS常见不同程度分化重叠及多向分化的特点,尤以UES-U和UES-P中更为常见,因此应充分取材以寻找诊断线索.肿瘤中伴有UES-P图像,同时伴核分裂象计数高度活跃可能会增加死亡风险.在LGESS病例中,核分裂象最高计数≥10/10 HPF的肿瘤复发率显著增高,在诊断时应引起重视.

Abstract：

Objective To investigate the clinicopathologic features and the prognostic factors of endometrial stromal sarcoma (ESS). Methods 55 cases of endometrial stromal sarcoma were reviewed and categorized into 3 pathologic types based on the related literatures, i.e. , low grade endometrial stromal sarcoma (LGESS), undifferentiated endometrial sarcoma with nuclear uniformity (UES-U) and undifferentiated endometrial sarcoma with nuclear pleomorphism (UES-P). Meanwhile, the pathologic features were reviewed, including fibroid, myoid, mucoid, and epithelioid differentiation and mitotic index.Clinical and follow-up data were collected. Results In endometrial stromal sarcoma, two or three pathologic types co-existed in one case, including 12. 8% (5/39) of LGESS, 5/9 of UES-U, and 5/7 of UES-P.Mitotic index varied in different regions of one tumor from rare to high. Multi-differentiation was also commonly seen in ESS. The numbers of cases in LGESS, UES-U and UES-P were 39, 9 and 7, with recurrence rate of 51.6% ( 16/31 ), 5/6 and 2/3, respectively. There was no death case in LGESS, and 2 cases were died in UES-U and UES-P, respectively. In the 2 death cases of UES-U, both had focus of UES-P. There was a significant difference in the recurrence rate between cases with different mitotic index ( ≥ 10/10 HPF and ＜ 10/10 HPF, P = 0. 009), especially in LGESS group. All death cases had high mitotic index ( ＞ 30/10 HPF). Conclusions It is a common phenomenon in ESS that two or three pathologic types may exist in one case, especially in UES-U and UES-P. And multi-differentiation is also commonly seen in ESS. So adequate pathologic sampling is important for pathologists to make a correct diagnosis of ESS in daily work. The recurrence rates are significantly higher in cases with high mitotic index,especially in LGESS. In addition, the presence of UES-P and high mitotic index may increase the risk of death in the patients.     

Pleomorphic high grade endometrial stromal sarcoma with YWHAE gene amplification may be a novel variant with poor prognosis

Endometrial stromal neoplasms are classified by the World Health Organization (WHO) into endometrial stromal nodule (ESN), low grade (LGESS), high grade (HGESS), and undifferentiated uterine sarcoma (UUS). HGESS is subclassified based on molecular findings, YWHAE or BCOR. The HGESS with YWHAE::NUTM2A/B (alias YWHAE::FAM22A/B) fusion usually have relatively monomorphic (as with most fusion-associated malignancies) rounded to epithelioid cells with eosinophilic cytoplasm, vesicular nuclei, nucleoli, and mitotic figures >10/10 HPF. We present a 66-year-old woman with post-menopausal bleeding found to have a heterogeneous solid-cystic uterine mass on CT who underwent total hysterectomy, bilateral salpingo-oophorectomy, omentectomy, and pelvic lymph node dissection. A 15.0×9.0 cm variegated uterine mass with hemorrhage and necrosis was identified. Histologically, the tumor was hypercellular with haphazard fascicles, microcysts, and tongue-like destructive myometrial invasion. Tumor cells exhibited marked pleomorphism and high mitotic activity with atypical mitotic figures. There was extensive cyclin-D1 and subset CD10 immunopositivity. FISH showed YWHAE amplification but without rearrangement. Interestingly, we found only two other reported cases of pleomorphic HGESS with YWHAE gene amplification upon review of 259 cases from cBioPortal database, one of which was reported as carcinosarcoma with heterologous elements. Of note, all three YWHAE amplified cases were diagnosed at high-stage and succumbed to disease within six months. Our case appears to be the third case of YWHAE-amplified pleomorphic HGESS, possibly a new variant of uterine sarcoma with aggressive biologic behavior that needs further evaluation.     

An endometrial stromal tumor with osteoclast-like giant cells

Endometrial stromal tumors (ESTs) of the uterine corpus have a striking propensity to display diverse morphological variations, including sex cord-like, smooth muscle, or skeletal muscle differentiation; fibrous change; myxoid change; or bland endometrioid-type glands. They may also contain rhabdoid, foam, clear, or epithelioid/granular cells among others. Recently, we have encountered an EST showing smooth muscle differentiation and osteoclast-like giant cells that were predominantly concentrated in the areas showing smooth muscle differentiation. Osteoclastlike giant cells have not been previously reported in EST to our knowledge; thus, this finding expands the morphological spectrum of these tumors. In addition, although the level of infiltration at the peripheries of the tumor exceeded that allowable under the Tavassoli and Norris criteria for stromal nodules, it did not reach the classic permeative infiltration generally associated with endometrial stromal sarcomas. Historical, prognostic, and diagnostic aspects of margins in EST, especially in those borderline cases such as ours, are also discussed.     

Steroid hormone receptors in endometrial stromal sarcomas. A biochemical and immunohistochemical study.

Seven cases of endometrial stromal sarcoma (five low grade and two high grade) were analyzed immunohistochemically for the presence of estrogen and progesterone receptors. In four cases (three low grade and one high grade), these results were compared to biochemical findings. All low-grade endometrial stromal sarcomas were positive for progesterone receptors using immunohistochemical techniques. These results correlated well with biochemical evaluation of progesterone receptors. The high-grade endometrial stromal sarcomas were negative for progesterone and estrogen receptors by both methods. The advantages of immunohistochemical evaluation of steroid receptors have been well established in breast and endometrial carcinomas. This study demonstrates the usefulness of this technique in endometrial stromal sarcomas.     

High grade endometrial stromal sarcoma on thinprep

High grade endometrial stromal sarcoma (HGESS) is an uncommon malignancy recently re‐defined in the new WHO classification of endometrial stromal tumors. In this article, we discuss the differential diagnoses of metastatic HGESS in a fine needle aspiration (FNA) of a lymph node and compare the cytomorphology of HGESS in ThinPrep [(TP), Hologic Inc., Boxborough, MA] to conventional smears (CS). The patient had a history of stage I HGESS, status‐post supracervical hysterectomy without regional lymph node metastases. Her post‐operative course was complicated by pelvic fluid collections and enlarging para‐aortic lymph nodes. Diff‐Quik (DQ)‐stained and Papanicolaou (Pap)‐stained smears from a para‐aortic lymph node FNA demonstrated a cellular specimen with monomorphic population of plump to oval cells with scant, wispy cytoplasm in aggregates and as single cells. The nuclei showed fine chromatin and small inconspicuous nucleoli. Compared to the CS, HGESS cells in the TP showed similar cytological features, with the exception that the nuclei were slightly smaller, hyperchromatic, and the chromatin pattern was attenuated. In the absence of prior clinical history, the cytomorphology of metastatic HGESS in a lymph node can be difficult to differentiate from a lymphoma, a variety of metastatic spindle cell tumors or metastatic carcinoma. Immunohistochemical analysis and comparison with the primary tumor can be useful in proving the nature of the malignant cells. The cytomorphology of HGESS on TP correlated well in both single cells and aggregates when compared to CS. The differences noted were decreased nuclear size, nuclear hyperchromasia, and slightly attenuated nuclear detail on TP. Diagn. Cytopathol. 2015;43:756–762. © 2015 Wiley Periodicals, Inc.     

Distinction of endometrial stromal sarcomas from 'hemangiopericytomatous' tumors using a panel of immunohistochemical stains.

Endometrial stromal sarcomas are low-grade malignant tumors that may pose a diagnostic challenge, especially when they are present in an extrauterine site. Owing to the presence of an arborizing vasculature and cells with an undifferentiated appearance, endometrial stromal sarcomas can be confused with several soft-tissue neoplasms. We studied 17 endometrial stromal sarcomas, eight hemangiopericytomas, 14 solitary fibrous tumors, and 16 synovial sarcomas immunohistochemically, detecting the following antigens: CD10, estrogen receptor, progesterone receptor, bcl-2, CD34, smooth muscle antigen, epithelial membrane antigen and cytokeratin (AE1/AE3). Most endometrial stromal sarcomas stained positively for CD10 (16/17), estrogen receptor (17/17), progesterone receptor (15/17), and bcl-2 (17/17). Staining with antismooth muscle antigen was seen in 11 of 17 cases of endometrial stromal sarcoma, with more intense staining seen in areas showing smooth muscle differentiation. Staining with AE1/3 was seen in four of 17 endometrial stromal sarcomas, with two of the positive cases containing epithelioid cells. None of the endometrial stromal sarcomas expressed epithelial membrane antigen or CD34. More than half of the hemangiopericytomas (4/8) and solitary fibrous tumors (9/14) cases demonstrated CD10 expression either focally or in a patchy cytoplasmic and membranous pattern. Hemangiopericytomas, solitary fibrous tumors, and synovial sarcomas did not express estrogen receptor. Four of eight hemangiopericytomas and seven of 14 solitary fibrous tumors also showed patchy progesterone receptor expression. CD34 expression was identified in six of eight hemangiopericytomas and 13 of 14 solitary fibrous tumors, but we did not find expression of CD34 in synovial sarcoma. Differences between endometrial stromal sarcoma and other soft-tissue tumors were detected for all of the immunohistochemical markers (P<0.05), except anti-bcl-2 and AE1/3. Antibodies against CD10 mark a substantial number of hemangiopericytomas and solitary fibrous tumors (albeit not diffusely) and should always be combined with antiestrogen receptor and CD34 when the differential diagnosis includes endometrial stromal sarcoma. Unlike estrogen receptor antibodies, progesterone receptor antibodies show at least focal nuclear staining in most hemangiopericytomas, solitary fibrous tumors and rare synovial sarcomas, and are not useful for this differential diagnosis. All endometrial stromal sarcomas expressed bcl-2, mostly in a diffuse pattern, but this did not distinguish between endometrial stromal sarcoma and mimics. We therefore recommend the use of a small antibody panel comprising anti-CD10, anti-estrogen receptor, and anti-CD34 to distinguish endometrial stromal sarcomas from tumors with a predominant hemangiopericytomatous growth pattern.     

Computerized image analysis of p53 and proliferating cell nuclear antigen expression in benign, hyperplastic, and malignant endometrium.

CONTEXT: The endometrium is an intrinsically dynamic tissue with great capability for regeneration and proliferation; consequently, there is some overlap between features seen in benign, premalignant, and malignant lesions. This leads to marked intrabiopsy, interbiopsy, and interobserver variability. OBJECTIVE: We studied the specificity and sensitivity of computerized image analysis of molecular markers to evaluate its potential use as a diagnostic tool. DESIGN: Specimens from 100 patients were examined and the following histologic diagnoses were assigned: proliferative endometrium (n = 10), secretory endometrium (n = 10), endometrial hyperplasia (n = 40; 30 with no atypia, 10 with atypia), and carcinoma (n = 40; 20 endometrioid, 10 serous, and 10 clear cell). All cases were evaluated immunohistochemically for p53 and proliferating cell nuclear antigen (PCNA) expression. Computerized image analysis was performed with a CAS 200 digital analyzer. RESULTS: Expression of p53 was found only in carcinomas (65%) and endometrial hyperplasia with atypia (30%). Expression of p53 was higher in the poor prognostic categories (serous carcinoma and clear cell carcinoma) than in endometrioid carcinoma. In endometrioid carcinoma, p53 expression correlated with grade. Proliferating cell nuclear antigen showed a similar pattern of results to p53 in the various carcinoma subtypes and endometrioid carcinoma grades. Endometrial hyperplasia PCNA values were the lowest among all the groups. Both carcinomas and proliferative endometrium showed higher glandular and stromal PCNA values, significantly different from endometrial hyperplasia with atypia. In proliferative endometrium, stromal PCNA was the highest among all of the groups. The p53 and PCNA results correlated with each other for carcinoma. CONCLUSIONS: Computerized image analysis correlates well with the established morphologic groups of endometrial pathology and yields results consistent with previous studies. Owing to its higher degree of sensitivity, computerized image analysis is of potential use in cases of diagnostic dilemmas and can help objectively allocate the case in the correct category (e.g., proliferative endometrium vs. endometrial hyperplasia, endometrial hyperplasia with atypia vs. endometrioid carcinoma). It is particularly useful in the evaluation of stromal changes.     

Prognostic significance of histologic grade and nuclear expression of beta-catenin in synovial sarcoma

Synovial sarcoma, which has a wide spectrum of biologic behavior, warrants accurate grading to assess the patient's prognosis. We studied the clinicopathologic and immunohistochemical features of 44 cases of synovial sarcoma in patients treated primarily or secondarily at the National Cancer Center, Tokyo, to identify independent prognostic factors. There were local recurrences in 16 patients (36%), and 25 (57%) developed metastases, primarily to the lungs. The estimated cumulative 5-year and 10-year survival rates were 68% and 41%, respectively. Variables associated with an adverse outcome included tumor size > 6.7 cm; initial treatment outside the National Cancer Center; poorly differentiated subtype; high nuclear atypia; mitosis count > 27/10 high-power fields; tumor necrosis; absence of stromal calcification; nuclear expression of beta-catenin, which was found in 25 cases (57%); Ki-67 (MIB-1) index > 27%; and histologic grade 3. Nuclear accumulation of beta-catenin as a cell-signaling event may play an important role in the progression of synovial sarcoma and therefore might be predictive of short survival. However, multivariate analysis clearly showed that only histologic grade, as defined by using categorized variables for the MIB-1 index and tumor necrosis, was an independent prognostic factor. Most variables were correlated with lung metastasis and histologic grade. High-grade synovial sarcoma assessed by a histologic grading system based on the proliferative activity of the neoplastic cells can be viewed as high risk with the patients most likely to die of disease within 10 years after surgery and in need of improved chemotherapy. HUM PATHOL 32:257-263.     

Myogenous phenotype of epithelial-like areas in endometrial stromal sarcomas

Approximately 25% of low-grade endometrial stromal sarcomas of the uterus contain areas of epithelial-like differentiation, which are often reminiscent of ovarian sex-cord tumors. It has been suggested that these areas may represent attempted differentiation toward either uterine glands or smooth muscle. To investigate these two possibilities, we examined the histologic and immunohistochemical features of 26 low-grade endometrial stromal sarcomas. Eight tumors had epithelial-like differentiation, which in some tumors was so prominent as to suggest a purely epithelial neoplasm. Areas typical of endometrial stromal sarcoma were vimentin positive, whereas epithelial-like differentiation expressed vimentin and the muscle markers muscle-specific actin and desmin, as well as cytokeratin, but not the epithelial marker epithelial membrane antigen. Epithelial-like differentiation in low-grade endometrial stromal sarcoma is not uncommon and, based on our immunohistochemical results after comparison with normal controls, epithelial-like differentiation has a myogenous rather than an epithelial phenotype.     

Grading of spindle cell sarcomas in fine-needle aspiration biopsy specimens

We studied whether histologic criteria for grading sarcomas could be applied to fine-needle aspiration biopsy (FNAB) specimens of adult spindle cell sarcomas, without knowledge of the sarcoma subtype, by reviewing 36 specimens. Grade 1 was assigned for minimal nuclear atypia and overlap, no necrosis, and rare mitotic figures, and grade 2 for moderate nuclear atypia, at least moderate nuclear overlap, appreciable mitotic figures, and necrosis. Severe nuclear atypia distinguished grade 3 from grade 2. A major noncorrelation between FNAB and histologic grades was defined as a misclassification of grade 1 vs grade 2 or 3. FNAB grades assigned were grade 1, 1; grade 2, 25; and grade 3, 10. There was 1 major noncorrelation due to a probable FNAB interpretation error. In 15 of 16 FNAB specimens of grade 2 or 3 sarcomas lacking mitotic figures, necrosis, or both, the nuclear atypia reflected the grade. In the remaining case, the degree of nuclear overlap and necrosis determined the grade. The histologic grading of sarcomas can be applied accurately to most FNAB specimens of spindle cell sarcomas without knowledge of the sarcoma subtype.     

Endometrial stromal tumors: an update on a group of tumors with a protean phenotype

Endometrial stromal tumors are reviewed with emphasis on their wide morphologic spectrum and problems in differential diagnosis, highlighting issues that have received particular attention in the recent literature. These neoplasms are divided into two major categories--endometrial stromal nodules and endometrial stromal sarcomas--a distinction made on the basis of the lack of significant infiltration at the periphery of the former. The division of endometrial stromal sarcomas into low-grade and high-grade categories has fallen out of favor and the designation endometrial stromal sarcoma is now considered best restricted to neoplasms that were formally referred to as "low-grade" stromal sarcoma. Endometrial sarcomas without recognizable evidence of a definite endometrial stromal phenotype, designated poorly differentiated "endometrial sarcomas," are almost invariably high grade and often resemble the mesenchymal component of a malignant mullerian mixed tumor. Two features of endometrial stromal tumors that may cause confusion are smooth muscle differentiation and epithelial patterns. Cases in the former category often have a characteristic "starburst" pattern of collagen formation. The most common epithelial patterns resemble those seen in ovarian sex-cord stromal tumors. Much less common is endometrioid gland differentiation. Some endometrial stromal tumors have a prominent fibrous or myxoid appearance and the myxoid tumors should be distinguished from myxoid leiomyosarcoma. Other unusual features of endometrial stromal tumors are also discussed. Lesions in the differential diagnosis of uterine endometrial stromal neoplasms include highly cellular leiomyoma, cellular intravenous leiomyomatosis, adenomyosis with sparse glands, metastatic carcinoma, and lymphoma. Endometrial stromal sarcomas at extrauterine sites may be primary or metastatic from a uterine tumor, the latter sometimes being occult and difficult to definitively establish, particularly if there is a history of a remote hysterectomy for "leiomyomas." Endometrial stromal sarcomas of the ovary, whether primary or metastatic, may be difficult to distinguish from ovarian sex-cord stromal tumors. Extragenital endometrial stromal sarcomas may be confused with diverse lesions such as gastrointestinal stromal tumors, hemangiopericytoma, lymphangiomyomatosis, or mesenchymal cystic hamartoma of the lung. Immunohistochemistry may play a role in evaluating these tumors and in some instances establishing the diagnosis although conventional light microscopic analysis suffices in the majority of cases. The unusual tumor, the "uterine tumor resembling an ovarian sex-cord tumor," is also considered in this review as it is almost certainly of endometrial stromal derivation in many cases. These neoplasms may have a striking resemblance to granulosa cell tumors or Sertoli cell tumors, including those with a retiform pattern, and have recently been shown to be frequently inhibin positive.     

Cytogenetic and molecular aberrations in endometrial stromal tumors

Endometrial stromal tumors (ESTs) are rare uterine mesenchymal tumors, comprising <10% of all uterine mesenchymal neoplasms. The latest World Health Organization classification divides endometrial stromal tumors into 3 categories based on morphologic features: endometrial stromal nodule (ESN), low-grade endometrial stromal sarcoma, and undifferentiated endometrial sarcoma. Specific cytogenetic aberrations and molecular genetic alterations have recently been identified in endometrial stromal tumors, providing insights into their molecular biology, potential diagnostic markers, and possible therapeutic targets. Currently, recurrent chromosomal rearrangements resulting in gene fusion play a substantive role in the pathogenesis of endometrial stromal nodules, endometrial stromal sarcomas, and a small subset of undifferentiated endometrial sarcomas. Loss of heterozygosity of tumor suppressor genes and deregulation of the Wnt signaling pathway have also been implicated in EST tumorigenesis. In this review, we summarize the recent advances in the molecular pathology of endometrial stromal tumors.     

Uterine stromal neoplasms: a clinicopathologic and DNA flow cytometric correlation

Twenty-five uterine stromal neoplasms (five stromal nodules and 12 low-grade and eight high-grade stromal sarcomas) were studied to determine the correlation between clinicopathologic features, flow cytometric tumor DNA content and proliferative fraction, and patient outcome. Fifteen of the 20 sarcomas (five of them high grade) were confined to the uterus (stages I and II); the other five (two low grade and three high grade) extended outside the uterus (stages III and IV). Stromal nodules and low-grade sarcomas manifested diploid DNA content and low proliferative index. All stromal nodules and the majority of low-grade sarcomas pursued a benign clinical course. Two cases of low-grade sarcoma ran a malignant course; both patients had high-stage disease. Three of the high-grade sarcomas were diploid and five were aneuploid. All eight neoplasms demonstrated high proliferative index and seven ran a malignant course (four of five were stage I and three of three were stage IV). Three high-grade stage I tumors had a low mitotic rate but a high proliferative index and ran an aggressive course. All high-stage sarcomas were clinically aggressive, irrespective of their histologic classification or DNA characteristics. The proliferative index by flow cytometry may offer an objective adjunct in predicting the aggressive potential of a subset in low-stage neoplasms.     

Uterine tumour resembling an ovarian sex cord tumour

Endometrial stromal sarcomas account for 0.25% of all uterine malignancies. These tumours were originally divided into low grade and high grade stromal sarcomas, but the recent World Health Organisation classification (2003) recognises low grade stromal sarcoma and undifferentiated endometrial sarcoma. Low grade sarcomas may exhibit other forms of differentiation, including smooth muscle and sex cord differentiation. In the latter form, the tumour contains epithelial-like or sex cord-like elements often with epithelioid appearance, arranged in nests, cords, trabeculae, solid, or tubular structures. If this element predominates, the tumour is considered to be a uterine tumour resembling ovarian sex cord tumour, and may cause diagnostic difficulties. This case report describes the histological and immunohistochemical features of a uterine stromal sarcoma showing exclusively a pattern reminiscent of ovarian sex cord tumour.     

Expression of metalloproteinases endometrial stromal sarcoma: immunohistochemical study using image analysis.

AIM: To investigate the expression of matrix metalloproteinases (MMP), a group of proteolytic enzymes with a central role in extracellular matrix invasion and degradation, in stromal sarcomas. METHODS: 11 endometrial stromal sarcomas (four low grade tumours, seven high grade) were stained for MMP-2, MMP-3, and MMP-9 using immunohistochemical stains. The surgical material consisted of nine hysterectomy specimens and two pelvic recurrences. Three hysterectomy specimens, removed for leiomyomas, were studied as controls. Staining area was evaluated using image analysis. RESULTS: Age at the time of diagnosis ranged from 21 to 67 years. Four of the 11 patients (three with high grade tumours and one with a low grade tumour) died of the disease, six remained free of disease, and one was lost to follow up. Staining for MMP-2, MMP-3, and MMP-9 was more diffuse in high grade tumours than in low grade tumours and controls. Staining for MMP-3 and MMP-9 was more pronounced in high grade than in low grade tumours (p = 0.04; p = 0.05). Staining for MMP-9 was significantly greater in all stromal sarcomas than in controls (p < 0.001 for high grade tumours v controls; p < 0.01 for low grade tumours v controls). Diffuse staining for MMP-2, exceeding 90% of the tumour area, was observed in three of seven high grade tumours but in no low grade tumours. There was no apparent correlation between staining for any of the three enzymes and survival. CONCLUSIONS: Both low and high grade endometrial stromal tumours express matrix metalloproteinases. MMP-3 and MMP-9 are expressed more diffusely in high grade than in low grade tumours. In the individual case, diffuse staining for MMP-2 appears to best characterise the high grade tumours. Thus staining for MMP-2 may aid in differentiating high grade from low grade tumours, and MMP-9 in differentiating normal endometrial stroma from low and high grade endometrial stromal sarcomas. MMP expression does not appear to predict disease outcome in endometrial stromal sarcoma.     

Mesenchymale Uterustumoren

Uterine stromal neoplasms are classified into endometrial stromal nodules and stromal sarcomas, as well as undifferentiated sarcomas. The two former groups demonstrate identical histological composition, consisting of small monomorphous cells with scant cytoplasm and round nuclei and typically contain numerous arteriolar-type vessels. Stromal tumors are distinct from stromal nodules by virtue of their myometrial and vascular invasion. Undifferentiated sarcomas consist of polymorphic cells and lack any cytological similarity to the stroma of normal proliferative endometrium. There is no smooth or striated muscle differentiation. Adenosarcomas are mixed neoplasms with a low grade stromal sarcoma component containing benign glands, which are surrounded by condensed neoplastic stroma. Typical uterine tumors resembling ovarian sex cord tumors (UTROSCT Type2) show predominant sex cord differentiation in a well circumscribed nodule. Focal sex cord differentiation may occur in stromal nodules and stromal sarcomas (UTROSCT Type2).     

Neoplasms of endometrial stroma: histopathologic and flow cytometric analysis with clinical correlation

Ten neoplasms of endometrial stroma (one stromal nodule, four endolymphatic stromal myoses, and five stromal sarcomas) were compared using clinical data as well as histopathologic and flow cytometric parameters. None of the patients with stromal nodules or endolymphatic stromal myosis had extrauterine disease at presentation or tumors displaying a mitotic rate greater than 10/10 hpf (high-power fields), nuclear pleomorphism, atypical mitotic figures, DNA aneuploidy, or a high proliferative index (greater than 10% S phase cells). The stromal nodules were circumscribed and behaved in a benign fashion. The patients with endolymphatic stromal myosis had infiltrative tumors that behaved as low-grade cancers with good responses to therapy. Four of the five patients with stromal sarcoma had extrauterine disease at presentation as well as tumors characterized by a mitotic rate much greater than 10 mitoses/10 hpf, nuclear pleomorphism, atypical mitotic figures, DNA aneuploidy, and a high proliferative index. These four patients had aggressive disease with poor response to therapy. The fifth of the stromal sarcomas had a high mitotic rate, but lacked the other features linked with aggressive behavior; this patient has responded well to treatment. The mitotic count may not be the most useful criterion for predicting biologic behavior in endometrial stromal tumors since it does not always reflect an increased rate of cell turnover as demonstrated by the percentage of cells in the S phase. DNA analysis by flow cytometry yields a more accurate picture of tumor behavior.