Expression of androgen receptors in benign and malignant endometrial stromal neoplasms

A randomized double-blind phase II study evaluating the role of maintenance therapy with cabozantinib in high-grade uterine sarcoma after stabilization or response to doxorubicin ± ifosfamide following surgery or in metastatic first line treatment (EORTC62113)

BACKGROUND

Uterine sarcomas are a group of rare tumors that include different subtypes. Patients with histopathological high-grade diseases are at high-risk of recurrence or progression, and have a poor prognosis. We aim to explore the most appropriate management in patients with uterine high-grade sarcomas.

PRIMARY OBJECTIVE

To assess the efficacy of maintenance treatment with cabozantinib in patients with high-grade uterine sarcomas who achieved clinical benefit after standard chemotherapy.

STUDY HYPOTHESIS

Maintenance treatment with cabozantinib after standard chemotherapy given as an adjuvant treatment after curative surgery, or in locally advanced or metastatic disease, increases progression-free survival compared with placebo TRIAL DESIGN: This is a randomized double blinded phase II trial.

MAJOR INCLUSION/EXCLUSION CRITERIA

The study is enrolling adult patients with high-grade undifferentiated uterine sarcomas, high-grade endometrial stromal sarcomas, high-grade leiomyosarcoma, and high-grade adenosarcoma, FIGO (Federation International gynecologue Obstétricien) stage II/III to IV in stable disease or who achieved complete or partial response with doxorubicin ± ifosfamide, who are assigned 1:1 to 60 mg daily cabozantinib (experimental arm) or placebo (control arm), as maintenance therapy. Exclusion criteria include low-grade sarcoma.

PRIMARY ENDPOINT

Progression-free survival at 4 months.

SAMPLE SIZE

The study plans to enroll 90 patients to allow the randomization of 54 patients to detect an improvement in 4-month progression-free survival from 50% to 80% with 15% significance level and 85% power. Estimated dates for accrual completion: recruitment for the trial started in February 2015, and has currently enrolled 83 patients, of whom 35 patients have been randomized. The end of recruitment is anticipated for December 2020.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, number NCT01979393.

Ovarian preservation for low-grade endometrial stromal sarcoma: a systematic review of the literature and meta-analysis

OBJECTIVE

To evaluate the effect of ovarian preservation on oncologic outcomes for women with low-grade endometrial stromal sarcoma of the uterus.

METHODS

A systematic search of the Medline, Embase, Cohrane, and Web of Science databases was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Studies including patients with low-grade endometrial stromal sarcoma who had hysterectomy were identified. Data on tumor recurrence and death rate were pooled using a random effects model.

RESULTS

A total of 17 studies met the inclusion criteria and reported on 786 patients. Based on available information, ovarian preservation was noted in 190 patients while 501 had bilateral salpingo-oophorectomy. A significantly increased tumor recurrence rate was observed in the ovarian preservation group (89/190, 46.8%) compared with the bilateral salpingo-oophorectomy group (121/501, 24.2%) (OR 2.70, 95% CI 1.39 to 5.28). Based on data from 162 patients, no difference in death rate was noted between the ovarian preservation (2/34, 5.9%) and bilateral salpingo-oophorectomy (9/128, 7%) groups (OR 0.80, 95% CI 0.18 to 3.47).

CONCLUSIONS

Approximately one-quarter of patients with low-grade endometrial stromal sarcoma were managed with ovarian preservation. These women experienced a higher recurrence rate. Hormone exposure may be responsible for this elevated risk. Given the apparent high salvage rate, however, ovarian preservation may be an option only in a well-informed patient population.

Low-Grade Endometrial Stromal Sarcoma - a Review

Like other uterine sarcomas, low-grade endometrial stromal sarcomas (LG-ESS) are a very rare tumor entity. In the past, research studies therefore discussed the various different types of the disease in combination. In addition, the classification of endometrial stromal tumors presented difficulties for quite some time so that in earlier studies it was not always possible to precisely distinguish between LG-ESS, high-grade endometrial stromal sarcoma, and undifferentiated uterine sarcoma. For LG-ESS, surgery with hysterectomy and adnexectomy is the first-line treatment. The benefits of lymphadenectomy and tumor debulking are unclear. Endocrine therapy with gestagens and aromatase inhibitors is under discussion to provide adjuvant treatment for patients with advanced stages of the disease. As radiotherapy only provides locoregional control, and in view of the usually good prognosis of patients with LG-ESS, its benefits need to be weighed against its side effects. In the case of recurrence, repeat surgery is the first choice. Further research studies viewing LG-ESS as a distinct entity are needed in order to improve treatment options for patients with LG-ESS.

Endometrial stromal tumors: the new WHO classification

Endometrial stromal tumors are rare uterine mesenchymal neoplasms that have intrigued pathologists for years, not only because they commonly pose diagnostic dilemmas, but also because the classification and pathogenesis of these tumors has been widely debated. The current World Health Organization recognizes 4 categories of endometrial stromal tumor: endometrial stromal nodule (ESN), low-grade endometrial stromal sarcoma (LG-ESS), high-grade endometrial stromal sarcoma (HG-ESS), and undifferentiated uterine sarcoma (UUS). uterine sarcoma. These categories are defined by the presence of distinct translocations as well as tumor morphology and prognosis. Specifically, the JAZF1-SUZ12 (formerly JAZF1-JJAZ1) fusion identifies a large proportion of ESN and LG-ESSs, whereas the YWHAE-FAM22 translocation identifies HG-ESSs. The latter tumors appear to have a prognosis intermediate between LG-ESS and UUS, which exhibits no specific translocation pattern. This review (1) presents the clinicopathologic features of endometrial stromal tumors; (2) discusses their immunophenotype; and (3) highlights the recent advances in molecular genetics which explain their pathogenesis and lend support for a new classification system.

Molecular mechanisms of endometrial stromal sarcoma and undifferentiated endometrial sarcoma as premises for new therapeutic strategies

Endometrial stromal sarcoma (ESS) and undifferentiated endometrial sarcoma (UES) are very rare gynecologic malignancies. Due to the rarity and heterogeneity of these tumors, little is known about their epidemiology, pathogenesis, and molecular pathology. Our previous studies have described deregulation of histone deacetylases expression in ESS/UES samples. Some of these enzymes can be inhibited by substances which are already approved for treatment of cutaneous T-cell lymphoma. On the basis of published data, they may also provide a therapeutic option for ESS/UES patients. Our review focuses on molecular mechanisms of ESS/UES. It describes various aspects with special emphasis on alteration of histone deacetylation and its possible relevance for novel therapies.

Diagnostic use of immunohistochemistry in uterine mesenchymal tumors

Immunohistochemistry may be helpful in the diagnosis of mesenchymal uterine tumors. This article reviews the immunoreactions used most frequently in the diagnosis of uterine smooth muscle tumors, endometrial stromal tumors, undifferentiated endometrial sarcomas, UTROSCTs, PEComas, adenomyomas, adenosarcomas and carcinosarcomas.

Recent developments in uterine mesenchymal neoplasms

Smooth muscle and endometrial stromal tumours represent the two most common uterine mesenchymal neoplasms that may present diagnostic dilemmas for the practising surgical pathologist. Recent changes in morphological and staging criteria, as well as the discovery of new immunohistochemical markers, have improved the diagnosis and classification of these tumours. We highlight the difficulty in distinguishing tumour cell necrosis from infarct-type necrosis and the limited utility of p16 immunohistochemical expression in the diagnosis of leiomyosarcoma. We also discuss the controversial use of mitotic activity and necrosis as prognostic factors in endometrial stromal sarcomas. Emerging genetic information has also greatly expanded our understanding of 'sarcomagenesis' in both tumour types and may provide insight into potential therapeutic targets for the treatment of leiomyosarcoma and endometrial stromal sarcomas, harboring MED12 (mediator complex subunit 12) mutations and recurrent gene rearrangements, respectively. In this review, we discuss the core updates in the diagnosis and classification of uterine leiomyosarcomas and endometrial stromal sarcomas, highlighting new and important molecular genetic findings that may drive pathogenesis.

Endometrial stromal sarcomas: a review of potential prognostic factors

Endometrial stromal tumors are uncommon mesenchymal tumors of the uterus. The classification of these tumors has evolved and the most current World Health Organization classification (2003) divides these neoplasms into: endometrial stromal nodule, low-grade endometrial stromal sarcoma, and undifferentiated endometrial sarcoma. The salient clinicopathologic features of these tumors are described, and a comprehensive review of literature pertaining to potential prognostic factors in endometrial stromal sarcomas is provided. Clinical factors, including age, race, parity and menopausal status, and pathologic factors, including tumor size, tumor stage, nuclear atypia, mitotic activity, tumor necrosis, lymphovascular space invasion, DNA ploidy and proliferative activity, and expression of hormone receptors, have been explored with varying outcomes. Surgicopathologic stage seems to be the most important prognostic factor in low-grade endometrial stromal sarcomas. The impact of other prognostic factors on survival is unclear or controversial, especially in patients with stage I tumors.

Clinical management of uterine sarcomas

Malignant pure mesenchymal uterine tumours encompass endometrial stromal sarcoma (ESS), uterine leiomyosarcoma, and undifferentiated sarcomas. This Review discusses pathology, preoperative diagnosis, and standard treatment of uterine leiomyosarcoma and low-grade ESS (distinct from undifferentiated uterine sarcomas), with an emphasis on targeted treatment. We show that several features on ultrasonography and MRI can raise suspicion of a uterine sarcoma; however, there are no pathognomonic features on any imaging technique. For both ESS and uterine leiomyosarcoma, hysterectomy with bilateral salpingo-oophorectomy, but without lymphadenectomy, is the standard surgical treatment for early stage disease. The clinical benefit of chemotherapy is limited, which underscores the importance of targeted therapy. ESS and uterine leiomyosarcoma are driven by different pathways, resulting in a different clinical behaviour. ESS typically is a hormone-sensitive tumour with indolent growth. Uterine leiomyosarcoma is notorious for its aggressive growth and poor outcome. Individualisation of treatment is mandatory, because randomised trials are almost non-existent. The progesterone and oestrogen receptors are clinically important targets for most primarily advanced or recurrent ESS and a subset of recurrent uterine leiomyosarcomas. Potential future targets and targeted treatments that are under investigation are presented for both entities.

Endometrial/ioid Stromal Tumors and Related Neoplasms of the Female Genital Tract

Endometrial/ioid stromal tumors comprise a spectrum of mesenchymal neoplasms, ranging from benign to low-grade malignancy to undifferentiated sarcomas, which occur predominantly in the uterus but may rarely originate at extrauterine sites, most commonly in the ovary. These tumors and their morphologic variants are important to recognize as they often cause diagnostic difficulties. This review focuses on the diagnostic criteria and differential diagnosis, including the role of immunohistochemistry.

Molecular Genetics of Mesenchymal Tumors of the Female Genital Tract

Mesenchymal tumors of the female genital tract are a heterogeneous group of neoplasms that can be classified based on cellular differentiation into 3 main groups: smooth muscle tumors, endometrial stromal tumors, and other differentiated and undifferentiated tumors. Genomic analysis techniques have revealed important genetic aberrations such as the t(7;17) translocation, resulting in JAZF1-JJAZ1 gene fusion, characteristic of endometrial stromal tumors. These analyses have demonstrated genetic complexity and heterogeneity in many mesenchymal tumor types. This article focuses on current understanding of the molecular genetics of mesenchymal tumors of the female genital tract, with emphasis on diagnostic and prognostic molecular features.

Immunohistochemical Markers of Value in the Diagnosis of Mesenchymal Lesions of the Female Genital Tract

Pure mesenchymal tumors may occur anywhere in the female genital tract, but they are most common in the uterine corpus, leiomyoma being by far the most prevalent. These tumors, and other uncommon mesenchymal lesions within the uterine corpus and elsewhere in the female genital tract, may result in several diagnostic problems. Morphology remains paramount and, in most cases, an unequivocal diagnosis can be made based on examination of the hematoxylin and eosin stained sections, combined with an appreciation of the clinical and gross pathologic features. In difficult cases, immunohistochemistry can significantly contribute to the final diagnosis. In this article, the immunohistochemistry of neoplastic and nonneoplastic mesenchymal lesions of the female genital tract is discussed site by site, concentrating on markers that are of value in diagnosis and in differential diagnosis. The immunophenotype of mixed epithelial and mesenchymal neoplasms and pure epithelial neoplasms with a component of spindle cells is discussed, where appropriate, because these can enter into the differential diagnosis of a pure mesenchymal lesion.

Androgen receptor expression in gastrointestinal stromal tumor

The aim of this study was to evaluate the expression of estrogen, progesterone, and androgen receptors in a large series of gastrointestinal stromal tumors. Clinical and pathologic data were reviewed in 427 cases of gastrointestinal stromal tumor and the expression of such hormone receptors was investigated by immunohistochemistry using tissue microarray technique. All tumors were negative for estrogen receptor expression. Progesterone and androgen receptors expression was observed in 5.4% and 17.6% of tumors, respectively. We found the higher average age at diagnosis, the lower frequency of tumors located in the small intestine, and the higher frequency of extragastrointestinal tumors to be statistically significant in the group of tumors with androgen receptor expression in contrast to the group showing no androgen receptor expression. There was no statistic difference between such groups regarding sex, tumor size, mitotic count, cell morphology, and risk of aggressive behavior. Considering that the expression of androgen receptors in gastrointestinal stromal tumors is not negligible, further studies are encouraged to establish the role of androgen deprivation therapy for gastrointestinal stromal tumors.

[Mesenchymal uterine tumors. Stromal tumors and other rare mesenchymal neoplasms]

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).

Treatment of early uterine sarcomas: disentangling adjuvant modalities

Uterine sarcomas are a rare group of neoplasms with aggressive clinical course and poor prognosis. They are classified into four main histological subtypes in order of decreasing incidence: carcinosarcomas, leiomyosarcomas, endometrial stromal sarcomas and "other" sarcomas. The pathological subtype demands a tailored approach. Surgical resection is regarded as the mainstay of treatment. Total abdominal hysterectomy and bilateral salpingo-oophorectomy represents the standard treatment of uterine sarcomas. Pelvic and para-aortic lymph node dissection in carcinosarcomas is recommended, given their high incidence of lymph node metastases, and may have a role in endometrial stromal sarcomas. Adjuvant radiation therapy has historically been of little survival value, but it appears to improve local control and may delay recurrence. Regarding adjuvant chemotherapy, there is little evidence in the literature supporting its use except for carcinosarcomas. However, more trials are needed to address these issues, especially, their sequential application. Patients with uterine sarcomas should be referred to large academic centers for participation in clinical trials.

Calretinin: diagnostic utility in the female genital tract

The utility of calretinin was first described in the diagnosis of mesothelioma. In the female genital tract, calretinin was initially reported in Wolffian remnants and related lesions and later used in the diagnosis of sex cord stromal tumors of the ovary, endometrial stromal tumors with sex cord-like differentiation, and uterine tumors resembling sex cord tumors of the ovary. This review discusses calretinin expression in normal tissues of the female genital tract and highlights its potential utility in the diagnosis of these subsets of neoplasms with emphasis to tumors that may constitute a problem in their differential diagnosis. In particular, the limited utility of calretinin in the diagnosis of sex cord stromal tumors of the ovary, in the differential diagnosis between mesothelioma and serous tumors involving the ovary and/or peritoneum, and in the differential diagnosis between Wolffian lesions and endometrial carcinoma are addressed.

Mullerian adenosarcomas: an immunophenotypic analysis of 35 cases

Mullerian adenosarcomas (MAs) are rare mixed mesenchymal and epithelial neoplasms that occur most commonly in the uterus. Although the epithelial component is typically benign, the mesenchymal component of most adenosarcomas morphologically resembles that observed in endometrial stromal tumors and is responsible for their clinical behavior. Thus, the differential diagnosis usually includes not only low-grade endometrial stromal tumors, but also adenofibroma, carcinosarcoma, and embryonal rhabdomyosarcoma especially in small samples. The objective of this study was to ascertain the immunophenotypic profile of the epithelial and mesenchymal components of MAs and delineate possible differences between conventional mesenchymal areas and areas of sarcomatous overgrowth. Representative sections from 35 MAs, 28 of them without sarcomatous overgrowth (MA-NSO) and 7 with sarcomatous overgrowth (MA-SO), were included in the study. Thirty tumors arose in the uterus, 4 were pelvic, and 1 originated in the colon. Adequate blocks were selected and immunostained for estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), CD10, WT1, smooth muscle actin, desmin, AE1/3 cytokeratin, CD34, calretinin, inhibin, c-kit, and Ki-67. The mesenchymal component expressed ER in 21/27 MA-NSOs but in only 1/7 MA-SOs (65% overall). PR was expressed in 21/26 MA-NSOs and 4/7 MA-SOs (76% overall), whereas AR was positive in 10/27 MA-NSOs and 5/7 MA-SOs (35% overall). CD10 was expressed in 23/28 MA-NSOs but in only 2/7 MA-SOs (71% overall), and WT1 positivity was seen in 22/27 MA-NSOs and 6/7 MA-SOs (79% overall). Sixty-seven percent of MAs expressed smooth muscle actin, 32% desmin, including both examples of MA-SOs with rhabdomyoblastic differentiation, and 25% expressed AE1/3 cytokeratin. CD34 expression was found in 35% of the tumors, but it was almost always patchy in distribution and weak in intensity, as was calretinin expression, seen only in 12% of the cases. Expression of c-kit and inhibin in greater than 5% of the tumor cells was not encountered. The median and mean Ki-67 labeling indices were 10% and 12%, respectively (range, <5% to 40%). The median and mean Ki-67 indices were both 5% in MA-NSOs compared with 30% and 28%, respectively, in MA-SOs. The epithelial compartment demonstrated expression for ER (24/32), PR (23/31), and AE1/3 cytokeratin (33/33); rare cases expressed CD10 (4 cases) and AR (1 case). In summary, the immunophenotype of most MAs resembled that of endometrial stromal tumors (positive for ER, PR, WT1, and CD10, with variable expression of muscle markers, AR and cytokeratin). The proliferative rate in the stromal component was strongly related to the presence of sarcomatous overgrowth. ER, PR, and CD10 expression was lost in MA-SOs relative to conventional low-grade stromal areas of mullerian/mesodermal adenosarcomas, reflecting the "dedifferentiation" of this component.

Immunoexpression of androgen receptor in the nontumorous pituitary and in adenomas

Little information is available regarding androgen receptor immunoexpression (AR) in the normal and neoplastic human pituitary. Available experimental data links it to primarily gonadotroph cells. We undertook an immunohistochemical study of 41 autopsy-derived normal glands from patients of both sexes and all ages as well as 79 fully characterized pituitary adenomas of all types, the focus being upon AR expression in normal and neoplastic gonadotrophs. Nuclear AR immunoreactivity was noted in gonadotrophs and other normal adeno- and neurohypophysial cells. In addition to its presence in 74% of gonadotroph and 55% of null cell adenomas, lesser proportions of other adenoma types (adrenocorticotropic hormone 50%, prolactin 38%, growth hormone 33%) also exhibited AR immunoreactivity. No staining of thyroid-stimulating hormone adenomas was noted. The physiologic significance of our findings remains to be explored. The literature regarding AR expression in animal and human pituitaries is reviewed.

Uterine sarcomas

A wide variety of sarcomas occur in the uterus but two subtypes - leiomyosarcoma and endometrial stromal sarcoma - account for a majority of those more routinely encountered. Using the 2003 World Health Organization classification, this review focuses on six uterine sarcomas: endometrial stromal sarcoma, undifferentiated endometrial sarcoma, leiomyosarcoma, rhabomyosarcoma, angiosarcoma and liposarcoma. The epidemiological, clinical, pathological and molecular features are presented along with therapeutic approaches. Familiarity with molecular aspects of these tumors and application of novel technologies in their assessment should be encouraged as they may provide alternate therapies resulting in improved survival for the patient. Clinical information necessary for accurate diagnosis of these lesions is emphasised. A multidisciplinary approach to management of patients with uterine sarcomas is essential for optimal management.

Molecular genetic changes in epithelial, stromal and mixed neoplasms of the endometrium

Endometrial carcinoma, endometrial stromal tumours and mixed malignant mesodermal tumours (MMMT) develop along distinctive molecular genetic pathways. Two distinctive types of endometrial carcinoma are distinguished, type I and type II, which develop along distinctive pathways and show different clinical behaviour and histological features. Type I carcinomas show endometrioid histology, are oestrogen-related and develop from atypical endometrial hyperplasia. The molecular tumorigenesis is comparable to colorectal carcinoma with a step-like progression and an accumulation of genetic alterations. Alterations of PTEN, K-Ras mutations and microsatellite instability are frequent and early events in type I carcinoma, whereas p53 mutations occur during progression to grade 3 carcinoma. Serous and clear cell carcinomas are considered type II carcinomas which are mostly unrelated to oestrogen. p53 mutations occur in almost all serous carcinomas and seem to occur early, leading to massive chromosomal instability and rapid tumour progression. Gene expression profiling has supported this dualistic model of endometrial carcinoma. There is evidence of molecular differences between serous and clear cell carcinomas as well as between endometrioid carcinomas with and without microsatellite instability. A dualistic model of tumorigenesis may be also suggested for endometrial stromal tumours. Endometrial stromal sarcomas (ESS; type I endometrial sarcoma) are oestrogen-related and seem to develop from endometrial stromal nodules (ESN). They are histologically and genetically distinct from undifferentiated endometrial sarcoma (UES) which seem to be mostly unrelated to oestrogen (type II endometrial sarcoma). ESS and ESN share the fusion gene JAZF1/JJAZ1 caused by a t(7;17)(p15;q21) translocation, whereas UES lacks a distinctive molecular alteration so far. In MMMT, which is considered a metaplastic carcinoma, p53 alteration occurs early, before clonal expansion and acquisition of genetic diversity during progression.

Identification and meta-analysis of a small gene expression signature for the diagnosis of estrogen receptor status in invasive ductal breast cancer

In breast cancer, the determination of estrogen receptor (ER) expression is crucial for the decision on therapeutic strategies. Current ER expression analysis is based on immunohistochemical (IHC) staining of ER on formalin fixed tissue sections. However, low levels of ER expression frequently escape detection because of varying sensitivities of routine histopathological laboratories. Moreover, in estimating ER by IHC the receptor protein only is tested instead of the complex underlying ER pathway, which reflects its biological activity. To overcome this limitation, we have used the microarray technology to study 56 samples of invasive ductal carcinoma. We infer a robust and reliable signature of 10 genes, which is associated with ER expression and presumably therapeutically relevant biological processes. In a meta-analysis, the signature was tested on 3 further independent microarray gene expression data sets, covering different laboratories, array platforms, and clinics. The classification based on the signature showed a very low misclassification rate. In summary, the expression of few genes is sufficient to determine ER status. Future decisions on antiestrogen based therapy in breast cancer could be based on this signature rather than on immunostaining alone.

Uterine tumour resembling ovarian sex cord tumour is an immunohistochemically polyphenotypic neoplasm which exhibits coexpression of epithelial, myoid and sex cord markers

AIMS

To describe the clinicopathological and immunohistochemical findings in four cases of uterine tumour resembling ovarian sex cord tumour (UTROSCT).

METHODS

Four UTROSCTs were stained with a wide range of antibodies, including epithelial (AE1/3, epithelial membrane antigen), myoid (desmin, alpha smooth muscle actin, h-caldesmon), sex cord (alpha inhibin, calretinin, melan A, CD99) and neuroendocrine (chromogranin, CD56) markers as well as hormone receptors (oestrogen receptor, progesterone receptor, androgen receptor), vimentin, CD10, WT1 and HMB45.

RESULTS

The tumours ranged from 0.8 to 19.5 cm. Three were relatively well circumscribed intramural myometrial lesions; the other was a pedunculated mass attached to the uterine serosa. The tumours were variably composed of solid, corded, trabecular, nested, glandular and retiform arrangements of tumour cells. In three cases, cells with eccentric nuclei and abundant eosinophilic cytoplasm, resulting in a rhabdoid appearance, were a prominent feature. Three cases were diffusely positive with AE1/3 and all with epithelial membrane antigen. Positivity with myoid markers was common with 3, 4 and 1 case respectively staining with desmin, alpha smooth muscle actin and h-caldesmon; 2, 4, 1 and 2 cases respectively were positive with alpha inhibin, calretinin, melan A and CD99. All were chromogranin negative and exhibited diffuse strong staining with CD56. All were diffusely positive with oestrogen receptor, progesterone receptor, vimentin and WT1. Three cases were androgen receptor positive and all were CD10 and HMB45 negative.

CONCLUSIONS

UTROSCT exhibits a polyphenotypic immunophenotype with coexpression of markers of epithelial, myoid and sex cord lineage as well as hormone receptors.

Immunohistochemical and functional biomarkers of value in female genital tract lesions

There has been a marked expansion in the literature pertaining to the use of immunohistochemical markers in female genital tract pathology, especially with regard to diagnosis. This review provides a survey of the antibodies commonly used in the diagnosis of gynecological lesions grouped as to function or type. Prognostic or predictive markers are also discussed where appropriate, although few of these are of value in everyday practice. It is stressed that when immunohistochemistry is used diagnostically, panels of markers provide better information than reliance on a single antibody.

Phenotypic characterization of endometrial stromal sarcoma of the uterus

Endometrial stromal sarcoma (ESS) of the uterus is a rare uterine malignancy that has not been characterized in detail. To characterize the phenotype of ESS of the uterus, we extracted RNA from ESS and the stroma of normal endometrium using a tissue microdissection system and compared the expression profiles in the two tissues. After suppression subtractive hybridization and differential screening, we detected the metastasis-associated lung adenocarcinoma transcript 1 (MALAT-1) gene as one of the major genes upregulated in ESS, and a full-length placental cDNA clone (CS0DI066YJ10) as one of the major genes downregulated. The results were confirmed by in situ hybridization in four resected specimens of ESS and 36 biopsy specimens of normal endometrial tissue. All ESS (4/4) and all cases of endometrial stromal cells in the proliferative phase (13/13) were positive for MALAT-1, but samples of normal stroma in the secretory phase and menopausal state included some that were negative or weakly positive for MALAT-1 (5/13 and 3/10, respectively). In contrast, all ESS and 12 of 13 cases of stromal cells in the proliferative phase were negative for the full-length placental cDNA clone but 10 of 13 cases of endometrial stromal cells in the secretory phase were positive for transcripts of the gene (P < 0.05). These results indicated that endometrial stromal cells have different phenotypic characteristics between proliferative and secretory phases and the tumor cells of ESS have the phenotypic character of endometrial stromal cells in the proliferative phase.

Endometrial Stromal Sarcomas Frequently Express Epidermal Growth Factor Receptor (EGFR, HER-1)

Endometrial stromal sarcomas are rare malignant mesenchymal uterine tumors. The expressions of different epidermal growth factor receptors such as EGFR (HER-1), HER-2, HER-3, and HER-4 have not yet been examined in these tumors. Twenty-three cases of endometrial sarcomas consisting of 20 low-grade endometrial stromal sarcomas and 3 undifferentiated endometrial sarcomas were examined immunohistochemically for EGFR (HER-1), HER-2, HER-3, and HER-4. EGFR (HER-1) was positive in 17 of 23 (74%) cases. While the three undifferentiated endometrial sarcomas were positive for EGFR, 14 of 20 (70%) low-grade endometrial stromal sarcomas showed positive reactions for EGFR. All examined cases were negative for HER-2, HER-3, and HER-4. This study is the first to show common expression of EGFR (HER-1) in endometrial stromal sarcomas. This finding may provide the basis for a new therapeutic strategy using monoclonal antibodies against EGFR (such as cetuximab) or small molecule inhibitors of EGFR (such as gefitinib) in patients with endometrial sarcomas.