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.     

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.     

New developments in endometrial stromal sarcoma

Endometrial stromal tumours have been recently reclassified in the WHO 2014 Classification due to the discovery of new genetic fusions. This has enabled the subdivision of previously described undifferentiated endometrial sarcomas into the molecularly-defined high grade endometrial stromal sarcoma (HG ESS) and undifferentiated uterine sarcoma (UUS). In this review, we discuss the discoveries behind the 2014 Classification and its rationale, and give practical tips for diagnosis of these neoplasms, as well as discussing the differential diagnoses that one may consider.     

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.     

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.     

Endometrial stromal tumors: Diagnostic updates and challenges

Endometrial stromal tumors are rare uterine mesenchymal tumors of endometrial stromal origin. They are classified into endometrial stromal nodule, low-grade endometrial stromal sarcoma, high-grade endometrial stromal sarcoma, and undifferentiated uterine sarcoma by the current (2020) WHO classification. Correct diagnosis of endometrial stromal tumors is critical for proper patient management. However, due to infrequent encounters, overlapping morphological features and immunohistochemical profiles, the differential diagnoses among endometrial stromal lesions and their morphologic mimics are often challenging. Partially with our own experience, here we review and summarize the tumor morphology, immunohistochemical phenotype, as well as molecular feature of endometrial stromal tumors and key differential diagnoses, emphasizing the newest developments and their utilization in daily practice.     

Klinik der uterinen Sarkome

There are many common features between uterine sarcomas – leiomyosarcoma, endometrial stromal sarcoma, undifferentiated endometrial sarcoma and adenosarcoma –with regards to course, therapy and follow-up, such as post-menopausal bleeding or additional premenopausal bleeding, as well as rapid growth. There is a new staging system according to FIGO and new therapy recommendations according to NCCN. Prior to therapy, imaging staging of the pelvis, abdomen and chest should be carried out due to the frequency with which metastases are found at the time of diagnosis. In the case of disease spread in uterine sarcomas and malignant mixed tumors, good supportive therapy is a possible therapy option instead of chemo- or radiotherapy. The approach – observation, surgery, lymphonodectomy, mono- or polychemotherapy, radiotherapy, hormone therapy – is chosen according to the extent of spread and the resection status. Neoadjuvant therapies are not as yet established.     

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.     

Heterologous and rare homologous sarcomas of the uterine corpus: a clinicopathologic review

Pure sarcomas of the uterine corpus are uncommon, constituting less than 3% of all malignancies at this site, and most of them are leiomyosarcomas and endometrial stromal sarcomas. Rare histotypes of homologous sarcomas and heterologous sarcomas are occasionally encountered, and the absence of significant accumulated experience with these histotypes at this location may potentially raise diagnostic and patient management difficulties. In this article, the clinicopathologic attributes of all earlier reported sarcomas of the uterine corpus other than leiomyosarcomas and endometrial stromal sarcomas are summarized. Included are embryonal rhabdomyosarcoma, pleomorphic rhabdomyosarcoma, angiosarcoma, alveolar soft part sarcoma, malignant perivascular epithelioid cell tumors (PEComas), osteosarcoma, chondrosarcoma, liposarcomatous tumors, malignant extrarenal rhabdoid tumors, Ewing sarcoma/primitive neuroectodermal tumor, and other rare histotypes. Embryonal rhabdomyosarcoma (20%), Ewing sarcoma/primitive neuroectodermal tumor (17%), angiosarcoma (14%), and pleomorphic rhabdomyosarcoma (13%) appeared to be more common than the others, although there was no single overwhelmingly prevalent histotype in the group. A subset, including embryonal rhabdomyosarcoma, alveolar soft part sarcoma, and PEComas, peak in the premenopausal years, but most of the others were observed in postmenopausal women. Favorable outcomes have been reported for the patients diagnosed with alveolar soft part sarcoma, and the prognosis for their counterparts with PEComa remains a matter of debate. Multimodal therapeutic approaches to contemporary patients with embryonal rhabdomyosarcomas have resulted in significantly improved outcomes. Unfortunately, most of the other sarcomas have been associated with rapid tumor progression and unfavorable patient outcomes. The differential diagnosis for these sarcomas is often extensive and varies by histotype, but their accurate diagnosis fundamentally requires the careful exclusion of biphasic malignancies.     

CD10 is a sensitive and diagnostically useful immunohistochemical marker of normal endometrial stroma and of endometrial stromal neoplasms

AIMS: The CD10 antigen is expressed in acute lymphoblastic leukaemia and follicle centre cell lymphoma. A recent study investigating the expression of CD10 in a wide range of non-haematopoietic neoplasms found positive staining in a small number of endometrial stromal sarcomas as well as in normal endometrial stroma. The present study aimed to ascertain whether CD10 positivity is indeed found in normal endometrial stroma and endometrial stromal neoplasms. Staining of a range of tumours which can be confused morphologically with endometrial stromal neoplasms was also undertaken to ascertain whether antibodies against CD10 are of value in a diagnostic sense. METHODS AND RESULTS: Neoplasms included in the study were endometrial stromal nodule (n=1), low-grade endometrial stromal sarcoma (ESS) (n=13), high-grade ESS (n=6), mixed endometrial stromal-smooth muscle tumour (n=1), uterine cellular leiomyoma (n=10), uterine leiomyosarcoma (n=5), adult granulosa cell tumour (AGCT) (n=10), undifferentiated endometrial carcinoma (n=6), uterine carcinosarcoma with an endometrial stromal component (n=1) and type II uterine mesenchymal tumour with sex cord-like elements (n=1). Cases of proliferative (n=5), secretory (n=5) and atrophic (n=3) endometrium were also stained. There was positive staining of stroma but not of glands in all cases of non-tumorous endometrium. There was positive staining of the endometrial stromal nodule and of all low-grade ESS. Staining in these varied but was often diffuse and of moderate to strong intensity. There was positive staining of four of six high-grade ESS, but this was usually focal. There was also positive staining of the endometrial stromal component in the mixed endometrial stromal-smooth muscle tumour and in the uterine carcinosarcoma. Most cellular leiomyomas were completely negative although three exhibited weak positivity. There was some positivity, usually focal or weak, of three of five leiomyosarcomas. Most AGCT and undifferentiated carcinomas were completely negative although one case of each exhibited focal staining. There was focal staining of the type II uterine mesenchymal tumour with sex cord-like elements. CONCLUSION: CD10 is a reliable and sensitive immunohistochemical marker of normal endometrial stroma. Positivity, which is often strong and/or diffuse is found in endometrial stromal nodules and low-grade ESS. Positive staining with CD10, when strong and diffuse, may be useful in distinguishing these tumours from histological mimics, especially cellular leiomyoma and AGCT which are generally negative. In this situation, CD10 should be used as part of a panel which might include desmin and alpha-inhibin depending on the differential diagnosis considered. Positive staining with CD10 in a high-grade uterine sarcoma which is negative with muscle markers might indicate endometrial stromal differentiation and identify a group of neoplasms which it is correct to diagnose as high-grade ESS rather than undifferentiated uterine sarcoma.     

Endometrial stromal sarcoma: clinicopathological and immunophenotype study of 18 cases

Malignant tumors of the uterine corpus are uncommon. They originate from the endometrial stroma, smooth muscle, blood vessels, or from a mixture of them. The objective of this article was to know the frequency and the clinical, morphologic, and immunophenotype characteristics of the endometrial stromal sarcoma (ESS). We reviewed the cases of ESS observed from 2002 to 2008 at the Pathology Unit of the General Hospital of Mexico. The following data were analyzed: age, clinical stage, degree of differentiation, and immunophenotype. We found 18 cases, and the average age of patients was 48.6 years; 66% were in clinical stages 1 and 2. Fifteen cases (83.3%) were classified as low-grade sarcomas and 3 (16.6%) as high-grade or undifferentiated sarcomas. We determined immunohistochemical markers in 17 cases; receptors to estrogens were positive in 5 (29.4%) and to progesterone in 9 (52.9%). CD10 was expressed in 10 (58.8%) and p53 in 11 cases (64.7%). Two cases were associated to primary tumors of the ovary (papillary cystadenocarcinoma). In conclusion, ESS was present at 0.6% in our institution; and most were low grade. Expression of markers, such as p53, CD10, and hormonal receptors, was positive.     

Carbonic anhydrase isozymes II, IX, and XII in uterine tumors

Histopathological diagnostics of gynecological malignancies continues to be challenging despite the well established criteria. For example, the morphological distinction of uterine leiomyosarcoma from certain variants of benign leiomyoma can be difficult. Herein, we investigated the expression of Carbonic anhydrase (CA) II, IX, and XII in the normal endometrium, leiomyomas, uterine sarcomas, and endometrial adenocarcinomas using immunohistochemistry. These isozymes are considered promising diagnostic markers and therapeutic targets. The normal endometrium showed high CA XII expression, whereas the signals were lower in endometrial adenocarcinoma (p < 0.004). Only sporadic CA IX staining was found in the normal endometrium, whereas the enzyme was overexpressed in most cases of endometrial adenocarcinoma (p < 0.005). CA II expression was slightly weaker in the normal endometrium than that in the adenocarcinomas (p < 0.008). Positive immunostaining reactions for CAs were observed in the uterine sarcomas, whereas all leiomyomas were negative for CA II and XII. A comparison between leiomyomas and sarcomas showed statistically significant differences for all studied isozymes (p < 0.001). Our study shows that CA isozymes could together serve as histopathological biomarkers for differential diagnosis between uterine leiomyosarcoma and leiomyoma. In addition to being found in leiomyosarcomas, CA II and IX were overexpressed in endometrial adenocarcinoma, where they might regulate the pH of the tumor microenvironment.     

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.     

Expression of androgen receptors in benign and malignant endometrial stromal neoplasms

Several studies have shown that endometrial stromal neoplasms express estrogen and progesterone receptors (ER, PR). To our knowledge, the presence or absence of androgen receptors (AR) in these rare uterine neoplasms has not been investigated. Tumors (n=20)—3 endometrial stromal nodules, 14 low-grade endometrial stromal sarcomas (ESS, low grade), and 3 high-grade endometrial sarcomas (undifferentiated endometrial sarcoma, UES)—were studied. Immunohistochemical analyses for ER, PR, and AR were performed on formalin-fixed, paraffin-embedded archival material. Positive immunoreactions for ER and PR were observed in 14 (70%) and 17 (85%) cases, respectively. Furthermore, 9 cases (45%) were positive for AR. Among 17 ESS and UES cases, 7 (41%) revealed positivity for AR. Two of three benign stromal nodules were also positive for AR. Moreover, one of the three high-grade sarcomas (undifferentiated endometrial sarcoma) was negative for both ER and PR, but showed positive reaction for AR. In summary, ARs are expressed in 45% of endometrial stromal neoplasms. In addition to determination of ER and PR, the results of immunohistochemical examination of AR in these rare uterine tumors may have some impact on the postoperative management of the patients.     

Clinical Aspects of Uterine SarcomasKlinik der Uterussarkome

Uterine sarcomas constitute 1 % to 3 % of all uterine cancers. There are three main histological varieties: endometrial stromal sarcoma, leiomyosarcoma, and mixed mesodermal (Müllerian) sarcoma. The tumors are characterized by local aggressiveness and early dissemination. According to the literature, 5 year survival rates range from 3 to 75% (!).This wide range reflects great prognostic differences in the various histologic types. On the other hand it may be due to discrepancies in histopathological evaluation.Radical surgery is the most effective therapy. In early stages it leads to 5 year survival rates of up to 88%. Adjuvant irradiation may increase the control of disease in the pelvis but has proven to be of little influence on the final outcome. The histologic variants show great differences in radiosensitivity. In endometrial stromal sarcomas adjuvant radiation therapy apparently can improve the treatment results. By contrast mixed mesodermal sarcomas are highly radioresisteft.There is poor knowledge on the effectiveness of cytotoxic agents on uterine sarcomas. Objective remission of distant metastasis has been observed following treatment with cytotoxic antibiotics (Adriamycin).     

宫内膜活检或刮出物中子宫内膜间质肉瘤的诊断

目的：探讨宫内膜活检或刮出物诊断子宫内膜间质肉瘤的标准和鉴别诊断注意事项。方法：对９例临床和病理资料完整并经宫内膜活检或刮出物中确诊的子宫内膜间质肉瘤,对照其随后进行的子宫切除标本的蜡块,再次常规制片,ＨＥ染色,光镜进行对比观察。结果：９例宫内膜活检或刮宫标本中,有６例分化良好,酷似子宫内膜增生过长时的间质细胞。有３例分化差者,其中２例酷似恶性淋巴瘤,１例酷似多形肉瘤。９例均见簇状分布的子宫内膜螺     

Uterine sarcomas in Norway. A histopathological and prognostic survey of a total population from 1970 to 2000 including 419 patients

Aims:  To determine the frequency and survival of the various types of uterine sarcoma in the total population of Norway and evaluate histopathological prognostic factors in order to identify risk groups.
Methods and results:  Histopathological review of all uterine sarcoma cases reported to the Norwegian Cancer Registry during 1970–2000 was undertaken. Survival dates were provided by The Cancer Registry. Kaplan–Meier survival curves were generated. The log rank test was used for univariate analysis and a Cox proportional hazards regression model for multivariate evaluation of survival. Stage of disease was the most important prognostic factor for all tumour types. Tumour size and the mitotic index (MI) were significant prognostic factors ( P  < 0.0001) in leiomyosarcomas confined to the uterus and allowed for separation into three risk groups with marked differences in prognosis. The prognosis of endometrial stromal sarcomas confined to the uterus was related to MI ( P  < 0.0001) and tumour cell necrosis ( P  < 0.004). Combining these parameters allowed for separation into three risk groups with marked difference in prognosis. In adenosarcomas, tumour cell necrosis was the only significant prognostic factor.
Conclusions:  There are marked differences in survival between uterine sarcoma types. Leiomyosarcomas and endometrial stromal sarcomas can be divided into different groups.     

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).     

Proliferation, ploidy and prognosis in uterine smooth muscle tumours

DNA ploidy, mitotic rate (per 10 high power fields), mitotic index (per 1000 tumour nuclei), Ki-67 labelling index and S phase fraction were measured in 23 uterine leiomyosarcomas and 10 tumours of uncertain malignant potential. Correlations were calculated by Spearmann rank correlation. Univariate survival analysis was performed by log rank analysis and multivariate analysis performed by the Cox linear regression method. Ki-67 index and S phase fraction were significantly higher in leiomyosarcomas than in tumours of uncertain malignant potential. There was significant correlation between mitotic rate, mitotic index, Ki-67 index and S phase fraction in cases of leiomyosarcoma. Fifteen of 22 leiomyosarcomas and one of 10 tumours of uncertain malignant potential were DNA aneuploid. On univariate analysis of all the smooth muscle tumours, DNA ploidy, presence of significant nuclear atypia and presence of coagulative tumour cell necrosis were associated with outcome. Only DNA ploidy was associated with outcome in the group of leiomyosarcomas. On multivariate analysis of all of the smooth muscle tumours. DNA ploidy, age and grade of atypia were independently associated with outcome. No single factor was independently predicitive of outcome in the group of leiomyosarcomas. Alternative indices of cell proliferation correlate with mitotic rate in uterine leiomyosarcoma and do not provide additional useful prognostic information. DNA ploidy, age and grade of atypia are independently associated with outcome in uterine smooth muscle tumours and measurement of DNA ploidy may be useful in identification of cases with an adverse prognosis.     

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.