Poly(ADP-ribose) polymerase (PARP) and DNA-fragmentation factor (DFF45): expression and correlation in normal, hyperplastic and neoplastic endometrial tissues

This study evaluated the immunohistochemical expression of poly(ADP-ribose) polymerase (PARP) and DNA fragmentation factor 45 (DFF45) in normal endometria (NE, n=13), non-atypical (NAH, n=22) and atypical hyperplasia (AH, n=14), endometrioid carcinoma (EC, n=34), serous carcinoma (SC, n=10), and clear cell carcinoma (CCC, n=2). With regard to quantity and intensity of positively stained cells, immunostaining was scored as negative, low, and strong. Nuclear PARP immunoreactivity was found in all cases. If present, DFF45 immunoreactivity was detected predominantly in the nucleus and to some extent in the cytoplasm. PARP immunoreactivity increased significantly from NE via NAH to AH (P=0.0004), and decreased from AH to endometrial carcinomas (P=0.0054). DFF45 immunoreactivity increased significantly from NE to NAH and to AH (P=0.0009). No significant differences were calculated between AH and endometrial carcinomas (P=0.7495). FIGO stages and tumor grades could not be characterized by PARP and DFF45 immunoexpression (P=1.000 and 0.7383, as well as P=0.3034 and 0.7533, respectively). Pearson correlation revealed significant associations of PARP and DFF45 immunoscores for all diagnostic categories of NE, NAH, AH, EC, and SC/CCC. Immunoexpression of PARP and DFF45 is apparently altered in endometrial carcinomas as compared with non-neoplastic endometrial tissues, indicating impaired mechanisms of apoptosis in the former.     

Promoter hypermethylation and expression of sprouty 2 in endometrial carcinoma

Sprouty 2 is a key antagonist regulator of receptor tyrosine kinases, and downstream signaling pathways, like fibroblastic growth factor (FGF) and Ras-mitogen-activated protein kinase (RAS-MAPK). By controlling these pathways, sprouty 2 is involved in regulation of cell proliferation, differentiation, and angiogenesis. Alterations in fibroblastic growth factor receptor (FGFR) and members of the RAS-MAPK pathway are frequent in endometrial carcinoma. The expression of sprouty 2 has been found to be decreased in several types of human cancer, by mechanisms of promoter methylation. In the present study, we have assessed the expression of sprouty 2 in endometrial carcinoma, in correlation with sprouty 2 promoter methylation. Sprouty 2 immunohistochemical expression was assessed using 3 different tissue microarrays: one constructed from paraffin blocks of 80 samples of normal endometrium and 2 tissue microarrays containing samples of 157 endometrial carcinoma (1 tissue microarray constructed with 95 endometrial carcinomas previously studied for microsatellite instability and alterations in phosphatase and tensin homolog (PTEN), k-ras, and b-catenin, and 1 tissue microarray containing 62 endometrial carcinoma, which were also subjected to sprouty 2 promoter methylation analysis). The immunohistochemical expression of sprouty 2 was correlated with cellular proliferation (Ki67) and clinicopathologic data. Sprouty 2 promoter methylation was assessed by methylation-specific polymerase chain reaction, with DNA obtained from fresh-frozen samples of endometrial carcinoma and corresponding normal tissues, and correlated with promoter methylation of RAS association domain family-1A (RASSF1A). A highly significant decrease in sprouty 2 immunoexpression was seen in the proliferative phase of normal endometrium (P < .001). Differences were detected between types I and II endometrial carcinoma, but they were not statistically significant. Reduced immunoexpression of sprouty 2 was seen in 19.85% of endometrial carcinoma and was strongly and inversely associated with increased cell proliferation (Ki67; r = -0.367; P = .001). Sprouty 2 promoter methylation was detected in 31 (53.4%) of 58 endometrial carcinomas. Results from our study show that alterations in sprouty 2 may be involved in endometrial carcinogenesis by controlling cell proliferation.     

beta-Catenin expression pattern, beta-catenin gene mutations, and microsatellite instability in endometrioid ovarian carcinomas and synchronous endometrial carcinomas.

beta-Catenin gene mutations and microsatellite instability (MI) have been reported in endometrioid ovarian carcinomas. In colon but not endometrial cancer, beta-catenin gene mutations are associated with a replication error phenotype and MI. In this study the authors investigate whether beta-catenin mutations and MI are two independent oncogenic pathways in endometrioid ovarian carcinomas. They also evaluate the usefulness of these molecular markers in determining the primary origin of simultaneous tumors in the ovary and endometrium. This study was performed on 26 patients diagnosed with primary endometrioid ovarian carcinoma, five of whom also had pathologically diagnosed primary synchronous endometrioid endometrial carcinoma. Immunohistochemical and molecular analyses indicated that there were 25 primary ovarian tumors with four primary synchronous endometrial cancers and one ovarian metastasis of a primary endometrial carcinoma. All studies were performed on formalin-fixed, paraffin-embedded tissue samples. The beta-catenin expression pattern (nuclear vs. membranous) was analyzed immunohistochemically. Mutations in exon 3 of the beta-catenin gene were studied by polymerase chain reaction, single-strand conformational polymorphism, and direct sequencing. MI status was established by studying BAT-26 and BAT-25 mononucleotide repeats. In the group with 21 single ovarian tumors, 18 (85%) had beta-catenin nuclear expression, eight (38%) had beta-catenin gene mutations (always associated with beta-catenin nuclear expression), and four (19%) had MI. Only one case (5%) had both beta-catenin gene mutations and MI. The mutations affected one of the serine/threonine residues targeted for phosphorylation by glycogen synthase kinase-3beta or adjacent residues. At codon 32, a GAC-to-TAC (D32Y) change was found; at codon 33, two TCT-to-TGT (S33C) changes were found; at codon 37, three TCT-to-TTT (S37F) changes and one TCT-to-TGT (S37C) change were found; and, lastly, one ACC-to-GCC change at codon 41 (T41A) was detected. Four of the 25 endometrioid ovarian carcinomas (16%) had an associated synchronous endometrial carcinoma. There was a higher percentage of beta-catenin mutations (n = 3, 75%) in synchronous ovarian carcinomas than in single ones, although with a similar percentage of MI (n = 1, 25%). beta-catenin mutations were S37C in two cases and D32G in one. One of the four endometrial carcinomas showed an S33C beta-catenin mutation, and two carcinomas had MI. None of the four tumors had both beta-catenin gene mutation and MI. beta-catenin gene mutations were always associated with a nuclear beta-catenin expression pattern, whereas MI was associated with a membranous pattern. In one patient both the ovarian and the endometrial carcinomas had beta-catenin gene mutations, in another patient both tumors showed MI, whereas in the remaining two patients the ovarian carcinomas showed beta-catenin gene mutations and the endometrial carcinomas showed MI. To summarize, the results of this study suggest that beta-catenin mutations and MI could represent two independent pathways in endometrioid ovarian carcinomas because they occur simultaneously very infrequently (in 5% of these cases). beta-catenin mutations are always associated with a nuclear beta-catenin expression pattern, whereas cases with a replication error -plus phenotype showed no abnormal beta-catenin subcellular localization. The study of the beta-catenin expression pattern, beta-catenin mutations, and MI, together with conventional clinicopathologic findings, could aid in distinguishing between the metastatic or independent origin of simultaneous endometrioid ovarian and endometrial carcinomas. Tumors with identical immunohistochemical and molecular features should therefore be considered to have a common origin.     

The mucin expression profile of endometrial carcinoma and correlation with clinical-pathologic parameters.

Mucin expression patterns have been studied in tumors from various sites. Previous studies have shown an association of MUC1 with poor prognosis and MUC2 and MUC5AC with a mucinous phenotype. The pattern of mucin expression in endometrial carcinomas has not been documented in a large series. We determined the mucin expression profile in endometrial carcinomas and evaluated the relationship between mucin expression and clinical-pathologic parameters. A tissue microarray of 310 cases of endometrial carcinoma with known clinical outcome was constructed from formalin-fixed, paraffin-embedded donor blocks using two 0.6 mm cores from each tumor. Sections were stained with monoclonal antibodies against MUC1, MUC2, MUC4, MUC5AC, and MUC6. Staining was considered positive if greater than or equal to 5% of cells stained positively in either core. Mucin expression was correlated with tumor type, histologic grade, International Federation Gynecology and Obstetrics stage, lymph node involvement, depth of myometrial invasion, patient age, ethnicity, and clinical outcome. MUC1 was expressed in 267/310 (86.1%) of endometrial carcinomas, MUC2 in 2/310 (0.6%), MUC4 in 73/310 (23.5%), MUC5AC in 1/310 (0.3%), and MUC6 in 4/310 (1.2%). Endometrioid endometrial carcinoma showed a higher rate of MUC1 expression than nonendometrioid endometrial carcinoma (227/258, 88.0% vs. 39/52, 75.0%, P=0.01). No significant differences in any of the mucins were noted among the other end points evaluated. Mucin expression did not correlate with tumor grade, stage, or patient outcome.     

Promoter hypermethylation and reduced expression of RASSF1A are frequent molecular alterations of endometrial carcinoma.

Alterations in the regulation of the RAS-MAPK pathway are frequent in endometrial carcinoma. RASSF1A is a tumor-suppressor gene that can regulate this pathway negatively. RASSF1A has been found to be inactivated by promoter methylation in some human tumors. The aim of the study was to assess the immunohistochemical expression of RASSF1A in normal endometrium and endometrial carcinoma, and to correlate its expression with K-RAS mutations, presence of microsatellite instability, RASSF1A promoter methylation, and clinicopathological data. RASSF1A immunostaining was evaluated in one tissue microarray constructed from 80 paraffin-embedded samples of normal endometrium, and two tissue microarrays constructed with a total of 157 endometrial carcinomas (one constructed with 95 endometrial carcinomas previously evaluated for K-RAS mutations, and microsatellite instability, and another one containing 62 endometrial carcinomas that were also subjected to RASSF1A promoter methylation analysis). RASSF1A immunostaining was correlated with cell proliferation (Ki67), Cyclin D1 expression and clinicopathological data. Promoter methylation of RASSF1A was assessed by methylation-specific PCR. RASSF1A immunostaining was variable during the menstrual cycle in normal endometrium. RASSF1A expression was significantly reduced in 48% of endometrial carcinomas, particularly in tumors exhibiting microsatellite instability. RASSF1A-promoter methylation was very frequent in endometrial carcinoma (74%), and was frequently associated with reduced expression of RASSF1A. RASSF1A-promoter hypermethylation was common in advanced-stage endometrial carcinoma. The results suggest that reduced expression of RASSF1A may play a role in endometrial carcinogenesis by controlling cell proliferation and apoptosis through the MAPK-signaling pathway.     

Human papillomavirus and c-myc/c-erbB2 in uterine and vulvar lesions

Summary The aim of this study was to investigate papillomavirus (HPV)-DNA in precancer and cancer of the cervix, vulva, and endometrium by in situ/dot blot/ Southern blot hybridization and polymerase chain reaction (PCR).Myc/erbB-2 expression was examined by Northern blot analysis. PCR was the most sensitive HPV detection method, demonstrating HPV-DNA in all preinvasive and invasive cervical lesions (n=21) and most (3 of 4) vulvar carcinomas in contrast to an overall rate of 60% with other techniques. Particular phenotypes (adenoid cystic/basal cell carcinoma of the vulva, cervical adenocarcinoma) were found to contain HPV. Endometrium harboured HPV not only in two cases of cervical cancer, but also in 3 of 8 primary endometrial carcinomas and 3 of 8 non-malignant conditions. activation was confined to three squamous cell carcinomas, most markedly in one HPV-6-positive verrucous variant.ErbB-2 over-expression was only seen in one HPV-18 infected advanced endometrial tumour. Our findings point to a range of HPV-infected lesions broader than previously supposed and possible contributions of HPV-independent molecular events to carcinogenesis in this field.     

Immunohistochemical analysis of steroid receptors, proliferation markers, apoptosis related molecules, and gelatinases in non-neoplastic and neoplastic endometrium

Endometrioid endometrial carcinoma developed from endometrial hyperplasia is associated with anomalies of proliferation, apoptosis, and matrix metalloproteinase (MMP) expression. Our study was designed to investigate steroid receptor (ER, PR) expression and its correlation with proliferative activity (PCNA), apoptosis (Fas, FasL, Bcl-2, Bax, and p53), gelatinases (MMP-2 and MMP-9) and their tissue specific inhibitor (TIMP-1 and TIMP-2) immunoexpression in endometrial carcinogenesis. A total of 38 cases were investigated, 10 non-neoplastic, 11 hyperplastic, and 17 carcinomatous endometria. Immunolabeling showed a higher expression of steroid receptors in hyperplasia and carcinoma than in non-neoplastic endometria and an ER/PR imbalance in carcinoma. The epithelial component of endometrial carcinomas had the highest proliferative index. Bcl-2 had a stronger expression in hyperplasia and carcinoma compared to non-neoplastic endometria and stromal tissue. The Bcl-2/Bax ratio was lower in endometrial carcinoma. Fas and FasL expression was stronger in hyperplasia and furthermore in carcinoma. p53 expression was progressively stronger along the sequence non-neoplastic endometrial to hyperplasia-carcinoma. Both types of investigated MMPs showed an increased expression in neoplastic endometria reaching a maximum level in carcinomas. MMP-9 immunostaining could be correlated to myometrial invasion. TIMP-1 decreased and TIMP-2 increased in expression from non-neoplastic endometria to hyperplastic and carcinomatous endometrial, respectively. Our study demonstrates that coordinated anomalies of steroid receptors, apoptosis and invasiveness factors are already present in hyperplasia as cumulative steps along the way to malignant transformation and that a complex MMP-2, MMP-9, TIMP-2/TIMP-1 imbalance seems to be responsible for the endometrial proliferation.     

HMGA2 is commonly expressed in uterine serous carcinomas and is a useful adjunct to diagnosis

McCluggage W G, Connolly L E, McBride H A, Kalloger S & Gilks C B (2012) Histopathology  60, 547–553
HMGA2 is commonly expressed in uterine serous carcinomas and is a useful adjunct to diagnosis Aims: Serous carcinoma is the prototype of type 2 uterine carcinoma. In many cases, establishing a diagnosis is straightforward, but problems can arise in that papillary variants of endometrioid carcinoma may be mistaken for serous carcinoma, and glandular variants of serous carcinoma may be misdiagnosed as endometrioid carcinoma. Markers such as p53, oestrogen receptor and p16 may be of use in problematic cases, but there is overlap and these may not therefore be of value in an individual case. It has been shown recently that high‐mobility group AT‐hook 2 (HMGA2) is expressed by most ovarian serous carcinomas, and our aim was to ascertain whether it is also expressed in uterine serous carcinoma and of value in its distinction from endometrioid carcinoma. Methods and results: Whole tissue sections of uterine serous (n = 33) and endometrioid (n = 38) carcinoma were immunostained using HMGA2 antibody. As many of the diagnostic problems relate to the distinction between serous carcinoma and grade 3 endometrioid carcinoma, tissue microarrays (TMAs) containing uterine serous (n = 71) and uterine grade 3 endometrioid (n = 68) carcinomas were also stained. Staining was classified as negative (totally negative or occasional nuclei positive), 1+ (<10% of nuclei positive), 2+ (10–49% of nuclei positive), 3+ (50–74% of nuclei positive), or 4+ (≥75% of nuclei positive). On the whole tissue sections, positive staining was also classified as weak, moderate, or strong, and an immunohistochemical composite score, taking into account both extent and intensity of staining, was calculated. On whole tissue sections, there was a statistically significant difference between HMGA2 staining in serous and endometrioid carcinomas with regard to both extent and composite score, with higher expression in serous carcinomas (P < 0.0001). Thirty of 33 (91%) serous carcinomas were positive, usually with diffuse (3+ or 4+) staining. All five cases of serous endometrial intraepithelial carcinoma (EIC) (the postulated precursor of uterine serous carcinoma) were positive, as were 14 of 38 (37%) endometrioid carcinomas, usually with 1+ or 2+ staining. There was a statistically significant difference in HMGA2 staining in the TMAs between the serous and grade 3 endometrioid carcinomas, with higher expression in the former (P < 0.0001). Conclusions: Immunoreactivity for HMGA2 is diffusely positive in whole tissue sections in most uterine serous carcinomas and negative in most endometrioid carcinomas, although, as with other markers, there is overlap in individual cases. In conjunction with other markers, HMGA2 may be of value in problematic uterine carcinomas where the differential diagnosis includes serous and endometrioid carcinoma. As HMGA2 is expressed in serous EIC, this suggests that it may be implicated in the early development of uterine serous carcinoma.     

Oestrogen receptor gene (ESR1) amplification is frequent in endometrial carcinoma and its precursor lesions

Oestrogen receptor alpha (ER) plays a critical, diverse and not fully understood role in endometrial carcinoma. Most endometrial carcinomas express ER and some of these tumours respond favourably to anti-oestrogen therapy. On the other hand, tamoxifen therapy constitutes a major risk factor for endometrial carcinoma development. Amplification of the ESR1 gene encoding ER was recently shown to constitute a mechanism for ER over-expression in breast carcinoma. This study was designed to determine the potential role of ESR1 amplifications in endometrial carcinoma. Tissue microarrays of 368 endometrial carcinomas and large sections of 43 cases of endometrial hyperplasia were analysed for ESR1 gene amplification and ER protein expression by means of fluorescence in situ hybridization (FISH) and immunohistochemistry. FISH revealed ESR1 amplification in 40/176 (23%) cancers, 6/19 (32%) atypical complex hyperplasias, 3/10 (30%) complex hyperplasias without atypia and 2/14 (14%) simple hyperplasias without atypia. Strong ER protein expression was significantly linked to ESR1 amplification in endometrial carcinoma (p = 0.0036). These data indicate that ESR1 amplification might be one mechanism for ER over-expression in endometrial carcinoma, and suggest an early role for ESR1 amplification in the development of a significant fraction of endometrial carcinoma. Given the predictive role of ESR1 amplification for tamoxifen response in breast carcinoma, it will be interesting to investigate the response of ESR1-amplified endometrial cancers to anti-oestrogenic drugs. Copyright (c) 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Replicative MCM7 protein as a proliferation marker in endometrial carcinoma: a tissue microarray and clinicopathological analysis

AIMS: To assess, in tissue microarray (TMA), the proliferative activity of endometrial carcinoma using one of the minichromosome maintenance (MCM) proteins (MCM7), and to explore its potential value for prognosis. MCM proteins are essential for eukaryotic DNA replication and have recently been used to define the proliferative compartments in human tissues. METHODS AND RESULTS: Immunohistochemistry for MCM7 and Ki67 was performed on TMAs constructed from 212 cases of endometrial carcinoma. MCM7 and Ki67 expression was quantified according to the extent of nuclear staining. An analysis was carried out of the association between MCM7 expression and that of Ki67 and the clinicopathological characteristics of endometrial carcinoma. MCM7 and Ki67 immunoreactivity was clearly evident in the nuclei of tumour cells. MCM7 and Ki67 labelling indices in endometrial carcinomas correlated with each other (P < 0.001). A significant correlation existed between the MCM7 labelling index and histological grade (P = 0.008) and patients' age at diagnosis (P < 0.001). Well-differentiated carcinomas and younger patients had a lower MCM7 index. Poor survival was observed in patients with endometrial carcinoma with a high MCM7 index (P = 0.03) and MCM7 was found to be an independent prognostic factor by multivariate analysis (P = 0.04). The Ki67 labelling index correlated with histological grade (P = 0.01) but had no significant prognostic impact (P = 0.50). CONCLUSIONS: In this TMA study on endometrial carcinoma, MCM7 was found to be a more reliable and useful marker than Ki67 in assessing tumour proliferation and in the prognosis of patients.     

Use of mutation profiles to refine the classification of endometrial carcinomas

The classification of endometrial carcinomas is based on pathological assessment of tumour cell type; the different cell types (endometrioid, serous, carcinosarcoma, mixed, undifferentiated, and clear cell) are associated with distinct molecular alterations. This current classification system for high-grade subtypes, in particular the distinction between high-grade endometrioid (EEC-3) and serous carcinomas (ESC), is limited in its reproducibility and prognostic abilities. Therefore, a search for specific molecular classifiers to improve endometrial carcinoma subclassification is warranted. We performed target enrichment sequencing on 393 endometrial carcinomas from two large cohorts, sequencing exons from the following nine genes: ARID1A, PPP2R1A, PTEN, PIK3CA, KRAS, CTNNB1, TP53, BRAF, and PPP2R5C. Based on this gene panel, each endometrial carcinoma subtype shows a distinct mutation profile. EEC-3s have significantly different frequencies of PTEN and TP53 mutations when compared to low-grade endometrioid carcinomas. ESCs and EEC-3s are distinct subtypes with significantly different frequencies of mutations in PTEN, ARID1A, PPP2R1A, TP53, and CTNNB1. From the mutation profiles, we were able to identify subtype outliers, ie cases diagnosed morphologically as one subtype but with a mutation profile suggestive of a different subtype. Careful review of these diagnostically challenging cases suggested that the original morphological classification was incorrect in most instances. The molecular profile of carcinosarcomas suggests two distinct mutation profiles for these tumours: endometrioid-type (PTEN, PIK3CA, ARID1A, KRAS mutations) and serous-type (TP53 and PPP2R1A mutations). While this nine-gene panel does not allow for a purely molecularly based classification of endometrial carcinoma, it may prove useful as an adjunct to morphological classification and serve as an aid in the classification of problematic cases. If used in practice, it may lead to improved diagnostic reproducibility and may also serve to stratify patients for targeted therapeutics.     

Expression of multidrug resistance-associated protein in endometrial carcinomas: correlation with clinicopathology and prognosis

The objective of the study reported here was to investigate the expression of multidrug resistance-associated protein (MRP) in endometrial carcinomas and to evaluate the relationship between its expression and clinical data. Using immunohistochemistry, we examined MRP expression in 15 normal endometria, 10 cases of endometrial hyperplasia, and 64 cases of endometrial carcinoma. The normal endometrial glands were weakly immunopositive throughout the menstrual cycle. In addition, we found a progressive increase in the MRP expression of the endometrial hyperplasias. Of the 64 cases of endometrial carcinoma, 62 (97%) expressed MRP. Of these 62 cases, 34 (55%) showed strong immunostaining (>/=50%) and 28 (45%) showed weak immunostaining (<50%). In particular, the intensity of the immunostaining was very strong in 25 (71%) of the 35 grade 1 carcinomas. There was a significant difference in MRP expression between the grade 1 carcinomas and the more poorly differentiated carcinomas (grade 2 or grade 3) (P <.01), especially at stages 1a and 1b (P <.001). However, beyond stage 1c, there was no significant difference in MRP immunoreactivity between the histologic differentiations. Furthermore, beyond stage 1c, those patients with strongly MRP-positive carcinomas had a relatively poorer survival rate than those with weakly MRP-positive carcinomas (P <.05). We concluded that MRP immunoreactivity was already present in normal endometrium and showed a progressive increase from endometrial hyperplasia to well-differentiated carcinoma. Beyond stage 1c, strongly MRP-positive carcinoma indicated a poorer survival rate.     

Undifferentiated carcinoma of the endometrium: a review

Undifferentiated carcinoma of the endometrium is a high grade carcinoma and under-recognised, frequently diagnosed as grade 3 endometrioid carcinoma. We have found that undifferentiated carcinoma represents 9% of all endometrial carcinomas; it is composed of solid sheets of epithelial cells and in most cases only 5-10% of the cells are positive for keratin. The recognition of undifferentiated carcinoma is extremely important when this neoplasm is associated with a grade 1 or grade 2 endometrioid adenocarcinoma. In this situation it is important to diagnose the solid areas of carcinoma as undifferentiated and avoid evaluating them as the solid component of endometrioid carcinoma because there is significant difference between the excellent prognosis of grade 2 endometrioid carcinoma, the intermediate prognosis of grade 3 carcinoma, and the poor prognosis of undifferentiated carcinoma, which in cases of association with differentiated areas should be diagnosed as dedifferentiated endometrioid carcinoma.     

Loss of BAF250a (ARID1A) is frequent in high-grade endometrial carcinomas

Mutation of the ARID1A gene and loss of the corresponding protein BAF250a has recently been described as a frequent event in clear cell and endometrioid carcinomas of the ovary. To determine whether BAF250a loss is common in other malignancies, immunohistochemistry (IHC) for BAF250a was performed on tissue microarrays (TMAs) in more than 3000 cancers, including carcinomas of breast, lung, thyroid, endometrium, kidney, stomach, oral cavity, cervix, pancreas, colon and rectum, as well as endometrial stromal sarcomas, gastrointestinal stromal tumours, sex cord-stromal tumours and four major types of lymphoma (diffuse large B cell lymphoma, primary mediastinal B cell lymphoma, mantle cell lymphoma and follicular lymphoma). We found that BAF250a loss is frequent in endometrial carcinomas but infrequent in other types of malignancies, with loss observed in 29% (29/101) of grade 1 or 2 and 39% (44/113) of grade 3 endometrioid carcinomas of the endometrium, 18% (17/95) of uterine serous carcinomas and 26% (6/23) of uterine clear cell carcinomas. Since endometrial cancers showed BAF250a loss, we stained whole tissue sections for BAF250a expression in nine cases of atypical hyperplasia and 10 cases of atypical endometriosis. Of the nine cases of complex atypical endometrial hyperplasia, all showed BAF250a expression; however, of 10 cases of atypical endometriosis (the putative precursor lesion for ovarian clear cell and endometrioid carcinoma), one case showed loss of staining for BAF250a in the atypical areas, with retention of staining in areas of non-atypical endometriosis. This was the sole case that recurred as an endometrioid carcinoma, indicating that BAF250a loss may be an early event in carcinogenesis. Since BAF250a loss is seen in endometrial carcinomas at a rate similar to that seen in ovarian carcinomas of clear cell and endometrioid type, and is uncommon in other malignancies, we conclude that loss of BAF250a is a particular feature of carcinomas arising from endometrial glandular epithelium.     

Microsatellite instability is uncommon in uterine serous carcinoma.

Thirty-four uterine serous carcinomas, a type of endometrial carcinoma with aggressive behavior and a high frequency (90%) of p53 gene mutations, were analyzed for microsatellite instability (MI). Genomic DNA isolated from paired normal and tumor tissue was analyzed at eight microsatellite loci (D2S119, D2S123, D2S147, D10S197, D13S175, D18S58, D18S69, and ATn) located on four different chromosomes. All 34 tumors failed to meet the criteria for MI, defined as an alteration in the size of at least two of the microsatellite loci in tumor DNA when compared with normal DNA. Only three tumors demonstrated a shift in the size of a single microsatellite locus. Previously we reported MI in 20% of uterine endometrioid carcinomas, the most common type of endometrial carcinoma. The observed difference in the MI frequency between endometrioid and serous carcinoma is statistically significant (P = 0.003). Our data demonstrate that MI is uncommon in uterine serous carcinoma and support that different pathogenetic mechanisms are involved in the development of the two most common types of endometrial carcinoma.     

子宫内膜样腺癌中TBX2、PAX9的表达及其相关性

目的 探讨TBX2、PAX9在正常子宫内膜、子宫内膜增殖症和子宫内膜样腺癌(endometrioid adenocarcinoma,EA)组织中的表达及临床病理学意义.方法 采用组织芯片技术和免疫组化检测30例正常子宫内膜组织、30例单纯性增生内膜、30例复杂伴不典型性增生内膜、82例EA组织中TBX2、PAX9蛋白的表达.结果 TBX2蛋白在子宫内膜样腺癌中的阳性表达率明显高于正常子宫内膜和子宫内膜增殖症(P均＜0.01),TBX2过表达与组织学分级、临床分期、浸润程度均有相关性(P＜0.01,P＜0.05,P＜0.01),与淋巴结转移无相关性(P＞0.05);PAX9蛋白在子宫内膜样腺癌中的阳性表达率明显高于正常子宫内膜、子宫内膜单纯性增生(P均＜0.01),而和复杂伴不典型性增生之间没有统计学意义(P＞0.05),在复杂伴不典型增生中表达明显高于正常子宫内膜和单纯性增生内膜(P均＜0.01),PAX9阳性表达与组织学分级、临床分期、浸润程度均有相关性(P＜0.01,P＜0.01,P＜0.05),但与淋巴结转移无相关性(P＞0.05).TBX2与PAX9蛋白呈正相关(rs=0.427,P＜0.01).结论 TBX2和PAX9均在子宫内膜样腺癌中发生、发展中发挥重要作用,联合检测其表达可为子宫内膜样腺癌的早期诊断、预后判断提供有价值的指标.     

Atypical polypoid adenomyoma of the uterus: A reappraisal of the clinicopathological and immunohistochemical features

Atypical polypoid adenomyoma (APAM) is an uncommon uterine mixed epithelial and mesenchymal tumor. The discrimination from endometrial carcinoma remains to be clarified. In this study, we compared the clinicopathological and immunohistochemical features between 36 APAMs and 48 endometrial carcinomas. APAM with a highly complex structure (n?=?13) coexisted with atypical hyperplasia (n?=?5) and endometrial carcinoma (n?=?1). Two patients had endometrial carcinomas at 1 and 102 months. Four patients recurred at 1–57 months but none died of disease. The fibromuscular stroma demonstrated 3 uncharacterized features: a broad bundle (10/36), a lobular structure separated by the stromal branches (26/36), and the extension of fibromuscular stroma underneath the surface epithelium (31/36). However, these features were not seen in endometrial carcinomas except the vaguely lobular pattern. Both APAM and endometrial carcinoma showed a similar immunostaining pattern except high Ki67 index in endometrial carcinomas (p?<?0.05). Our study suggests that the distinct features of the fibromuscular stroma can aid in the differential diagnosis between APAM and endometrial carcinoma.     

Detection of testosterone and estrogen receptors in the postmenopausal endometrium

OBJECTIVE: To detect the presence of testosterone and estrogen receptors in the stroma and glandular epithelium in the malignant and non-malignant endometrium. METHODS: One hundred and forty-five consecutively-enrolled peri- or postmenopausal patients were submitted to diagnostic or operative hysteroscopy. These patients either had a history of abnormal uterine bleeding or they were asymptomatic with an endometrial echo greater than 4 mm. The presence of estrogen and testosterone receptors was determined in endometrial samples by immunohistochemistry, using monoclonal antibodies and a streptavidin-biotin peroxidase complex system with diamino benzidine as the chromogen. RESULTS: Testosterone receptors were detected mainly in the stroma in the non-malignant endometrial lesions and in the atypical glandular epithelium in cases of estrogen-positive endometrial carcinomas. CONCLUSIONS: The presence of testosterone receptors in estrogen receptor positive endometrial carcinomas may be involved in the mechanism of cell proliferation in these tumors. The strong staining reaction for testosterone receptors in the endometrial glands can be considered one of the features of invasive malignancy.     

DNA replication error in endometrial carcinoma and complex atypical endometrial hyperplasia.

We attempted to define the relation between DNA replication errors (RERs) in endometrial carcinomas and the precancerous lesion complex atypical endometrial hyperplasia (ATH) and clinicopathological characteristics. Tissue samples from 93 patients with endometrial carcinoma diagnosed as endometrioid adenocarcinoma and 26 patients with ATH (including 21 in whom endometrial carcinoma also was found) were prepared as formalin-fixed, paraffin-embedded sections. The samples were examined for the presence of RERs by the polymerase chain reaction with the use of five microsatellite markers. RERs were observed at > or = 1 loci in 32 endometrial carcinoma patients (34%); all 26 ATH patients were RER negative. RERs were observed in 25% of stage I and stage II cancer patients (16/64) and in 55% of stage III and stage IV cancer patients (16/29) (P = 0.009), as well as in 63% (10/16) of cancer patients with and in 27% (20/75) of patients without lymph-node metastases (P = 0.013). The incidence of RERs was not related to patient age, histological tumor grade, or prognosis. These results suggest that RER may be involved in the advanced rather than the early stages of endometrioid adenocarcinoma. There appears to be little association between RER and ATH.