Epithelial Membrane Antigen Immunostaining Research Articles

TdT expression in normal and neoplastic sebaceous cells.

Terminal deoxynucleotidyl transferase (TdT) is a DNA polymerase expressed in immature, normal and neoplastic, lymphoid or haematopoietic cells and in neuroendocrine carcinomas, such as Merkel cell carcinoma and small-cell carcinoma. It has not yet been described in cells of epithelial origin. After observing TdT immunoreactivity in normal sebaceous glands, we analysed its spectrum of expression in cases of sebaceous cell hyperplasia (SGH) and sebaceous cell neoplasm. Twelve cases of SGH and three cases of other benign lesions, namely sebaceoma, sebaceous adenoma, and sebaceous naevus, along with four archived cases of sebaceous cell carcinoma (SC) were collected and stained with TdT antibody. In addition, tissue microarrays were constructed from 11 cases of basal cell carcinoma (BCC) and 10 cases of squamous cell carcinoma (SCC), which had nine evaluable cases each, and, after carcinoma type confirmation with immunostaining for epithelial membrane antigen, TdT immunohistochemistry was performed. All cases of SGH and sebaceous cell neoplasm were positive for TdT. The staining intensity was variable, being often weak to moderate in a significant proportion of cells, apart from one case of SC and the case of sebaceous naevus, which were only focally positive. No BCCs and only one SCC showed immunoreactivity. TdT protein can be found in cells of epithelial origin and specifically sebaceous cells, both benign and malignant. It can be hypothesized that this expression is due to sebaceous cell differentiation as a prelude to apoptosis and holocrine secretion. Additional studies are needed to further elucidate its biological role.

Morphological, immunohistochemical, and chromosomal analysis of multicystic chromophobe renal cell carcinoma, an architecturally unusual challenging variant.

Chromophobe renal cell carcinoma (ChRCC) is typically composed of large leaf-like cells and smaller eosinophilic cells arranged in a solid-alveolar pattern. Eosinophilic, adenomatoid/pigmented, or neuroendocrine variants have also been described. We collected 10 cases of ChRCC with a distinct multicystic pattern out of 733 ChRCCs from our registry, and subsequently analyzed these by morphology, immunohistochemistry, and array comparative genomic hybridization. Of the 10 patients, 6 were males with an age range of 50-89years (mean 68, median 69). Tumor size ranged between 1.2 and 20cm (mean 5.32, median 3). Clinical follow-up was available for seven patients, ranging 1-19years (mean 7.2, median 2.5). No aggressive behavior was documented. We observed two growth patterns, which were similar in all tumors: (1) variable-sized cysts, resembling multilocular cystic neoplasm of low malignant potential and (2) compressed cystic and tubular pattern with slit-like spaces. Raisinoid nuclei were consistently present while necrosis was absent in all cases. Half of the cases showed eosinophilic/oncocytic cytology, deposits of pigment (lipochrome) and microcalcifications. The other half was composed of pale or mixed cell populations. Immunostains for epithelial membrane antigen (EMA), CK7, OSCAR, CD117, parvalbumin, MIA, and Pax 8 were positive in all tumors while negative for vimentin, TFE3, CANH 9, HMB45, cathepsin K, and AMACR. Ki67 immunostain was positive in up to 1% of neoplastic cells. Molecular genetic examination revealed multiple chromosomal losses in two fifths analyzable tumors, while three cases showed no chromosomal numerical aberrations. ChRCC are rarely arranged in a prominent multicystic pattern, which is probably an extreme form of the microcystic adenomatoid pigmented variant of ChRCC. The spectrum of tumors entering the differential diagnosis of ChRCC is quite different from that of conventional ChRCC. The immunophenotype of ChRCC is identical with that of conventional ChRCC. Chromosomal numerical aberration pattern was variable; no chromosomal numerical aberrations were found in three cases. All the cases in this series have shown an indolent and non-aggressive behavior.

Abstract P4-14-02: Neutralization of BCL2/BCL-XL enhances the cytotoxicity of T-DM1 in vivo

Abstract One of the most recent advances in the treatment of HER2+ breast cancer is the development of the antibody-drug conjugate, T-DM1, composed of trastuzumab (T) linked to the cytotoxic maytansinoid (DM1). T-DM1 has proven clinical benefits for patients with advanced and/or metastatic breast cancer who have progressed on prior HER2-targeted therapies. However, T-DM1 resistance ultimately occurs and represents a major obstacle in the effective treatment of this disease. We previously identified BCL2 upregulation as a critical component and biomarker of the adaptive response to inhibition of PI3K/mTOR or HER2, and thus examined whether BCL2/BCL-XL combinatorial strategies could improve the initial efficacy of T-DM1. Here, we demonstrate that combined inhibition of BCL2/BCL-XL proteins plus T-DM1 significantly enhances the cytotoxicity of T-DM1 in vivo. The effectiveness of T-DM1 plus BCL2/BCL-XL inhibition was evaluated in two patient-derived xenograft (PDX) models of advanced HER2+ER- resistant disease (PDX8 and PDX12). Animals were randomized into one of four treatment arms: T-DM1, ABT-737, T-DM1 + ABT-737 or vehicle controls. Our initial results after a 14d treatment period indicate that combined treatment with T-DM1 and ABT-737, the dual BCL2/BCL-XL inhibitor, confers an exceptional tumor cell cytotoxic advantage characterized by widespread elimination of the tumor cells. To evaluate whether ABT-263, the clinically relevant BCL2/BCL-XL inhibitor, mimics ABT-737, we randomized animals into one of four treatment arms: T-DM1 (administered weekly), ABT-263 (administered daily), T-DM1 + ABT-263 or vehicle controls. To minimize thrombocytopenia that is induced by ABT-263, we included a fifth treatment arm that received pulsed treatment of ABT-263 + T-DM1. Notably, unlike continuous treatment, pulsed administration of ABT-263 reduced weight loss to vehicle levels and allowed recovery of platelet counts. Evaluation of pathological responses by H&E staining indicated that T-DM1 + ABT-263 mimics T-DM1 + ABT-737. To better distinguish tumor cells from stromal elements, we used epithelial membrane antigen immunostaining to specifically visualize tumor cells and Trichrome stain to visualize stromal content and scored the tissue sections blindly. ABT-263 had no observable effect. T-DM1 induced a 38.75% and 20% average reduction in tumor cell content in the two PDX models, whereas the combined treatment caused a 74% and 54% average reduction after the 14d treatment period. The loss of tumor cell content was associated with an increased stromal reaction at the tumor bed. T-DM1 treated tumors contained 27.5% and 47.5% average stromal content, whereas combination treated tumors contained 86% and 85.6% average stromal content. Importantly, T-DM1 + pulsed ABT-263 treatment elicited a similar response as continuous treatment in the PDX8 model, but was not as effective in PDX12. The dramatic improvement in tumor regression observed in these preclinical studies, together with the safety benefits of modified dosing of ABT-263, provides substantial rationale for the clinical investigation of this combination therapy. Furthermore, thorough investigation of treatments that combine anti-apoptotic drugs with tumor-targeted chemotherapeutics could have broad implications in other cancer types. Citation Format: Zoeller JJ, Bronson RT, Sampath D, Leverson J, Brugge JS. Neutralization of BCL2/BCL-XL enhances the cytotoxicity of T-DM1 in vivo. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-14-02.

Utility of epithelial membrane antigen immunostaining in the differentiation between palmoplantar pustulosis and pompholyx

Utility of epithelial membrane antigen immunostaining in the differentiation between palmoplantar pustulosis and pompholyx

Abstracts and Case Studies From the College of American Pathologists 2012 Annual Meeting (CAP '12)

Abstracts and Case Studies From the College of American Pathologists 2012 Annual Meeting (CAP '12)

Mechanism of action of the Adiana ® device: a histologic perspective

Background The study was conducted to confirm the mechanism of action of the Adiana permanent contraception device by means of histologic analysis of long-term specimens. Study Design Fifteen specimens were obtained from eight subjects undergoing hysterectomy 2 to 4 years after the Adiana procedure. Serial sections were stained with hematoxylin and eosin, as well as epithelial membrane antigen immunostain. Results A normal foreign body reaction with minimal chronic inflammatory changes was observed in all specimens. Immunostaining for epithelial membrane antigen was absent in the interstitial tissue surrounding the matrix. Conclusion Histologic analysis of long-term specimens supports the mechanism of action of the Adiana permanent contraception device.

Invasive Ductal Carcinomas of the Breast Showing Partial Reversed Cell Polarity are Associated With Lymphatic Tumor Spread and may Represent Part of a Spectrum of Invasive Micropapillary Carcinoma

Invasive micropapillary carcinomas (IMPC) of the breast are aggressive tumors frequently associated with lymphatic invasion and nodal metastasis even when micropapillary (MP) differentiation is very focal within the tumors. We have noticed that some breast carcinomas showing lymphatic spread but lacking histologic features of IMPC have occasional tumor cell clusters reminiscent of those of IMPC without the characteristic prominent retraction artifact. To study the clinicopathologic significance of such features, we prospectively selected 1323 invasive ductal carcinomas and determined the presence and extent of MP differentiation and retraction artifact in the tumors. One representative tumor block per case was used for immunostaining for epithelial membrane antigen (EMA). Partial reverse cell polarity (PRCP) was defined as prominent linear EMA reactivity on at least part of the periphery of tumor cell clusters usually associated with decreased cytoplasmic staining. The clinicopathologic features of carcinomas with PRCP were compared with IMPC and invasive ductal (no special type) carcinomas without this feature. Of the 1323 cases, 96 (7.3%) and 92 (7.0%) showed MP features and the presence of PRCP, respectively. We found that the presence of both PRCP and MP features were strongly associated with decreased cytoplasmic EMA immunoreactivity and the presence of lymphatic invasion and nodal metastasis, even if such features were present only very focally. Our results suggest that breast carcinomas with PRCP may have the same implication as MP differentiation and these tumors may represent part of a spectrum of IMPC. Complete or partial reversal of cell polarity may play a significant role in lymphatic tumor spread.

Extraneural Sclerosing Perineurioma of the Buccal Mucosa: A Case Report and Clinicopathologic Review

The perineurioma is an infrequently encountered benign peripheral nerve sheath tumor composed of a clonal proliferation of perineurial cells. Rare cases of perineurioma have been reported in the oral cavity. An extraneural sclerosing perineurioma arising in the buccal mucosa of a 17-year-old male is presented. Histopathologically, the tumor is composed of a well circumscribed nodular proliferation of spindle cells arranged in a storiform growth pattern, in some areas subtly arranged around vascular channels. The tumor cells reveal positive immunostaining for epithelial membrane antigen (EMA), collagen type IV and vimentin, and negative immunostaining for S-100 protein, consistent with a perineurial origin. To the best of our knowledge, this case represents the first report of an extraneural sclerosing perineurioma involving the oral cavity.

A Case of Primary Synovial Sarcoma of the Thorax With a Variant SYT-SSX1 Fusion Transcript

With synovial sarcoma (SS) of the thorax, being exceptionally rare, its definite diagnosis is difficult, and the optimal therapy has not yet been established. An examination of our patient, a 64-year-old man with SS using a chest roentgenogram showed a large mass with homogeneous density in the lower two-thirds of the left hemithorax. A computed tomographic image of the chest revealed a large, heterogeneous, enhanced mass in the left hemithorax. Histologic examination of the resected tumor tissues suggested monophasic fibrous SS. A fragment of the SYT-SSX1 fusion transcript, which was smaller than the control, was amplified with reverse transcriptase polymerase chain reaction. Direct sequence analyses revealed the fusion between exon 9 of SYT and exon 5 of SSX1 instead of fusion between exon 10 of SYT and exon 6 of SSX1, which is found in most cases. Although the biological and clinical significance of this rare variant is not yet known, our data present another example of the usefulness of molecular analyses for making a definite diagnosis of SS in unusual sites.

Fibroblastic Polyp of the Colon and Colonic Perineurioma: 2 Names for a Single Entity?

Fibroblastic polyps of the colon and intestinal perineuriomas are unusual mucosal lesions with identical clinical and histologic features, and apparent different immunohistochemical and ultrastructural characteristics. However, immunohistochemical distinction was solely based on the results obtained with epithelial membrane antigen (EMA), an antibody whose reactivity on perineuriomas is difficult to demonstrate. Likewise, accurate ultrastructural diagnosis may be flawed by sampling error, preservation artifacts, or paucity of specific diagnostic features. In a recent short communication, it was suggested that both lesions may represent the same entity. To further evaluate this hypothesis, 28 colorectal polyps with clinical and histologic features of colonic fibroblastic polyps/perineuriomas (including 10 cases previously reported as fibroblastic polyps) were stained immunohistochemically for 4 markers of perineurial differentiation, that is, claudin-1, GLUT-1, collagen type IV, and EMA (the latter performed using an extended protocol for antigen retrieval and a kit for signal amplification). In addition, electron microscopy was performed in 4 cases. EMA and claudin-1 stained 26 of 28 (93%) polyps whereas GLUT-1 and collagen type IV were expressed in all of them. EMA reactivity was mostly focal and weak whereas the other markers displayed a diffuse and strong signal. Ultrastructural examination revealed elongated cells with features of perineurial differentiation including long, slender cytoplasmic processes with pinocytotic vesicles and an external lamina. Our findings support the hypothesis that fibroblastic polyps and perineuriomas of the colon represent the same entity. We suggest reclassifying fibroblastic polyps reactive to perineurial markers as perineuriomas. To reach an accurate diagnosis, we recommend employing at least 2 markers of perineurial differentiation, and performing EMA immunostaining with high antibody concentration, prolonged incubation time, and/or extended protocol for antigen retrieval.

CXCR4 and SDF1 expression in human meningiomas: A proliferative role in tumoral meningothelial cells in vitro1

Chemokines participate in cellular processes associated with tumor proliferation, migration, and angiogenesis. We previously demonstrated that stromal cell-derived factor 1 (SDF1) exerts a mitogenic activity in glioblastomas through the activation of its receptor CXCR4. Here we studied the expression of this chemokine in human meningiomas and its possible role in cell proliferation. Reverse transcriptase-PCR analysis for CXCR4 and SDF1 was performed on 55 human meningiomas (47 WHO grade I, 5 WHO II, and 3 WHO III). Immunolabeling for CXCR4 and SDF1 was performed on paraffin-embedded sections of these tumors. [(3)H]Thymidine uptake and Western blot analyses were performed on primary meningeal cell cultures of tumors to evaluate the proliferative activity of human SDF1alpha (hSDF1alpha) in vitro and the involvement of extracellular signal-regulated kinase 1/2 (ERK1/2) activation in this process. CXCR4 mRNA was expressed by 78% of the tumor specimens and SDF1 mRNA by 53%. CXCR4 and SDF1 were often detected in the same tumor tissues and colocalized with epithelial membrane antigen immunostaining. In 9 of 12 primary cultures from meningiomas, hSDF1alpha induced significant cell proliferation that was strongly reduced by the mitogen-activated protein kinase kinase inhibitor PD98059, involving ERK1/2 activation in the proliferative signal of hSDF1alpha. In fact, CXCR4 stimulation led to ERK1/2 phosphorylation/activation. In addition, the hSDF1alpha-induced cell proliferation was significantly correlated with the MIB1 staining index in the corresponding surgical specimen. In conclusion, we found that human meningiomas express CXCR4 and SDF1 and that hSDF1alpha induces proliferation in primary meningioma cell cultures through the activation of ERK1/2.

Low grade malignant peripheral nerve sheath tumor with smooth muscle differentiation

Malignant peripheral nerve sheath tumors are usually Schwann cell derived. Differentiation along mesenchymal lines is uncommon. Herein we present an example with smooth muscle differentiation occurring in the left distal forearm of a 62-year-old male with neurofibromatosis type I. Incisional biopsy of the slowly growing mass demonstrated a low-grade malignant peripheral nerve sheath tumor with strong S-100 protein immunoexpression as well as focal smooth muscle actin staining in atypical neoplastic cells. Immunostains for epithelial membrane antigen, neurofilament protein, glial fibrillary acidic protein, CD57, desmin, and myogenin were negative. The MIB-1 labeling index was 5.4%. Electron microscopy revealed arrays of microfilaments (actin myofilaments) variably associated with fusiform dense bodies, plasmalemmal micropinocytotic vesicles, and foci of external lamina (basement membrane) consistent with smooth muscle differentiation. Smooth muscle should be added to the spectrum of differentiation exhibited by malignant peripheral nerve sheath tumors. Its recognition requires exclusion of the alternative diagnosis of leiomyosarcoma.

Pigmented malignant hidroacanthoma simplex mimicking irritated seborrheic keratosis

Pigmented variant of malignant hidroacanthoma simplex (PMHS) is very rare. We are aware of only two reported cases, all arising in pigmented hidroacanthoma simplex (HS). We report the third case of PMHS arising in a pigmented HS. A 71-year-old-woman presented with a well-demarcated pigmented hyperkeratotic tumor on the right knee resembling irritated seborrheic keratosis. Histopathologic examination of the excised tumor revealed intraepidermal proliferation of atypical polygonal poroid cells forming large, sharply demarcated nests with colonization of dendritic melanocytes. In addition, there were focal changes of a benign pigmented HS and syringofibroadenoma. The key diagnostic features of ductal structures and intracytoplasmic lumina were highlighted by carcinoembryonic antigen and epithelial membrane antigen immunostaining. PMHS should be differentiated from irritated seborrheic keratosis, melanoacanthoma, Bowen's disease and malignant melanoma both clinically and pathologically.

Usefulness of epithelial membrane antigen (EMA) to discriminate between perineural invasion and perineural indentation in prostatic carcinoma

Perineural invasion (PNI) is one of the few unequivocal criteria to diagnose adenocarcinoma of the prostate. Distinguishing PNI from perineural indentation (PNIn), however, is sometimes difficult. The aim of this study was to discriminate between PNI and PNIn using EMA immunohistochemistry. We selected representative sections from 87 prostatectomies with prostatic adenocarcinoma. Normal peripheral nerves were continuously encircled with perineurium, which was immunoreactive for EMA. We identified 1319 PNI by carcinomas, 368 PNIn by carcinomas, and 303 PNIn by benign glands. We categorized the EMA immunoreactivity patterns into three classes: samples that displayed discontinuity or complete loss of the perineurium (Type A), samples where there were carcinomas or benign glands in the perineural space or peripheral nerves (Type B) and samples that showed no changes in the perineurium (Type C). For PNI we observed Type A, Type B, and Type C patterns in 55.3%, 24.8% and 19.9% of carcinomas, respectively. The incidence of each of those patterns in PNIn by carcinomas was 32.1%, 14.9% and 53.0%, respectively. Cases of PNIn by benign glands showed Type A or Type C patterns. They did not, however, exhibit Type B patterns. EMA immunostaining will aid the diagnosis of prostatic adenocarcinoma.

Intestinal Perineuriomas

Benign peripheral nerve sheath tumors are uncommon in the gastrointestinal tract, and perineuriomas have not previously been reported to occur at this anatomic location. In this study, we analyzed the clinicopathologic and immunohistochemical features of 10 perineuriomas arising in the intestine. Eight patients were female and 2 male (median age, 51 years; range, 35-72 years). Eight of the lesions were intramucosal perineuriomas presenting as small sessile polyps detected during colonoscopy; 6 of these 8 patients were asymptomatic and undergoing colorectal cancer screening. The remaining 2 cases were submucosal masses, one each located in the colon and jejunum. Of the mucosal polyps, six were located in the rectosigmoid or sigmoid colon and one each was detected in the descending colon and transverse colon. The polyps ranged from 0.2 to 0.6 cm (median, 0.4 cm) in greatest dimension. The colonic and jejunal masses measured 3 cm and 4.5 cm, respectively. Histologically, the intramucosal perineuriomas were composed of uniform bland spindle cells having ovoid to elongated nuclei and pale indistinct cytoplasm, with no cytologic atypia, pleomorphism, or mitotic activity. The lesions had a fine collagenous stroma, demonstrated irregular borders with the adjacent lamina propria, and entrapped colonic crypts. Five cases exhibited hyperplastic changes in the adjacent or entrapped epithelium. The colonic submucosal tumor was microscopically well circumscribed, whereas the jejunal perineurioma showed focal infiltration through the muscularis propria into the subserosa. The stroma was collagenous in the colonic tumor and predominantly myxoid in the jejunal tumor. The spindle cells in the submucosal perineuriomas demonstrated tapered nuclei and elongated bipolar cytoplasmic processes. All tumors except one were positive for epithelial membrane antigen (EMA); 4 of 10 expressed claudin-1 and 2 of 10 expressed CD34. All tumors were negative for S-100 protein, glial fibrillary acidic protein, neurofilament protein, smooth muscle actin, desmin, caldesmon, KIT, and pan-keratin. Electron microscopy was performed on the tumor lacking EMA expression, revealing typical features of perineurioma, namely, spindle cells with long bipolar cytoplasmic processes and prominent pinocytotic vesicles, surrounded by discontinuous basal lamina. Clinical follow-up was available for 4 patients (median, 34 months; range, 8-53 months). No tumor recurred. In summary, perineuriomas may arise in the intestine, most often as intramucosal lesions detected as colorectal polyps with distinctive histologic features including entrapment of colonic crypts. Distinguishing perineuriomas from other spindle cell neoplasms of the gastrointestinal tract can be facilitated by immunostaining for EMA and claudin-1.

Light microscopic demonstration of the microlumen of ependymoma: A study of the usefulness of antigen retrieval for epithelial membrane antigen (EMA) immunostaining

To determine the origin of dotlike epithelial membrane antigen (EMA) immunoreactivity of ependymoma, which is consistent with the eosinophilic globular body in hematoxylin and eosin (H&E) stain, an immunoelectron microscopic study was undertaken. The usefulness of antigen retrieval pretreatment in detecting the dotlike EMA immunoreactivity in ependymomas was also studied. The materials were 29 ependymomas, 7 autopsy brains as a normal control, and 50 brain tumors of various types. The study confirmed that most of the brown dots in EMA immunostain in ependymoma represented microlumina of tumor cells. In ependymomas, plain EMA immunostaining showed dotlike positivity in only six cases (21%), and antigen retrieval pretreatment increased the number of positives up to 26 cases (90%). Antigen retrieved CD99 detected 23 positive cases (80%) in ependymomas. On the basis of the results, although some false positive findings were raised by antigen retrieval pretreatment, the authors positively recommend adoption of the technique, especially when ependymoma remains as one of the differential diagnoses of the tumor.

Detection of occult cervical micrometastases in patients with head and neck squamous cell cancer.

The incidence of occult nodal metastases associated with head and neck squamous cell carcinoma (HNSCC) and the clinical significance of nodal micrometastases by cytokeratin immunohistochemical analysis are examined. In all, 1012 lymph nodes from 50 patients treated between 1992 and 2001 at the University of Colorado Health Sciences Center (Denver, CO) were evaluated retrospectively for micrometastases. Serial sectioning in 5-to 6-microm interval specimens stained either with hematoxylin and eosin (H&E) or immunostaining for cytokeratins using the monoclonal antibody cocktail AE1/AE3 was performed in 21 N0, 11 N1, and 14 N2 patient cases. Cases that showed scattered cells with suspect staining qualities but without morphological features consistent with HNSCC were further evaluated by epithelial membrane antigen (EMA) immunohistochemical analysis. H&E-stained and cytokeratin-stained sections revealed occult nodal micrometastases in 3.8% of N0 and 5% of N1 cases. Overall, 26 micrometastases were identified in N0 and N1 patients, causing 29% of N0 patients and 45% of N1 patients to be upstaged. Cytokeratin immunostaining detected micrometastases in eight cases that were negative on H&E serial sectioning. Serial sectioning by H&E alone identified three additional micrometastases. Negative EMA immunostaining confirmed the absence of malignant cells in lymph node sections that were equivocal on cytokeratin staining. The use of serial sectioning with H&E and cytokeratin immunohistochemical analysis increases the detection of micrometastases that are often elusive by routine processing in patients with HNSCC. Improved methods of detecting micrometastases may provide a basis for improved planning of postoperative therapy for patients already at risk for tumor recurrence.

A Comparison of Epithelial Membrane Antigen Overexpression in Benign and Malignant Endometrium

Objective. The aim of this study was to analyze the value of epithelial membrane antigen (EMA) overexpression in benign and malignant endometrium and its prognostic significance.Methods. EMA immunostaining was performed in 178 paraffin-embedded specimens including 105 endometrial cancers, 40 endometrial hyperplasias, and 33 benign endometriums. EMA immunostaining was correlated with traditional prognostic factors and progression-free survival in endometrial cancer specimens.Results. EMA overexpression was observed more frequently in adenocarcinomas (60%) than in hyperplasias (15%) or benign endometrium (9.1%). EMA overexpression was observed in two patients with endometrial hyperplasia who progressed to carcinoma. In adenocarcinomas, EMA overexpression had a positive correlation with nonendometrioid subtypes (P = 0.012). In multivariate analysis, FIGO stage (P = 0.025) and EMA overexpression (P = 0.017) were independent prognostic factors for progression-free survival.Conclusions. EMA overexpression appears to be a marker of malignant transformation in the endometrium and it is an independent predictor of recurrent disease in endometrial cancer.

Lymphoepithelioma-like salivary gland carcinoma in Taiwan: a clinicopathological study of nine cases demonstrating a strong association with Epstein-Barr virus.

Lymphoepithelioma-like carcinoma (LELC) of the salivary glands is a rather rare tumour. Previous studies have shown its strong association with Epstein-Barr virus (EBV) among Chinese and Eskimos. We tested this observation with nine Chinese patients with salivary gland LELC in Taiwan including one with coexisting nasopharyngeal carcinoma (NPC) and studied the prognostic significance of their histopathological features. This series showed a predilection for female patients and parotid glands with a median age of 50 years. Three patients died 18.5-26 months after the diagnosis including the case with NPC. Six patients were alive without recurrence for 14-45 months with a median follow-up of 34.5 months. Histopathologically, the tumours showed either lobular or diffuse growth pattern. Granulomas and/or germinal centres were observed in most cases and both B- and T-cells were found in the lymphoid infiltrates, indicating that the salivary gland LELC was capable of inducing a strong host immune reaction. Microscopic growth pattern, lymph node metastasis, and presence or absence of granulomas and/or germinal centres seemed to be important prognostic factors. Both salivary gland LELC and NPC shared similar histopathological appearance and positive immunostaining for epithelial membrane antigen and cytokeratin AE1 but not AE3. Granulomas and amyloid might occur in both tumours. A nasopharyngeal examination is indicated in patients with salivary gland LELC to exclude the possibility of coexisting or metastatic NPC. All nine cases showed positive nuclear signals for EBV-encoded RNA by in situ hybridization including the case with NPC. Our study and the previously published studies show that the association of salivary gland LELC and EBV is strongly related to racial and geographical factors.

Lymphocyte Predominance Hodgkin’s Disease: Lineage and Clonality Determination Using a Single-Cell Assay

Lymphocyte predominance Hodgkin's disease (LPHD) is a clinically indolent condition. Although there is evidence that the putative neoplastic cell in this disease, the "L&H" cell, is of B-cell lineage, there is conflicting data concerning the clonality of these cells. Our study was aimed at clarifying the issue of lineage and clonality of the L&H cells of LPHD using a single-cell assay. Four cases of LPHD were studied. To circumvent the difficulties of obtaining fresh tissue and to be able to study representative cases, a new method was developed to obtain single-cell suspensions of L&H cells from archival formalin-fixed paraffin-embedded tissue. Single L&H cells were identified by morphology and immunostaining for epithelial membrane antigen, isolated using a micropipette, and subjected to polymerase chain reaction (PCR) amplification of the complematarity determining region 3 (CDR3) of the Ig heavy chain (IgH) gene, which is B-cell clone-specific. The PCR products were size-fractionated by polyacrylamide gel electrophoresis and representative products were directly sequenced. Single T cells and small B cells were also isolated from the tissues and used as negative and positive controls, respectively. In all four cases of LPHD, the IgH CDR3 of single L&H cells could be amplified. Within each case, the IgH CDR3 of single L&H cells was found to be of different length or of different sequence. Therefore, our results provide strong evidence for the B-cell origin of the L&H cells and the polyclonal nature of LPHD.