Membrane Antigen (membrane + antigen)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Membrane Antigen

  • epithelial membrane antigen
  • prostate-specific membrane antigen


  • Selected Abstracts


    An HPLC/mass spectrometry platform for the development of multimodality contrast agents and targeted therapeutics: prostate-specific membrane antigen small molecule derivatives

    CONTRAST MEDIA & MOLECULAR IMAGING, Issue 5 2006
    Valerie Humblet
    Abstract The production of disease-targeted agents requires the covalent conjugation of a targeting molecule with a contrast agent or therapeutic, followed by purification of the product to homogeneity. Typical targeting molecules, such as small molecules and peptides, often have high charge-to-mass ratios and/or hydrophobicity. Contrast agents and therapeutics themselves are also diverse, and include lanthanide chelates for MRI, 99mTc chelates for SPECT, 90Y chelates for radiotherapy, 18F derivatives for PET, and heptamethine indocyanines for near-infrared fluorescent optical imaging. We have constructed a general-purpose HPLC/mass spectrometry platform capable of purifying virtually any targeted agent for any modality. The analytical sub-system is composed of a single dual-head pump that directs mobile phase to either a hot cell for the purification of radioactive agents or to an ES-TOF MS for the purification of nonradioactive agents. Nonradioactive agents are also monitored during purification by ELSD, absorbance and fluorescence. The preparative sub-system is composed of columns and procedures that permit rapid scaling from the analytical system. To demonstrate the platform's utility, we describe the preparation of five small molecule derivatives specific for prostate-specific membrane antigen (PSMA): a gadolinium derivative for MRI, indium, rhenium and technetium derivatives for SPECT, and an yttrium derivative for radiotherapy. All five compounds are derived from a highly anionic targeting ligand engineered to have a single nucleophile for N -hydroxysuccinimide-based conjugation. We also describe optimized column/mobile phase combinations and mass spectrometry settings for each class of agent, and discuss strategies for purifying molecules with extreme charge and/or hydrophobicity. Taken together, our study should expedite the development of disease-targeted, multimodality diagnostic and therapeutic agents. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Pulmonary non-Hodgkin's lymphoma (NHL) of diffuse large B-cell type with simultaneous humeral involvement in a young lady: An uncommon presentation with cytologic implications

    DIAGNOSTIC CYTOPATHOLOGY, Issue 3 2010
    C.T., Irene Ruben B.Sc.
    Abstract A bronchogenic carcinoma, almost invariably, presents as a lung mass. Primary pulmonary lymphomas are rare. We report an unusual case of a pulmonary non-Hodgkin's lymphoma (NHL) with simultaneous involvement of the right humerus in a 37 year old lady. Bronchial lavage smears showed atypical cells with irregular nuclear membranes raising a suspicion of a hematolymphoid tumor, over a small cell carcinoma that was the closest differential diagnosis. Biopsy from the lung mass and from the lesion in the humerus showed an identical malignant round cell tumor with prominent apoptosis. On immunohistochemistry (IHC), tumor cells were diffusely positive for leukocyte common antigen (LCA), CD20 and MIB1 (70%), while negative for cytokeratin (CK), epithelial membrane antigen (EMA) synaptophysin, chromogranin, neuron specific enolase (NSE), CD3, and CD10. Diagnosis of a pulmonary NHL of diffuse large B-cell type with involvement of the humerus was formed. The case is presented to create an index of suspicion for the possibility of a NHL on respiratory samples, while dealing with small round cells with irregular nuclear membranes. IHC is necessary to confirm he diagnosis. A simultaneous association in the humerus in our case makes it unusual. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source]


    Desmoplastic round cell tumor of childhood: Can cytology with immunocytochemistry serve as an alternative for tissue diagnosis?

    DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2005
    Dr Brijal Dave M.D.
    Abstract There are limited reports on the cytology of desmoplastic small round cell tumors (DSRCT). Fine needle aspiration biopsy (FNAB) findings in seven aspirates from four cases of histologically and immunohistochemically confirmed cases were analyzed with the main intention of ascertaining if cytological diagnosis of DSRCT is possible. Also assessed were the immunocytochemistry(ICC) findings in these cases. The basic cytological impression was that of a cohesive small round cell tumor. Nuclei showed granular chromatin with grooves, nuclear molding and inconspicuous nucleoli. Stromal fragments were noted in all four cases. In two cases, awareness of cytological features in the appropriate clinical context led to a suggestion of the diagnosis of DSRCT on cytology itself. ICC on destained smears showed positivity for cytokeratin, epithelial membrane antigen (EMA), desmin and WT-1 in two cases. In conclusion, given the right clinical setting, a cytological diagnosis of DSRCT is plausible and in conjunction with ICC may help in documenting the polyphenotypic nature and thereby confirming the diagnosis. Diagn. Cytopathol. 2005;32:330,335. © 2005 Wiley-Liss, Inc. [source]


    Role of immunocytochemistry and DNA flow cytometry in the fine-needle aspiration diagnosis of malignant small round-cell tumors

    DIAGNOSTIC CYTOPATHOLOGY, Issue 4 2001
    Urmil Brahmi M.Sc.
    Abstract In the present study, DNA flow cytometry (FCM) and immunocytochemistry (ICC) with a selected panel of antibodies were performed on 51 cases of malignant tumors which were referred for fine-needle aspiration biopsy (FNAB) to our Department of Cytology for the last 2 yr. Twelve cases were diagnosed as neuroblastoma, 16 as Ewing's sarcoma, 2 as retinoblastoma, 5 as non-Hodgkin's lymphoma (NHL), 5 as rhabdomyosarcoma, 2 as peripheral neuroectodermal tumors (PNETs), and 8 as Wilms' tumor. Eleven of 12 neuroblastomas were diploid by FCM, and 1 was aneuploid, with an S-phase fraction (SPF) of 8.3%. Neuron-specific enolase (NSE) was negative in 3 and positive in 8 cases of neuroblastoma, whereas neuroblastoma marker was positive in 3/11. Sixteen of 17 Ewing's sarcomas were diploid, and 1 showed tetraploid aneuploidy, with an SPF of 10.06%. Eight of 13 Ewing's sarcomas were positive for Mic-2 gene product (Ewing's marker). All 5 NHL were positive for leukocyte-common antigen (LCA). Three of 5 rhabdomyosarcomas were diploid, and 2 cases showed aneuploidy. Rhabdomyosarcoma showed muscle-specific actin positivity in 4 and desmin positivity in 3 cases. All 3 cases of PNET were diploid and positive for the Mic-2 gene product, whereas NSE and vimentin were positive in 2 cases. Both cases of retinoblastoma were diploid. Immunostaining was noncontributory in 1 case, and the other showed positivity for the retinoblastoma gene product, NSE, and chromogranin. Seven of 8 Wilms' tumors were diploid, and 1 showed aneuploid, with an SPF of 11.13%. Seven of 8 Wilms' tumors were positive for cytokeratin (CK), 5 were positive for NSE, 6 were positive for epithelial membrane antigen (EMA), and 5 were positive for vimentin. FNAB diagnosis of malignant round-cell tumors is difficult only by light microscopy. Due to the availability of specific markers for subgrouping tumors, ICC has proved to be more useful these days, while DNA FCM has little diagnostic value, as most of them are diploid. Further ancillary studies, e.g., electron microscopy, image analysis, and other molecular investigations, are required to further categorize these tumors more precisely for better clinical management of these cases. Diagn. Cytopathol. 24:233,239, 2001. © 2001 Wiley-Liss, Inc. [source]


    Highly efficient capture and enumeration of low abundance prostate cancer cells using prostate-specific membrane antigen aptamers immobilized to a polymeric microfluidic device

    ELECTROPHORESIS, Issue 18 2009
    Udara Dharmasiri
    Abstract Prostate tumor cells over-express a prostate-specific membrane antigen (PSMA) that can be used as a marker to select these cells from highly heterogeneous clinical samples, even when found in low abundance. Antibodies and aptamers have been developed that specifically bind to PSMA. In this study, anti-PSMA aptamers were immobilized onto the surface of a capture bed poised within a PMMA, microchip, which was fabricated into a high-throughput micro-sampling unit (HTMSU) used for the selective isolation of rare circulating prostate tumor cells resident in a peripheral blood matrix. The HTMSU capture bed consisted of 51 ultra-high-aspect ratio parallel curvilinear channels with a width similar to the prostate cancer cell dimensions. The surface density of the PSMA-specific aptamers on an ultraviolet-modified PMMA microfluidic capture bed surface was determined to be 8.4×1012,molecules/cm2. Using a linear velocity for optimal cell capture in the aptamer-tethered HTMSU (2.5,mm/s), a recovery of 90% of LNCaP cells (prostate cancer cell line; used as a model in this example) was found. Due to the low abundance of these cells, the input volume required was 1,mL and this could be processed in ,29,min using an optimized linear flow rate of 2.5,mm/s. Captured cells were subsequently released intact from the affinity surface using 0.25%,w/w trypsin followed by counting individual cells using a contact conductivity sensor integrated into the HTMSU that provided high detection and sampling efficiency (,100%) and did not require staining of the cells for enumeration. [source]


    ERG rearrangement in small cell prostatic and lung cancer

    HISTOPATHOLOGY, Issue 7 2010
    Veit J Scheble
    Scheble V J, Braun M, Wilbertz T, Stiedl A-C, Petersen K, Schilling D, Reischl M, Seitz G, Fend F, Kristiansen G & Perner S (2010) Histopathology,56, 937,943 ERG rearrangement in small cell prostatic and lung cancer Aims:, Small cell prostatic cancer is a rare but aggressive disease. Currently, its histogenetic origin is unclear and its distinction from metastatic small cell lung cancer is challenging. The aim of our study was to determine whether the ERG rearrangement commonly observed in acinar prostatic cancer can distinguish small cell prostatic cancer from small cell lung cancer samples. Methods and results:, We assessed 15 small cell prostatic cancers and 22 small cell lung cancers for ERG rearrangement using fluorescence in situ hybridization. Commonly used and novel immunohistochemical markers (i.e. androgen receptor, calcium activated nucleotidase 1, Golgi phosphoprotein 2, prostate-specific antigen, prostate-specific membrane antigen, CD56, epithelial membrane antigen, thyroid transcription factor 1, chromogranin A, synaptophysin and Ki67) were further studied. ERG rearrangement occured in 86% of small cell prostatic cancers but in none of the small cell lung cancers and was the best marker to differentiate between both tumours (P < 0.0001). Conclusions:, The ERG rearrangement is commonly observed in small cell prostatic cancer, supporting the hypothesis that ERG rearrangement occurs in aggressive prostatic cancers. Furthermore, the ERG rearrangement is the most significant marker to differentiate between small cell prostatic cancer and small cell lung cancer. Moreover, our data suggest that small cell prostatic cancer is not a tumour entity on its own, but a dedifferentiated variant of common acinar prostatic cancer. [source]


    Sensitivity and specificity of immunohistochemical antibodies used to distinguish between benign and malignant pleural disease: a systematic review of published reports

    HISTOPATHOLOGY, Issue 6 2006
    J King
    Aims:, A systematic review of published reports that have evaluated the ability of immunohistochemistry and argyrophil nucleolar organizing region (AgNOR) staining to distinguish between benign and malignant pleural disease. Methods:, Nineteen relevant papers published during the period 1979,2005 were identified. Individual results of immunohistochemistry for five diagnostic antibodies were extracted to calculate diagnostic sensitivity and specificity. Results from five of these studies that had evaluated proliferation markers or AgNOR staining techniques were also summarized. Results:, Most antibodies demonstrated poor to moderate diagnostic ability. Desmin and epithelial membrane antigen (EMA) were the most useful, with sensitivity and specificity both above 74%. The combination of EMA and AgNOR was reported as having 95% diagnostic sensitivity. A high MCM2 labelling index also differentiated between benign and malignant pleural disease. Conclusions:, Immunohistochemistry is of limited value, but newer diagnostic methods may be useful additions in this area of pathology. The diagnostic importance of histological features seen on plain tissue sections is emphasized as vital for correctly differentiating between benign pleural disease and malignant pleural mesothelioma. [source]


    The diagnostic utility of MOC31, BerEP4, RCC marker and CD10 in the classification of renal cell carcinoma and renal oncocytoma: an immunohistochemical analysis of 328 cases

    HISTOPATHOLOGY, Issue 5 2004
    C-C Pan
    Aims:, To demonstrate the diagnostic utility of MOC31, BerEP4, renal cell carcinoma marker (RCC Ma) and CD10 in the classification of RCC and renal oncocytoma, based upon a comprehensive immunohistochemical analysis. Methods and results:, Immunohistochemistry was performed on 328 samples consisting of 256 clear cell/conventional, 27 papillary, 28 chromophobe, five collecting duct, five unclassified RCCs and seven renal oncocytomas using antibodies MOC31, BerEP4 and antibodies against cytokeratins (KL-1, CAM5.2, 34,E12, cytokeratin 7), RCC Ma, epithelial membrane antigen, E-cadherin, CD10, CD15 and vimentin. Multivariate analysis showed that MOC31, BerEP4, RCC Ma and CD10 have discriminatory value. MOC31 and BerEP4 chiefly labelled distal tubules of normal kidney while RCC Ma and CD10 labelled the proximal tubules. Twenty-three chromophobe RCCs (82%) were reactive for MOC31, while only four clear cell RCCs and three papillary RCCs were positive for this marker. Clear cell RCCs were characterized by a high positive rate for CD10 (82%) and a low positive rate for BerEP4 (27%). Papillary RCCs frequently coexpressed RCC Ma and BerEP4 (51%). All renal oncocytomas were negative for MOC31 and CD10. Conclusions:, MOC31 has diagnostic merit in discerning chromophobe RCC. The CD10+/BerEP4, profile and RCC Ma+/BerEP4+ profile achieve moderate sensitivity and good specificity for clear cell RCC and papillary RCC, respectively. The non-reactivity for both MOC31 and CD10 is helpful in distinguishing renal oncocytoma from RCC. When properly selected, antibodies have immunohistochemical diagnostic utility for the classification of renal cortical epithelial tumours. [source]


    Cutaneous sclerosing perineurioma of the digit

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 9 2006
    Toshitsugu Nakamura MD
    An 11-year-old Japanese girl noticed a small nodule, with mild tenderness, on the right index finger 5 years before visiting our outpatient clinic. She had no familial history of neurofibromatosis or past history of traumatic injury at the site of the tumor. Physical examination revealed a slightly elevated, subcutaneous, nodular tumor in the volar aspect between the proximal and distal interphalangeal joints of the digit (Fig. 1A). By magnetic resonance imaging examination, the tumor showed low density on both T1- and T2-weighted images, and was located just adjacent to the tendon with no invasive signs. The tumor was extirpated; at operation, it was well circumscribed and mobile without adhesion to adjacent tendon or nerve, and was easily removed. Figure 1. (a) Slightly elevated subcutaneous tumor (arrow) on the volar aspect of the right index finger. (b) gross appearance of the extirpated tumor, showing a well-circumscribed, whitish solid nodule Grossly, the tumor was a well-circumscribed, firm nodule (10 mm × 8 mm × 5 mm in size) (Fig. 1B). The cut surface was whitish, homogeneous, and solid without cystic lesions. Histologically, it was an unencapsulated, paucicellular dense, fibrous nodule with a concentric circular arrangement of collagen bundles (Fig. 2A). Amongst the fibrous bundles, a small number of ovoid/epithelioid or plump spindle cells were arranged in a corded, trabecular, or whorled (onion bulb-like) pattern (Fig. 2B); a storiform pattern was not noted. These cells were relatively uniform and had a somewhat elongated, slightly hyperchromatic nucleus with fine granular chromatin. Neither nuclear pleomorphism nor multinucleated cells were evident, and necrosis and mitotic figures were not observed. Periodic acid,Schiff (PAS) stain after diastase digestion highlighted the corded or whorled pattern of the tumor cells by encasing them. For immunohistochemical examination, formalin-fixed, paraffin-embedded serial tissue sections were stained by a labeled streptavidin,biotin method. The tumor cells were positive for vimentin and epithelial membrane antigen (EMA) (Fig. 3A), and negative for pan-cytokeratin, carcinoembryonic antigen (CEA), CD34, ,-smooth muscle actin, desmin, and CD68. Type IV collagen and laminin (Fig. 3B) were detected along the cords or whorls of the tumor cells, similar to the staining pattern of the diastase-PAS reaction. Schwann cells and axonal components, immunoreactive for S100 protein and neurofilament, respectively, were focally detected just adjacent to the cords or whorls, although the tumor cells per se did not express these proteins. Consequently, the tumor was found to be perineurial in origin and was diagnosed as cutaneous sclerosing perineurioma. Figure 2. (a) Low-power view of the tumor, showing an unencapsulated, paucicellular, dense, fibrous nodule with a concentric circular arrangement of collagen bundles (hematoxylin and eosin stain: original magnification, ×15). (b) Higher magnification of the tumor, showing ovoid or epithelioid cells arranged in cords or whorls in the abundant collagen bundles (hematoxylin and eosin stain: original magnification, ×150) Figure 3. Immunohistochemical profiles of the tumor. The tumor cells are positive for epithelial membrane antigen (a) and are surrounded by laminin (b) (original magnification, ×150) [source]


    Acral lentiginous melanoma: an immunohistochemical study of 20 cases

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2003
    You Chan Kim MD
    Background Though acral lentiginous melanoma (ALM) is a major type of malignant melanoma, no immunohistochemical study on this type of melanoma has been reported. Objective The purpose of this study is to analysis the immunohistochemical findings of ALM using routinely used immune markers. Methods An immunohistochemical study was performed on paraffin sections of 20 ALMs using S-100 protein, HMB-45, MART-1, vimentin, epithelial membrane antigen (EMA) and CAM 5.2. Results S-100 protein (95%) was found to be a more sensitive marker than either HMB-45 (80%) or MART-1 (70%) for recognizing ALM. Melanin bleaching was useful for recognizing heavily pigmented ALM using both S-100 protein and HMB-45. The intensity of HMB-45 correlated well with the melanin content. However, there was no significant correlation between the intensity of S-100 protein and the melanin content. One and two out of 20 cases stained focally with EMA and CAM5.2, respectively, but these cases stained also with HMB-45 and/or S-100 protein. Conclusions S-100 protein and HMB-45 were relatively sensitive markers for recognizing ALM. Despite the occasional positivity for the epithelial markers in ALM, all epithelial marker-positive cases stained also with HMB-45 and/or S-100 protein. Therefore, we recommend that the panel of antibodies used for recognizing ALM should contain at least S-100 protein and HMB-45. [source]


    A clonal cutaneous CD30+ lymphoproliferative eruption in a patient with evidence of past exposure to hepatitis E

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2000
    Freddye M. Lemons-Estes CDR, MC USN
    The patient was a 52-year-old white man who had worked in remote areas of the world during the past 2 years, including an extended period in rural areas of Central Africa and in Central and South America. He had no acute illnesses during the 2-year period except for rare, mild, upper respiratory tract infections. For approximately 1 year, however, he had developed recurrent, papular-vesicular, slightly painful lesions on the fingers and palms, that spontaneously healed over weeks to months ( Fig. 1). The patient had no other concurrent illnesses and no abnormal laboratory findings, except for positive enzyme-linked immunoabsorbent assay (ELISA) for immunoglobulin G (IgG) antibodies for hepatitis E virus (HEV) using a recombinant expressed HEV antigen (Genelabs Technologies, Inc., San Antonio). Prolonged treatment with minocycline did not appear to moderate the lesions. At approximately 2.5 years after the development of his first cutaneous lesion, however, the patient reported that he had had no new lesions for over 3 months. Figure 1. Vesicular ,lesion on the finger which regressed over a period of weeks A biopsy specimen showed an intraepidermal vesicle with prominent epidermal necrosis and reticular degeneration ( Fig. 2). Within the epidermis, there was a dense infiltrate of lymphoid cells. The majority of these cells were pleomorphic with prominent nucleoli and frequent mitotic figures ( Fig. 3). Sheets of atypical cells were found in the subjacent dermis. The infiltrate extended down into the reticular dermis. With extension into the dermis, the infiltrate became more polymorphous with more small lymphoid cells, large numbers of eosinophils, and some plasma cells located more deeply. Figure 2. Intraepidermal ,blister showing reticular degeneration and marked epidermotrophism of large atypical cells with extension into the dermis with a mixed infiltrate containing eosinophils and plasma cells (30×) Figure 3. Intraepidermal ,infiltrate of large atypical cells with extension into the dermis with a mixed infiltrate containing eosinophils and plasma cells (400×) Immunohistochemical stains for CD3 (DAKO), CD4 (Becton Dickinson), CD8 (Becton Dickinson), CD15 (LeuM1, Becton Dickinson), CD20 (L-26, DAKO), CD30 (Ber-H2, DAKO), CD45RO (UCHL1, DAKO), S-100 protein (DAKO), T-cell intracellular antigen (TIA) (Coulter), epithelial membrane antigen (EMA) (DAKO), KP-1 (CD68, DAKO), MAC-387 (DAKO), Epstein,Barr virus (EBV) latent membrane antigen-1 (LMP-1, DAKO), and EBV-encoded nuclear antigen 2 (EBNA2, DAKO) were performed on formalin-fixed tissue using the ABC method with DABA as the chromagen. CD3 showed diffuse membrane staining of the large atypical lymphoid cells, as well as the majority of the small lymphoid cells ( Fig. 4). CD4 showed positive membrane staining of the large atypical lymphoid cells and the majority of the small lymphoid cells. CD8 showed only scattered light membrane staining of small lymphoid cells. CD15 was negative, and CD20 showed foci of groups of small lymphoid cells mainly within the reticular dermis. CD30 showed positive membrane and paranuclear staining of the large atypical cells, most abundant within the epidermis and papillary dermis ( Fig. 5). CD45RO showed positive membrane staining of the large atypical cells and the majority of the small lymphoid cells. S-100 protein showed increased dendritic cells within the surrounding viable epidermis and the subjacent papillary dermis ( Fig. 6). TIA showed granular staining in the large atypical lymphoid cells and only rare staining in small lymphoid cells ( Fig. 7). EMA staining was essentially negative. KP-1 showed only scattered positive cells mainly in the lower papillary and the reticular dermis. MAC-387 showed membrane staining in the viable epidermis ( Fig. 8). LMP-1 and EBNA2 for EBV were negative within the lymphoid cells as well as within the overlying epidermis. Figure 4. Immunohistochemical ,staining for CD3 showing diffuse staining of lymphoid cells within the epidermis and dermis (150×) Figure 5. Immunohistochemical ,staining for CD30 showing membrane and paranuclear staining of large atypical lymphoid cells within the epidermis and papillary dermis (a, 150× b, 400×) Figure 6. Immunohistochemical ,staining for S-100 protein within the epidermis and in the papillary dermis (a, 150× b, 300×) Figure 7. Immunohistochemical ,granular staining of large atypical lymphoid cells for TIA (200×) Figure 8. Immunohistochemical ,staining for MAC-387 showing epidermal staining (100×) Gene rearrangement studies showed a ,-T-cell receptor gene rearrangement. The monoclonal band was detected with VJ1, VJ2, and D1J2 primer sets. The T-cell receptor , rearrangement assay has a sensitivity of 61% and a specificity of 94% for the detection of a monoclonal rearrangement in T-cell lymphomas for which amplifiable DNA can be recovered. Electron microscopy was performed on formalin-fixed material, positive-fixed with 2.5% phosphate-buffered glutaraldehyde and further with 1% osmium tetroxide by standard techniques. Intracellular, 50,60-nm, cytoplasmic, spherical, viral-like particles were identified ( Fig. 9). Figure 9. Electron ,microscopy showing 50,60-nm diameter, intracellular, viral-like particles (arrows) (70,000×) [source]


    Low-grade renal epithelial tumor originating from the distal nephron

    INTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2004
    NOBORU HARA
    Abstract, There are few published reports of low-grade renal epithelial tumor originating from the distal nephron. However, it should not be disregarded clinically, because the actual number of patients with such tumors may be higher than expected. We investigated the immunohistochemical profile of a histologically distinct subtype of such a tumor in detail, in addition to the clinical course and imaging studies. The present study demonstrated that both glandular and spindle cell components of this tumor have a persistent characteristic of an epithelial tumor arising from the distal tubule or collecting duct. This tumor is a benign complex neoplasm that can be treated successfully with radical surgery. Beta-catenin and E-cadherin are suggested to play a crucial role in tumorigenesis and the biphasic arrangement of this neoplasm, concerning the expression of epithelial membrane antigen and carbohydrate antigen 19-9. We suggest that the term ,distal nephron epithelioma' is appropriate for classifying such rare but clinicopathologically distinct tumors. [source]


    Giant clear cell hidradenoma of the knee

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 9 2010
    Gengsheng Yu
    Hidradenomas, also referred to as nodular hidradenomas or clear cell hidradenomas (CCH), are benign cutaneous eccrine tumors usually 2,3 cm in dimension. Hidradenomas are relatively common; however, giant forms are rare. We report a case of an 8.0 × 6.0 × 3.0 cm clear cell hidradenoma of the left knee in a 43-year-old man. The tumor was mobile, located above the patellar tendon and was without bony involvement on imaging studies. Grossly, the resected tumor was unencapsulated and tan, with a solid and cystic cut surface showing papillary excrescences on the cyst wall. Microscopically, the tumor cells showed an infiltrative growth pattern at the periphery, however, the tumor cytology was bland and no necrosis or mitoses were identified. The overlying dermis contained hemosiderin pigment deposition and infiltration with eosinophils. Immunohistochemically, tumor cells were positive for cytokeratin, CAM5.2, p53, carcino-embryonic antigen (CEA) and epithelial membrane antigen (EMA), and negative for CD10 and Ki-67. The cytological features of hidradenomas can present diagnostic challenges, as other ,clear cell' tumors such as metastatic renal cell carcinoma should be considered. Immunohistochemical studies and differential diagnoses are discussed. Yu G, Goodloe S, D'Angelis CA, McGrath BE, Chen F. Giant clear cell hidradenoma of the knee. [source]


    Fibroblastic rheumatism: fibromatosis rather than non-Langerhans cell histiocytosis

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2010
    Nicolas Kluger
    Background: Fibroblastic rheumatism is a unique fibro-proliferative disease affecting the skin and joints. It is characterized by distinctive clinical and histological features related to benign spindle-shaped cells proliferation. Pediatric reports are scarce in the literature. Objective: We describe here a new case in a 10-year-old boy and discuss the potential origin of the cell proliferation. Methods: Clinical findings, radiology, microscopic examination and outcome are reviewed. Histopathology and immunochemistry studies were performed on skin biospies using CD68, CD163, desmin, factor XIIIa, CD34, smooth muscle actin, PS100, epithelial membrane antigen, and calponin. Results: Histological sections disclosed a rather circumscribed nonencapsulated nodular infiltrate, invading the dermis and the upper subcutaneous tissue, consisted of a proliferation of spindle or stellate-shaped cells and thickened collagen fibers. Orcein staining showed disappearance of the elastic network. Aponeurosis and muscle were normal. A mild perivascular lymphohistiocytic infiltrate was noted. Calponin-staining was less strongly expressed as SMA, and some of them but not all were CD68 positive, as well. On the other hand, all were CD34, CD163, FXIIIa, PS100, EMA and desmin-negative. Conclusion: The true origin of these cells remains unclear. Some authors have speculated a histiocytic origin. However, immuno-chemical staining in our case failed to confirm this hypothesis and instead supported a fibroblastic/myofibroblastic origin. Given the clinical course and the histological and immunohistochemical results, we suggest that FR should be added to the group of fibromatoses. Kluger N, Dumas-Tesici A, Hamel D, Brousse N, Fraitag S. Fibroblastic rheumatism: fibromatosis rather than non-Langerhans cell histiocytosis. [source]


    Clear cell myoepithelial carcinoma of the skin.

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2009
    A case report
    Myoepitheliomas are tumors of myoepithelial cells, most frequently diagnosed in the salivary glands. Cutaneous location is very rare, especially for malignant variant. We report a case of recurrent cutaneous myoepithelial carcinoma of the femoral region in a 51-year-old woman. Histologically, the tumor was confined to the dermis and superficial subcutaneous fat tissue, exhibiting typical multinodular pattern. The majority of tumor cells were of clear cell type, although rare epithelioid and spindle cells were also present. Nuclear atypia, mitotic activity of 12 mitoses per 10 microscopic high power fields and Ki-67 labeling index of 20%, as well as three recurrences, corroborated the malignant nature of the tumor. Immunohistochemistry showed positivity for cytokeratin, epithelial membrane antigen, vimentin, S-100 protein and myogenic markers (,-smooth muscle actin and muscle-specific actin HHF-35) in keeping with the myoepithelial cell immunophenotype. Staining for CD34, desmin and HMB-45 was negative. Myoepithelial carcinoma should be considered in the differential diagnosis of cutaneous neoplasms composed predominantly of clear cells. [source]


    Epithelioid sarcoma with angiomatoid features: report of an unusual case arising in an elderly patient within a burn scar

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 3 2008
    Steven Kaddu
    Epithelioid sarcoma (ES) is a rare, aggressive soft tissue tumor with a characteristic predilection for adolescents and young adults, and a tendency to occur on distal extremities. We report a case of ES arising in an 80-year-old woman within a burn scar that histopathologically showed unusual ,angiomatoid' features. The patient presented initially with a solitary nodule on her right wrist arising at the site of a burn scar. Histopathologically, the tumor was composed of a proliferation of relatively bland, epithelioid and spindle cells focally arranged in a nodular pattern around areas of ,geographic' necrosis. In addition, there were prominent foci of hemorrhage and blood-filled spaces as well as tumor cells with intracytoplasmic vacuoles, features suggestive of an angiomatous process. Immunohistochemistry showed positivity of tumor cells for cytokeratins and epithelial membrane antigen (EMA) whereas all vascular markers tested were negative. The overall histopathologic features were consistent with a diagnosis of ES. Follow up showed multiple recurrences arising proximally along the right upper extremity. Our case underlines the clinical and histopathological heterogeneity of ES, emphasizing the unusual occurrence of ES with ,angiomatoid' features in the elderly. In this uncommon setting, this tumor should be especially distinguished from epithelioid hemangioendothelioma and epithelioid angiosarcoma. The significance of development of ES on a healed burn scar is uncertain, but may suggest a possible causal relationship. [source]


    Soft-tissue perineurioma in a 20-year-old patient with neurofibromatosis type 1 (NF1): report of a case and review of the literature

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 9 2007
    Gregory G. Ausmus
    Background:, Perineurioma is a rare benign soft-tissue tumor composed of cells showing differentiation toward the perineurial cells of the nerve sheath. Although mutations in the neurofibromatosis 2 (NF2) gene have been documented in this tumor, there is no known association between perineuriomas and type 1 or 2 NF. Methods:, This is the first report of a case of soft-tissue perineurioma occurring in a patient with NF1. Results:, Histopathologic examination revealed a 2.0-cm well-circumscribed, spindle-cell neoplasm with slender, elongated, bipolar, wavy cytoplasmic processes and wavy, elongated nuclei in a hyalinized stroma with focal myxoid areas. The architecture was composed predominantly of short fascicles with areas exhibiting a storiform pattern. Immunohistochemistry showed positive labeling for epithelial membrane antigen (EMA) but no staining for S-100 and smooth muscle actin (SMA). Conclusion:, This case illustrates that perineurioma can occur in association with NF1. Perineuriomas can be confused with other spindle-cell neoplasms, and relevant features and immunohistochemistry of these lesions are outlined. The patient has not had a recurrence with limited follow-up. [source]


    Sarcomatoid eccrine porocarcinoma: report of two cases and a review of the literature

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2007
    Seng Geok Nicholas Goh
    To the best of our knowledge, there has been no report in the English literature of porocarcinoma with predominantly undifferentiated sarcomatous change. We present two cases of sarcomatoid eccrine porocarcinoma associated with a benign poroma. Case 1 pertained to an 82-year-old woman with an ulcerated chest wall tumor, and Case 2 was that of a 74-year-old woman who presented with an ulcerated plaque in the lower leg. Case 1 showed an unusual pseudo-angiosarcomatous morphology with spindle cells dissecting through collagen bundles and forming vascular like channels. Case 2 revealed high-grade malignant spindle cells with focal evidence of ductal differentiation. In both the cases, benign poromatous elements were histologically evident. Immunohistochemistry performed showed pancytokeratin positivity in spindle cells of both lesions. Epithelial membrane antigen and carcino-embryonic antigen positivity in the malignant ductal elements and focal smooth muscle actin staining of the spindle cells were demonstrated in Case 2. A brief review of relevant literature is presented. [source]


    Hidradenocarcinoma: Criteria for Malignancy and Hypothesis of an Apoeccrine Origin

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005
    C. Ko
    The immunohistochemical profile of hidradenocarcinoma, defined here as the malignant counterpart of hidradenoma, has not been well characterised. We evaluated the staining pattern of six cases of hidradenocarcinoma using antibodies to gross cystic disease fluid protein-15 (GCDFP-15), carcino-embryonic antigen (CEA), epithelial membrane antigen (EMA), S-100 protein, keratin AE1/3, cytokeratin 5/6, p53, bcl-1, bcl-2, and Ki67. All tumours were poorly circumscribed with clefting between tumour and stroma, evidence of poroid cells and cuticular cells, decapitation secretion, and increased mitoses with cords of tumour infiltrating through the adjacent desmoplastic stroma. The tumours stained with antibodies to CEA, S-100 protein, GCDFP-15, and EMA in no consistent pattern. All tumours studied stained positively for keratin AE1/3 and cytokeratin 5/6. Ki67 and p53 staining were strongly positive in 5 of 6 tumours. Bcl-1 and bcl-2 staining were variable. Our study demonstrates that hidradenocarcinomas may have both apocrine and eccrine features within the same tumour and suggests that it may be most accurate to consider that these tumours originate from apoeccrine structures or stem cells with the capacity for pluripotential differentiation. [source]


    Lymphoepithelioma-Like Carcinoma of the Skin: A Case Report

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005
    T. Mitsuhashi
    Lymphoepithelioma-like carcinoma of the skin is a rare tumor with a microscopic resemblance to lymphoepitheliomatous carcinoma of the nasopharynx. We present a 93-year-old man with papules on the left auricle to the cheek that were gradually enlarged. By the time of a biopsy, it grew to a 5.0 × 3.0 × 2.8 cm dark red mass, and necrotic debris was attached to the surface. Histologically, a relatively well-demarcated, dermal-hypodermic multiple lobules were composed of irregular islands of atypical epithelial cells. The uniform tumor cells had moderate amounts of lightly eosinophilic cytoplasm and vesicular nuclei with one or two prominent nucleoli. A dense lymphocytic infiltrate was present within the neoplastic islands, obscuring the epithelial component. The neoplastic cells were unconnected to the overlying epidermis. Neither squamous nor glandular differentiation was present. Immunohistochemically, the neoplastic cells were positive for epithelial membrane antigen and cytokeratin, and negative for latent membrane protein 1. No Epstein-Barr virus-encoded RNA (EBER) was detected by in situ hybridization. The negativity for Epstein-Barr virus may be a help in the differential diagnosis from metastatic undifferentiated nasopharyngeal carcinoma, which is uniformly positive for EBER. [source]


    Pigmented squamous cell carcinoma of the skin: morphologic and immunohistochemical study of five cases

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 8 2000
    Michael B. Morgan
    Invasive pigmented squamous cell carcinoma (PSCC) of the skin is reportedly rare. Herein, we evaluate an additional five cases and compare their relative frequency with non-pigmented squamous cell carcinoma (SCC). Of 46,791 archived cases of SCC, a total of five cases of PSCC were discovered for a relative frequency of ,0.01%. Grossly, each tumor presented as a rapidly growing crusted papule on actinic damaged skin of the face. Microscopically, all were composed of a mixture of keratininized squamous cells and melanin-producing dendritic melanocytes. The squamous cells stained for epithelial membrane antigen, and both low and high molecular keratins. The melanocytes stained for S-100 and HMB-45. A matched series of 31 SCCs were subjected to an identical immunohistochemical battery of stains to determine if a histologically subtle and unsuspected number of intratumoral melanocytes existed in SCC. Each of the cases failed to show intratumoral melanocytes. The differential diagnosis and possible histogenesis of PSCC is discussed and the importance of extensive pathologic examination to prevent misdiagnosis is emphasized. Despite the histologic dissimilarity, the long-term prognosis of the reported cases was similar to conventional SCC. [source]


    Biochemical characterization of human glutamate carboxypeptidase III

    JOURNAL OF NEUROCHEMISTRY, Issue 3 2007
    Klára Hlouchová
    Abstract Human glutamate carboxypeptidase II (GCPII) is a transmembrane metallopeptidase found mainly in the brain, small intestine, and prostate. In the brain, it cleaves N -acetyl- l -aspartyl-glutamate, liberating free glutamate. Inhibition of GCPII has been shown to be neuroprotective in models of stroke and other neurodegenerations. In prostate, it is known as prostate-specific membrane antigen, a cancer marker. Recently, human glutamate carboxypeptidase III (GCPIII), a GCPII homolog with 67% amino acid identity, was cloned. While GCPII is recognized as an important pharmaceutical target, no biochemical study of human GCPIII is available at present. Here, we report the cloning, expression, and characterization of recombinant human GCPIII. We show that GCPIII lacks dipeptidylpeptidase IV-like activity, its activity is dependent on N -glycosylation, and it is effectively inhibited by several known inhibitors of GCPII. In comparison to GCPII, GCPIII has lower N -acetyl- l -aspartyl-glutamate-hydrolyzing activity, different pH and salt concentration dependence, and distinct substrate specificity, indicating that these homologs might play different biological roles. Based on a molecular model, we provide interpretation of the distinct substrate specificity of both enzymes, and examine the amino acid residues responsible for the differences by site-directed mutagenesis. These results may help to design potent and selective inhibitors of both enzymes. [source]


    Promising tumor-associated antigens for future prostate cancer therapy

    MEDICINAL RESEARCH REVIEWS, Issue 1 2010
    Yong Li
    Abstract Prostate cancer (CaP) is one of the most prevalent malignant diseases among men in Western countries. There is currently no cure for metastatic castrate-resistant CaP, and median survival for these patients is about 18 months; the high mortality rate seen is associated with widespread metastases. Progression of CaP from primary to metastatic disease is associated with several molecular and genetic changes that can affect the expression of specific tumor-associated antigens (TAAs) or receptors on the cell surface. Targeting TAAs is emerging as an area of promise for controlling late-stage and recurrent CaP. Several reviews have summarized the progress made in targeting signaling pathways for CaP but will not be discussed here. We describe some important CaP TAAs. These include prostate stem-cell antigen, prostate-specific membrane antigen, MUC1, epidermal growth factor receptor, platelet-derived growth factor and its receptor, urokinase plasminogen activator and its receptor, and extracellular matrix metalloproteinase inducer. We summarize recent advancements in our understanding of their role in CaP metastasis, as well as potential therapeutic options for targeting CaP TAAs. We also discuss the origin, identification, and characterization of prostate cancer stem cells (CSCs) and the potential benefits of targeting prostate CSCs to overcome chemoresistance and CaP recurrence. © 2009 Wiley Periodicals, Inc. Med Res Rev, 30, No. 1, 67,101, 2010 [source]


    Pinealoblastoma with prominent retinoblastic differentiation: An unusual case in an adult

    NEUROPATHOLOGY, Issue 4 2010
    Nandita Ghosal
    We present an extremely rare case of pinealoblastoma with retinoblastic differentiation in a 32-year-old woman who presented with a history of intermittent headache of 2 years duration and diminution of vision for 2 months which eventually lead to total loss of vision. The fundus examination showed bilateral secondary optic atrophy. She did not have any previous history of retinoblastoma. The family history was non-contributory. Paraffin section of the tumor showed a primitive neuroectodermal tumor with numerous Flexner-Wintersteiner rosettes and the tumor cells were strongly positive for synaptophysin and negative for GFAP, S-100 protein and epithelial membrane antigen. This is the first case in the literature of a sporadic case of pinealoblastoma with prominent retinoblastic differentiation as evidenced histomorphologically by the presence of numerous Flexner-Wintersteiner rosettes in an adult female. [source]


    Malignant solitary fibrous tumor arising from the pineal region: case study and literature review

    NEUROPATHOLOGY, Issue 3 2010
    Jing Zhang
    We report a case of malignant solitary fibrous tumor involving the pineal region in a 49-year-old woman. The patient presented with headache, slowly progressive weakness of the right lower extremities and upgaze palsy over the past year. Histologically, the tumor was composed of moderately hypercellular proliferated spindle cells with eosinophilic collagen bands. These cells were diffusely and strongly immunoreactive with CD34, CD99, and vimentin, but were negative with epithelial membrane antigen, S-100 protein, Bcl-2, smooth muscle actin, cytokeratin and glial fibrillary antigenic protein. MIB-1 labeling indices and mitosis rates were 7.3 ± 1.8% and 5 per 10 high power fields, respectively. Ultrastructural examination revealed that the neoplastic cells had features of fibroblastic differentiation. Differential diagnoses included fibrous meningioma and hemangiopericytoma. The present case provides one unique example of a rare entity to the already diverse spectrum of the pineal region neoplasms encountered in neuropathology. [source]


    Intraventricular metaplastic meningioma in a child: case report and review of the literature

    NEUROPATHOLOGY, Issue 6 2009
    Mohanpal Singh Dulai
    Childhood meningiomas are rare and display important differences from adult forms. We report the first case of an intraventricular metaplastic meningioma arising in a child. A 7-year-old female underwent resection of an enhancing tumor arising within the left lateral ventricle. It was composed of monomorphic cells embedded within an abundant myxoid stroma. The cells demonstrated epithelial membrane antigen and vimentin immunoreactivity. Ultrastructural analysis demonstrated intermediate filaments, complex intercellular interdigitations and desmosomes, and a diagnosis of myxoid (metaplastic) meningioma was rendered. This case reflects the higher incidence of intraventricular meningiomas in childhood and greater incidence of intraventricular meningiomas in the left lateral ventricle. Recognition of the grade I myxoid meningioma in this case is paramount since chordoid meningiomas, which share similar histologic features, are of a higher grade and worse prognosis. [source]


    Astroblastoma: Immunohistochemical and ultrastructural study of distinctive epithelial and probable tanycytic differentiation

    NEUROPATHOLOGY, Issue 1 2006
    Toshihiko Kubota
    We report the clinicopathological findings of astroblastoma found in an 8-year-old girl who was subsequently treated for 11 years. The primary superficially circumscribed tumor was located in the frontoparietal lobe, while the recurrent and the second recurrent tumor were restricted to the same region 11 years later. The tumors obtained on these three occasions showed fundamentally the same histological, immunohistochemical and fine structural features. They exhibited astrocytic as well as ependymal tanycytic features with apparent epithelial cell lineage. The tumor cells showed typical features of astroblastoma comprising prominent perivascular pseudorosettes with remarkable vascular sclerosis. The immunohistochemical study revealed intensive positivity of GFAP, vimentin, epithelial membrane antigen (EMA), cytokeratin, connexin 26 and 32, desmocollin 1 and neuronal cadherin. The fine structure revealed divergent types of junctional complexes, some of which were connected with tonofilament bundles. Numerous microvilli protruded and basal lamina abutted on the tumor cell surface. We report these unique histological features, and stress that astroblastoma should be categorized as a specific type of neuroepithelial tumor. [source]


    Chordoid meningioma: Rare variant of meningioma

    NEUROPATHOLOGY, Issue 3 2004
    Özlem Özen
    Chordoid meningioma is a rare variant of meningioma that bears a striking histological resemblance to chordoma and has greater likelihood of recurrence. Although most meningiomas occur in the intracranial, orbital and intravertebral cavities, rare meningiomas have been reported in extracranial organs; thus, it is important to be able to distinguish them from other neoplasms that have similar histology but different biological behavior and therapies. A case of chordoid meningioma in a 48-year-old woman who did not have Castleman's syndrome is described in the present report. The patient presented with a mass in her left frontoparietal region, and had been suffering from headaches for many years. Magnetic resonance imaging of the brain demonstrated an expansive lytic lesion in the squamous portion of the left temporal bone. The lesion extended in both directions. Histological examination of the surgical specimen revealed a tumor composed of cords and nests of eosinophilic vacuolated cells embedded in a myxoid matrix. A typical meningiomatous pattern was observed focally, and positive staining of the tumor cells for vimentin and epithelial membrane antigen confirmed the diagnosis of chordoid meningioma. [source]


    Third ventricular chordoid glioma: clinicopathological study of two cases with evidence for a poor clinical outcome despite low grade histological features

    NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2005
    K. M. Kurian
    Chordoid glioma of the third ventricle is a rare glial tumour whose precise histogenesis remains uncertain. We describe two cases that presented recently to our department and review the background literature. The neoplasm tends to occur in women and its clinical presentation is variable, resulting from acute hydrocephalus or impingement upon local structures. However, the radiological appearance is distinct, with an ovoid shape, hyperdensity and uniform contrast enhancement on computerized tomography and magnetic resonance imaging. Intraoperative smear diagnosis is difficult because of the lack of specific features, although the presence of metachromatic extracellular mucin may be useful. The characteristic histological appearance is that of cords and clusters of cohesive, oval-to-polygonal epithelioid cells with abundant eosinophilic cytoplasm and a mucinous background. There is often a mixed chronic inflammatory infiltrate with lymphocytes and plasma cells with Russell bodies. The main differentials for histological diagnosis include chordoid meningiomas, pilocytic astrocytomas and ependymomas. An immunohistochemical panel including antibodies to glial fibrillary acidic protein, CD34, epithelial membrane antigen, pan cytokeratin, S100 and vimentin can be used to distinguish between these possibilities. Ultrastructurally the tumour cells have basal lamina and microvilli, reminiscent of ependymomas. The clinical outcome in our cases was poor because of the location of the lesion and its close relation to the hypothalamus. Limited follow-up after surgery with or without radiotherapy suggests that as-full-as-possible resection favours a better outcome, although surgery in this area carries significant operative risks. [source]


    Adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of minor salivary glands: a comparative immunohistochemical study using the epithelial membrane and carcinoembryonic antibodies

    ORAL DISEASES, Issue 3 2005
    A Epivatianos
    Objective:, The purpose of this study was to investigate immunohistochemically the expression of epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA) in adenoid cystic carcinoma (AdCC) and polymorphous low-grade adenocarcinoma (PLGA) in an attempt to assess the ability of these markers to distinguish AdCC from PLGA when the histological features on routine hematoxylin and eosin are equivocal. Materials and methods:, Fourteen specimens of AdCC, 10 PLGA, and five normal minor salivary glands fixed in 10% formalin and embedded in paraffin, were retrieved from the files of our department and were retrospectively studied with the streptavidin-biotin complex method using the epithelial membrane and carcinoembryonic antibodies. Results:, The immunoreactivities and the expression patterns of EMA and CEA in AdCC and PLGA were similar. Conclusions:, The results of this study suggest that the immunostaining of AdCC and PLGA with EMA and CEA could not offer an adjunctive aid in differential diagnosis between these two tumors. [source]