Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myoepitheliomas of the breast are extremely rare; only four cases have been reported to date. It is not clear whether these tumors behave in a benign or malignant fashion, and no metastatic spread has been documented. We report a myoepithelioma of the breast with metastatic spread to an axillary lymph node. Myoepithelial cell (MEC) differentiation in the tumor was characterized using electron microscopic (EM) criteria. Immunologic investigations at the LM and EM levels showed that the tumor cells were positive for S100 protein, actin, and epidermal cytokeratin; these findings are indicative of MEC differentiation. By immuno-EM, cytokeratin filaments were present in a perinuclear location, while actin filaments were concentrated along the cell periphery. To the authors' knowledge, this is the first report of a breast myoepithelioma that has metastasized and also the first report of the immunologic characterization of a myoepithelioma at the light and electron microscopic levels.
 ...
PMID:Malignant myoepithelioma of the breast. An immunohistochemical study by light and electron microscopy. 241 82

Nephroblastomas (Wilms' tumors) from a dog, a bird, a pig, and a child were subjected to comparative immunocytochemical and lectin-histochemical analysis along with normal renal tissues from the same animals. Primary rabbit and mouse anti-human antibodies directed at intermediate-filament proteins, neuron-specific enolase, S100 protein, and epithelial membrane antigen were employed, as were biotinylated peanut agglutinin, soybean agglutinin, wheat germ agglutinin, and lectins from Dolichos biflorus and Ulex europaeus. The human neoplasm showed positivity for cytokeratin and epithelial membrane antigen and bound peanut, soybean, and wheat germ agglutinins in epithelial areas. Among the animal tumors, the porcine and canine nephroblastomas showed immunoreactivity for cytokeratin and vimentin in epithelial and blastematous areas, respectively. In addition, they were positive for S100 protein in epithelial foci. All of these results were substantiated by staining patterns in nonhuman kidneys. None of the neoplasms or renal tissues showed reactivity to the other antigens that were assessed. In the porcine tumor, endothelial cells bound D biflorus lectin, and epithelial areas were stained by U europaeus lectin. The avian nephroblastoma bound peanut, soybean, and wheat germ agglutinins, while the canine neoplasm showed no lectin-histochemical reactivity. These data appear to reflect limited immunohistological and histochemical similarities between nephroblastomas of different vertebrates.
 ...
PMID:Nephroblastoma. A comparative immunocytochemical and lectin-histochemical study. 242 98

The malignant intraepithelial proliferations--malignant melanoma level I, bowenoid epithelial dysplasia, and mammary as well as extramammary Paget's disease--may cause differential diagnostic difficulties. We have examined 12 cases of malignant melanoma level I, nine cases of bowenoid epithelial dysplasia, 17 cases of extramammary and five cases of mammary Paget's disease for S100 protein, carcinoembryonic antigen (CEA), cytokeratin, and keratin to evaluate the sensitivity and specificity of these reactions with regard to their differential diagnostic value. Antibodies against S100 reacted specifically with the tumor cells in intraepithelial malignant melanomas; antibodies against CEA reacted specifically with the tumor cells in Paget's disease; and cytokeratin and keratin antibodies reacted with the epithelial tumor cells in Paget's disease as well as in bowenoid epithelial dysplasia. However, only antibodies to CEA and keratin showed 100% sensitivity. We conclude that the investigated antibodies may be of differential diagnostic value in cases of intraepidermal neoplasias, but that a negative reaction does not exclude diagnosis of these diseases.
 ...
PMID:The differential diagnosis of intraepidermal malignant lesions using immunohistochemistry. 242 74

We present a case report of osteoclast-type giant cell tumor of the pancreas and review the literature concerning this rare neoplasm, the histogenesis of which is uncertain. Electron microscopic features have suggested stromal, histiocytic, and epithelial origins to different investigators. Analysis of the present case supports and epithelial origin, with positive immunocytochemical staining for carcinoembryonic antigen and for low molecular weight keratin in the mononuclear and in some osteoclastlike giant cells. These tumor cells did not stain for mesenchymal markers (lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, S100 protein). Zymogen granules, desmosomes, and zonulae occludentes were identified ultrastructurally and further support an epithelial derivation.
 ...
PMID:The osteoclast-type giant cell tumor of the pancreas. 243 51

Ten cases of dedifferentiated chondrosarcoma (DCS) were immunohistochemically and histochemically compared with 12 de novo malignant fibrous histiocytomas, 10 osteoblastic osteosarcomas, 9 conventional chondrosarcomas, and 4 fibrosarcomas (all of bone or soft tissues), in order to discern similarities and differences in the immunophenotypes of these neoplasms. All cases of DCS and malignant fibrous histiocytoma were reactive for alpha-1-antichymotrypsin, and several examples of both tumor types bound peanut agglutinin, and expressed positivity for alpha-1-antitrypsin and lysozyme. None of these four cellular markers was observed in de novo osteosarcoma and fibrosarcoma; in addition, conventional chondrosarcoma lacked all of them except for peanut agglutinin receptors. S100 protein reactivity and binding of wheat germ agglutinin were detectable in conventional chondrosarcomas and in rare cells of the anaplastic components of primary DCS, but not in malignant fibrous histiocytoma arising ab initio and the other sarcomas. These results suggest the evolution of a second neoplastic cellular clone in DCS, with primitive morphological and phenotypic characteristics.
 ...
PMID:Dedifferentiated chondrosarcoma of bone. An immunohistochemical and lectin-histochemical study. 243 90

Immunohistochemical analysis of 21 prototypic mucosal spindle-cell carcinomas of the aerodigestive tract was performed at the Armed Forces Institute of Pathology (AFIP) to establish the usefulness of selected immunohistochemical markers in distinguishing spindle-cell carcinoma from other mucosal spindle-cell neoplasms. Immunoreactive keratin could be demonstrated in only 13/21 (62%) of cases. Coexpression of keratin and vimentin was demonstrated in 10/17 (59%) of the tumors evaluated for both of these intermediate filaments. All spindle-cell carcinomas lacked S100 protein, which is an immunoreactivity we would expect to find in spindle-cell malignant melanoma, one of the principal considerations in a differential diagnosis. Both alpha-1-antitrypsin (AAT) and alpha-1-antichymotrypsin (ACT) were demonstrated in the tumor cells in all cases. However, albumin had a similar distribution in the tumors, which suggested that passive uptake was a serious confusing factor. The results of this study indicate that AAT and ACT are unreliable markers for distinguishing spindle-cell carcinomas from malignant fibrous histiocytomas.
 ...
PMID:Spindle-cell carcinoma of the aerodigestive tract. An immunohistochemical analysis of 21 cases. 243 12

In an attempt to characterize the immunocytochemical attributes of eccrine sweat gland carcinoma, we studied 32 examples of this tumor with antibodies to epithelial membrane antigen (EMA), cytokeratin (CK), carcinoembryonic antigen, S100 protein, alpha-lactalbumin, salivary amylase, blood group isoantigens, beta-2-microglobulin, and Leu M1. All cases expressed EMA and CK, and 28 of 32 cases also displayed at least 2 of the 6 remaining antigens. No significant variations were noted in the immunophenotypes of histologic subtypes of eccrine carcinoma. These results provide an objective means of diagnostic separation between sweat gland carcinoma and other primary malignant cutaneous tumors. However, they do not appear to correlate with the degree of tumoral differentiation, and are of no assistance in the separation of benign and malignant sudoriferous neoplasms. The ability of immunocytochemical techniques to distinguish between primary malignant adnexal cutaneous tumors and metastases to the skin appears unlikely, but remains to be studied further. Also, the use of immunostaining panels is advised in the study of adnexal carcinomas, since no single determinant in isolation is specific for these neoplasms.
 ...
PMID:Eccrine sweat gland carcinoma: an histologic and immunohistochemical study of 32 cases. 243 58

This is a unique case of chondroid chordoma arising in the sacrococcygeal area of an asymptomatic man. S100 protein was detected in both chondroid and chordoid tissues; epithelial membrane antigen (EMA) and cytokeratin were present in abundant amounts in the cytoplasm of chordoma cells but not in chondroid cells. The presence of cytokeratin and EMA in chordoma implies the epithelial nature of the tumor and is extremely helpful as a differential marker for chordoma. I suggest that EMA, cytokeratin, and S100 protein should be used conjunctively to provide a resolution for difficult diagnostic problems when dealing with chordomas, especially with their variants, such as chondroid chordomas, which often cause further confusion.
 ...
PMID:Chondroid chordoma of the sacrococcygeal region. 244 6

Adenoid cystic carcinoma is a specific variant of adenocarcinoma with a characteristic cribriform appearance. The tumor may arise from salivary glands and various other sites, but the origin and cellular composition of this unique neoplasm have been controversial. A potential use of immunohistochemistry is to provide additional information on the origin of various cellular components of tumors by comparing them with corresponding normal tissues. Immunohistochemical distributions of carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), keratin, low molecular weight keratin (54 kd), S100 protein, muscle-specific actin, laminin, and type IV collagen were evaluated in 20 adenoid cystic carcinomas arising in major and minor salivary glands. Anti-CEA, anti-EMA, anti-keratin, and anti-S100 antibodies strongly stained cells lining true lumina. Muscle-specific actin, a marker for myoepithelial cells, was found in lining cells of pseudocysts, in tumor cells proper, and in nonluminal cells with a tubular growth pattern. A monoclonal antibody against 54 kd keratin stained almost all cells in the neoplasms. In pseudocysts, replicated basal lamina reacted with antisera to laminin and to type IV collagen. The present study demonstrates that there are at least two populations of tumor cells in adenoid cystic carcinoma: luminal cells that express CEA and EMA, thus indicating their ductal character, and nonluminal cells that express muscle-specific actin characteristic of myoepithelium.
 ...
PMID:Adenoid cystic carcinoma of the salivary glands: an immunohistochemical analysis. 245 Nov 97

Basal cell carcinoma displays a myriad of histopathologic variants, some of which are related to the different lines of differentiation, vis-a-vis, squamous, pilar, eccrine, or sebaceous. We herein report an example of a rare signet-ring, clear-cell variant. Our diagnosis is primarily based on the histopathologic features of the tumor, namely, the dermal nests of tumor cells with peripheral palisading and focally retracted fibroblastic stroma. Several nests are folliculocentric. The tumor cells are glycogen-rich, mucin-negative, pankeratin-positive, cytokeratin-negative, S100 protein-negative, and carcinoembryonic antigen-negative. Based on the histopathology and the results of the special stains we propose that the signet-ring clear-cell variant of basal cell carcinoma is differentiating in the direction of the outer root sheath cells of the pilar structure.
 ...
PMID:Signet-ring clear-cell basal cell carcinoma. 245 18


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>