epithelial membrane antigen (EMA),

a heavily glycosylated, 70-kD protein complex, first isolated in human milk fat globulin; this antigen is present in a variety of glandular epithelia, especially in breast carcinoma cells but may also be seen in cultured fibroblasts, lymphoid cells, and some stromal cells. Immunohistochemical staining may aid in tissue diagnosis.

Farlex Partner Medical Dictionary © Farlex 2012

epithelial membrane antigen

A 265–400-kD transmembrane glycoprotein found in milk-fat globule membranes.

Normal expression
Normal epithelia and perineurial cells.

Abnormal expression
Neoplastic epithelia and perineurial cells, meningioma, mesothelioma, mesenchymal tumours, some lymphomas, choroid plexus, arachnoid granulation, epithelioid histiocytes, anaplastic large cell lymphomas.

ep·i·the·li·al mem·brane an·ti·gen

(EMA) (ep'i-thē'lē-ăl mem'brān an'ti-jen)

A heavily glycosylated, 70-kD protein complex, first isolated in human milk fat globulin; this antigen is present in a variety of glandular epithelia, especially in breast carcinoma cells, but may also be seen in cultured fibroblasts, lymphoid cells, and some stromal cells. Immunohistochemical staining may be used as a diagnostic aid in tissue diagnosis.

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

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References in periodicals archive

Ber EP4 and epithelial membrane antigen aid distinction of basal cell, squamous cell and basosquamous carcinomas of the skin.

Sebaceous carcinoma of the right arm

By 1993 it was realized that there is a strong and diffuse membranous BerEP4 staining in all subtypes of BCC; which were all negative for epithelial membrane antigen (EMA)9.

SENSITIVITY AND SPECIFICITY OF BEREP4 IMMUNOSTAINING IN BASAL CELL CARCINOMA CASES IN ASIAN SKIN

Staining for the carcinoembrionary antigen (CEA) and the epithelial glycoprotein Ber-EP4 was negative, whereas results for the mesothelial markers cytokeratins, calretinin (Figure 2), epithelial membrane antigen (EMA), and HBME-1 (Figure 3) were positive, leading to the diagnosis of peritoneal epithelial mesothelioma.

Asbestos-induced peritoneal mesothelioma in a construction worker

It has been suggested that at a minimum, an IHC panel of PAS with diastase, vimentin, and a pan-cytokeratin or epithelial membrane antigen should be included in evaluating signet ring cell tumors of the ovary.

Signet Ring Stromal Cell Tumor: A Legitimate (Benign) Mimic of Krukenberg Tumor

The majority of germ cell neoplasms stain positively with placental alkaline phosphatase (PLAP) and negatively with epithelial membrane antigen (EMA).

A rare case report of mixed germ cell tumor (seminoma, embryonal carcinoma, yolk sac tumour and immature teratoma) of testis

CK - cytokeratin, MMAH - monoclonal mouse antihuman, EMA - epithelial membrane antigen SMA - smooth muscle actin.

Atypical fibroxanthoma with dermal amyloid deposit

Immunohistochemical studies indicate that the epithelial membrane antigen (EMA) marker may be present; that the epithelial cells may stain positive for keratin markers, including CAM5.2; and that the myoepithelial cells may stain positive for S-100.

Chondroid syringoma of the scalp: case report and discussion of clinical features, histopathology, and treatment

The use of immunohistochemistry in distinguishing reactive from neoplastic mesothelium: a novel use for desmin and comparative evaluation with epithelial membrane antigen, p53, platelet-derived growth factor-receptor, P-glycoprotein and Bcl-2.

Cytopathologic Diagnosis of Epithelioid and Mixed-Type Malignant Mesothelioma: Ten Years of Clinical Experience in Relation to International Guidelines

Immunohistochemical staining showed positive staining for vimentin, cytokeratin (CK), epithelial membrane antigen (EMA), cluster of differentiation-10 (CD-10), human chorionic gonadotropin, and carcinoembryonic antigen, confirming cervical metastasis of RCC.

Cervical Metastasis from Renal Cell Carcinoma

Such analyses show concurrent presence of malignant epithelial and homologous sarcomatoid spindle cell components by co-expression of cytokeratin, epithelial membrane antigen, and vimentin to various degrees.

Spindle cell carcinoma of nose--a case report

Immunohistochemistry revealed tumour cells diffusely positive for CK AE1/AE3 (pancytokeratin) and focally positive for PLAP (Placental Alkaline Phosphatase) (Figure-2) and EMA (Epithelial Membrane Antigen).

Yolk sac tumour arising in mature teratoma in the parapharyngeal space

The neoplastic cells are usually immunoreactive with vimentin, keratin, epithelial membrane antigen, and S-100 protein.

Chordoma