S-100 expression is seen in cartilaginous tumors, myoepithelial tumors, Schwann cells and neural tumors, Langerhans cell proliferations, benign and malignant melanocytes, clear cell sarcoma, and some carcinomas (particularly of the breast). S-100 staining occurs both in the nucleus and cytoplasm.

What stains positive for S100?

Sex cord–stromal tumors, including granulosa cell tumors,⁴²¹ Sertoli cell tumors,⁴²² and tumors in the fibroma-thecoma group, occasionally show positive staining for S-100.

What does S100 negative mean?

S-100 protein is considered a characteristic immunohistochemical marker for all nevomelanocytic lesions, in which it is expected to be present consistently. We reviewed 17 cases of malignant melanomas that previously tested negative for S-100 protein.

What is S100 immunohistochemistry?

Marker of schwann cells and melanocytes; useful for evaluating nerve sheath tumors and melanoma.

What is S100 test?

High levels of S100A8/A9 (alias: calprotectin) and S100A12 (alias: Calgranulin C, EN-RAGE) are characteristic of active systemic juvenile idiopathic arthritis (sJIA) and may distinguish sJIA from other febrile illnesses, including systemic infection, various forms of leukemia, and Kawasaki disease.

What do S100 proteins do?

The S100 proteins, a family of calcium-binding cytosolic proteins, have a broad range of intracellular and extracellular functions through regulating calcium balance, cell apoptosis, migration, proliferation, differentiation, energy metabolism, and inflammation.

Are histiocytes positive for S100?

Cessation of smoking has been found to lead to complete or partial remission of the disease. Langerhans cells, being histiocytes, are positive for histiocyte marker CD68 but are also characteristically positive for both CD1a and S100.

Which malignant melanoma subtype is S-100 positive only?

S100 negative melanomas are rare. S100P is positive in all subtypes of melanoma, including desmoplastic melanoma, for the diagnosis of which it remains an important reagent. Along with Sox10 and nerve growth factor receptor (NGFR), it is the most sensitive marker to visualize invasive melanoma (Fig.

How does antibody staining work?

Immunohistochemical staining is accomplished with antibodies that recognize the target antigen. Since antibodies are highly specific, the antibody will bind only to the antigen of interest in the tissue section. The antibody-antigen interaction is then visualized using different detection systems.

Is melanoma S-100 negative?

Although S-100 is the least specific marker, it is of great practical importance because it exhibits the highest sensitivity. The S-100 negative melanomas occur in up to 4% of cases and present a diagnostic pitfall as was demonstrated by this case.

What is cytokeratin a marker for?

Cytokeratin 5/6 is a positive marker for malignant pleural mesothelioma, found in more than three-fourths of cases. It is also found in certain types of lung cancers and breast cancers. Pathologists use cytokeratin 5/6 to stain cancer tissue samples.

What is a granular cell tumor?

Listen to pronunciation. (GRAN-yoo-lur sel TOO-mer) A rare type of soft tissue tumor that usually begins in Schwann cells (cells that hold nerve cells in place). It can occur anywhere in the body, but it usually occurs in or under the skin of the head and neck (especially the mouth or tongue).

What does CD68 positive mean?

Fibrolamellar carcinomas are positive for CD68. Increased numbers of CD68-positive tumor macrophages indicate an adverse overall outcome in Hodgkin lymphoma. Significant co-localization of CD36 receptor with cells of the macrophage lineage, such as CD68 positive cells.

Is there a tumor marker for melanoma?

Two tumor markers are usually used for the monitoring of patients with melanoma, the proteins S100 and melanoma-inhibitory activity (MIA). S100 represents a family of calcium-binding proteins differentially expressed in a large variety of tissues (14).

What does HMB 45 stain?

HMB-45 is a widely used immunohistochemical stain for detection of primary as well as metastatic melanoma (1). Presumably, this method uses monoclonal antibodies to a glycoprotein that is present in premelanosomes (11).

What is vimentin stain?

Vimentin is an intermediate filament protein widely expressed in mesenchymal tumors as well as various types of nonmesenchymal tumors. It is also believed to be a marker for epithelial to mesenchymal transition.