Identifies a cytoplasmic/lysozomal-associated protein expressed by normal and neoplastic monocytes/histiocytes, including Langerhans cells. It is useful for identifying macrophages and stains them in a wide variety of human tissues, including Kupffer cells and macrophages in the red pulp of the spleen, lamina propria of the gut, lung alveoli, and bone marrow. Neoplasms of lymphoid origin are usually negative, although some B cell neoplasms, most often small lymphocytic lymphoma and hairy cell leukemia, show weak staining of the cytoplasm. Reacts with myeloid precursors and peripheral blood granulocytes and shows strong staining of chronic and acute myeloid leukemia and also reacts with true histiocytic neoplasia, as well as granular cell tumors and some cases of melanoma, renal cell carcinoma, and pleomorphic sarcoma.

Turnaround Time
24 hrs
Specimen Requirements

A formalin-fixed, paraffin-embedded (FFPE) tissue block is preferred specimen typeorOne (1) unbaked, unstained slide for H&E staining (required) and two to three (2-3) positively charged unstained slides (all cut at 4-5 microns) for each test/antibody orderedBlock and slide identifiers should be clearly written and match exactly with the specimen ID and specimen labeling as noted on the requisition.

Storage and Transportation

Use cold pack for transport. Make sure cold pack is not in direct contact with specimen.

CPT Codes
88342 x 1 or 88341 x 1