Alternate Test Names:
KP1

Methodology: IHC

Clinical Significance:
Identifies a cytoplasmic/lysozomal-associated protein expressed by normal and neoplastic monocytes/histiocytes, including Langerhans cells. Neoplasms of lymphoid origin are usually negative, although some B cell neoplasms, most frequently small lymphocytic lymphoma and hairy cell leukemia, show weak staining of the cytoplasm, usually in the form of a few scattered granules.

Subcellular Localization: Cytoplasmic

Organ:

Disease State: Acute Myeloid Leukemia (AML) / Myeloid Sarcoma, Langerhans Cell Histiocytosis

CPT Code(s): 88342 or 88341 (reference only; CPTs may vary)

Turnaround Time: Within 1-2 business days of receipt

Schedule: Monday - Friday

Specimen Requirements:
• Formalin-fixed, paraffin-embedded (FFPE) tissue block or cell block - OR -
• 1 unstained slide for each test requested plus 3-4 additional unstained slides cut at 4µm