HLA-DR (MHC class II) pin

IHC

HLA-DR (MHC class II)

Alternate Test Names:
Class II histocompatibility antigen; HLADR

Methodology: IHC

Clinical Significance:
Identifies: HLA-DR (class II histocompatibility antigen). Expressed in lymphomas and leukemias, both myeloid and lymphoid. Examples include acute myeloid leukemias (AML), and chronic myelomonocytic leukemias (CMML). Expression varies in each neoplasm, depending on various factors, including cell maturity and differentiation. HLA-DR has been shown to be consistently expressed in most AMLs of non-M3 (Acute promyelocytic or APL) type, and has been shown to be helpful in differentiating myeloblastic from promyelocytic variants.

Subcellular Localization: Membranous

Organ:

Disease State: Blastic Plasmacytoid Dendritic Cell Neoplasm

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

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