Alternate Test Names:
von Willebrand Factor

Methodology: IHC

Clinical Significance:
Identifies: von Willebrand factor (often erroneously referred to as "Factor VIII") is synthesized by endothelial cells and stored in the Weibel-Palade granules. von Willebrand factor can be employed as a marker of vascular neoplasms as well as a marker of megakaryocytic differentiation.

Subcellular Localization: Cytoplasmic

Organ:

Disease State: Acute Myeloid Leukemia (AML) / Myeloid Sarcoma, Spindle Cell Tumors / Sarcoma Subtyping

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