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CD99 pin



Methodology: IHC

Clinical Significance:
CD99 has historically been used as a marker of PNET/Ewing sarcoma, as well as a subset of spindle cell tumors, including synovial sarcoma and solitary fibrous tumor, although there are other more specific markers now available for these latter tumors. Use of CD99 is not recommended; please contact one of our pathologists for alternative markers. Subcellular Localization: Membranous


Disease State: Small, Blue, Round Cell Tumors

CPT Code(s): 88342 or 88341. The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.

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