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TdT pin



Methodology: IHC

Clinical Significance:
Identifies: Terminal deoxynucleotidyltransferase, a specialized DNA polymerase expressed in immature, pre-B, pre-T lymphoid cells, and also the majority of precursor B- and T-lymphoblastic leukemias/lymphomas. TdT is aberrantly expressed in a small subset of acute myeloid leukemias. Subcellular Localization: Nuclear


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