Methodology: IHC

Clinical Significance:
Identifies a subset of carcinomas. Co-analysis of expression of cytokeratin 7 can be helpful in the identification of the primary site of carcinomas presenting at metastatic sites. CK20 is also a marker of Merkel cell tumors, usually displaying a dot-like perinuclear pattern of expression. Subcellular Localization: Cytoplasmic

Organ: Colon & Other GI

Disease State: Carcinomas of Unknown Primary

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