Alternate Test Names:
4B5

Methodology: IHC

Clinical Significance:
Identifies: The HER2 gene product, which is overexpressed, almost always as a consequence of HER2 gene amplification, in a subset of breast cancers, gastric adenocarcinomas, and other tumors. It is a prognostic and predictive marker, and the target of trastuzumab and other HER2 targeted therapies.

Subcellular Localization: Membranous

Organ: Breast, Colon & Other GI

Disease State: Breast Cancer

CPT Code(s): 88360 (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