ERBB2 (HER2/neu) (HercepTest) by Immunohistochemistry, Tissue with Reflex to FISH if 2+
Also known as: HERCEP2IP
Use
The test aids in predicting the response to HER2-directed therapy in patients with breast carcinoma or gastroesophageal adenocarcinoma. It evaluates the expression level of HER2/neu proteins in the tumor tissue, helping to guide treatment decisions. The presence of HER2 overexpression detected by immunohistochemistry followed by reflex to FISH for equivocal results provides insight into the potential efficacy of targeted therapies such as trastuzumab.
Special Instructions
Refer to the ARUP Immunohistochemistry Stain Offerings brochure for more details. Submit tissue blocks or unstained slides along with a pathology report detailing the tissue source and tumor origin. Document the time from tissue acquisition to fixation and submit it with the order.
Limitations
Tissues fixed for outside the range of 6-72 hours in 10% neutral buffered formalin may produce unreliable results. Decalcified specimens should be interpreted with caution due to the potential for false-negative results. The interpretation is limited to breast and gastric cancers per FDA approval. The presence of tumor heterogeneity may affect test accuracy.
FDA ApprovedNew York Approved
Methodology
Immunoassay (IHC)
Biomarkers
LOINC Codes
- 18474-7
- 94736-6
- 31208-2
Result Turnaround Time
1-5 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (FFPE)
Volume
Not provided
Minimum Volume
6 slides
Collection Instructions
Formalin fix (10 percent neutral buffered formalin) and paraffin embed tissue within 30 minutes of removal from patient. Use ARUP supply #47808 for transport.
Storage Instructions
Transport at room temperature or refrigerated; ship in a cooled container during summer months.
Causes for Rejection
Paraffin block with no tumor tissue remaining. Delay in fixation for more than one hour. Usage of other fixatives besides 10% neutral buffered formalin. Tissue under-fixed or over-fixed outside the specified 6-72 hours range.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Indefinitely |
| Refrigerated | Indefinitely |
| Frozen | Unacceptable |