Lab Test

HER2 by Immunohistochemistry (IHC)

HER2, HER2/neu, Gastic Cancer HER2

Department

Advanced Diagnostics

Specimen Collection Criteria

Collect (preferred specimen): Formalin-fixed, paraffin-embedded block with corresponding H&E slide. Tissue should be well fixed and well processed. Tissue must be fixed for a minimum of 6 hours and a maximum of 72 hours in 10% neutral buffered formalin. 

Also acceptable: One H&E slide plus 4 unstained tissue sections cut at 4.0 µm thickness and placed on charged slides. Air dry, do not oven dry. Tissue adherence cannot be guaranteed for sections placed on plain glass slides. Send all slides within 6 weeks of cutting. 

All specimens must be accompanied by a completed requisition containing the patient name, date of birth, collection date, ordering physician, source of specimen, fixation time and cold ischemia time (if known), and a pathology report. 

Physician Office/Draw Specimen Preparation

Maintain paraffin-embedded tissue or slides at room temperature (20-25°C or 68-77°F) until transport. 

Preparation for Courier Transport

Transport: Paraffin-embedded tissue or slides, at room temperature (20-26°C or 68-78.8°F). 

Rejection Criteria

  • Tissue in fixatives other than 10% formalin.
  • Improper labeling, inadequate information.

Inpatient Specimen Preparation

Please refer to Surgical Specimen, Routine in the Beaumont Laboratory Test Directory.

In-Lab Processing

Maintain specimens at room temperature (20-26°C or 68-78.8°F) until testing. 

Storage

Specimen Stability for Testing:

Paraffin-Embedded Tissue
Paraffin-Embedded Tissue Room Temperature (20-26°C or 68-78.8°F): Indefinitely 
Refrigerated (2-8°C or 36-46°F): Unacceptable 
Frozen (-20°C/-4°F or below): Unacceptable 

Tissue Section on Glass Slides
Room Temperature (20-26°C or 68-78.8°F): 6 weeks 
Refrigerated (2-8°C or 36-46°F): Unacceptable 
Frozen (-20°C/-4°F or below): Unacceptable 

Specimen Storage in Department Prior to Disposal:
Room Temperature (20-26°C or 68-78.8°F): 7 days 

Laboratory

Dearborn Anatomic Pathology – Histology E225 

Royal Oak Anatomic Pathology – Advanced Diagnostics Laboratory.

Performed

Dearborn
Daily. Results available in 2-3 business days.

Royal Oak
Daily. Results available in 7 business days.

Reference Range

HER2 over-expression: This assay is intended to be performed on formalin-fixed tissue. The effects of other types of fixatives on the assay results have not been established.

IHC Intensity Result:

0: Negative
1+: Negative
2+: Equivocal
3+: Positive

This assay is performed in concordance with CAP/ASCO (2013) criteria on invasive tumor only. The kit used in the staining has been FDA approved for breast cancer only. Its use in other types of cancer should be considered only for investigational or research use. The results of the test can be altered/affected by variables beyond our laboratory's control. (e.g. fixatives other than formalin, fixation times other than that recommended in CAP/ASCO guidelines).

Test Methodology

Dearborn
Immunoperoxidase staining and detection of HER2 is performed on formalin-fixed, paraffin-embedded tissue sections using polymer-based detection system. 4µm tissue sections are deparaffinized, subjected to heat-induced antigen retrieval and then sequentially incubated with Anti-Her 2/neu Rabbit Monocolonal (Ventana) and followed by a multimer detection reagent.  Sections are subsequently treated with the chromogen 3, 3’-diaminobenzidine and the substrate horseradish peroxidase to produce a brown membranous staining pattern. Sections are counterstained with hematoxylin. 

Royal Oak
Immunoperoxidase staining and detection of HER2 is performed on formalin-fixed, paraffin-embedded tissue sections using polymer-based detection system. 4µm tissue sections are deparaffinized, subjected to heat-induced antigen retrieval and then sequentially incubated with anti-receptor polyclonal antibody (HercepTest, Dako Inc.) and followed by a polymer detection reagent. Sections are subsequently treated with the chromogen 3, 3’-diaminobenzidine and the substrate horseradish peroxidase to produce a brown membranous staining pattern. Sections are counterstained with hematoxylin.

Interpretation

Dearborn
Immunoperoxidase-stained slides are examined by a pathologist who will provide an interpretive report. Results are reported as negative (0, 1+), equivocal (2+), and positive (3+) according to the interpretation guidelines in the FDA-approved Pathway anti-Her2/neu (4B5) Rabbit Monoclonal Primary Antibody (Ventana).

Royal Oak
Immunoperoxidase-stained slides are examined by a pathologist who will provide an interpretive report. Results are reported as negative (0, 1+), equivocal (2+), and positive (3+) according to the interpretation guidelines in the FDA-approved HercepTest. (Dako Inc.).

Clinical Utility

HER2 amplification or overexpression in breast, endometrial, ovarian, and other epithelial carcinomas has been associated with shorter disease-free interval and shorter overall survival.

Women who have tumors that overexpress HER2 are most likely to be responsive to monoclonal antibody therapy directed against this target. Approximately 20-25% of patients with gastric cancer have tumors which are HER2 positive. In this group, molecularly targeted therapy with trastuzumab added to cytotoxic chemotherapy improves overall survival and progression-free survival. 

Reference

  1. Wolff, AC, Hammond, MEH, Hicks, DG et al. American Society of Clinical Oncology / College of American Pathologists Guideline Recommendations for Human Epidermal Growth Factor Receptor 2 Testing in Breast Cancer. J Clin Oncol 2013 Nov 1; 31(31) 3997-4013. 

CPT Codes

Technical and Professional CPT: 88360

Contacts

Last Updated

8/15/2022

Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.