Sign in →

Test Code HER2I HER2 Immunostain, Technical Component Only


Ordering Guidance


This test provides qualitative results only. For semiquantitative assessment of HER2 as a predictive or prognostic marker in the setting of breast cancer, order HERBA / HER2, Breast, Quantitative Immunohistochemistry, Automated with HER2 FISH Reflex or in the setting of gastric esophageal tissues, order HERGM / HER2, Gastric/Esophageal, Semi-Quantitative Immunohistochemistry, Manual and return Mayo-stained tech only HER2 slide along with hematoxylin and eosin-stained slide, or block and 2 unstained slides.

 

This test includes only technical performance of the stain (no pathologist interpretation is performed). If diagnostic consultation by a pathologist is required order PATHC / Pathology Consultation.



Shipping Instructions


Attach the green pathology address label and the pink Immunostain Technical Only label included in the kit to the outside of the transport container.



Specimen Required


Specimen Type: Tissue

Supplies: Immunostain Technical Only Envelope (T693)

Container/Tube: Immunostain Technical Only Envelope

Preferred:

-Formalin-fixed, paraffin-embedded tissue block

OR

-2 Unstained, positively charged glass slides (25- x 75- x 1-mm) per test ordered; sections 4-microns thick

Acceptable: None


Forms

If not ordering electronically, complete, print, and send a Immunohistochemical (IHC)/In Situ Hybridization (ISH) Stains Request (T763) with the specimen.

Useful For

Identification of HER2 protein overexpression in formalin-fixed, paraffin-embedded tissue sections

Reflex Tests

Test ID Reporting Name Available Separately Always Performed
IHTOI IHC Initial, Tech Only No No
IHTOA IHC Additional, Tech Only No No

Testing Algorithm

For the initial technical component only immunohistochemical (IHC) stain performed, the appropriate bill-only test ID will be reflexed and charged (IHTOI). For each additional technical component only IHC stain performed, an additional bill-only test ID will be reflexed and charged (IHTOA).

Method Name

Immunohistochemistry (IHC)

Reporting Name

HER2 IHC, Tech Only

Specimen Type

TECHONLY

Specimen Stability Information

Specimen Type Temperature Time Special Container
TECHONLY Ambient (preferred)
  Refrigerated 

Reject Due To

Wet/frozen tissue
Cytology smears
Nonformalin fixed tissue
Nonparaffin embedded tissue
Noncharged slides
ProbeOn slides
Snowcoat slides
Reject

Clinical Information

The human HER2 gene (also known as ERBB2 or NEU) encodes a protein often referred to as HER2 protein or P185(HER2). The HER2 protein is a membrane receptor tyrosine kinase with homology to the epidermal growth factor receptor (EGFR or HER1). The HER2 protein is a normal component expressed by a variety of epithelial cell types.

Interpretation

This test does not include pathologist interpretation, only technical performance of the stain. If interpretation is required order, PATHC / Pathology Consultation for a full diagnostic evaluation or second opinion of the case.

 

The positive and negative controls are verified as showing appropriate immunoreactivity and documentation is retained at Mayo Clinic Rochester. If a control tissue is not included on the slide, a scanned image of the relevant quality control tissue is available upon request; contact 855-516-8404.

 

Interpretation of this test should be performed in the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.

Cautions

Age of a cut paraffin section can affect immunoreactivity. Stability thresholds vary widely among published literature and are antigen dependent. Best practice is for paraffin sections to be cut within 6 weeks.

 

The charge of glass slides can be affected by environmental factors and subsequently may alter slide staining. Sending unsuitable glass slides can result in inconsistent staining due to poor slide surface chemistry.

 

Best practices for storage of positively charged slides:

-Minimize time slides are stored after being unpackaged

-Limit exposure to high humidity and heat

-Minimize exposure to plastics

Method Description

Immunohistochemistry on sections of paraffin-embedded tissue.(Unpublished Mayo method)

Day(s) Performed

Monday through Friday

Report Available

1 to 3 days

Specimen Retention Time

Until staining is complete.

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

88342-TC, primary

88341-TC, if additional IHC

LOINC Code Information

Test ID Test Order Name Order LOINC Value
HER2I HER2 IHC, Tech Only Order only;no result

 

Result ID Test Result Name Result LOINC Value
70770 HER2 IHC, Tech Only Bill only; no result