Human Epidermal Growth Factor Receptor 2 (HER2) Testing via Unifraction Intensity Measurement in Breast Cancer Specimen (Tissue)
This test measures the amount of HER2 protein in a sample of breast tissue to help determine if a tumor may respond to targeted therapies like trastuzumab (Herceptin).
["HER2 testing helps guide treatment decisions for breast cancer by assessing tumor biology."]
Key facts at a glance
- LOINC
- 85328-3
- Short code
- HER2 unif int NFr Br ca spec ImStn
- Synonyms
- HER2 unif int NFr Br ca spec ImStn
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- immune-stain
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order this test if you have a breast cancer diagnosis, particularly if your tumor is suspected to be HER2-positive. HER2 testing helps determine whether your cancer may benefit from specific treatments that target the HER2 protein.
How Is the Sample Collected?
A small sample of your breast tumor tissue is collected during surgery or a biopsy. This sample is then analyzed in a lab to measure HER2 protein levels.
What Does the Test Result Mean?
Results are typically reported as a ratio or intensity score (e.g., 0, 1+, 2+, or 3+). A score of 3+ indicates a high level of HER2 protein, which may suggest a response to HER2-targeted therapies. Your doctor will discuss the result in the context of your overall cancer treatment plan.
What Are Possible Outcomes?
Possible outcomes include HER2-negative (not likely to respond to HER2-targeted drugs) or HER2-positive (may respond to targeted therapies like trastuzumab). Some tumors may also require additional testing (e.g., fluorescence in situ hybridization, or FISH) for confirmation.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: HER2 Testing Plays a Critical Role in Personalized Cancer Treatment. HER2-positive breast cancers are more aggressive and may grow faster than HER2-negative cancers. Testing helps identify patients who could benefit from targeted therapies that specifically block the HER2 protein, potentially improving outcomes and reducing side effects from broader treatments. Your doctor will use the test result to tailor your treatment plan, including options like chemotherapy, hormonal therapy, or HER2-targeted drugs.
Short name
HER2 Testing (Breast Tissue)
Frequently asked questions
Will this test affect my treatment choices?
How long does it take to get the results?
Can I eat or drink before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy