- Guide to Breast Cancer
- Take the Breast Cancer Quiz
- Young Women & Breast Cancer
- Breast Cancer FAQs
- Patient Comments: Breast Cancer - Symptoms and Signs
- Patient Comments: Breast Cancer - Stages
- Patient Comments: Breast Cancer - Type
- Patient Comments: Breast Cancer - Treatment
- Patient Comments: Breast Cancer - Survival Rate
- Patient Comments: Breast Cancer - Diagnosis
- Find a local Oncologist in your town
- Breast cancer facts
- What is breast cancer?
- What are the statistics on male breast cancer?
- What are the different types of breast cancer? Where does breast cancer come from?
- What causes breast cancer?
- What are breast cancer risk factors? How do you get breast cancer?
- What about antiperspirants or deodorants as causes of breast cancer?
- What are breast cancer symptoms and signs?
- What tests do physicians use to diagnose breast cancer?
- What is HER2-positive breast cancer?
- What tests detect HER2?
- Do symptoms and signs of HER2-positive breast cancer differ from those of HER2-negative breast cancer?
- What are therapies for HER2-positive breast cancers?
- How are breast cancer stages determined?
- What are breast cancer treatments?
- What are breast cancer survival rates by stage? What is the prognosis of breast cancer?
- Is it possible to prevent breast cancer?
- What research is being done on breast cancer? Is it worthwhile to participate in a breast cancer clinical trial?
- I may have breast cancer. What questions should I ask my doctor?
- Is the doctor sure I have breast cancer?
- What type of breast cancer do I have?
- What difference does a precise breast cancer diagnosis make?
- What has been done to exclude cancer in other areas of the same breast or in my other breast?
- What type of medical team do I need for the most accurate breast cancer diagnosis?
- Is my family history relevant to my breast cancer diagnosis?
- What other studies should be done on my breast tissue biopsy?
- How urgent is it that I make decisions and begin breast cancer treatment?
- Should I stop taking hormone replacement therapy (HRT) after a breast cancer diagnosis?
- Even though my breast tumor does not have hormone receptors, should I take tamoxifen to reduce the risk of a new tumor?
- I have a ductal carcinoma in situ (DCIS), a type of localized cancer. Why have I been advised to have a mastectomy when other women with invasive breast cancer have lumpectomies?
- Should I start chemotherapy before surgery for breast cancer?
- If I am advised to have a mastectomy, what are the risks and benefits of immediate breast reconstruction?
- Should breast cancer patients have their lymph nodes removed?
- What is a sentinel lymph node biopsy, and what are its benefits and risks?
- Are there any other questions I should ask my doctor about breast cancer?
Quick GuideBreast Cancer Diagnosis and Treatment
What is HER2-positive breast cancer?
For about 20% of women with breast cancer, the cancer cells test positive for HER2. HER2 is a growth-promoting protein located on the surface of some cancer cells. HER2-positive breast cancers tend to grow more rapidly and spread more aggressively.
What tests detect HER2?
All patients with invasive breast cancer should have their tumor cells tested for HER2.
There are four tests for HER2. The interpretation of the tests should be discussed with your health-care team. Either immunohistochemistry (IHC) or in-situ hybridization (ISH) testing may be used.
IHC test: This tests shows if there is too much HER2 protein in the cancer cells and is graded 0 to 3.
FISH test: This test evaluates if there are too many copies of the HER2 gene in the cancer cells. This test is either positive or negative.
SPoT-Light HER2 CISH test: This test also evaluates if there are too many copies of the HER2 gene in the cancer cells and is reported as positive or negative.
Inform HER2 Dual ISH test: This test also evaluates if there are too many copies of the HER2 gene in the cancer cells and is reported as positive or negative.
Do symptoms and signs of HER2-positive breast cancer differ from those of HER2-negative breast cancer?
The signs and symptoms for HER2-positive breast cancers are the same as for HER2-negative breast cancers, except for the fact that HER2-positive cancers grow faster and are more likely to spread.
What are therapies for HER2-positive breast cancers?
All therapy needs to be evaluated by your health-care team and guided in response to all test results available and the specific circumstances of your cancer.
There are targeted therapies for HER2-positive breast cancers; a number of drugs are available to target this protein:
- Trastuzumab (Herceptin): a monoclonal antibody given by itself or with chemotherapy to treat HER2-positive breast cancers
- Pertuzumab (Perjeta): another monoclonal antibody that targets HER2-positive cancers
- Ado-trastuzumab emtansine or TDM-1 (Kadcyla): a monoclonal antibody that is attached to a chemotherapy drug
- Lapatinib (Tykerb): a kinase inhibitor usually used in adjunct with chemotherapy or hormone therapy