FAQs
What is HER-2/neu?
HER-2/neu is also referred to as HER-2 or cerB-2. HER-2 stands for Human Epidermal Growth Factor Receptor 2. The HER-2 gene is one of thousands of genes that comprise every living person's genetic code and is present in the nucleus of all human cells, including breast tissue cells. The HER-2 gene provides the blueprint for the manufacture of the HER-2 protein. This protein, which is attached to the cell membrane, regulates normal cell growth and function.
Abnormally high quantities of the HER-2 gene have been associated with rapid tumor cell growth, resistance to therapy, and shorter disease-free periods and overall survival. Approximately 20-25%, or 1 out of every 4, breast cancers have an abnormally high quantity of the HER-2 gene, and are considered HER-2 positive.
back to top
How common is HER-2 positive breast cancer?
Approximately 20-25%, or 1 out of every 4 women, have HER-2 positive breast cancer.
back to top
Do I need to know my HER-2 status?
Your HER-2 status is an important factor for you and your doctor to understand as you decide on your best treatment options. The NCCN (National Comprehensive Cancer Network) and ASCO (The American Society of Clinical Oncologists) recommend HER-2 assessment for all invasive breast cancers.
While it is recommended at initial diagnosis, HER-2 status can be determined at anytime after initial diagnosis as well. There is discussion within the medical community that HER-2 status should be assessed with each occurrence or recurrence of invasive breast cancer.
back to top
How will knowing my HER-2 status affect my therapy decisions?
Determination of HER-2 status has become an important tool in the routine assessment and management of patients with breast cancer. Abnormally high quantities of the HER-2 gene have been shown to result in more aggressive tumor behavior. HER-2 positive patients may react differently to chemotherapy. Studies have shown HER-2 positive tumors obtain greater benefit from the addition of anthracyclines and from more dose-intensive anthracycline administration than HER-2 negative tumors.
HER-2 amplified tumors may benefit from targeted monoclonal antibody therapies, such as Herceptin® (www.herceptin.com).
back to top
How will my HER-2 status be identified?
The two most widely used technologies are ImmunoHistochemistry (IHC) and Fluorescence in situ Hybridization (FISH). The PathVysion test employs FISH technology to determine HER-2 status.
back to top
Does the type of HER-2 test make a difference?
Yes. The most accurate HER-2 assessment means the most accurate therapy decisions will be made.
The IHC test is a protein-based test that is used to determine the total amount of HER-2 protein receptors on the surface of the cell. To do this, the surface of the cell is "stained" with an antibody. The surface protein measured by IHC can be damaged during preparation of the tissue sample and this may cause variability in outcome. A pathologist must judge the degree of color change in the cell to determine a HER-2 protein measurement level of 0, 1+, 2+, or 3+. Because this test is subjective, the results often are confirmed by performing a FISH test.
The PathVysion® test yields definitive results at the molecular level. PathVysion "highlights" the HER-2 genes inside the cell, making them appear fluorescent so they may be accurately counted. If a patient has an abnormal number of HER-2 genes, she is considered HER-2 positive. If the test shows a normal gene count, the test results are considered HER-2 negative. PathVysion allows the physician or pathologist to literally count the genes, allowing for a more objective assessment of test results and helping to positively identify women who are candidates for HER-2-targeted therapies.
back to top
What if I have already had a biopsy, but don't know if I've been screened for HER-2?
Your HER-2 results can be obtained from your biopsy tissue, at any time, by using the PathVysion test. Because the test measures the HER-2 gene at the stable DNA molecular level, results can be obtained from stored tissue samples. Ask your doctor for more information. Knowing your HER-2 status is important for your treatment decisions.
back to top
