HER2 amplification detection by FISH (fluorescence in situ hybridization) is a diagnostic test used to detect HER2 gene amplification in breast cancer tissue samples. The test is used to determine if a patient with breast cancer is a candidate for targeted therapy with drugs such as trastuzumab.
When this test is required
This test is used to determine whether a breast cancer patient is a candidate for targeted therapy with drugs that specifically target HER2, such as trastuzumab (Herceptin) or lapatinib (Tykerb). These drugs have been shown to improve outcomes for patients with HER2-positive breast cancer.
What the Test Detects
HER2 Amplification Detection by FISH (Fluorescence In Situ Hybridization) is a laboratory test used to identify the number of copies of the HER2 (Human Epidermal Growth Factor Receptor 2) gene in a sample of tissue, usually from a breast cancer biopsy. HER2 is a protein that plays a role in cell growth and division. Overexpression or amplification of HER2 is found in some breast cancers and is associated with a more aggressive disease and a higher risk of recurrence.
Preparation for the Test
There is no specific preparation required for the test. However, patients should inform their doctor of any medications they are taking, including any herbal supplements or over-the-counter medications, as some drugs can interfere with test results.
Sample Requirements
To perform the test, a tissue sample is required from the patient’s breast cancer biopsy. The tissue sample is sent to a laboratory where it is processed and analyzed using FISH technology.
Additional Notes
HER2 Amplification Detection by FISH is typically requested as part of the diagnostic workup for breast cancer patients, usually after a biopsy has confirmed the presence of cancer cells. It may also be ordered for patients with recurrent or metastatic breast cancer.
