1.Harm of HER2-positive breast cancer? HER2-positive breast cancer is known as the most dangerous type of breast cancer. 20%-30% of tumors in breast cancer are HER2-positive, compared to normal breast cancer, too much HER2 will stimulate the cancer cells to grow and divide faster, making them more aggressive, which means the tumor progresses faster and is more likely to metastasize and recur, and patients with HER2-positive breast cancer may not be sensitive to certain treatments, so their survival is only half of that of HER2-negative patients. Survival period is only half of HER2 negative patients. 2.Why HER2 test? HER2 test is an important test in breast cancer molecular typing, which can predict whether the prognosis of breast cancer is good or not, and whether it is prone to recurrence, metastasis, or deterioration, etc. Only when the HER2 status is clear can treatment plan be made. If HER2 test is positive, anti-HER2 targeted therapy (Herceptin) is needed. 3.What is the method to clarify HER2 status? There are two methods of HER2 detection: 1. Immunohistochemistry (IHC) 2. In situ hybridization (ISH) HER2 positive: 1. IHC test 3+ 2. ISH test result is positive (IHC 2+ should be re-tested by ISH) If your immunohistochemistry is 2+ (Cerb-2 is 2+), please promptly communicate with your doctor for FISH or ISH test to clarify HER2 status. If you are a patient with recurrent metastasis, please promptly communicate with your doctor to perform HER2 testing again for recurrent metastasis to clarify HER2 status once again. 4. What is the standardized treatment plan for HER2-positive patients? Treatment with Herceptin (trastuzumab), a targeted drug against HER2-positive, is the basic treatment drug for HER2-positive breast cancer patients and provides the greatest possibility of cure. Adding Herceptin to chemotherapy can further reduce the risk of recurrence and metastasis by 52%, reduce the risk of death by 39%, and provide a chance of cure in 80% of patients. For patients with early HER2-positive disease, the standard course of therapy with Herceptin is one year. For HER2-positive patients with recurrent metastases, the standard course of Herceptin treatment is until disease progression (no change in efficacy, always use). 5. Why use Herceptin? Herceptin (trastuzumab), an anti-HER2 molecular targeting drug, uses HER2 molecules on the surface of cancer cells as the “target” to inhibit tumor cell proliferation by blocking the HER2 signaling pathway. The invention of Herceptin is a milestone in the history of breast cancer treatment and has been recognized by domestic and foreign experts as the basic drug and standard treatment for HER2-positive breast cancer.