- Herceptin is used to treat breast cancer that is HER2+. HER2 stands for "Human Epidermal growth factor Receptor 2," a protein that causes cancer cells to multiply quickly when the body produces too much of it. HER2+ cancers may also be called HER2/neu-positive or HER2 overexpressing. Herceptin is not useful for treating other types of breast cancer because it only attaches to HER2 proteins. It may then work by slowing the growth and reproduction of the HER2+ cancer cells and by encouraging the immune system to attack and destroy the breast cancer cells.
- Herceptin is an adjuvant treatment, meaning that is it used in conjunction with other cancer treatments like chemotherapy. Depending on the individual case, doctors may choose to administer Herceptin concurrently with chemotherapy or hormone therapy. Or it may be administered after other treatments, such as surgery and radiation, are complete.
- Herceptin is administered by infusion through an IV or implanted catheter, such as a port. Infusions typically take about 30 to 90 minutes each. Herceptin infusions may be weekly or once every three weeks, depending on the treatment schedule and the other drugs Herceptin is used in combination with. Most patients stay on Herceptin for one year or longer.
- HER2+ tumors are generally harder to treat and are more likely to return versus other types of breast cancer. This is because the HER2 protein causes the cancer cells to grow and multiply quickly. In clinical trials, women who received Herceptin had a 33- to 52-percent lower chance of having a breast cancer recurrence than those who only received chemotherapy. Preventing the return of breast cancer may help improve long-term survival rates for people with HER2+ cancer.
- The side effects of Herceptin depend upon the individual's reaction to it and the types of chemotherapy drugs with which it is used in conjunction. Common side effects of Herceptin include gastrointestinal symptoms, such as nausea, vomiting and diarrhea, as well as fatigue, shortness of breath and decreased red blood cell counts. Some patients may experience fever and increased susceptibility to infections due to a drop in white blood cell counts. In rare cases, patients may experience severe infusion reactions to Herceptin, including heart and lung problems. Patients who take Herceptin for an extended period of time generally need to undergo periodic evaluations to make sure the drug is not weakening the heart. Since Herceptin is not a chemotherapy, it typically does not cause hair loss. However, other drugs taken at the same time as Herceptin might cause additional side effects.
