HER2 is an aggressive form of breast cancer that grows and spreads rapidly. About one in five women with breast cancer have HER2-positive breast cancer or protein human epidermal growth factor receptor2.
Indications
For HER2-positive breast cancer, Herceptin is used as an adjuvant chemotherapy treatment, meaning that it follows primary treatment, which is usually surgery. It’s considered effective for early-stage HER2-positive breast cancer regardless of whether it has spread to the lymph nodes.
A long-term follow-up study published in 2017 showed that one year of treatment with this drug significantly improved disease-free survival.
Herceptin also is approved to treat metastatic breast cancer in two ways—in combination with the chemotherapy medication paclitaxel or alone for people who have already received chemotherapy for metastatic breast cancer.
How It Works
The HER2 gene generates a protein receptor on the surface of a tumor cell. This receptor signals the cell to divide and multiply. When there’s too much HER2 in breast cancer tissue, cell division ramps up.
Herceptin attaches to the HER2 receptors and blocks that growth signal, preventing more cell division and slowing the progression of cancer. The drug only hunts down those cancer cells that have HER2/neu receptors on their outer surface.
Herceptin is part of a class of drugs called biologic therapies.
Administration
Herceptin is a pale white or yellow fluid that’s given via a chemotherapy infusion. Your first dose will be given slowly in a 90-minute session to see how well you tolerate the drug and to watch for an allergic reaction.
If you do well with it, your following infusions can be given in 30-minute sessions.
Side Effects
Some patients receiving Herceptin for breast cancer have reported the following side effects:
FeverFeeling sick to your stomach (nausea)Throwing up (vomiting)Infusion-site reactionsDiarrheaInfectionsIncreased coughHeadacheFeeling tiredShortness of breathRashLow white and red blood cell countsMuscle pain
Some patients receiving Herceptin for metastatic stomach cancer had the following additional side effects, which should also be considered:
Extreme shortness of breathWheezingSwelling of throat or lipsHives
Swelling of the mouth liningWeight lossUpper respiratory tract infectionsLow platelet countsSwelling of the mucous membranesSwelling of the nose and throatChange in sense of taste
These symptoms usually appear within 24 hours of the infusion.
Risks
Herceptin comes with a few risks to consider. First, it can cause heart problems and congestive heart failure. Your left ventricular function needs to be checked immediately before starting Herceptin, at regular time intervals while on it (the package insert recommendation is every three months), and after you finish treatment.
The risk of heart problems increases if you are being treated with Adriamycin and Cytoxan as well as Herceptin.
Most oncologists recommend that you refrain from using alcohol and tobacco during Herceptin treatment. Caffeine should also be avoided, as it causes drying of your tissues, which only adds to the drying effects already caused by your chemo drugs.
Tell your healthcare team if you are using tobacco, alcohol, or recreational drugs, and, if necessary, ask for help quitting.
Self-Care
Taking good care of yourself, in general, is important to your health and well-being. During treatment, you should be sure to save time for self-care:
Stay well-hydrated by drinking two or three quarts of fluids every 24 hours. If needed, take your anti-nausea medications as directed. If you’re dizzy or drowsy, take it easy until these symptoms subside. If you have flu-like symptoms, stay warm and drink lots of fluids (sports drinks can help). Aches and pains may be relieved with acetaminophen or ibuprofen, but check with your healthcare provider first. Rest as much as you can. Eat a good, nutritious diet.
