Targeted therapies for breast cancer

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Targeted therapies work by blocking the growth and spread of cancer by interfering with the biology of the cancer cells. 

When are targeted therapies used?

  • For women who have HER2-positive breast cancer. The targeted drugs block the receptors on the cells, so that HER2 proteins can’t attach to the cells and help them to grow. The drugs also help the immune system to target and kill the cancer cells. 
  • For some types of metastatic breast cancer.

The drugs most commonly used for breast cancer are monoclonal antibodies. An example is trastuzumab (Herceptin®). This drug is only used for HER2 positive breast cancer.

Your cancer can be tested for HER2 levels at the time of your surgery or from a biopsy.

How are targeted therapies given?

You may have targeted therapy before or after surgery, or both. Usually the drugs are given into a vein through a drip or as an injection. Other drugs may be given as a tablet. 

You may have a combination of different drugs. For example, you may have a targeted therapy drug and chemotherapy.

Side-effects of targeted therapies

These drugs only target the cancer cells and leave normal cells alone. This means you usually get fewer side-effects than with chemotherapy.

Side-effects depend on the drugs being used and vary from person to person. Common side-effects include flu-like symptoms such as a headache, high temperature (fever) and chills, or feeling sick. You may also get diarrhoea. 

Some drugs affect the way the heart works. If you have any heart problems like heart disease or uncontrolled high blood pressure you may not be suitable for a drug like trastuzumab.

Your doctor and nurse will explain your treatment in more detail and tell you about any likely side-effects. Tell your doctor or nurse if you don’t feel well or if any symptoms are troubling you.

For more information on targeted therapies and their side-effects, call our Cancer Nurseline on 1800 200 700 or visit a Daffodil Centre. Read more about coping with side-effects.

For more information

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