Targeted therapies attack cancer cells directly

Targeted therapies attack cancer cells directly. They do not usually affect healthy tissue and normally cause less side effects than other treatments such as chemotherapy. Trastuzumab (also known as Herceptin) is a targeted treatment that can reduce the chance of your breast cancer coming back if it is HER2 positive.

Will I be offered trastuzumab (Herceptin)?

Trastuzumab targets breast cancers that have high levels of a protein called HER2. These breast cancers are known as HER2 positive and account for around one in five breast cancers. You will only be offered treatment with trastuzumab if your cancer is HER2 positive. You should have receptor tests to determine this before your treatment begins.

Trastuzumab can cause heart problems and it may not be offered to you if you have an existing heart condition. You will have a heart scan before treatment to determine if trastuzumab is right for you. If it is not suitable, your breast care team will discuss other treatment options with you.

How is trastuzumab given?

Trastuzumab is normally given once every three weeks for a year, as an injection under the skin or through a drip.

You can be given trastuzumab before or after surgery. If your trastuzumab treatment starts after surgery (known as adjuvant treatment) it will be given alongside chemotherapy or after chemotherapy.

If you are given trastuzumab before surgery (known as neoadjuvant treatment) it will be given alongside chemotherapy. 

Depending on your type of breast cancer, this may be combined with another targeted therapy called pertuzumab (also known as Perjeta). Your breast care team will let you know if pertuzumab is suitable for you.

Depending on your type of breast cancer, it may be beneficial to combine this with another targeted therapy called pertuzumab (also known as Perjeta). Pertuzumab is not routinely available on the NHS in Northern Ireland, but your oncologist can submit a special Individual Funding Request to prescribe it if they think it is suitable for you.

What are the side effects of trastuzumab?

As with all cancer treatments, you may experience some side effects when taking trastuzumab. Common side effects include flu-like symptoms, diarrhoea, and nausea. Some women experience an allergic reaction to the treatment, although this is rare. A member of your breast care team will monitor you during treatment and help you manage any side effects.

Treatment with trastuzumab can also cause heart problems. Your breast care team will monitor you heart function before and throughout your treatment, and your treatment will be suspended if there is any sign of a heart problem developing.

Because trastuzumab is usually given alongside chemotherapy, you may experience additional side effects from the chemotherapy drugs.

Information Standard

Information last reviewed: November 2017

Next review due: November 2020

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