Breast Cancer in women

Herceptin (trastuzumab)

Herceptin (trastuzumab) is a biological therapy (targeted therapy) that may be given to some women and men with breast cancer. It is a type of drug known as a monoclonal antibody. It works by attaching to HER2 receptors (proteins) on the surface of breast cancer cells. This stops the cancer cells from dividing and growing. It may also allow the body’s defences to fight better against the cancer cells.

Herceptin can reduce the chance of breast cancer coming back after initial treatment for early breast cancer. But it is only effective for women whose breast cancer cells have a large number of the HER2 receptors on their surface. This is known as being HER2-positive. Between 15 and 25 out of every 100 women with breast cancer (15-25%) have HER2 positive cancers (Macmillan Cancer Support Jan 2016). In women who have early breast cancer and are HER2-positive, Herceptin may be used alongside or after other treatments such as chemotherapy.

Tess, who was diagnosed with breast cancer when she was 33, was given Herceptin regularly for a year.

Side effects are usually mild, but some women may have flu-like symptoms, diarrhoea, headaches or an allergic reaction. In some women, Herceptin may cause damage to the heart muscle, which could lead to heart failure. If this happens the Herceptin will be stopped. Usually, the effect on the heart is mild and reversible. All women on this medication are advised to have a scan to check on their heart every 3 months (an echocardiogram). Because the long term effects of any heart damage is not known, Herceptin is not given to women who have serious heart problems.

Herceptin is usually given by a drip (infusion) through a fine tube (cannula) inserted into a vein. As an alternative, it may be given as an injection just under the skin surface (sub-cutaneous). It can usually be given in the outpatient department at the hospital. The first dose is given slowly, usually over about an hour and a half. After this, doses normally take about 30 minutes. After the infusion women need to stay for a short time to make sure that they don't have a reaction to the Herceptin. The drug may be given once a week or once every three weeks.

Healthtalk has a whole site on breast cancer in men, for more information see 'Herceptin for men with breast cancer.'

Last reviewed August 2018.
Last updated August 2018.

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