Biological therapy for secondary breast cancer

Biological therapy is treatment with substances that are made naturally in the body or that change particular body processes. Herceptin (trastuzumab) is the main type of biological therapy used to treat secondary breast cancer. Lapatinib and sunitinib are being used in the UK in clinical trials.

Herceptin is a type of monoclonal antibody which attaches to particular proteins on some breast cancer cells.

Herceptin is also called trastuzumab. Up to 3 out of 10 breast cancers that have spread (30%) are likely to respond to treatment with Herceptin. Their cancer cells have a large amount of a protein called HER2Neu or erbB2 and are called HER2 positive. The protein is a growth factor receptor. It transmits signals from outside the cell to the inside, which make the cells grow. The Herceptin antibody attaches itself to this protein receptor and blocks it. Then the receptor can no longer tell the cancer cells to grow. Herceptin also increases the effect of chemotherapy drugs on breast cancer cells.

The National Institute for Health and Clinical Excellence (NICE) have approved Herceptin for advanced breast cancer in quite specific circumstances. They say that women with breast cancer that has spread and are HER2 positive should have treatment with

• Herceptin combined with paclitaxel (Taxol) if they haven't had chemotherapy before for advanced breast cancer, and cannot have treatment with anthracycline chemotherapy drugs (doxorubicin or epirubicin)
• Herceptin alone, if they have already had at least 2 chemotherapy treatments for advanced breast cancer. The chemotherapy should have included an anthracycline chemotherapy drug (doxorubicin or epirubicin) and a taxane chemotherapy drug (paclitaxel or docetaxel).

NICE also say that hormone treatment should have been tried first, if the breast cancer is hormone receptor positive.

You have Herceptin into a vein, through a drip or central line. The first dose takes about an hour and a half. But after that you have it over 30 to 60 minutes each time. You have Herceptin every week, or every 3 weeks, for as long as it is keeping your cancer under control. NICE recommend that Herceptin treatment should be stopped if the cancer starts to grow or spread again, unless it has only spread within the brain and spinal cord (the central nervous system).  Some research seems to suggest that it may help some people live longer even if the cancer continues to grow during treatment but we need more research to be sure. Research studies are looking at different ways of giving Herceptin. 

There is detailed information about the possible side effects of Herceptin in our section about specific cancer drugs.

Lapatinib was licensed in Europe in June 2008. It is called by the brand name Tykerb in the USA and Tyverb in Europe. Lapatinib is taken as a daily tablet. There are a number of growth factor receptors on the surface of breast cancer cells. When they are triggered, the receptors tell the cell to divide and grow.

Lapatinib blocks the activity of 2 of the receptors – erbB1 (epidermal growth factor receptor 1) and erbB2 (HER2/neu receptor). So it can help to stop the breast cancer cells growing.

Trials in the UK are looking at giving lapatinib with a chemotherapy drug called capecitabine (Xeloda) to women with secondary breast cancer or locally advanced breast cancer that is HER2 positive. Trials are also looking at using lapatinib alongside Herceptin. You can find details of the trials on our clinical trials database. Type lapatinib into the text box.

Sunitinib is pronounced sue-nit-i-nib. It is also known by its brand name Sutent (pronounced sue-tent). It is a type of biological therapy called a protein kinase inhibitor. Protein kinases are a type of chemical messenger (an enzyme) that play a part in the growth of cancer cells. Sunitinib blocks some protein kinases to stop cancer growing. Trials are looking at giving sunitinib in combination with chemotherapy for women who have already had chemotherapy for advanced breast cancer. You can find details of the trials on the clinical trials database. Choose 'breast' from the dropdown list of cancer types and type 'sunitinib' into the text box. Tick the boxes for closed trials and results if you want to see all the trials.

Herceptin research trials have only been carried out in women. So the National Institute for Health and Clinical Excellence (NICE) don't have the evidence necessary to recommend the use of Herceptin in men with breast cancer. You may still be able to have Herceptin if you have secondary breast cancer but it is not so clear how well it will work for you. There is more information about breast cancer in men in the breast cancer section of CancerHelp UK.