Biological therapy for breast cancer

Biological therapy is treatment with substances that are made naturally in the body or that block the growth of cancer cells. Several types of biological therapy are now used to treat breast cancer. They include herceptin and lapatinib. Other types of biological therapy are being used in clinical trials, such as everolimus and sunitinib.

Herceptin (trastuzumab) is the most commonly used biological cancer treatment for breast cancer. It is a type of monoclonal antibody which attaches to a particular type of protein on some breast cancer cells. 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 it can no longer tell the cancer cells to grow. Herceptin also increases the effect of chemotherapy drugs on breast cancer cells.

Somewhere between 20 and 25 out of every 100 patients with breast cancer (20 to 25%) 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. When you are diagnosed with breast cancer, doctors test the cancer cells for the HER2 protein. The test grades your HER2 status between 0 and 3+. To benefit from Herceptin, your cells must score 3+, which means they have a lot of HER2 protein. A test result showing 0 or1+ means you are HER2 negative. But if you score 2+ it means that the result is not clear either way, so you'll probably have a more accurate test of your breast cancer cells called fluorescence in situ hybridisation (FISH testing).  FISH testing measures the amount of HER2/neu gene in the cells. The result is either FISH positive, or FISH negative. Between 20 and 25 out of every 100 women with early breast cancer (20 to 25%) have 3+ HER2 test results. 

The National Institute for Health and Clinical Excellence (NICE) has recommended Herceptin as a treatment option for women with HER2 positive early breast cancer after surgery and chemotherapy (and radiotherapy if needed). You have Herceptin through a drip every 3 weeks for a year. The guidance says you should not have Herceptin if you have any of the following heart problems

• Congestive cardiac failure
• Angina that you take medicines for
• Uncontrolled high blood pressure
• Evidence of a heart attack on a heart trace (ECG)
• Heart valve disease that is causing physical effects
• Certain abnormal heart rhythms, that are uncontrolled

If Herceptin is suitable for you, you have tests on your heart before you start treatment and every 3 months throughout your course of treatment. If there is any sign that Herceptin is causing heart problems, your doctor may recommend that you stop the treatment. You may also stop treatment if your breast cancer comes back at any point during the year of treatment.

Several trials have shown that Herceptin alongside chemotherapy for women with HER2 positive early breast cancer works better than chemotherapy alone. There is information about trials for Herceptin in early breast cancer in the breast cancer question and answer section of CancerHelp UK.

You can find details of the NICE guidelines for Herceptin in advanced breast cancer in the secondary breast cancer section of CancerHelp UK.

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

Lapatinib stops breast cancer cells growing by blocking particular growth factor receptors on their surface. The receptors are erbB1 (epidermal growth factor receptor 1) and erbB2 (HER2/neu receptor). Lapatinib can be used with a chemotherapy drug called capecitabine (Xeloda) for secondary or locally advanced HER2 positive breast cancer if other treatments, including Herceptin, are not working. Lapatinib and capecitabine are both taken as tablets so you can usually have this treatment at home after the first dose.

Lapatinib is sometimes used in combination with hormone therapy drugs called aromatase inhibitors in women who have hormone receptor and HER2 positive breast cancer. We will not know if this treatment will be available on the NHS in England and Wales until the National Institute for Health and Clinical Excellence (NICE) has assessed it. In Scotland, the Scottish Medicines Consortium (SMC) has decided that this treatment should not be available on the NHS as they say it is not cost effective.

Some trials have looked at giving Herceptin with lapatinib for advanced breast cancer. At the moment Herceptin is not licensed to be given in combination with lapatinib. 

 Research is going on into lapatinib for early breast cancer. Doctors also think that lapatinib may work for inflammatory breast cancer. To find out about trials, look at our clinical trials database. Pick 'breast' from the dropdown list of cancer types and type biological therapy into the free text search box.

Other biological therapies being researched in breast cancer trials include Sunitinib and everolimus. 

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 kinase is a type of chemical messenger (an enzyme) that plays a part in the growth of cancer cells. Sunitinib blocks the protein kinase to stop the cancer growing. Trials are looking at sunitinib for advanced breast cancer. The trials are looking at sunitinib in combination with chemotherapy drugs. 

Everolimus is pronounced ever-oh-lih-mus. It is also known by its brand name Afinitor. It is a type of cancer growth blocker called an mtor inhibitor. It stops kidney cancer cells from dividing and growing. It is being tried for other types of cancer. Trials in the UK are looking at using everolimus with chemotherapy, hormone therapy or other types of biological therapy, for HER2 positive breast cancer that has spread outside the breast. We have information about everolimus and its side effects in the cancer drugs section of CancerHelp UK.

You can find details of these trials on the CancerHelp UK clinical trials database.

Herceptin has been licensed for use in people with early breast cancer. But the research has only been carried out in women. So NICE don't have the evidence necessary to recommend the use of Herceptin in men with early breast cancer. You may still be able to have it but unfortunately it is not clear how well it will work. There is detailed information about breast cancer in men in this section of CancerHelp UK. Because breast cancer in men is very rare it is also difficult to know how well other types of biological therapy will work.

The side effects vary depending on which biological therapy drug you have. But the possible side effects of biological therapies for breast cancer include

• Tiredness (fatigue)
• Diarrhoea
• Skin changes (rashes or discolouration) – rashes may be severe for some people
• A sore mouth
• Weakness
• Loss of appetite
• Low blood counts
• Swelling of parts of the body, due to build up of fluid

Tell your doctor if you have any of these effects as you can have medicines to help to control them. There is information about the side effects of individual biological therapies in our cancer drugs section.

Look at the main biological therapy section in CancerHelp UK for detailed information. You can ask your doctor or specialist nurse to write down the names of your drugs so that you can look them up in the our drug side effects section. There are pages for all the most commonly used biological therapy drugs. Each page has information about common, occasional and rare side effects for that drug.

Scientists and doctors are working together all the time to investigate new biological therapy drugs and combinations. You can find out about current trials for breast cancer by searching our clinical trials database. Choose 'breast' from the dropdown menu of cancer types.

You may also like to contact one of the breast cancer organisations. They often have books and leaflets, some of which are free. We also have details of breast cancer books and leaflets.

You can also contact our cancer information nurses. They would be happy to help.