Targeted (biological) therapies

Targeted therapy for breast cancer in men

Targeted therapies (sometimes called biological therapies) are drugs that work differently from chemotherapy. The main targeted therapy used in breast cancer is trastuzumab (usually called Herceptin®). It is only given to men with HER2-positive breast cancer.

Trastuzumab attaches to HER2 receptors on the surface of breast cancer cells and stops them dividing and growing. It also helps the body’s own immune cells to destroy the cancer cells.

You usually have it to reduce the risk of breast cancer coming back. But it can also be given to help control secondary breast cancer.

So far research into trastuzumab has only been done in women with breast cancer. This means the benefits of trastuzumab in men are not fully clear.

How trastuzumab is given

You usually have trastuzumab every three weeks for a year. It’s given in the chemotherapy day unit or outpatient department.

You have it with chemotherapy or on its own. The nurse gives you trastuzumab as a drip (infusion), into a vein (intravenously) or as an injection under the skin (subcutaneously).

When it’s given as a drip, you have it slowly the first time (over about an hour and a half) so the nurses can check you for signs of a reaction. After this you can have it over about 30 minutes.

It only takes a few minutes to have it as an injection under the skin. But you still have to wait for an hour and a half so the nurses can check you for any reaction.

If you have trastuzumab to treat secondary breast cancer, you have it as long as it is controlling the cancer.

Side effects of trastuzumab

The side effects of trastuzumab are usually mild. You may get some side effects during the infusion or injection or up to four hours after, particularly with the first dose. These include flu-like symptoms, such as a headache, high temperature (fever) and chills, or feeling sick. They generally get better within a few hours of the drip finishing.

Another possible side effect is an allergic reaction, but this is rare. The nurses will check for signs of a reaction. If it happens, they can treat it quickly with drugs. You may get other side effects after treatment. These include diarrhoea, headaches and feeling sick.

Effects on the heart

Trastuzumab may lead to changes in the way your heart works. Usually, any effect is mild and reversible. You’ll have tests to check your heart before and during treatment to make sure the drug isn’t causing any damage. You may be given heart medicines to prevent heart problems or to treat any that develop.