Targeted therapy for breast cancer uses drugs that work in a different way to chemotherapy drugs. While chemotherapy affects all rapidly dividing cells and works by killing cancerous cells, targeted therapy targets specific particles (molecules) within cells that allow cancer to grow.
The main targeted therapy for early breast cancer is Trastuzumab (Herceptin®). This drug targets cancer cells that have a higher than normal level of the HER2 protein, which stimulates cancer cells to grow.
Learn more about:
Listen to a podcast on New Cancer Treatments – Immunotherapy and Targeted Therapy
How Herceptin works
Herceptin works by attaching itself to HER2 positive breast cancer cells, destroying the cells or reducing their ability to divide and grow. Herceptin also encourages the body’s own immune cells to help destroy the cancer cells.
Herceptin increases the effect of chemotherapy drugs on early breast cancer. Several trials have shown that Herceptin used in combination with chemotherapy for women with HER2 positive breast cancer works much better than chemotherapy alone. Some men also receive Herceptin for early breast cancer.
Some people receive Herceptin as an injection, but most are given it via an infusion into a vein. You will usually have a dose every three weeks, although some people may have weekly doses.
The first infusion may take up to 90 minutes. This is called the loading dose. The following infusions take 30–60 minutes each, and they will continue for up to 12 months. The first four doses are given while you are having chemotherapy treatment.
Side effects of Herceptin
If you are having Herceptin, your medical team will monitor you for side effects. Although side effects are uncommon with this treatment, they can include fever, diarrhoea, headache and a rash.
In some people, Herceptin can affect the way the heart works. This is more common in older people and people with pre-existing heart problems. You will have tests to check your heart function before starting Herceptin, and at regular intervals during treatment. Ask your doctor for more information about these tests.
Video: What are immunotherapy and targeted therapy?
Watch this short video to learn more about targeted and immunotherapy