Immunotherapy for Breast Cancer

Immunotherapy for breast cancer taps into the body’s own immune system and primes it to kill cancerous cells. At Siteman, we offer a number of different immunotherapy options that have been shown to be effective in breast cancer patients, including vaccines and antibodies. These immunotherapies are usually offered to eligible patients through clinical trials, although some – such as monoclonal antibodies – are standard of care in certain cases.

Targeted therapy for triple-negative breast cancer

Some breast cancers do not have estrogen receptors, progesterone receptors, or large amounts of a protein called HER2/neu. Depending on the stage of its diagnosis, triple negative breast cancer can be particularly aggressive and more likely to recur than other subtypes of breast cancer. Siteman has clinical trials of immunotherapies for these patients.

Monoclonal antibody therapy

This cancer treatment uses antibodies made in the laboratory from a single type of immune system cell. These antibodies can identify substances that may help cancer cells grow. The antibodies attach to the substances and kill the cancer cells, block their growth, or keep them from spreading. They may be used alone or to carry drugs, toxins, or radioactive material directly to cancer cells, also in combination with chemotherapy.


A novel vaccine study under way at Siteman and two other centers is aimed at slowing the progress of metastatic breast cancer. Researchers at these three institutions are looking at MUC-1, a protein that is overexpressed on breast cancer cells and in many other cancers. Using a personalized vaccine, they hope to stimulate the patient’s immune system to respond strongly and produce both antibodies and T-cells, which would cause a regression of the cancer. Clinical trials may show the vaccine can also be given in early cancer.