Is there a role for immunotherapy in breast cancer? | ISSUE OF CONCERN

In the past few years, the rapidly advancing field of cancer immunology has produced several new methods of treating cancer, called immunotherapies or immune therapy.

Immune therapy is a treatment designed to boost the body’s natural defences to fight cancer. This can be done by stimulating the immune system to work harder or smarter to attack cancer cells or by adding components, for example synthetic immune system proteins, to a person’s immune system.

Scientists first thought of manipulating the body’s immune system to attack cancer more than 100 years ago. Making the immune system do that, however, was filled with challenges and setbacks. Before safe and effective immunotherapy could be delivered to patients, the medical community had to build a better understanding of both cancer biology and the immune system. As research on cancer immunotherapy grew, clinical trials of promising approaches followed one after another.

Many of the advances to date have been in the area of melanoma. For example, you may have heard of the drug Keytruda, an immunotherapy that is extending the lives of some people with advanced melanoma. Immunotherapy is also now being used to treat some other forms of cancer, including prostate, kidney and lung cancer.

Additional research is underway in the field of immunotherapy to:

  • understand why immunotherapy is effective in some people but not in others who have the same cancer
  • expand the use of immunotherapy to more types of cancer, including breast cancer
  • increase the effectiveness of immunotherapy by combining it with other types of cancer treatment, such as targeted therapy, chemotherapy and radiotherapy.

One of the advantages of immunotherapy over conventional systemic (whole body) treatments, such as chemotherapy, is that it has fewer side effects. This means it may be able to be given for longer periods of time or in combination with other types of treatment without adding toxic side effects. People may also be less likely to develop resistance to immunotherapy.

Historically breast cancer was thought to be less likely to respond to immunotherapy.

However, breast cancer is now one of the major cancer types for which immune-based cancer treatments are currently in development. Clinical trials underway around the world, including in Australia, are investigating the effectiveness of immuotherapy in different types of metastatic breast cancer, including triple negative and HER2-postitive metastatic breast cancer.

However, it will be several years before results of these trials will provide answers to the question of whether there is a role for immunotherapy in breast cancer and whether these treatments are superior to current treatments.

BCNA will continue to provide more information about the role of immunotherapy in breast cancer as results of clinical trials become available. Talk with your medical oncologist if you would like to learn about any clinical trials that may be relevant to you or you can visit australiancancertrials.gov.au.

 

Issue 78
Autumn 2017