What's New in Research for Breast Cancer in Men?

Breast cancer in men is rare and is often treated like breast cancer in women, but research is showing that there are some differences.  More research is needed.

Research into the causes, prevention, and treatment of breast cancer is under way in many medical centers throughout the world. However, most breast cancer clinical trials and research are done in women. See What's New In Breast Cancer Research? (in women) for more information on advances in breast cancer treatment.

Causes of breast cancer and breast cancer prevention

Studies continue to uncover lifestyle factors and habits that alter breast cancer risk. Ongoing studies are looking at the effect of exercise, weight gain or loss, and diet on breast cancer risk. Research is also looking to see if being overweight or obese as a teenager increases breast cancer risk in men as it does for breast cancer in women. 

Research has identified several genetic variations associated with breast cancer risk. It shows that these genetic variations affect breast cancer risk in different ways for men and women. This suggests differences in the biology of breast cancer in men and women. More research is being done on this. Scientists are also exploring how common gene variations may affect breast cancer risk. Each gene variant has only a modest effect on risk (10% to 20%), but when taken together they may possibly have a large impact.

New laboratory tests

Circulating tumor cells/tumor DNA

Researchers have found that in many breast cancers, cells may break away from the tumor and enter the blood. These circulating tumor cells (CTCs) and the DNA from these cancer cells (circulating tumor DNA [ctDNA]) can be detected with sensitive lab tests. It is thought that these “liquid biopsies” may help monitor patients while they are getting treatment. This might also be an easy way to collect tumor cells to test for new drugs or sensitivities to currently available drugs before actually giving them. Although these tests are available for general use, and the research is promising, more studies are needed.

Treatment

Radiation therapy

Men with breast cancer tend to be diagnosed with larger tumors and often have mastectomies. But it's not clear whether these men should have radiation therapy after surgery, as well. Most doctors follow the same guidelines set for women with breast cancer who have mastectomies, but it is not clear if these recommendations should be the same for men. More studies are needed to define the role of radiation after mastectomy in men with breast cancer.

Immunotherapy

Recent studies in a few types of cancer  have shown a promising new way to get immune cells called T cells (a type of white blood cell) to fight cancer by changing them in the lab so they can find and destroy cancer cells. Research for this type of treatment in breast cancer is being investigated.