Though many people think of breast cancer as something that affects only women, that’s not the case. If you follow celebrity news, you may have heard about several men who have been afflicted, including Kiss drummer Peter Criss, talk show host Montel Williams, Shaft actor Richard Roundtree, and Mathew Knowles, the father of the singer and actress Beyoncé.
Anatomically, male and female breasts are very similar—in terms of structure and positioning, as well as having the same fat and connective tissue, arrangement of blood and lymph vessels, and presence of nipples and areolas. One notable difference, however, is that women start producing large amounts of estrogen at puberty, resulting in the enlargement of breast tissue and the development of the milk-producing structures. This does not occur in men, who produce little estrogen.
Still, breast cancer in men is rare; the lifetime risk is about 1 in 800 men compared to 1 in 8 women, according to the American Cancer Society (ACS). In 2021, there were 2,650 new breast cancer cases among men compared with 281,550 in women, the ACS reported.
The thing about breast cancer in men is that it is deadlier. A large, nationwide study in JAMA Oncology in 2019 found that the five-year survival rate was 78 percent in men, compared to 86 percent in women. In part, this is due to men being diagnosed later than women and their receiving inadequate treatment, according to the researchers. But even when these factors—along with age at diagnosis and breast cancer type and stage—were factored in, men still had a nearly 20 percent higher risk of dying within five years than women. Another study, in the journal Cancer in 2020, found that the survival rate was worse for men with breast cancer who were African American, were older when they were diagnosed, or had a total mastectomy (a sign of more extensive disease).
Whether screening high-risk men is beneficial has not been well studied (see box for risk factors in men). But interestingly, a study in Radiology in 2019 found that mammograms detected 18 cases of breast cancer for every 1,000 men at high risk screened, while, for comparison, another study in Radiology, in 2017, found that the test detected about 7 breast cancers per 1,000 women at high risk—suggesting that mammograms are better at early detection in high-risk men than in high-risk women. The presumption is that women have denser breast tissue, which makes finding a cancer on a mammogram more difficult than in men.
BOTTOM LINE: Men who are at high risk for breast cancer should talk to their doctor about screening (mammogram, ultrasound, or both) and possible gene testing, whether or not symptoms are present. And, just like women, they should be aware of how the tissues in their breasts or chest wall feel and seek medical attention if they notice any irregularities or changes.
Several factors increase the risk of breast cancer in men—most of them similar to those in women. Men who have a family history of breast cancer (in a first-degree relative) or have an inherited BRCA gene mutation, particularly in BRCA2, are at higher risk for developing breast cancer (and prostate cancer if the gene defect is present). But other genes may also be involved. And men without any known gene mutations can still get breast cancer. In fact, “most breast cancers (in both males and females) are sporadic—that is, there is not a family history. In men who develop breast cancer, only one in five has a family history,” according to Rita Kwan-Feinberg, M.D., a breast surgeon and member of our editorial board.
African American men also have a higher incidence of breast cancer than white men and are more likely to die of it, though it’s not clear why. It may be a combination of differences in genetic, lifestyle, environmental, and socioeconomic factors.
Other risk factors include age, heavy alcohol consumption, obesity, and radiation exposure to the chest area (such as for treatment of lymphoma), as well as anything that increases estrogen levels in the body. That includes estrogen use (as in transgender hormone therapy and, rarely today, in the treatment of some prostate cancers), Klinefelter syndrome (a congenital condition where men have additional X chromosomes in their cells), severe chronic liver disease, and testicular abnormalities. Gynecomastia, enlargement of the male breast, may also be a risk factor, independent of body weight, as was suggested in a large NIH study in the Journal of the National Cancer Institute in 2014.
