What’s the difference? Male breast cancer and female breast cancer

Despite outward appearances, the structure of men’s and women’s breasts are very similar. So, why do so few men get breast cancer?

Despite outward appearances, breasts in men and women are built very much the same. Human breasts in both sexes have nipples, fatty tissue, breast cells and ducts. Men and women also share some of the same risk factors for breast cancer. Both genders may have inherited mutations in their BRCA1 and BRCA2 genes that may increase cancer risk. And both genders produce the hormone estrogen, which at certain levels may increase breast cancer risk. So why do so few men get breast cancer?

“In general, the incidence of breast cancer in men is far less than in women because although the breast tissue in both are similar, male breast tissue is mainly fat and fibrous tissue called stroma and they have fewer ducts and lobules,” says Sramila Aithal, MD, Hematologist & Medical Oncologist at our Philadelphia hospital. When women’s breasts mature during puberty, they develop working lobules and milk ducts to produce and carry milk after childbirth. Most breast cancers in women develop in those ducts and lobules. Most men produce far fewer and smaller ducts and may not produce lobules. Inherited gene mutations may increase cancer risk in both sexes, but are likely to affect genders differently. While BRCA mutations significantly increase a man’s risk of breast cancer, men with those mutations are at a higher risk of prostate cancer more than breast or other cancers.

And women generally produce more estrogen than men, which may increase cancer risk. “One reason for its rarity in men may be related to their lower estrogen levels,” says Cynthia Lynch, MD, Medical Director of the Breast Center at CTCA Phoenix. Men with increased estrogen levels may develop a condition called gynecomastia, in which breast tissue in males may grow or swell. “Gynecomastia is not a risk factor for male breast cancer, but when discovered does need to be differentiated from male breast cancer,” Dr. Lynch says. “Additionally, some conditions that predispose men to gynecomastia through increased estrogen levels may also predispose them to male breast cancer.”

A unique set of challenges

About 1 percent of all breast cancers diagnosed in the United States are in men. In 2019, about 2,700 men are projected to develop breast cancer, according to the American Cancer Society, compared to 270,000 women. Breast cancer in women is the most common cancer diagnosed in the United States. Measured alone, breast cancer in men would rank behind at least 30 other cancers in the number of yearly diagnoses. Discover more breast cancer statistics.

The rarity of breast cancer in men, as with rare cancers in general, may create unique challenges for those who develop it and doctors who treat it. “Treatment of breast cancer in males is typically guided by studies that were performed in women with breast cancer,” Dr. Lynch says. “While there are few differences in treatment, there are some additional considerations when using hormone therapy in males with breast cancer.” Also, men usually are not taught to screen themselves for breast cancer and most are unaware of the symptoms of the disease. And men who might develop symptoms of breast cancer may choose to ignore them because of perceived stigmas and fear of emasculation. As a result. men usually are diagnosed with breast cancer at a later age and with the cancer at a later stage. “Overall, men may have poorer outcomes than women due to being diagnosed at a more advanced stage and at an older age,” Dr. Aithal says. The average age of a man diagnosed with breast cancer is 68. The average age of a woman at diagnosis is 62 and about one-third of breast cancer cases occur in women younger than 55, according to the National Cancer Institute>

The stigma of shame

A breast cancer diagnosis may be emotionally devastating for men and women. Patients may deal with a sense of loss, especially if surgery is required to remove a breast. They may also be faced with body image and intimacy issues. Some men may feel less masculine after a diagnosis and be less likely to seek support, Dr. Aithal says.

“Breast Cancer in males may be quite distressing,” she says. “Men often experience more embarrassment shame, loneliness and anxiety. Many do not express emotions and, they are less likely to be involved in support groups because there are fewer men with breast cancer and they are unlikely to join a women’s support group.” Support groups for men with breast cancer can be found at the Susan B. Komen Foundation website, hisbreastcancer.org and The Male Breast Cancer Coalition. “Given this is primarily a malignancy in women, studies have identified that men can feel isolated in their diagnosis.” Dr. Lynch says. “They also report feelings of embarrassment and emasculation. Raising awareness of male breast cancer is one way to help alleviate feelings of embarrassment and isolation surrounding this diagnosis.”

More about male breast cancer

Learn more about rare breast cancer types.