While breast cancer is much more common in women compared to men, it is still possible for men to develop breast cancer. In fact, 1 percent of all breast cancers occur in males. Moreover, over 2,000 cases are diagnosed and 450 men die of breast cancer each year in the U.S. alone. It is also important to note that males develop breast cancer similar to those in females. Types of breast cancer found in men include intraductal carcinoma, invasive ductal carcinoma and male inflammatory breast cancer. Male breast cancer tends to be more common in older males compared to young males. However, males of all ages are at risk of developing breast cancer. Genetic predispositions, primarily BRCA2 mutations, have been shown to both increase the risk of developing male breast cancer and lower the age of breast cancer onset.
Differences Between Male and Female Breast Cancer
While many are unaware, both men and women have breast tissue. Until puberty, both male and female breast tissue is very similar. During puberty, the ovaries produce female hormones that allow the breast to develop and differentiate, forming ductal systems, milk-producing lobules and increased fatty or stromal tissue. In contrast, during puberty in males, the testicles produce hormones that prevent the growth and differentiation of the breast tissue.
Since men have less breast tissue compared to women, it is much easier to identify breast tumors or abnormalities in men. However, since breast cancer is much more common in women, many men consider breast cancer to be only a female cancer and rarely see physicians for breast abnormalities. Many men ignore the initial signs of breast cancer and tend to attribute them to infection or other causes.
The most common breast abnormality in men is non-cancerous and is a condition called gynecomastia, an increasein the amount of breast tissue. It is most commonly found in adolescent boys and is related to changes in the hormone balance during puberty. However, older men with hormonal imbalances can develop this condition. Gynecomastia is characterized by a button-like or disc-like growth under the nipple and areola. While the cause of gynecomastia is not fully understood, certain factors have been linked to its development such as liver disease, Klinefelter’s syndrome and certain medications (ulcer and heartburn therapies, high blood pressure drugs and heart failure medications).
The most common malignant breast abnormalities or breast cancers found in men are similar to those found in women and include: invasive ductal carcinoma and intraductal carcinoma. In much more rare cases, cancer such as male inflammatory breast cancer and Paget’s disease of the nipple has also been diagnosed. It is important to note that lobular neoplasia, a marker for increased breast cancer risk in women, has yet to be identified in men.
Both environmental and genetic factors influence the risk of being diagnosed with male inflammatory breast cancer. These risk factors include:
- Advanced age – the average age of male breast cancer diagnosis ranges between 60 to 70 years old.
- Family history – approximately 20 percent of men diagnosed with breast cancer have a close relative (male or female) that has or had breast cancer.
- Exposure to radiation – usually occurs in lymphoma patients
- Liver disease – males with severe liver disease have lower levels of androgens and higher levels of estrogen, which puts them at risk for developing breast cancer.
- Estrogen treatment – while the elevation in risk is slight, estrogen treatment has been associated with male breast cancer.
- Gender-changing procedures – hormone therapy in men transitioning to women can elevate the risk of breast cancer.
- BRCA2 mutations – male breast cancer is more strongly associated with BRCA2 mutations compared to BRCA1 mutations.
- Klinefelter’s syndrome (born with 2 or more X chromosomes) – this condition is associated with reduced androgen levels and elevated estrogen levels, which results in an increased breast cancer risk.
This cancer is characterized by the blockage of lymph vessels within the skin of the breast. In this cancer, the breast is often swollen and red or inflamed. It generally occurs in men at an older age compared to women. Common symptoms of this condition include the presence of a breast lump, breast swelling, skin dimpling or puckering, nipple retraction (the nipple turns inward), redness or scaling of the nipple, or breast skin and nipple discharge.
The prognosis for this condition is often worse than female breast cancers. While many breast cancers can be detected in their early stages, male breast cancer tends to be diagnosed in later stages than female breast cancer. Since breast cancer survival rates are highly dependent on the stage of the cancer, survival rates in male cases tend to be lower than in females. In fact, males with advanced breast cancer (Stage III-IV) have a 5-year survival rate of approximately 25 to 50 percent.
The treatment choice for this type of cancer is highly dependent on the stage of the cancer. Treatment options include:
- Surgery – removal of the breast, the lining of the chest muscles and part of the chest wall muscles. Sometimes the axillary lymph nodes may be removed to determine whether the cancer has spread.
- Radiation therapy – the use of high-energy rays to help reduce the growth and division of cancer cells. May also be used to reduce the tumor burden before surgery or chemotherapy.
- Chemotherapy – The use of anticancer drugs to stop the growth of cancer cells. May also be used following surgery in cases where the cancer has spread or to ensure that cancer cells that may be present following surgery are killed.
- Hormone therapy – The use of drugs to block the activity of the estrogen and progesterone receptors, the receptors involved the growth of breast tumors. It is important to note that over 80% of male breast cancers express the estrogen receptor.
National Cancer Institute – https://www.cancer.gov/cancertopics/factsheet/Sites-Types/IBC
The American Cancer Society – https://www.cancer.org/
The University of Pennsylvania’s Oncolink document, "NCI/PDQ Physician Statement: Male Breast Cancer," is available at https://cancer.med.upenn.edu/