It’s not just for the girls: What providers should know about hereditary MALE breast cancer

Often when people think about breast cancer, the focus is solely on females. In families with inherited risk for breast cancer, males can carry and be affected by the same gene variants as females. When males carry disease-causing (pathogenic) variants in genes such as BRCA1, BRCA2, PALB2, and CHEK2, they have an increased risk for male breast cancer.

The average risk for a male to develop breast cancer is less than 1% compared to the average risk for female breast cancer of about 12%. When a male is diagnosed with breast cancer, approximately 2% -10% are due to a hereditary predisposition that could have impacts on their family, future cancer risks, and possibly treatment. When there is an inherited risk for breast cancer in a family, there is often little education about the risks to male relatives, primarily because the female risks are significantly higher. However, multiple genes associated with female breast cancer risk also increase the risk for male breast cancer and other cancer types. Males carry pathogenic variants in breast cancer genes at the same rate as females and have the same 50% chance of passing the gene on to each of their children, regardless of sex.

The table below describes the various cancer risks associated with BRCA1, BRCA2, PALB2, and CHEK2 variants when identified in males.^1,2 These genes have the strongest correlation to hereditary risk for male breast cancer. It is important to note that this is not an exhaustive list of hereditary breast cancer genes. There are other genes that may only have an established risk for female breast cancer and are not included in the table.

Males at a higher risk for breast cancer are encouraged to have clinical breast exams every year starting at age 35. Mammograms or other imaging studies may be recommended on an individual basis.

Males may be at higher risk for breast cancer if they are obese and/or have gynecomastia (extra breast tissue) or take certain hormone medications like finasteride. Having a family history of male breast cancer and aging also contribute to risk. Additionally, males with a genetic condition called Klinefelter syndrome, in which males carry an extra X chromosome, are at an increased risk. 

Red flags for hereditary breast cancer¹ include

• Multiple close blood relatives* on the same side of the family with breast cancer and/or prostate cancer
• Females diagnosed with breast cancer aged 50 or younger, or with multiple breast cancer primary diagnoses, or triple negative breast cancer at any age
• Males, or close blood relatives of a male, with breast cancer
• Females, or close blood relatives of a female, with ovarian cancer
• Pancreatic cancer, or a first degree relative of an individual with pancreatic cancer

*Close blood relatives are defined as first- or second-degree relatives (parents, children, siblings, aunts, uncles, grandparents, nieces, nephews) related to the individual by blood (not through marriage).

Providers should discuss personal and family history with their patients to determine if genetic testing may be appropriate. For those with a personal or family history of male breast cancer, genetic testing is recommended to include at minimum all the genes associated with hereditary male breast cancer (see table above).

Hereditary breast cancer is not just a women’s health issue-male individuals with a significant family history or genetic risk can be affected, and it is important that these individuals are not overlooked in the risk assessment process based on sex alone. Providers play a key role in identifying these patients and providing awareness and education. Early screening and intervention can make significant differences in outcomes, so identifying patients eligible for genetic testing is critical.

1. National Comprehensive Cancer Network®. NCCN Clinical Practice Guidelines in Oncology. Genetic/Familial High-Risk Assessment: Breast, Ovarian, Pancreatic and Prostate (Version 1.2026). https://www.nccn.org/professionals/physician_gls/pdf/genetics_bopp.pdf
2. Campos FA, Rouleau E, Torrezan GT, et al. Genetic landscape of male breast cancer. Cancers. 2021;13(14):3535. doi:10.3390/cancers13143535 https://doi.org/10.3390/cancers13143535