The Impact of Genetics on Male Breast Cancer
Genetics is a key factor in male breast cancer, much like in female breast cancer. Although the majority of breast cancer cases occur without a known genetic cause, a small percentage of breast cancers in both sexes can be attributed to inherited genetic mutations.
As male breast cancer is a relatively rare condition, the genetic factors contributing to its development are not as well studied as those for female breast cancer. However, some genes have been identified as being associated with male breast cancer risk.
BRCA2 and BRCA1 (breast cancer gene 2 and breast cancer gene 1)
Mutations in the BRCA2 gene are associated with an increased risk of male breast cancer, similar to its role in female breast cancer. Men carrying BRCA2 mutations are more likely to develop breast cancer than those without the mutation.
While BRCA1 mutations are more commonly associated with female breast cancer, they can also increase the risk of male breast cancer, although less frequently.
The BRCA genes play a critical role in repairing damaged DNA and maintaining the stability of the cell's genetic material. When BRCA1 or BRCA2 genes are mutated, their ability to repair DNA is impaired, leading to an increased risk of breast and ovarian cancers in women, breast and prostate cancers in men, as well as other cancers in both genders.
Inherited BRCA mutations substantially elevate the risk of male breast cancer. The lifetime risk of male breast cancer has been estimated at 1- 5% for BRCA1 and 5-10% for BRCA2 carriers, vs 0.1% in the general male population.
PALB2 (partner and localizer of BRCA2)
PALB2 is a gene involved in repairing damaged DNA and interacts with BRCA2. Mutations in the PALB2 gene have been found to increase the risk of male breast cancer and are also associated with an elevated risk of female breast cancer.
CHEK2 (checkpoint kinase 2)
The CHEK2 gene is involved in DNA repair processes. Certain mutations in CHEK2 have been linked to an increased risk of male breast cancer, particularly in families with a history of breast cancer.
PTEN (phosphatase and tensin homolog)
PTEN is a tumor suppressor gene that plays a critical role in regulating cell growth, division, and apoptosis (controlled cell death). Mutations in PTEN have been associated with an increased risk of male breast cancer.
Will this affect me?
It is important to note that while genetic mutations can heighten the risk of male breast cancer, most cases are not linked to an inherited genetic predisposition. Many cases still occur sporadically and may be influenced by a combination of environmental factors, lifestyle choices, and other unidentified genetic factors.
For individuals with a strong family history of breast or ovarian cancer, especially if male breast cancer cases are present, genetic testing for BRCA and other breast cancer-related gene mutations can be crucial. Before undergoing genetic testing, genetic counseling is recommended to discuss the potential benefits, limitations, and implications of the test results.
Learn more: Assessing Breast Cancer Risk Through Genetic Counselling and Testing
Identifying a genetic mutation in a male with breast cancer holds significance not only for the patient but also for family members. It helps identify individuals at higher risk and informs decisions about preventive measures or early detection strategies for those at risk. As research progresses, a deeper understanding of the genetic factors contributing to male breast cancer will lead to better risk assessment, early diagnosis, and improved outcomes.
Routine image-based breast screening is recommended for women. Women are encouraged to undergo age-appropriate cancer screening tests. However, there is not enough data to support such routine breast screening tests in men. This is a call for all individuals, particularly men, to prompt open discussions about cancer risk with primary care providers. Individuals at elevated risk for breast cancer should consider engaging in studies, contributing to advancements in research that can enhance our understanding of this disease and ultimately save more lives.