November 23, 2022 Author : Sílvia Alexandre Silva Breast cancer is rare in men, but its incidence has been increasing . Less than 1% of male neoplasms and less than 1% of all breast cancers diagnosed is breast cancer. In the USA, 1 in 100 breast cancer cases in Caucasians and 7 in 100 cases in African Americans are in men. In this country, the incidence has increased about 25% in the last 25 years. There is not a single known cause for breast cancer in men, but hormonal, genetic and environmental factors are known to intervene . Due to the disease rarity, results of studies are still scarce, and the treatment is based on the therapeutic guidelines available for breast cancer in women. Several factors increase the risk of developing male breast cancer. Risk factors for breast cancer in men Age and ethnicity The incidence of breast cancer in men increases with age and more significantly after the age of 50. It has a peak incidence around 65 years of age. The incidence is also higher in African American men and in male populations in Central Africa , which may be related, in this case, to a higher incidence of endemic infectious liver diseases in these countries. In Asian populations, the incidence of breast cancer, both male and female, is lower than that of the general population. Family history Several population studies estimate that 15%-20% of men with breast cancer have at least one first degree family member with the disease. As in women, men with direct family members with breast cancer are two to three times more likely to develop the disease. The risk increases with the number of family members with the disease . However, screening for breast cancer in men with a family history is not recommended as, despite everything, the absolute risk in these populations is still considered very low. Klinefelter syndrome Klinefelter syndrome is a rare genetic disorder associated with an extra X chromosome in men. Clinically it is manifested by gynecomastia and testicular dysgenesis. Men with this syndrome are 20 to 50 times more likely than the general population to develop breast cancer. This is thought to be primarily due to the low level of androgens and high levels of circulating gonadotropins. Hormonal imbalances High estrogen levels are associated with an increased risk of breast cancer in men. As with women, men who have conditions such as obesity or alcoholism have higher levels of endogenous estrogens and thus an increased risk of breast cancer. Liver cirrhosis , whatever its cause (alcoholic, viral, among others), and testicular dysfunction (due to cryptorchidism, testicular trauma, congenital inguinal hernia) are risk factors for male breast cancer due to the related hormonal changes, with an imbalance between estrogen and androgen levels favoring the former. Gynecomastia (abnormal male breast development), often associated with chronic liver disease and various drugs, does not appear to be a precursor to male breast cancer. However, they share risk factors, so there may be some association. Hormonal treatments Exogenous estrogen treatments in transgender people and the long-term treatment with anti-androgens and estrogens that may be indicated in prostate cancer have also been reported to increase the risk of male breast cancer . Exposure in a work context Professional environments associated with exposure to high temperatures, ionizing radiation, electromagnetic radiation or some chemical compounds such as combustion products , seem to be associated with a higher risk of breast cancer in men. Heredity Everyone has two copies of the BRCA1 and BRCA2 genes, each inherited from each parent. Mutations in these genes are associated with an increased risk of several cancers. Breast cancer is one of the main ones and mutations can be transmitted to descendants. There is an increased risk of male breast cancer when mutations in the BRCA2 gene and, less often, in the BRCA1 gene are present. One in each 40 Ashkenazi Jewish women has a BRCA gene mutation. Thus, men from this population will also be more likely to carry BRCA gene mutations. Risk factors and prevention of breast cancer Although breast cancer is rare in men, this disease needs to be known . The diagnosis of breast cancer in men is usually made in advanced stages of the disease and has, therefore, a worse prognosis. Controlling modifiable risk factors is an important step in preventing male breast cancer: Avoid overweight and obesity and reduce the consumption of alcoholic beverages. Also do a breast self-exam regularly , especially from the age of 50 and find out if you have other risk factors. If you need or have questions, seek medical help. An earlier diagnosis is generally associated with a more successful treatment and a more favorable prognosis . Read also about symptoms, diagnosis and treatment of male breast cancer . Meet the general surgery clinical teamf rom Hospital da Luz network and book your consultation The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
