• Signs and symptoms
• Treatment
• Diagnosis
• Gynaecomastia
• Should I follow a healthy lifestyle?
• Risk Factors
• • Established Risk Factors
  • Possible Risk Factors
  • Doubtful Risk Factors

Established risk factors have a large amount of scientific evidence that has clearly shown that these factors are linked to breast cancer risk.

Getting older increases the risk of many diseases, including cancer. Most men who develop breast cancer in England are aged over 60.

In a small number of cases, breast cancer runs in the family. This is known as familial or hereditary breast cancer. A family history of breast cancer is identified as an unusually high number of close relatives with breast or other types of cancer, breast cancers at a young age, or in men as well as women.

Men with breast cancer are more likely to have a family history of breast cancer than women with breast cancer. About 20% of men with breast cancer also have a close relative that has had breast cancer. In women, around 5% of all breast cancers are due to inherited faults in breast cancer genes (called BRCA1 and BRCA2) that lead to a high risk of developing the disease. Faults in the BRCA genes are thought to be more common than this in men who have breast cancer.

If you do have a family history of breast cancer then your risk of developing breast cancer may be increased. If you have concerns about any cancers in your family then you should see your GP. They can work out if your family history suggests that you have an increased risk of breast cancer and help you to work out the best option for you. For more information about hereditary breast cancer please see the family history section.

Exposure to high levels of ionising radiation in the chest area, for example because of radiation therapy to treat cancer in the chest (e.g. Hodgkin’s lymphoma) has been shown to increase the risk of breast cancer in men. The increase in risk is thought to be less for men than for women since breast cancer in men is rare anyway, so this is thought to affect a very small number of men overall.

All men normally produce high levels of androgens (male hormones), such as testosterone, as well as low levels of the female hormone oestrogen. Oestrogen promotes the growth of many breast cancers in women and may have a similar effect in men. Therefore, any condition that changes the levels of male and female hormones in the body may increase the risk of male breast cancer. Some of these conditions are listed below:

• Klinefelter’s syndrome
• Liver disease
• Obesity
• Testicular disorders
• Oestrogen therapy