In men, breast cancer is very rare. There are about 370 men diagnosed each year in the UK, compared with around 48,400 cases of breast cancer in women. The symptoms, diagnosis and treatment are all very similar to women with breast cancer.

Risks and causes

As with women, the single biggest risk factor for male breast cancer is getting older. Most cases are diagnosed in men between the ages of 60 and 70.
Other risk factors are

• High oestrogen levels
• Exposure to radiation
• Family history or an inherited faulty gene
• Klinefelter's syndrome

High oestrogen levels

All men produce some oestrogen, but high oestrogen levels have been linked to breast cancer. High oestrogen levels can occur in

• Men who are very overweight (obese) – oestrogen is partly made in the fat (adipose) tissues of the body
• Chronic liver conditions, such as cirrhosis
• some genetic conditions

Exposure to radiation

Men who have been exposed to radiation repeatedly, over a long period of time, are more likely to develop male breast cancer. This is particularly true if they were young when the radiation exposure took place.

Men who have female relatives with breast cancer have an increased risk of breast cancer, especially if the women are close relatives (mother or sisters). The risk also increases if the women were diagnosed at a young age (below 40). Men, as well as women, can inherit faulty genes that can cause breast cancer.

Klinefelter's syndrome

Klinefelter's syndrome is a rare genetic condition where a man is born with an extra female chromosome. So he is XXY instead of XY. Men with Klinefelter's are about 20 times more likely to get breast cancer than the average man. This makes their breast cancer risk the same as for the average woman.

Symptoms of breast cancer in men

The most common symptom for men with breast cancer is a lump in the breast area. This is nearly always painless. Other symptoms can include:

• a discharge from the nipple that may be blood stained
• Swelling of the breast
• A sore (ulcer) in the skin of the breast
• A nipple changes
• Lumps under the arm

Diagnosis

As with women, mammograms and ultrasound scans are checked and a biopsy is taken.

Treatment

The same treatments are used for breast cancer in men as for women. These depend on the stage (size and extent) of the cancer and the type of cancer.

This content is based on information published by Cancer Help UK, the patient information website of Cancer Research UK.