Male breast cancer

While rare, men can develop breast cancer. It is the same disease that affects women, and the diagnosis, treatment and survival rates for both men and women are similar. In New Zealand, around 25 men are diagnosed with breast cancer each year.

The following factors are associated with a higher risk of male breast cancer:

• Aged over 50.
• Strong family history of breast and/or ovarian cancer (men who have several family members with breast cancer have an increased risk of developing the disease themselves.
• Inherited genetic mutations. 10-20% of male breast cancers are associated with BRCA genetic mutations.
• Prior radiation treatment to the chest. The risk is greater if radiation exposure occurred at a young age.
• High levels of oestrogen, due to obesity, heavy use of alcohol and chronic liver conditions (e.g. cirrhosis).
• Klinefelter’s Syndrome, where affected males are born with an extra X chromosome (XXY). This results in lower testosterone production and high levels of oestrogen, and affected men have the same risk for developing breast cancer as women in the general population.

Due to the lack of public knowledge of male breast cancers, men often present later for investigation and diagnosis than women. 

Symptoms of male breast cancer are similar to those experienced by women:

• A lump or area of thickened tissue, commonly situated close to, or behind, the nipple.
• Skin changes (e.g. puckering, redness or ulceration) or changes in breast shape.
• Nipple changes (e.g. retracted or distorted nipple, itchy, scaly or ulcerated skin on the nipple or areola).
• Fluid discharge from the nipple.
• Unusual breast pain or tenderness.
• Painless lump in the axilla.

Male breast cancer is diagnosed using the triple test.

Surgery

Surgery usually involves mastectomy, rather than breast conserving surgery as men do not have the required breast volume to allow for adequate cosmetic outcome. Reconstructive procedures may be used to improve the appearance of the chest wall, if required, and nipple reconstruction may be an option. A sentinel node biopsy will be performed at the time of mastectomy unless there is a high suspicion of axillary lymph node involvement or evidence of metastatic spread to the nodes. In this instance, an axillary node dissection may be offered. 

Adjuvant treatment

Adjuvant treatment, involving chemotherapy, radiation therapy or targeted therapy, is the same for men as it is for women, and depends on tumour characteristics and hormone receptor status. Most male breast cancers are hormone receptor positive. Tamoxifen is the standard course of endocrine therapy for male breast cancer, as there is not enough research to support the use of aromatase inhibitors in men. Men with HER2+ breast cancer can be treated with Herceptin as a targeted therapy. Patients will need post-treatment surveillance and should be referred for a genetics assessment.