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What is breast cancer?

Breast cancer is caused by the abnormal growth of cells that make up breast tissue. Men have a small amount of breast tissue so it’s possible for them to get breast cancer, but it’s a much rarer condition in men than women.

It’s important to remember that most breast lumps occurring in men are not cancer.

Breast cancer in men has some similarities to breast cancer in women but there are some biological differences that can affect the choice of treatments1.

Breast cancer occurs in around 12 Australian men per million each year2, and accounts for about one out of every 170 new cases of cancer3.

The incidence of breast cancer in Australian males is slowly increasing, with about 165 new cases expected in 20214.

Symptoms of breast cancer

Breast cancer in men is usually noticed as a painless lump behind the nipple and areola (the ring of pigmented skin surrounding a nipple), because that’s where the breast tissue is found4.

Other signs of male breast cancer can include:

  • Nipple retraction
  • An open sore (ulcer)
  • Bleeding from the nipple (this is rare5).

In most cases, breast cancer occurs in only one breast6.

Causes of breast cancer

The chance of getting breast cancer is affected by genetics7 and age4.

Men’s risk of breast cancer is increased by:

  • A family history of breast cancer
  •  Radiation exposure
  • Increasing age
  • Conditions that affect the balance between androgens and oestrogens (including Klinefelter syndrome, obesity, and oestrogen treatment for prostate cancer or gender affirmation)3,7.

Diagnosis of breast cancer

If your doctor is worried changes in your chest might be breast cancer, they’ll usually send you for an X-ray or ultrasound scan, and sometimes a biopsy8.

Treatment of breast cancer

Surgery to remove the breast tissue, nipple and areola is usually the first step of treating breast cancer in men9.

Treatment with tamoxifen (a medication that affects the action of oestrogens) for at least five years after surgery is commonly recommended. Chemotherapy or radiation therapy is used in some cases if there is a significant possibility cancer has spread8,9.

Health effects of breast cancer

Long-term monitoring is necessary for all people who have had breast cancer because of the risk of recurrence9.

Breast cancer is often diagnosed at a more advanced stage in men than women. Because of this, outcomes can be worse for men than women. However, when matched for a patient’s age and disease severity, the risk of dying from breast cancer is not different between genders7.

What to do about breast cancer

If you notice changes in your chest, particularly a lump in or behind your nipple or areola, see your doctor straight away because early diagnosis of breast cancer will help you achieve the best outcome.

You shouldn’t assume any changes in your breast tissue are benign.

Questions to ask your doctor about breast cancer

  • How can we rule out breast cancer as the cause of the changes I’ve noticed?
  • What investigations should be done?
  • Should I be tested for a genetic mutation that might be responsible for my breast cancer?
  • What other medical specialists will I need to see as part of my care?

[1] Gucalp et al., 2019. Male breast cancer: a disease distinct from female breast cancer. Breast Cancer Research and Treatment

[2] Cancer incidence. Cancer Australia, Accessed 22 March 2021.

[3] Lomma et al., 2021. Male Breast Cancer in Australia. Asia-Pacific Journal of Clinical Oncology

[4] Elimimian et al., 2020. Male Breast Cancer: A Comparative Analysis from the National Cancer Database. The World Journal of Men's Health

[5] Leon-Ferre, et al., 2018. A contemporary review of male breast cancer: current evidence and unanswered questions. Cancer and Metastasis Reviews

[6] Sun et al., 2012. Synchronous Bilateral Male Breast Cancer: A Case Report. Journal of Breast Cancer

[7] Weiss et al., 2005. Epidemiology of male breast cancer. Cancer epidemiology, biomarkers & prevention

[8] Breast Cancer in Men. Cancer Australia, Accessed 22 March 2021.

[9] Khattab et al., 2021. Male Breast Cancer. In: StatPearls,