This information is about early breast cancer, for other types
of breast cancer, visit Cancer Australia's website, or call 13
11 20. See also our genetics and breast cancer, breast
reconstruction and prosthesis, breast cancer trials or breast
health pages. Women and men both have breast tissue. In women,
breasts are made up of milk glands. The milk gland consists of
lobules, where milk is made, and tubes called ducts that take
milk to the nipples. In men, the development of the lobules is
suppressed at puberty by testosterone, the male sex hormone.
Both female and male breasts contain supportive fibrous tissue
and fatty tissue. Some breast tissue extends into the armpit
(axilla). This is known as the axillary tail. The armpits
contain a collection of lymph nodes (also called lymph glands),
which are part of the lymphatic system. The lymphatic system is
part of the immune system and protects the body against disease
and infection. Breast cancer occurs when the cells lining the
breast ducts or lobules grow abno