BREAST ANATOMY

Breasts are made up of lobules (milk-producing glands) and ducts (tubes that carry milk to the nipple), which are surrounded by fatty and fibrous tissue. 

Breasts contain a network of thin tubes called lymph vessels. These are connected to groups of small bean shaped structures called lymph nodes. The lymph nodes closest to the breast are in the armpit (axillary nodes). There are also lymph nodes under the breastbone (internal mammary nodes) and in the neck (supraclavicular nodes).