1 The Normal Breast

The adult female breast lies between the second and sixth ribs, the sternal edge and the mid-axillary line. Breast tissue is found in the axilla as the ‘axillary tail.’

The breast ‘stroma’ makes up the majority of the breast volume. In the non-lactating state, adipose tissues (fat) and fibrous connective tissue make up  the breast stroma.

The normal female breast is a mixture of connective tissue, blood vessels, nerves and fat, with a covering of skin. It contains breast lobules and ducts that, from puberty to menopause, are under hormonal control.

The physiological changes that occur with the monthly cycle and during pregnancy and lactation can give rise to a number of worrying but benign focal changes, such as cysts.

The skin of the breast is thin; it contains hair follicles, exocrine sweat glands and sebaceous glands, just like skin on other parts of the body. The nipple contains sensory nerve endings, sebaceous and apocrine sweat glands.

The areola is circular and pink/brown in color.  So the areola includes Morgagni tubercles which are the openings of the large glands near the periphery (or edge) of the areola.

More about Normal Breast Anatomy … Sorry

There are muscle elements that envelope the breast, the ‘superficial pectoral fascia,’ that is continuous with the superficial abdominal fascia. The breast tissue lies on the deep pectoral fascia, covering the deep muscles called the ‘pectoralis major’ and ‘serratus anterior.’ The suspensory ‘ligaments of Cooper’ connect the two fascial layers and provide a fibrous support for the breast.

The internal mammary artery provides the main blood supply to the breast but the internal mammary arteries supply the upper outer quadrant.  The lymphatic drainage of the breast is to the internal mammary (IM), axillary and clavicular lymph nodes.

• Level I lymph nodes are lateral to the pectoralis minor muscle
• So, Level II lymph nodes are behind the pectoralis minor muscle
• Level III lymph nodes are above the pectoralis minor muscle.