Nerve Supply
By the anterior and lateral cutaneous branches of the 4th, 5th & 6th Intercostal nervs.
Lymphatic drainage of the Breast
Breast is drained by two sets of Lymph Vessle:
a) Lymphatics of the Parenchyma of the breast.
b) Lymphatics of the skin over the breast.
a) Lymphatics of the Parenchyma: The lymph vessels originating form a plexiform network in the intterlobular spaces and in the walls of the lactiferous ducts drain the whole parenchyma. They converge towards the areola and forms the Sub areolar plexus of Sappey, which is a collection of large lymph vessels situated beneath the areola. This plexus also receives the lymph from the skin of the areola and nipple.
The lymph from the sub areolar plexus is drained by two main lymph trunks: One from ist inner and the other from its outer part; these two are uniting to form a single trunk which ends in the pectoral group of axillary lymph nodes. Before union these two trunks receive. each a small lymph vessel draining the parenchyma directly (without passing through the Sappey’s plexus)
From the uper & outer quadrant of the parenchyma one of the lymph vessels passes upwards and pierces the deep fascia. Pectoral is major, clavi-pectoral fascia and ends in the apical group of the axillary lymph nodes.
Some lymph vessels from the lower & inner quadrant of the parenchyma pass downwards to communicate with the sub-peritoneal lymph plexus, passing through the linea alba.
b) Lymphatics of the Skin : The lymph-vessels of this group drain the whole skin over the breast except that of the areola and nipple which drain into the Supply’s plexus.
For convenience, the distribution of lymphatics from the different parts of the skin may be arranged by dividing the breast into four Quadrants (upper & outer , Upper & inner; lower & outer and lower & inner) by two imaginary planes, one vertical and the other horizontal, passing through the nipple.
1) The upper & outer Quadrant: Is drained by two sets of lymph vessels: 9a) to the pectoral group of axillary lymph nodes (b) to the infraclaviculary lymph nodes.
2) The Lower & outer Quadrant: Is also drained by two sets: (a) to the pectoral lymph nodes (b) to the lymph nodes of the abdominal parieties.
3) The upper & inner Quadrant: Is drained by three sets: (a) to the infraclavicular lymph nodes, (b) to the internal mammary lymph nodes, (c) to the lymphatics of the opposite side by crossing the middle line.
4) The Lower & inner Quadrant: Is also drained by three sets: (a) to the infraclacicular lymph nodes, (b) to the internal mammary lymph nodes, (c) to the lymphartics of the opposite side by crossing the middle line.
Of the “Cancer Breast” in females relating to its Lymphatic drainage may be expressed as follows :
a) Upper & Outer quadrant : Not dangerous.
b) Lower & Outer quadrant : less dangerous.
c) Upper & Inner Quadrant: Dangerous, as for the chances of spreading to the mediastinum.
d) Lower & Inner Quadrant: Very dangerous. as for the chance of spreading to the peritoneal cavity as well as to the mediastinum
