Breast

Question 1

Breast overview

Answer 1

Spans over the 2nd-6th ribs

Lies superficially to the pectoralis major, serratus anterior and external oblique muscle

Question 2

Axillary process/tail

Answer 2

extended portion of glandular and adipose tissue that projects into the axilla

Question 3

Areola

Answer 3

Raised sebaceous glands within the areola that secrete lubricating fluid that protect the areola and nipple
Widens during pregnancy

Question 4

Mammary glands

Answer 4

Lobes (15-20):

• Consists of 20-40 terminal lobules (functional unit of breast) that are formed by cluster of alveoli and secrete milk
• Each lobule is drained by one lactiferous duct
• Separated by fibrous septae (Ligament of Cooper)

Lactiferous ducts (15-20):
- Converge near the nipple to form the lactiferous sinuses (store milk) before opening at the apex of nipple

Question 5

Fibrous septae (Ligament of Cooper)

Answer 5

• Attach and secure breast to the underlying pectoral fascia and dermis
• Separate the secretory lobes of breast

Question 6

Arterial supply

Answer 6

Medial Portion:
1) Perforating branch of internal thoracic artery

Lateral Portion:

1) Mammary branch of lateral thoracic artery (branch of axillary artery)
2) Mammary branch of intercostal arteries

Question 7

Venous supply

Answer 7

Drains into the axillary and internal thoracic veins

Question 8

Innervation

Answer 8

Anterior and lateral cutaneous branches of 4th-6th intercostal nerves

Question 9

Lymphatic supply

Answer 9

Lymph of breast drains into:

1) Axillary lymph nodes (75%)
2) Parasternal lymph node (20%)

Groups of Axillary lymph nodes:

1) Apical
2) Central
3) Lateral (Brachial)
4) Posterior (Subscapular)
5) Anterior (Pectoral)

Important for metastasis of cancer:

• Sentinel lymph node biopsy
• Mastectomy