🩺 Breast and Axilla Study Guide
1. Review of Anatomy and Physiology
Surface Anatomy
• Breasts extend from the 2nd to 6th ribs, sternum to mid-axillary line.
• Tail of Spence: superolateral extension into the axilla.
• Nipple: rough, round, central protuberance.
• Areola: 1–2 cm radius, contains sebaceous glands.
Internal Anatomy
• 15–20 lobes radiating from the nipple.
o Each lobe → lobules → alveoli (milk production).
o Alveoli drain into lactiferous ducts → sinuses → nipple pores.
• Cooper’s ligaments support breast tissue; contraction → skin dimpling.
Lymphatic Drainage
• 75% drains into ipsilateral axillary nodes:
o Pectoral (anterior) – lateral edge of pectoralis.
o Subscapular (posterior) – lateral scapular edge.
o Central – deep in axilla.
o Lateral – along upper humerus.
o Others: internal mammary, supraclavicular, infraclavicular nodes.
Development
• Tanner Stages (1–5): from prepubertal nipple elevation → mature adult breast.
• Embryology begins at 5 weeks gestation.
2. Framework for Breast and Axilla Assessment
Health History Interview
Ask about:
• Breast pain (cyclic/noncyclic), lumps, nipple discharge (color, timing, relation to touch), swelling,
trauma, rash, or changes in contour/skin.
• Personal/family history of breast disease or cancer (BRCA1/2, chest radiation).
• Menstrual/reproductive history (menarche, menopause, parity, breastfeeding).
