Breast Lecture 1 - Normal Anatomy

Question 1

what is the extent of the breast tissue, vertically and horizontally?

Answer 1

vertical: 2nd or 3rd - 6th rib
transverse: sternal edge to midmaxillary line

Question 2

what are the anatomical relations of the breast?

Answer 2

• 2/3rds of breast rests on the pectoral fascia covering pectoralis major
• 1/3rd of the breast rests on the fascia covering serratus anterior
• firmly attached to the dermis by suspensory ligament of cooper - helps support the lobules of the gland.

Question 3

each breast contains approx how many lobules of glandular tissue (parenchyma)?

Answer 3

15-20

Question 4

each lobule of the breast is drained by a?

Answer 4

lactiferous duct - opens independently on the nipple

Question 5

Breast Quadrants

Answer 5

For anatomical location and description of pathology (cysts and tumours) the breast is divided into 4 quadrants.

The axillary tail is an extension of breast tissue in the supero-lateral quadrant

Question 6

describe the male breast

Answer 6

• Rudimentary throughout life
• Formed by small ducts without lobules or alveoli
• Little supporting fibroadipose tissue
• Temporary enlargement in newborn & during puberty

Question 7

what is gynecomastia?

Answer 7

• postnatal development of rudimentary lactiferous ducts in males
• during midpuberty about 2/3rds of boys develop varying degrees of hyperplasia of the breasts

Question 8

what is polymastia?

Answer 8

an extra breast

Question 9

what is polythelia?

Answer 9

an extra nipple

Question 10

what is athelia or amastia?

Answer 10

absence of nipple or breast

Question 11

what is the blood supply of the breasts?

Answer 11

Supplied by branches of axillary artery, internal thoracid and some intercostal arteries:
- thoraco acromial artery
- lateral thoracic artery
- internal mammary (thoracic) artery

Question 12

which nerves innervate the breast?

Answer 12

• anterior and lateral cutaneous branches of 4-6th intercostal nerves
• they convery sensory fibres to the skin of the breast
• they also carry sympathetic fibres to the blood vessels and to the smooth muscle around the nipple

Question 13

breast lymphatic drainage

Answer 13

• most lymph (more than 75%) from lateral quadrants drain into axillary lymph nodes
• some lymph may drain directly to supraclavicular or inferior cervical nodes
• lymph from medial quadrants - parasternal or to opposite breast

Question 14

what is the first draining node of the breast called?

Answer 14

sentinel node

Question 15

prepuberty related breast changes

Answer 15

Neonatal breast contain lactiferous ducts but no alveoli

Until puberty, little branching of the ducts occurs

Slight breast enlargement reflects the growth of fibrous stroma and fat

Question 16

puberty-related breast changes

Answer 16

Branching of lactiferous ducts

Solid, spheroidal masses of granular polyhedral cells (alveoli)

Accumulation of lipids in the adipocytes

Question 17

post-menopausal breast changes

Answer 17

Progressive atrophy of lobules and ducts

Fatty replacement of glandular tissue

Question 18

what histological changes happen to the breast during pregnancy?
label the image

Answer 18

• Enlarged lobules (Lo)
• Acini (A) are dilated
• Epithelial cells (E) vary from cuboidal to low columnar
• (S) - septa

Question 19

label the histological slides of a normal breast

Answer 19

• Extensive branching duct system
• Surrounded by dense fibrous interlobular tissue (F) & adipose tissue (A)
• Ducts & acini are lined by two layers of cells – Luminal epithelial cells (E) & myoepithelial cells (M)

Question 20

what is colostrum?

Answer 20

a protein-rich fluid, available a few days after birth - rich in maternal antibodies

Question 21

what histological changes occur to the lactating breast?

Answer 21

• Acini distended with milk
• Thin septa (S) between the lobules
• At higher magnification (b) – Acini with eosinophilic material containing clear vacuoles
• Milk production – Suckling -Neurohormonal reflex –Prolactin & Oxytocin

Question 22

breast cancer diagnostic methods

Answer 22

• imaging - mammography and US
• FNA cytology
• core biopsy

Question 23

what is the commonest cause of death in women in 35-55 age group?

Answer 23

breast cancer
- 20% of all cancers in women

Question 24

what are some signs of breast carcinoma?

Answer 24

Question 25

list some benign breast tumours

Answer 25

• fibroadenomas
• duct papillomas
• adenomas
• connective tissue tumours

Question 26

describe Paget’s disease of the nipple

Answer 26

• erosion of the nipple resembling eczema
• associated with ductal or invasive carcinoma