Breast Anatomy and Development

Question 1

Development of mammary glands begins in what week of embryonic life?

Answer 1

4th week

Question 2

Milklines extend from what regions?

Answer 2

Axilla to inguinal

Question 3

With each menstrual cycle the breast undergoes what changes?

Answer 3

proliferative and involutional changes

Question 4

Ages 6-8 the glandular tissue of one breast may start to develop.
Tender discoid lump beneath areola.
Resolved by age 9 or puberty.

Answer 4

Unilateral early ripening (premature thelarche)

Question 5

Causes of precocious puberty?

Answer 5

Estrogen secreting ovarian or adrenal tummor.

Changes within hypothalamus or pituitary glands.

Question 6

Presence of accessory (supernumerary) nipples?

Answer 6

Polythelia

Question 7

What is the most common breast anomaly that can affect male or female? Can develop anywhere along the milkiness.

Answer 7

Polythelia

Question 8

Accessory breast, more common without nipple/areola and often forms in the axillary region is called what?

Answer 8

Polymastia

Question 9

Term for absence of nipple?

Answer 9

Athelia

Question 10

Term for absence of breast and nipple?

Answer 10

Amastia

Question 11

Absence of breast tissue secondary to excessive radiation exposure or from surgical excision?

Answer 11

Amazia

Question 12

Breasts are modified ____?

Answer 12

apocrine sweat glands

Question 13

Breasts overlie which ribs?

Answer 13

2nd to 6th

Question 14

The nipple is a what?

Answer 14

Fibromuscular papilla

Question 15

Small ___ ducts exit the surface of the nipple and drain the ____ ducts.

Answer 15

excretory, lactiferous

Question 16

What is the areola?

Answer 16

pigmented skin that encircles the nipple.

Question 17

The areola contains numerous sebaceous glands (Montgomery’s glands) that do what?

Answer 17

Release fatty substance that protects the nipple during lactation.

Question 18

Functional glandular tissue is composed of how many lobes?

Answer 18

15 to 20

Question 19

What is the TDLU structure?

Answer 19

Acini > small branching ducts (lobule) > main lactiferous duct (segment duct) > lactiferous sinus (ampulla) > nipple

Question 20

What is the functional unit of the breast?

Answer 20

Terminal duct lobular unit (TDLU)

Question 21

Supportive elements of the breast and consist of fat and fibrous connective tissues are what?

Answer 21

stromal tissue

Question 22

This extensive capillary network allows the exchange of hormones into and secretions out of the lobule.

Answer 22

Loose intralobular stroma

Question 23

Breast is also supported by dense connective tissue sexton called what?

Answer 23

Coopers ligaments

Question 24

What is the main arterial supply of the breast?

Answer 24

Branches from lateral thoracic artery (external mammary artery) and branches of internal mammary (thoracic) artery.

Question 25

What veins can provide a pathway for bone metastasis?

Answer 25

Intercostal veins that anastomose with vertebral veins.

Question 26

Branches of what nerve primarily innervates the breast?

Answer 26

intercostal (thoracic) nerves

Question 27

Branches of the supraclavicular nerve innervate what aspect of the breast?

Answer 27

Superior and lateral

Question 28

Originate in the interlobular connective tissue and the walls of the lactiferous ducts?

Answer 28

lymphatic channels

Question 29

What part of the lymphatic channels drain the breast?

Answer 29

superficial channels

Question 30

What percent of lymph drains into the axillary chain?

Answer 30

>75%

Question 31

How many nodes are in the axillary chain?

Answer 31

30 to 40

Question 32

The axillary nodes are further subdivided into anatomic groups and correspond to the nearest major vessel. these groups are:

Answer 32

``` External mammary subscapular axillary (lateral to ax artery) central (medial to ax artery) subclavicular intrasectoral (Rotters) ```

Question 33

Nodes lateral to pectoralis minor muscle are what location for surgical classification?

Answer 33

level I, low axilla

Question 34

Nodes deep to pectorals minor muscle or between med and lat boarders, including Rotters nodes, are what location for surgical classification?

Answer 34

Level II, mid axilla

Question 35

Nodes medial to pectoralis minor and subclavicular nodes are what location for surgical classification?

Answer 35

Level III, high axilla

Question 36

Breast tissue responds to hormones produces by?

Answer 36

Ovaries, hypothalamus and pituitary gland, placenta, thyroid, and pancreas

Question 37

Hormone responsible for ductal proliferation?

Answer 37

Estrogen

Question 38

Hormone responsible for lobular proliferation and growth?

Answer 38

Progestrone

Question 39

Hormone present during late pregnancy and lactation?

Answer 39

Prolactin

Question 40

What organ produces estrogen to stimulate growth and division of ducts?

Answer 40

Ovary

Question 41

What organ produces progesterone to stimulate an increase in size and number of lobules and maturation of acini?

Answer 41

Ovary and placenta

Question 42

What hormone and gland prevents release of prolactin until milk production is needed?

Answer 42

Hypothalamus | Prolactin Inhibiting factor

Question 43

What gland releases prolactin to stimulate acini to produce milk?

Answer 43

Anterior pituitary

Question 44

What hormone and gland initiates contraction of ducts for flow of milk during lactation?

Answer 44

Oxytocin | Posterior pituitary

Question 45

Placental lactogen and HCG are produced by what?

Answer 45

placenta