Development, Anatomy, and Physiology of Breast

Question 1

Process by which breast develops

Answer 1

mammogenesis

Question 2

Process by which milk is produced

Answer 2

lactogenesis

Question 3

Primary function of mammary gland is ___

Answer 3

lactation

Question 4

Functions of mother’s milk

Answer 4

nourishment, passive immunity, mother/child bonding, postpartum uterine involution

Question 5

The outflow area which marks the coming together of breast glands is the ____

Answer 5

nipple

Question 6

Breast lobule

Answer 6

specialized acinar alveolar cells produce milk and pump it into the ducts

Question 7

Pigmented area around the nipple

Answer 7

areola

Question 8

Blood supply to breast

Answer 8

2/3 internal mammary, 1/3 lateral thoracic

Question 9

Lymphatic supply to breast

Answer 9

3% internal mammary, mostly axillary nodes

Question 10

2 tissue components of breast

Answer 10

epithelial (20%) and stromal (80%)

Question 11

Epithelial component of breast

Answer 11

ducts (luminal epithelia and myoepithelia) and lobules (alveolar epithelia)

Question 12

Stromal component of breast

Answer 12

fibrous connective tissue (fibroblasts) and adipose (adipocytes)

Question 13

TDLU

Answer 13

terminal ductal lobular unit –> outpouchings lined with alveolar cells

Question 14

_____ stroma is cellular compared to ____ stroma

Answer 14

intralobular vs interlobular

Question 15

Hormonal requirement for breast devleopment. Puberty:

Answer 15

estrogen –> ductal morphogenesis(elongation)

Question 16

Hormonal requirement for breast devleopment. Pregnancy:

Answer 16

progesterone and prolactin –> lobuloalveolar development

Question 17

Hormonal requirement for breast devleopment. Lactation:

Answer 17

prolactin (cortisol) and insulin in absence of estrogen/progesterone

Question 18

Which stage of breast development is hormone independent?

Answer 18

early fetal development of milk streak –> mammary bud –> primordial ductal tree

Question 19

Which stage of breast development is dependent on parental/placental sex steroids?

Answer 19

late fetal development involving canalization of ducts and parenchymal differentiation —> colostrum formation

Question 20

T/F breast undergoes cyclic changes in response to hormonal fluctuations of menstrual cycle

Answer 20

T

Question 21

Mitotic rate of glandular epithelial cells of breast is greatest during ___ stage

Answer 21

luteal –> E2 + P is more mitogenic than E2 alone

Question 22

Breast changes during luteal phase

Answer 22

volume, nodularity, sensitivity due to tissue edema and hyperemia NOT due to the epithelial changes in the breast during luteal stage

Question 23

Progesterone and estrogens inhibit lactogenic action of ____

Answer 23

prolactin

Question 24

Terminal differentiation of alveolar epithelial cells occurs during ____

Answer 24

lactation –> high prolactin levels in setting of low E2/P

Question 25

dopamine agonists like _____ inhibit lactogenesis

Answer 25

bromocriptine

Question 26

neural reflex arcs involved in milk production/ejection

Answer 26

nursing --> oxytocin --> myoepithelial contraction + suckling --> prolactin --> milk production = transcription of milk genes, induction of enzymes for lactose synthesis, induction of differentiation

Question 27

Requirements for continued lactation

Answer 27

regular removal of milk, intact hpa axis, adequate diet and nutrition

Question 28

T/F ovaries required for nursing

Answer 28

F

Question 29

Lactation induced amenorrhea

Answer 29

hyperprolactinemia induce inhibition of gonadotropin secretion

Question 30

Postlactational involution

Answer 30

at waning, prolactin and oxytocin release not stimulated --> unremoved milk leads to increased acinar pressure --> lactation ceases within 7-10 days

Question 31

During postlactational involution, 80% of epithelium dies by ____

Answer 31

apoptosis

Question 32

Involution take ____ months and involves remodeling of tissues

Answer 32

3-4 months --> partiy leads to a permanent change in breast

Question 33

Hypoplasia/amastia

Answer 33

asymmetry common, underdevelopment uncommon --> secondary to biopsy, chest wall trauma, thoracic radiation in childhood

Question 34

Supernumerary nipples/polypastia

Answer 34

secondary to incomplete regression of milk streak

Question 35

Galactorrhea

Answer 35

persistent discharge of milk in absence of parturition; discharge in non-nursing mother > 6 months postpartum

Question 36

Diff Dx: Galactorrhea with hyperprolactinemia and amenorrhea

Answer 36

prolactinoma or drugs

Question 37

Dx: galactorrhea with normal prolactin and regular menses

Answer 37

excessive sensitivity of breast to prolactin

Question 38

Sheehan's Syndrom

Answer 38

infarction of pituitary during labor and delivery --> prone to decreased blood flow due to increased size during pregnancy

Question 39

Lack of postpartum milk production may be the first sign of ___

Answer 39

Sheehan's Syndrome

Question 40

Breast cancer risk: older age of menarche

Answer 40

increases risk

Question 41

Breast cancer risk: older age at menopause

Answer 41

increases risk

Question 42

Breast cancer risk: ovariectomy

Answer 42

reduces risk

Question 43

Breast cancer risk: postmenopausal obesity

Answer 43

increases risk

Question 44

Breast cancer risk:early first full term pregnancy

Answer 44

reduces risk