breast histology

Question 1

breast

Answer 1

Glandular organ located on the chest, the main function of the breasts is to make milk for breast feeding, structuarally the breasts are modified sweat glands, present in both sexes but only functional in the female, glandular, ductal connectivem adn adipose tissue, each gland is composedof 15- 20 lobes each drained by a lactiferous duct, each duct independenty drains in the nipple areola surrounds the nipple

Question 2

Mammary gland

Answer 2

prior to puberty the mammary gland of boys and girls has a similar structure, it consists of rudimentary lactiferous ducts grouped around the nipple, during puberty the mammary glands develop in females but their development is usually inhibited in males

In females under estrogen influence, adipose tissue accumulates in the breast, the duct system of the mammary gland branches and rudimentary lobules appear

Question 3

mature inactive gland

Answer 3

15-20 lobes (each with multiple lobules, lobes separated by CT and adipose tissue (interlobular CT- dense irregular CT and adipose, intra lobar CT with mast cells, macrophages, plasma cells, each lobe drained by a lactiferous duct- beneath the nipple the dialated lactiferous duct forms a lactiferous sinus a s a reseroir for milc, secretory units alveoli

The lactiferous duct has 2 layered epithelium, inner or luminal layer is cuboidal and the outer or bassal layer is a flattened myoepithelium, ducts are surrounded by loose CT and a capillary network

Question 4

Changes during pregnancy

Answer 4

during pregnancy, mammary gland proliferate and lobules enlarge as secretory acini sprout from the intralobar duct systems, mediated by high levels of estradiol progesterone, and growth factors

The septa become compresed as fibrous CT and adipose decrease, lobules now seem more comparable to the salivary glands, secretion of watery colostrum precedes the secretion of true milk, which does not come until after the birth of the child

Question 5

Lactation gland

Answer 5

Dramatic changes in the mammary gland occur during pregnancy, the ducts in the lobules proliferate and branch and secretory albelo sprout from them, estrogen stimulates alveolar and ductal growth, progesterone stimulates alveolar differentiation, alveoli/ acini are spheres of epithlial cells that become teh active milk secreting structures in lactation, the increase in glandular tissue is accompanied by a great decrease in the amount of CT and adipose

Question 6

Secretion of milk

Answer 6

Secretion of milk proteins preceeds by exocytosis (merocrine secretion) whereas lipid are secreted by apocrine secretion
Secretion is stimulated by suckling which inhibits PIH and increase prolactin 10-20x baseline, also initiates the milk ejection reflex via the seecretion of oxytocin from the neurohypophysis

Milk i sejected from the glandular tissue into th elactifeours sinuses, colostrum (has a high protein low lipin), The milk is 4% fat,and lots of sugar

Question 7

Involuted gland

Answer 7

in the absence of suckling/weaning, secretion of milk ceases and the mammary glands regress to the inactive (non lactating condition) fibrocollagenous CT replace adipose and encloses lobules

Question 8

fibroadenoma

Answer 8

non cancerous benign lump that is found in breast tissue, when felt under the skin, the lump may feel rubbery and easily moveable within the breast tissue, fibroadenomas are commonly found in young women during their reproductive years

Question 9

Breast cancer

Answer 9

the most common malignancy in women (2nd most common cause of death) 2 types
Ducatal and lobular

Question 10

Ductal hyperplasia

Answer 10

describes a proliferation of ductal cells

Ductal carcinoma- atypical ductal hyperplasia is similar to DH, but cells are anisocytosis (odd shape) and anisokaryocis (chromatin is lots)

Question 11

Lobuar carcinoma

Answer 11

in the cancer