Breast Histology Flashcards
What makes up the secretory tissue of the breast?
15-20 lobes, each consisting of tubuloacinar glands that drain via ducts to the nipple
What tissues make up the non-lactating breast?
Fibrous and adipose tissue surrounding the secretory lobules
Describe the duct system in the breast
Terminal ductules lead into intralobular collecting ducts that lead into the lactiferous duct for that lobe
The lactiferous duct leads to the nipple
How does the epithelium differ between large ducts and secretory acini?
Large ducts: columnar
Secretory acini: cuboidal
What type of epithelium lines the nipple?
Highly pigmented keratinized stratified squamous epithelium
Describe the changes that occur in the breast during the menstrual cycle
Epithelial cells increase in height
Lumina of ducts become enlarged
Small secretions appear
Describe the changes that occur in the breast if pregnancy occurs
Elongation and branching of smaller ducts
Proliferation of epithelial and myoepithelial cells
Plasma cells and lymphocytes infiltrate CT
Glandular tissue development
Secretory alveoli mature
What effect do oestrogen and progesterone have on secretory and adipose tissue?
Stimulate proliferation of secretory tissue
Fibro-fatty tissue becomes sparse
By what mechanism of secretion are lipid droplets of milk secreted?
Apocrine secretion: droplet buds off with a little bit of cytoplasm with it
By what mechanism of secretion are proteins of milk secreted?
Merocrine secretion: vesicle containing packaged protein releases only its contents
What is the lactiferous sinus?
An expanded duct region near the nipple that the lactiferous duct passes through
What pink cells surround the secretory epithelial cells in the lobule?
Myoepithelial cells
What is the basic functional secretory unit of the breast?
Terminal duct lobular unit
Describe the changes that occur in the breast if menopause occurs
Secretory cells of TDLY degenerate leaving ducts
In CT, reduced fibroblasts, collagen and elastin fibres
