Normal breast and Benign disease Flashcards
Where does the majority of the breast cancer spread to?
Where do cancers that arise on the medial aspect of the breast spread to?
Axillary node
Mediastinal LNs
functional unit of the breast
- what does it branch into?
terminal duct unit (smallest branch)
- stops branching into more ducts, but ends up in a cluster of small tubules (acini) and becomes the terminal duct lobular unit
- area where most of the changes occur that can malignant or premalignant
What area of the breast does the majority of malignant or premalignant changes occur?
Terminal duct lobular unit
The entire ductal system is lined by?
Two cell layers
- Outer: myoepithelial layer - contractile properties important in propelling milk in lumen, and supports inner layer
- in case of malignancy, myoepithelial layer is lost - Inner: epithelial layer - production of milk - single cuboidal epithelium
- any change in two cell layer is pathological
Difference between stroma lining the terminal duct lobular unit and the stroma between the lobules
INTRAlobular stroma: specialized stroma (also fibrous) that is hormone responsive
INTERlobular stroma:
regular fibrous tissue liek any where else in body
Diff between male and female breast?
Same until puberty
- then females develop lobules (+ TDLU)
- both have ducts and stroma
At puberty, what stimulates the lobules to grow?
E + P
- formation of actual lobules occur
During the menstrual cycle, what happens to breast development?
Increased size/nodularity of lobules
What happens to breasts during pregnancy?
Maximum stimulation with hormones:
1. epithelial vacuolization
- LOTS more acini
Entire lobule increases in size
- secretion in lumina
- Epithelial cells start increasing milk prod.
- Continues to be in this state during lactation and regresses when finished
What happens to breast tissue during menopause?
Involution of TDLUs
Duct system remains
Decrease in interlobular stroma
More fatty tissue comes in
Sites of ectopic breast tissue
Usually along midline (during development of fetus)
- most prominant is in the axilla
Juvenile hypertrophy
doesnt stay in nl range
- results in really large breasts –> discomfort
In gynecomastia, what proliferates?
mostly the stroma
Inflammatory lesions
- acute mastitis
- chronic mastitis
- periductal mastitis
- fat necrosis
Acute mastitis
young female - common in lactating breast
Cracked or inflammed nipple allows entry of staph and grows in milk in ducts
–> neutrophils come in –>
abscess forms
- can resemble cancer
Chronic mastitis
Perimenopausal women Nonbacterial inflammation due to duct obstruction --> Dilation of duct (duct ectasia) PLasma cell mastitis Granulomatous mastitis Healing by fibrosis
Periductal mastitis
aka recurrent subareolar abscess, squamous metaplasia of lactiferous ducts, Zuska disease
recurrent subareolar abcess
Painful erythematous subareolar mass
- 90% are smokers
- instead of having the double layered cuboidal epithelium, the outer squamous cells advance into the ducts
Fat necrosis
- Benign or malignant?
- Cause?
- Microscopic
Benign
Caused by ischemia or trauma
Ill defined palpable mass - mimics carcinoma
Microscopic:
early: necrotic fat cells, neutrophils
later: macrophages, glycoproteins, fibrosis Ca2+
Benign neoplasms o the breast
- Fibroadenoma (most common
- Lactating adenoma
- Phyllodes tumor
- (Intraductal) Papillloma
Fibroadenoma
derived from TDLU
- very well circumscribed
- mobile
- terminal ducts become squished by fibrous tissue
- NOT proliferating
Lactating adenoma
presents in pregnancy or lactation
- assoc. w/ rapid increase in size during pregnancy
soft circumscribed mass
Small tubular structure with lactational changes
Phyllodes tumor
large fleshy tumors
“leaflike projections” into cystic spaces
Spectrum: benign –> high grade
Most common in 5th decade
- some can become malignant
Which if the benign breast tumors can become malignant?
Phyllodes tumor
Intraductal papilloma
benign, 1 cm, subareolar (beneath areola) - papillary mass in large duct
Bloody nipple discharge (rule out carcinoma)
