Pathoma CH. 16 Breast Pathology Flashcards
Where are breast derived from embryologically?
From the skin—modified sweat glands
What is the functional unit of the breast?
Terminal duct lobular unit
What are the two epithelia lining the lobules and ducts of the breast?
Luminal cell layer
Myoepithelial cell layer
What is the liminal cell layer of the breast responsible for?
Milk production
What is myoepithelial cell layer of the breast responsible for?
Propels milk toward nipple
What occurs during pregnancy to the breast lobules and what drives this?
Hyperplasia—driven by estrogen and progesterone produced by the corpus luteum, fetus and placenta
What occurs to breast tissue after menopause?
Atrophy
Milk production outside of lactation…
Galactorrhea
Name 3 causes of galactorrhea…
Nipple stimulation
Prolactinoma of the anterior pituitary
Drug side effect
Bacterial infection of the breast caused by staphylococcus aureus and is associated with breastfeeding…
Acute mastitis
A breast feeding mother presents with erythematous breasts with purulent discharge from the nipple. Cultures are taken and staphylococcus aureus is found to be causing the infection. What is the most likely diagnosis?
Acute mastitis
What is the treatment for acute mastitis?
Continued drainage and antibiotics→ dicloxacillin
A 35 year old female patient presents with a subareolar mass and nipple retraction. She has a 15 year history of smoking and is found to have vitamin A deficiency. What is the most likely diagnosis for this patient?
Periductal mastitis→ inflammation of the subareolar ducts
Vit A deficiency→ squamous metaplasia of lactiferous ducts—blocking ducts causing inflammation
A postmenopausal women presents with a periareolar mass, green-brown nipple discharge and biopsy shows chronic inflammation with plasma cells. What abnormality is this patient most likely presenting with?
Mammary duct ectasia→ inflammation with dilation (ectasia) of the subareolar duct
30 y/o female patient presents with palpable mass upon breast examination. Abnormal calcification in seen on mammography and the biopsy shows calcifications and giant cells. What is the most likely diagnosis?
Fat necrosis→ most likely due to trauma—patient doesn’t always report trauma. Necrotic fat is also seen on biopsy
What is the most common abnormality occurring to the breast seen in premenopausal women?
Fibrocystic change—development of fibrosis and cysts
What is the presentation for fibrocystic change of the breast both on physical exam and gross exam?
PE—irregularity of the breast tissue in upper outer quadrant (lumpy breast)
Gross exam—Blue-dome appearance
What are the 3 different types of fibrocystic change that happen to the breast and their relative risk of developing invasive carcinoma?
1) Fibrosis, cysts, and aprocrine metaplasia→ NO risk
2) Ductal hyperplasia and sclerosing adenosis→ 2x increased risk
3) Atypical hyperplasia→ 5x increased risk
A 30 y/o women presents with bloody nipple discharge. Upon biopsy, fibrovascular projections lined by epithelial and myoepithelial cells are found. What is the most likely diagnosis for this patient and what does this diagnosis need to be differentiated from?
Intraductal Papilloma→ must be differentiated from papillary carcinoma because that too presents as bloody discharge.
How is intraductal papilloma distinguished from papillary carcinoma?
They both present as bloody discharge from the nipple and have fibrovascular projections lined by epithelial cells→ however, Intraductal papilloma presents with underlying myoepithelial cells—whereas carcinoma does NOT—also presents most commonly in premenopausal women and carcinoma increases with age—therefore is most commonly seen in postmenopausal women.
What is the most common premenopausal benign neoplasm of the breast?
Fibroadenoma