breast histology nl and benign Flashcards
lymphatic drainage of breast
axillary, supraclavicular and mediastinal lymph node
cell type of nipple and ducts
The keratinizing squamous epithelium of the overlying skin dips into the orifices at the nipple and then abruptly changes to a double-layered cuboidal epithelium lining the ducts
histology of breast stroma
The interlobular stroma consists of dense fibrous connective tissue admixed with adipose tissue. 2. The intralobular stroma envelopes the acini of the lobules and consists of breast-specific hormonally responsive fibroblast-like cells admixed with scattered lymphocytes
male breast vs female breast
Male breast contains no tubulues (acini). The breast consists of ductal structures surrounded by a small amount of adipose and fibrous tissue
breast structure during childhood
female breast is composed of branching ductal system without the lobular units.
breast structure at puberty
E and P stimulate proliferation of glandular tissue. Lactiferous ducts and interlobular duct system are stable. terminal duct lobular units undergo changes with hormone levels. The lobules are quiescent during first half of menstrual cycle, then cell proliferation and number of acini per lobule increases after ovulation. The intralobular stroma also becomes markedly edematous. Upon menstruation, the fall in estrogen and progesterone levels induces the regression of the lobules and the disappearance of the stromal edema.
breast structure during pregnancy
by the end of the pregnancy the breast is composed almost entirely of lobules separated by relatively scant stroma .
physiology of breast following cessation of lactation and menopause
cessation of lactation: involution in 3 m. Epithelial cells undergo apoptosis, lobules regress/atrophy. menopause: involution of TDLUs, duct system remains, dec interlobular stroma, inc fatty tissue
Sites of accessory nipples/ breasts
nipples: along milk lines- from armpit, through nipples along abdomen. Breasts: may be seen in the lower axilla where it may raise a concern for metastatic cancer.
Causes of gynecomastia
Absolute or relative increase in estrogen, Idiopathic ? , liver disease, drugs (dilantin, digitalis, marijuana), testicular tumors, metabolic or endocrine disorders
gynecomastia histology
ductal epithelial hyperplasia, stromal edema, and loose fibrosis around ducts.
who is affected by acute vs chronic mastitis
acute: young women, onset of lactation. Chronic: perimenopausal women
acute mastitis pathophys
Cracked or inflammed nipple permits entry of organisms > proliferation of bacteria (staph) in stagnant milk > acute inflammation (neutrophils) > acute abscess formation
Acute mastitis treatment and ddx
antibiotics, drainage of pus. Differential diagnosis includes inflammatory breast carcinoma
Chronic mastitis pathophys
Duct obstruction by secretions or cells. Dilation of ducts > stasis of secretion and epithelial debris > infiltration by lymphocytes/ plasma cells causes plasma cell mastitis. Duct rupture with release of lipid contents causes infiltration by foamy histiocytes and granulomatous mastitis. Both processes lead to irregular fibrosis and a painless fixed mass that mimicks carcinoma
periductal mastitis sx and associations
Women, and sometimes men, present with a painful erythematous subareolar mass that clinically appears to be an infectious process. More than 90% of the afflicted are smokers. This condition is not associated with lactation, a specific reproductive history, or age. May be due to fistula tract under smooth muscle of nipple.
fat necrosis- cause, gross appearance, microscopic appearance, differential diagnosis
Cause: ? ischemia, trauma. Gross: ill defined mass. Microscopic: - early: necrotic fat cells, neutrophils - later: macrophages, gc, fibrosis, Calcifications. Diff dx is cancer: hard irregular mass on palpation and mgm.
List benign neoplasms of breast
Fibroadenoma, Lactating adenoma, Phyllodes tumor, Papilloma
fibroadenoma of breast- gross appearance, origin, histology
Round, sharply demarcated, rubbery, mobile, 2-4cm, usually solitary. Origin: TDLU. Mixture of fibrous tissue & ducts in varying ratio. (Epith:2-cell layer or more)
lactating adenoma- when does it occur, gross appearance, microscopic appearance
Presents during pregnancy or lactation. Gross: circumscribed soft mass. Micro: proliferation of small tubular structures with lactational changes
Phyllodes tumor- gross appearance, micro appearance, spectrum,
Large fleshy tumors composed of intralobular stroma and ductal epithelium.. Leaf like processes into cystic spaces. Benign epithelium, fibrosarcomatous stroma. Spectrum: benign, low grade, high grade
Intraductal papilloma- gross appearance, micro appearance, ddx
Benign, 1cm mass, subareolar. Bloody nipple discharge. Gross: Papillary mass in a large duct. Micro: Delicate papillae, fibrovascular core, 2-cell layer of epithelium. Differential diagnosis: papillary Ca
Describe fibrocystic change
group of morphologic changes that often produce palpable lumps and which are characterized by various combinations of cysts, fibrous overgrowth, and epithelial proliferation. Cause is unknown, may be hormonal.
Fibrocystic change sx
•Asymptomatic, pain, nodularity. Range: Innocuous to pre-malignant
