Breast Flashcards
• What does the breast consist of?
o ductal mammary gland tissue in F (M rare)
o Adipose, CT (collagen and elastin)
o Ligamentous tissue (Cooper’s ligs)
o Mamm:fat = 1:1 (non-lactating), 2+:1 (lactating)
• What is ductal mammary gland tissue?
o modified sweat glands capable of producing and secreting milk during lactation
o lactiferous duct system (& lobules): 4-18 modified ducts, each has own opening at nipple
o cell lining: committed stem cell in terminal duct → myoepthelial cells and luminal cell types
o luminal: in lobules and terminal ducts make milk; no milk in large ducts
o myoepithelial cells: milk ejection, structure
• where does lymph from breast flow to?
o 75% to axillary LNs (pectoral, sub-scapular, humeral)
o Rest to para-sternal, abdominal LNs, and to the other breast
o Also internal mammary nodes
• What are the breast perimeter landmarks?
o Important in CBE!
o glandular tissue has 4 quadrants (upper outer, upper inner, lower outer, lower inner) and central sub-areolar
o Superior: clavicle
o Inferior: beyond infra-mammary crease
o Medial: sternal border
o Lateral: beyond the lateral breast fold (mid-axillary line), into axillary pectoral fascia and fat pad
• Describe the development of breast tissue?
o pre-pubertal: ductal system ends in terminal ducts w minimal lobule formation, little stromal tissue
o after menarche: terminal ducts → lobules, ↑volume of interlobular stroma.
o → CT tends to wrap concentrically around ducts and lobules
o 3rd decade: lobules and CT normally begin to gradually involute
o After menopause: lobules almost totally disappear, interlobular stroma replaced by adipose, ↑ density of loose CT
• How do mammograms look with age? Histology?
o When stroma is replaced by adipose tissue the breast more radiolucent.
o Younger: more radiopaque
o Older: adipse more radiolucent, so calcifications/tumors easier to detect
o Histo: younger has more CT stroma, older more adipose; pregnancy: much less stroma, mostly ductal
• What effects do E and P have during menstrual cycle?
o E: epithelial cell proliferation, duct elongation and branching, ↑volume and elasticity of CT and ducts, ↑ deposition of adipose
o P: ↑lobule formation, ↑ size of acini, lumen and ducts
• What are the breast tissue changes during the menstrual cycle (by day)?
o 3 - 7: ↑E → epithelial cell proliferation
o 8 - 14: E promotes differentiation of epithelial cells
o 15 - 20: ↑P → ↑size of acini, lumen, ducts
o 21 - 27: Intralobular stromal edema and venous congestion
o 27 - 30: ↓ E&P → ↓stromal edema and lumen size
• What are the breast tissue changes with pregnancy?
o usu begin at time of first missed menstrual period (gestational week 4)
o dt P, E, prolactin and placental lactogen secretion in 3rd tri
o breast tissue reaches complete morphological maturation and full functional activity
o At full term, breast is composed almost entirely of lobules, separated by a little CT
o Montgomery tubercles ↑ in # size
o 1st tri: proliferation of acinar cells, minimal secretory changes. Involution of stroma
o 3rd tri: intense lobular proliferation. cells appear enlarged, ↑ cytoplasm, enlarged nuclei. dramatic stromal involution
• What happens to breast tissue during lactation?
o Intralobular ducts form buds, secretory alveoli, grape-like clusters, scant stroma; glands have dilated lumina, lipid secretory vacuoles
o ↑ # lobules and acini in each lobule. ↓ inter/ intra-lobular stroma
o Myoepithelial cells are present but difficult to identify
o Luminal epithelial cells are secretory and have cytoplasmic vacuoles (to sustain lactation)
o Crying or suckling → hypothalamus → oxytocin → contraction of myoepithelial cells →expel milk
o Stop nursing: ↓ prolactin, ↓ milk; lobules involute over several months, infiltrated by lymphocytes and plasma cells
• What are Montgomeryt ubercles?
o Visible bumps of Glands of Montgomery
o =sebaceous glands in the areola, and nipple itseld
o Keep nipple lubricated and protected
o more pronounced during pregnancy, more apparent as nipple is stimulated
o overlying skin is smoother than rest of areola
• what are the terms for congenital breast conditions?
o Amastia= breast tissue, nipple, areola, absent; usu congenital or iatrogenic (drug or toxin induced)
o Amazia= mammary gland tissue absent, but nipple and areola present; congenital or iatrogenic
o Athelia= presence of breast glandular tissue but no nipple or areola; congenital, with progeria (premature aging)
o Poland Sequence: UL afflictions: athelia, defect pec mm, finger webbing
o Ectodermal dysplasia: BL athelia, abn skin, sweat glands, dry eyes, teeth
• What is supernumerary nipple?
o = 1+ additional nipples
o 2-6% F, 1-3% M
o Location: mb on breast; MC along milk line (extends BL axillae to groin)
• What is supernumerary breast tissue?
o Aka polymastia; presence of breast tissue in an ectopic location
o Established during development, but mb not apparent until puberty, or pregnancy and lactation
o Usu along milk line, rare elsewhere (foot)
o can undergo same pathologic changes as normal breasts- benign cystic changes, benign breast tumors (adenoma and fibroadenoma)
o consider polymastia if mass along milk line
• what is an inverted nipple?
o retracted into breast tissue rather than protruding outward
o usu dt fibrous bands that tether nipple in inverted position
o st will protrude if stimulated, st remains inverted; can still breast feed
o st begins with pregnancy, may return to normal when stop lactating
o ~3% of all women, 90% BL; 50% familial
o Must r/o breast CA if no other known cause
• What is galactorrhea?
o spontaneous flow of milky nipple d/c, in absence of childbirth or lactation
o mb dt local causes (excessive nipple stimulation); mc hormonal dysregulation
o LC (7%) presenting sx of underlying breast cancer in F < 60 (30% in > 60)
o Be concerned: UL, from 1 milk duct, serous-sanguineous (bloody), breast mass
o Assoc w ↑ prolactin (pituitary adenoma, med se, hypothyroid, endocrine anovulatory syndromes)
o Drugs: OCP’s, methyldopa, TCAs
o Also: solitary duct papilloma, breast cysts
o d/c w/o mass mb CA: 50% invasive carcinoma, 50% carcinoma in situ
• what is mastitis? Acute?
o Aka recurrent sub-areolar abscess or squamous metaplasia of lactiferous ducts
o inflammation of parenchyma of mammary gland (usu non-infx)
o usu lactating F = puerperal mastitis; anyone else = non-puerperal mastitis
o acute: Usu sterile, non-infx inflam; If infx: usu Staph aureus or Strep epidermitis; via cracks, fissures in nipple
• what is periductal mastitis? Micro appearance?
o usu painful mass in sub-areolar, w erythema
o st in M; > 90% are smokers; Nipple inversion mb sequelae
o micro: keratinizing squamous epithelium in duct system of nipple, extends to abn depth; chronic granulomatous inflammatory response; mb Dilation and rupture of involved ducts
• what is mammary duct ectasia? Ssx? Cause? Micro?
o dilatation (widening) of sub-areolar (lactiferous) ducts; seen on US
o mc 5th-6th decade, usu multiparous F; incidence ↑ w age
o usu UL; st mistaken for carcinoma by palpation and mammography
o ssx: cyclic and non-cyclic breast pain; st erythema; Palp, poorly defined areolar or peri-areolar mass; Thick nipple d/c; nipple inversion 30-40% (dt fibrosis)
o Cause: mb peri-ductal inflam
o Micro: dilated lactiferous ducts filled w granular debris, foam cells, Peri-ductal and interductal inflammation w infiltrate Ls and M0s macrophages, ↑ plasma cells
• What is Fibrocystic breast disease? Ssx?
o MC breast do, > 50% all breast surgeries
o fibrous lumps (cobblestone texture) and cords in breast tissue, non-cancerous
o 30-60% of F
o Lumps: smooth, defined edges, mobile; st obscured by assoc irregularities; mc upper outer quad
o Mb asx; or periodic pain/swelling dt hormones, menstrual cycle, life style
• How is fibrocystic dz dx?
o Usu dx 20-40; uncommon before adolescence; rare after menopause
o Clinical, PE usu sufficient, st need bx: fibrosis, sclerosing ductal epithelial proliferation (inwards), adenosis (ducts enlarged, full of glands), apocrine metaplasia; cysts fluid filled
o Usu not mammo, tissue too dense
o Fine needle Aspiration to drain larger cysts
• How is fibrocystic dz shown to be benign?
o Myoepithelial cells are present
o cytologic features of ductal cells vary depending on location within duct. ductal cells growing next to native myoepithelial/basal lamina zone
• what is Fat necrosis of the breast?
o Usu F, especially if breast is heavy and pendulous
o Mc dt prior breast trauma (seat belt), surgery
o Dt rupture of adipocytes and hemorrhage
o → lipolysis, FAs, glycerol
o → fibrosis, ↑ vascularization may wall off area
o → Calcification, hemosiderin deposition
• How does breast fat necrosis present?
o may appears as pnless breast mass, skin thickening, breast tissue retraction
o may look like malignant neoplasm
o mammo: central radiolucent area of fat, ↑density, calcifications at fat periphery
o typical: lucent-centered calcifications
o rule: do bx if CA possible from mammo
