Breast Pathology Flashcards
Breast Embryology
Modified sweat gland, Derived from skin
Breast tissue (and pathology) anywhere along milk line, axilla to vulva
Breast Anatomy & Physiology
Duct-lobular-unit is functional unit
~ Glands produce milk
Both are lined by two layers of epithelium:
-Luminal cell layer (Produce milk)
-Myoepithelial cell layer (Contractile)
Breast tissue is hormone sensitive (receptors for E & P)
-Develop after menarche, esp RUQ
-Tender during menstrual cycle
-Hyperplasia during pregnancy
-Atrophy after menopause
Galactorrhea
Production of milk outside of lactation
Due to nipple stimulation, prolactinoma of anterior pituitary, or drugs
NOT a symptom of breast CA
Acute Mastitis
Breast-feeding creates small fissures, entry-way for Staph aureus
Warm, erythematous with PURULENT nipple discharge
Continue drainage/ breast-feeding
DiCLOXicillin
Complications: Abscess
Periductal Mastitis
Inflammation of subareolar ducts
Due to relative vitamin A deficiency (in smokers)
-SQ metaplasia of specialized epithelium of lactiferous ducts
-Duct plugged with keratin
-Duct inflamed
Subareolar mass with nipple retraction
-B/c heals with fibrosis
-B/c myofibroblasts contract, pull on skin
Mammary Duct Ectasia
***Not every mass in post-menopausal F is breast CA
Ectasia = Dilation of tubular structure
Subareolar mass with “GREEN-BROWN” discharge
Biopsy shows chronic inflammation with plasma cells
MultiPAROUS POST-meno women
Breast Fat Necrosis
Trauma related, patient may not recognize
Mass on exam OR calcification on MAM
Biopsy also shows GIANT CELLS
Fibrocystic Change
Benign, Most common change PRE-meno
Fibrotic CT + Cystic lobules/ducts
+/- Apocrine metaplasia
?Due to changes in E & P over time
Presents as “lumpy” breast, especially RUQ
Cysts have “blue-domed” appearance
Changes WITH Increased Risk for Invasive CA
Ductal hyperplasia (extra epithelium)
Lobular hyperplasia
Sclerosing adenosis (extra glands)
Intraductal Papilloma VS. Papillary Carcinoma
Benign
Growth in duct, still lined by two-layer epithelium
Bloody nipple discharge because vascular
Pre-meno women
C/c Papillary Carcinoma:
-Post-meno women (Incidence increases with age)
-No myoepithelial cell layer
Fibroadenoma VS. Phyllodes Tumor
-Benign, CT & glands
-Estrogen-sensitive***
-Marble-like, mobile mass
-Most common TUMOR pre-meno
-Benign/ malignant
-Fibroadenoma-LIKE tumor with leaf-like projections
-POST-meno women
Breast Cancer
Risk related to estrogen exposure
-Female sex
-Older age
-Early menarche/ late menopause
-Obesity
-Atypical hyperplasia
-First-degree relative with breast CA
Ductal Carcinoma In Situ
(DCIS)
VS.
Invasive Ductal Carcinoma (IDC)
Malignant proliferation of cells in duct
-NO MASS on exam
-Comedo-Type = High grade with necrosis and calcification on MAM (Central cells lose blood supply & die)
+/- Paget Disease of Nipple
-Erythema, ulceration
-Underlying CA
VS.
-WITH MASS, dimpled skin, nipple retraction
-Biopsy shows duct-like structures within desmoplastic stroma
Invasive Ductal Carcioma Special Subtypes:
Tubular
Produce tubules WITHOUT contractile cell layer, within desmoplastic stroma
Good prognosis
Invasive Ductal Carcioma Special Subtypes:
Mucinous
Malignant cells floating in mucus
Seen in elderly women
Good prognosis
Invasive Ductal Carcioma Special Subtypes:
Inflammatory
Biopsy shows tumor in dermal lymphatics
POOR prognosis
Ddx: Acute Mastitis (NO RESPONSE TO ABX)
Invasive Ductal Carcioma Special Subtypes:
Medullary
High grade malignancy
+Lymphocytes & plasma cells
Seen in BRCA1 mutation
Lobular Carcinoma In Situ (LCIS)
VS.
Invasive Lobular Carcinoma (ILC)
Malignant proliferation of cells in LOBULES
Dyscohesive, lack E-cadherin (Do NOT form ducts)
-No mass, found incidentally
-Multifocal & bilateral
-Rx TamOXifen!
VS.
-Cells grow & invade in “single-file”
Prognosis Based on TNM Staging
Metastasis - Most important factor, but not many patients present this way
Spread to axillary lymph node - Most useful factor in determining prognosis
Sentinel lymph node biopsy***
Predictive Factors
Predict response to treatment
1. Estrogen receptor
2. Progesterone receptor
3. HER2/Neu gene amplification
If tumor expresses ER & PR
-Respond to anti-E agents (TamOXifen)
If tumor has HER2/Neu amplification
(Growth factor receptor)
-Respond to anti-growth ab’s (TrastuzUMAB)
If tumor negative for all three predictive markers
-“Triple-Negative”
-POOR prognosis
Hereditary Breast Cancer
Multiple first-degree relatives with breast CA
Tumor at pre-meno age
Multiple tumors
Single Gene Mutations
-BRCA1: Breast & ovarian carcinoma
-BRCA2: Breast carcinoma in M
May opt for prophylactic mastectomy & breast reconstruction
Male Breast Cancer
Rare subareolar mass under nipple
Older males
Nipple discharge
Usually develop IDC (Male breast is mostly DUCTS, less lobules)
Associated with BRCA2 mutation & Klinefelter syndrome (XXY)
