Breast Flashcards
Breast in embryologically derived from_____
The skin. It is a modified sweat gland
Milk Line
Line from axilla to the vulva along which breast tissue can develop anywhere on that line
2 layers of epithelium in Lobulues and Ducts
Luminal Cell layer - inncer cell layer, milk production in lobules
Myoepthelial Cell Layer - Outer cell layer, contractile to propel milk to nipple
Indications that Breast tissue is hormone sensitive
1) After menarche see increase in estrogen and porgesterone and a corresponding increase in breast size and lobule formation
2) Breast are tender during menstrual cycle
3) During pregnancy undergo hyperplasia (E and P from corpus luteum, P from placenta, E from fetus and placenta workign together)
4) After menopasue breast tissue udnergoes atrohpy
Breast tissue is highest in which quandrant
upper outer quandrant
Galactorrhea
Milk production outside of lactation. Causes include nipple stimulation, prolactinoma of anterior pituitary, and drugs
Acute Mastitis
Bacterial infection of breast (staphylococcus aureus). Gain entry to breast usually after breast feeding. Breast is erythematous and purulent nipple discharge (can eventually get abscess formation. Encourage to continue breast feeding to treat in addition to antibiotic (dicloxacillin)
Periductal Mastitis
Inflamation of subareolar ducts. Usually seen in smokers since they get a Vitamin A deficiency that leads to squamous metaplasia of lactiferous ducts that can block and inflame the duct with their keratin.
See subareolar mass with nipple retraction
Mammary Duct Ectasia
Inflammation with dilation (ectasia) of subareolar ducts. Presents as sub areolar mass with GREEN BROWN NIPPLE DISCHARGE. Plasma cells on biopsy. See in multiparous, postmenopausal women
Fat Necrosis of Breast
Mass on physical exam or abnormal calcifications on mammography. Necrosis usually occurs due to trauma to the fat
Fibrocystic Change (Fibrosis, cysts, apocrine metaplasia) Ductal hyperplasia Sclerosing Adneosis Atypical hyperplasia
Development of fibrosis and cysts in the breast and is hormone mediated.
Presents as vague irregularity of the breast tissue (lumpy breast)
Cysts have a blue-dome like appearance on gross exam.
Benign but some are related to increased risk for invasive carcinoma in both breasts
Fibrosis, cysts, apocrine metaplasia - no increased risk
Ductal hyperplasia, Sclerosing Adneosis - 2 x risk
Atypical hyperplasia - 5 x risk
Intraductal Papillmoa (papilloma vs papillary carcinoma)
Papillary growth usually into a large duct. Characterized by by fibrovascular projection into duct. Classically presents as bloody nipple discharge.
Papilloma - fibrovascular projection lined by both epithelial and myoepthelial cells.
Papillary carcinoma - projection covered by ONLY epithelial cells, NO myoepithelial
Fibroadenoma
Tumor of fibrous tissue and glands. Most common benign neoplasm seen in premenopausal women. Well circumscribed, mobile, marble like mass that is estrogen senstive. No increased risk of carcinoma
Phyllodes Tumor
Fibroadenoma like tumor with overgrowth of the fibrous component, LEAF LIKE projections on biopsy. Seen in postmenopausal typically and some can be malignant
Risks for breast cancer
Female
Old age
Early menarche/late menopause/lack of pregnancy
Obesity
Atypical Hyperplase (usually driven by excess estrogen)
Hereditary (1st degree relatives with breast cancer = mother, sister, daughter)
Ductal Carcinoma in Situ (comedo type)
Malignant proliferation of cells in ducts with no invasion of basement membrane. Often detected as calcification in mammography (no mass). Need to biopsy since fat necrosis and fibrocystic changes can also display calcification. If it extends up the duct to involve the skin get paget disease (nipple ulceration and erythema)
Comedo type = high grade cells with necrosis and dystrophic calcification in center of ducts (since lack vasculature)
Paget Disease
Sign of DCIS> See nipple ulceration and erythema
Invasive Ductal Carcinoma
Invasive carcinoma that classically forms duct like structures. Most common breast cancer. Presents as 2cm mass or 1cm calcification. Advanced tumor can cause dimpling of the skin or retraction of the nipple.
includes the subtypes: tubular carcinoma, mucinous carcinoma, medullary carcinoma and inflammatroy carcinoma
Tubular Carcinoma.
IDC characterized by well differentiated tubules that lack myoepithelial cells. Good prognosis
Mucinous Carcinoma
IDC characterized by abundant extracellular mucin (tumor cells float in mucous pool) good prognosis and occurs in old women (70)
Medullary Carcinoma
IDC characterized by large, high grade cells growing in sheets with associated lymphocytes and plasma cells. Well circumscribed mass that can mimic fibroadenoma. Higher incidence in BRCA1. Good prognosis
Inflammatory Carcinoma
IDC characterized by carcinoma in dermal lymphatics. Presents as inflammed swollen breast with no discrete mass. Often mistaken for acute mastitis but doesnt improve with antibiotics or breast feeding. Poor prognosis
Lobular Carcinoma in Situ
Malignant proliferation of cells in lobules with no invasion of the basement membrane. No mass or calcifications so incidentally found on biopsy. See dyscohesive cells since they lack E-cadherin to bind them together. Often multifocal and bilateral. Treat with tamoxifen to reduce risk of subsequent cancer but low chance of developing into ILC
Invasive Lobular Carcinoma
Invasive carcinoma that typically grows in single-file pattern (dont form ducts because they lack e-cadherin to hold them together.
