Benign Breast Pathology Flashcards
Describe the cytological rating system for breast tissue
Coded from C1 to C5
C1: inadequate sample, C2: benign, C3: atypia, C4: suspicious of malignancy, C5: malignant
Describe normal breast histology
Ductal lobular system lined by inner glandular epithelium
State the symptoms of acute mastitis
Painful, red breast, fever
Describe the pathophysiology of lactational acute mastitis
Polymicrobial staphylococcal infection due to cracks in the nipple
Describe the pathophysiology of non-lactational acute mastitis
Keratinising squamous metaplasia block lactiferous ducts leading to peri-ductal inflammation and rupture
Describe the cytology of lactational acute mastitis
Abundance of neutrophils
Describe the management of acute mastitis
Antibiotics +/- surgical drainage
If present, treatment of duct ectasia
State the biggest risk factor for mammary duct ectasia, and at least one other risk factor
Main: Smoking
Others: multiparity, age 40-60
Define mammary duct ectasia
Inflammation and dilatation of large breast ducts causing a poorly defined palpable periareolar mass with thick, white nipple secretions
Describe the cytology of mammary duct ectasia
Proteinaceous material and macrophages
Describe the pathophysiology of mammary duct ectasia
Diltation in one or more of the larger lactiferous ducts, which then fill with a stagnant brown or green secretion. The secretion irritates the surrounding tissue leading to periductal mastitis or abscess and fistula formation.
Define breast fat necrosis
Inflammatory reaction to damaged adipose tissue
Describe the clinical presentation of breast fat necrosis
Painless breast mass or skin thickening (can cause skin tethering or nipple retraction). May be identified on mammogram screening.
State at least 3 causes of breast fat necrosis
Trauma, radiotherapy, surgery, nodular panniculitis
Describe the histology of breast fat necrosis
Empty spaces, histiocytes, giant cells
Describe the clinical presentation of fibroadenoma
Painless breast lump - spherical, freely mobile, rubbery, variable size
Describe the histology of fibroadenoma
Multinodular mass of expanded intralobular stroma
Describe the cytology of fibroadenoma
Branching sheets of epithelium, bare bipolar nuclei, and stroma
Define fibroadenoma
Benign tumour from the overgrowth of collagenous mesenchyme, often multiple and bilateral
Define duct papilloma
Benign papillary tumour arising within the duct system of the breast
Describe the clinical presentation of duct papilloma
Bloody discharge
Describe the cytology of duct papilloma
Discharge cytology shows branching papillary groups of epithelium
Describe the histology of duct papilloma
Papillary mass within a dilated duct lined by epithelium
Define radial scar
A benign sclerosing lesion of central scarring surrounded by proliferating glandular tissue in a stellate pattern
State two benign conditions which mimic breast cancer on mammography
Radial scar, mammary duct ectasia
Describe the histology of radial scar
Central, fibrous, stellate area
Define Phyllodes tumour
Tumour of the interlobular stroma with increased cellularity and mitoses. Can be low or high grade
When and how does Phyllodes tumour present?
Age >50 years with a palpable mass
Name three proliferative benign breast lesions
Usual epithelial hyperplasia, flat epithelial atypia, in situ lobular neoplasia
Describe usual epithelial hyperplasia
Growth of glandular tissue and epithelial cells forming fronds, not considered a precursor to cancer (although slightly increased risk)
Describe flat epithelial atypia
Multiple layers of epithelial cells with more regular, round lumens with punched out areas. 4x increased risk of cancer
How much does in situ lobular neoplasia increase the risk of breast cancer?
7-12x
Describe the histology of in situ lobular neoplasia
Solid proliferation of aplastic cells with little space and small residue areas of lumen
