Breast Pathology Flashcards
Describe the normal histology of the breast ducts
Secretory cells lining the inner lumen
Surrounded by myoepithelial cells
Surrounded by basement membrane
Describe the branching structure of the breast ducts
8-10 main ducts up the the nipple
Branch repeatedly in stroma
Terminal part empties into lobule composed of a group of acini
From what part of the breast tissue do most lesions arise?
Epithelium of the terminal duct lobular unit
What features are important on radiology?
Patterns of calcification (present in benign and malignant lesions)
Tissue density
Shape of lesions (many malignancies stellate in shape)
What are the 2 possible types of further investigation into a breast lesion, and what are the benefits and disadvantages of each?
Fine needle aspiration (FNA): collects a sample of cells to look for histological aspects of malignancy
Needle core/tru-cut biopsy: uses a larger needle to obtain a piece of tissue (usually ~1mm across, 1-2cm long), which allows the relationship of the cells to each other, the stroma and the basement membrane to be examined
What are the histological changes that occur with fibrocystic change?
Variable duct dilation +/- cyst formation (1 cyst may predominate) Fibrosis Adenosis (proliferation of acini structures) Apocrine metaplasia (pink, granular epithelial cells)
What is the presentation with fibrocystic change?
Asymptomatic
May produce lumps, discomfort
Bilateral and multifocal on examination/investigation
In what group is fibrocystic change common?
Women of middle to late reproductive years
Almost so common as to be considered physiological
What is fibroadenoma?
A solitary, well circumscribed benign mass, composed of neoplastic or hyperplastic stromal tumour with an epithelial component
In what group is fibroadenoma common?
Younger women
How does fibroadenoma usually present?
As a lump
What is the treatment for fibroadenoma?
Usually removed
What is the relationship between fibroadenoma and malignancy risk?
May be no or only slightly increased risk of malignancy
What is the most common cause of cancer-related death in Australian women?
Lung cancer
What is the most common cancer in Australian women?
Breast cancer
What is the average age of first diagnosis of breast cancer in Australia?
60
List 9 predisposing factors for breast carcinoma
Age (~70% of those diagnosed are over 50) Genetic factors (sporadic or inherited) Increased lifetime oestrogen exposure Less breast feeding Fewer pregnancies Obesity Alcohol Past history of certain breast diseases Other (e.g. ethnicity, radiation)
What type of genetic mutation is most commonly associated with breast carcinoma: sporadic or familial/germline?
Sporadic
List 4 common sporadic genetic abnormalities which predispose to breast carcinoma
p53
HER2
neu
c-erbB-2
What is the role of p53?
Involved in cell cycle arrest and DNA repair
What is HER2?
Proto-oncogene acting as an epidermal GF receptor
How does amplification of HER2 predispose to breast carcinoma?
An excess of HER2 receptors increases the response to GFs, causing increased cell proliferation
In what % of tumours is an amplification of HER2 present?
~20%
What % of breast carcinoma cases have 1 or more affected 1st degree relatives?
15-20%
What is the most common genetic abnormality in familial breast carcinomas?
Multiple low-risk susceptibility genes (cause cancer when they interact with environmental factors)
What % of cases have specific germline mutations in BRCA1, BRCA2 or p53?
5-10%