7.1.2 Breast Cancer Flashcards
How common is breast cancer?
Most common cancer
1/7 women
Male breast cancer makes up 1% of all cases (increased risk with Klinefelter’s and trans women, as treated with oestrogen for prostate cancer)
What is the most common type of breast cancer?
95% adenocarcinomas
Where on the breast does cancer most commonly affect?
Upper outer quadrant
What are the risk factors of breast cancer?
BREAST
Breast feeding
Reproductive history, partity and age at first full term pregnancy
Exogenous oestrogens (HRT)
Age
Sex- female more likely
Time of menopause, later= more risk
What genes are involved in hereditary breast cancers?
10% of all breast cancers
BRCA1/2
p53 (Li-Fraumeni syndrome)
Tumour supressor genes- their proteins repair damaged DNA
How is breast carcinoma classified?
In sutu and invasive
Ductal or lubular
What is in situ carcinoma?
Neoplastic population of cells limited to ducts and lobules by byasement membrane
Myoepithelial cells are preserved
Does not invade into vessels, therefore cannot metastasis or kill patient
Why is ductal carcinoma in situ a problem?
Non-obligate precursor of invasive carcinoma
Presents as mammographic calcifications but can present as a mass
Can spread through ducts and lobules and can be very extensive
What is shown on histology of ductal carcinomas in situ?
Central (comedo) necrosis with calcification
What is Paget’s disease?
Cancer cells extend to nipple skin without crossing basement membrane
Causes a unilateral red and crusting nipple
Eczematous or inflammatory nipple should be investigated and biopsied to exclude pagets
Outline the features of invase carcinoma
Neoplastic cells invade beyond basement membrane into stroma
Can invade into vessels so can spread to lymph nodes and other sites
Usually presents as a mass or mammographic abnormality
By the time it is palpable patients normally have axillary lymph node metastases
What is Peau d’orange?
Involvement of lymphatic drainage of the skin
What are the different types of invasive breast carcinomas?
Invasive ductal carcinoma
Invasive lobular carcinoma
Other types- tubular, mucinous
(these have good prognosis, found often in older women)
Card showing normal breast tissue vs invasive ductal carcinoma
Normal breast
Invasive ductal carcinoma NST
What is this showing?
Invasive lobular carcinoma
What is this showing?
Mucinous carcinoma
How does breast cancer spread?
Via lymphatics, usually ipsilateral axilla
Distant metastases via blood vessels
Invasive lobular carcinoma can spread to odd sites- peritoneum, retropreitoneum, lemptomeninges
What is the most common site distant metastases spread to?
Bones
What is this showing?
Vascular invasion
What factors determine prognosis in breast cancer?
In situ or invasive
TNM stage
Tumour grade (1-3)
Histological subtype
Molecular classification and gene expression
How does grade effect survival?
Grade 1-90%
Grade 3- 40%
What is a gene expression profile?
Analysis of genes to identify marker genes
Those with these genes would eventually develop metastases
How many marker genes for breast cancer are there?
17
What is the triple approach for breast cancer?
Clinical
History
Family history
Examination
Radiographic imaging
Mammogram
USS
Pathology
Core biopsy
Fine needle aspiration cytology
What is the aim of mammoraphic screening?
Identify small impalpable cancers and pre-invasive cancers
Done every 3 years for women 47-73
What are the therapeutic approaches in breast cancer?
Breast surgery
Mastectomy
Axillary surgery
Use sentinel node sampling to decide whether to remove all nodes or just involved
Post-operative radiotherapy to chest and axilla
What is sentinel lymph node biopsy?
Intraoperative lymphatic mapping with dye and/or radioactivity of the draining lymph nodes
Sentinel or draining nodes are most likely to contain breast cancer metastases
If negative axillary dissection can be avoided
When is chemotherapy used?
If benefits thought to outweigh risks
If given before surgery= neoadjuvant (basically to shrink tumour size)
When is tamoxifen hormone treatment given?
Depends on the oestrogen receptor status, approximately 80% of cancer are oestrogen receptor positive (ER positive)
Give tamoxifen if positive for oestrogen receptors
When is herceptin hormone treatment given?
Depending on Her2 receptor status
(20% of cancers are Her2 positive)
If Her2 positive give Herceptin
What is herceptin and Her2?
Herceptin= transtuzumab
Monoclonal antibodies against the Her2 protein
Her2 is human epidermal growth factor receptor
How do we improve survival from breast cancer?
Early detection
Awareness
Neoadjuvant chemotherapy
Gene expression profiles
Prevention in familial cases e.g. prophylactic mastectomies
What are molecular classifications in breast cancer?
Learn this generally
(moved to last card so it doesn’t keep popping up while learning)
