Breast cancer Flashcards
What % of all malignancies are breast cancer?
20%
Incidence of breast cancer is increasing by what % each year?
1%
What is the lifetime risk of breast cancer for women in the UK?
1 in 9
How many people are diagnosed with breast cancer in the UK each year?
41,000
How many breast cancer deaths are there per year in the UK?
13,000
How many cases of male breast cancer are there in the UK per year?
300
Compared to the rest of the world, what are the mortality rates in the UK like?
One of the highest mortality rates in the world
What are the risk factors for breast cancer? (9)
- Age
- Geography
- Age at menarche (early) and menopause (late - after age 55 then risk doubles)
- Age at first pregnancy (late or nulliparity)
- Family history
- Exogenous oestrogens
- Diet (high fat intake, obesity and alcohol)
- Benign breast disease
- Radiation
What % of female breast cancer is due to inheritance of the mutated copy of BRCA 1 or 2?
5-10%
What % risk is posed to women with the mutated BRCA 1 or 2, by the age of 70 years?
87%
Which other genes are associated with contributing to familial breast cancer? (3)
- PTEN (Cowden disease)
- MSH1 or 2 (HNPCC)
- p53 (Li-Fraumeni syndrome)
What may be offered to women who are asymptomatic but who have a high risk of developing breast cancer due to inheritance of a mutated gene? (3)
- Prophylactic surgery (can reduce risk of breast cancer by 95%)
- Screening - MRI in women under 50 who are high risk, as mammography would not be useful
- Breast cancer-prevention trials - clinical trials used tamoxifen
In which breast is cancer more common?
Breast cancer is more common in the left breast
50% of breast cancers arise in which quadrant?
Upper outer quadrant
What is the commonest pathology for breast cancer?
Ductal carcinoma
What does DCIS mean?
Ductal carcinoma in situ
What % of breast carcinomas arise in the ducts?
90%
How does DCIS begin?
An atypical proliferation of ductal epithelium that eventually fills and plugs the ducts with neoplastic cells
How is the DCIS remain as such, as opposed to an invasive ductal carcinoma?
It is classified as a DCIS as long as the tumour remains within the confines of the ductal basement membrane
What % of DCIS will progress to invasive?
30-50%
How does DCIS appear on mammography?
An area of micro-calcification
What risk do lobular carcinoma in-situ carry?
They carry the risk of ipsilateral and contralateral invasion and typically they are not palpable nor contain micro-calcification
What % of breast cancers are invasive ductal carcinomas?
75%
What do the malignant cells of invasive ductal carcinoma (IDC) consist of?
Fibrous stroma (these can be dense, and then known as scirrhous carcinoma)
Where does the IDC tumour invade to?
Through the breast tissue into the lymphatics and vascular spaces, to gain access to regional nodes and the systemic circulation
What are the ‘sentinel’ or regional nodes associated with breast cancer?
Axillary (and less often internal mammary)
To which organs is breast cancer most likely to spread? (6)
- Bone
- Lung
- Pleura
- Liver
- Skin
- CNS
Which three features of the tumour are assessed to give a histological grade (I - III)?
- Tubule formation
- Nuclear pleomorphism
- Mitotic frequency
Immunocytochemistry commonly assess which two hormone receptor statuses in IDC?
Oestrogen and progesterone receptor status
If the breast cancer expresses the nuclear oestrogen receptor (ER), what does this mean in terms of prognosis?
It conveys a better prognosis, compared to ER-negative tumours
What % of breast cancers are ER-positive?
60-70%
What does ER-negative (oestrogen receptor status), relate to in terms of prognosis?
Not such a good prognosis as there is a higher risk of spread to lymph nodes and distant sites at presentation
Which other biological marker is used to predict prognosis and guide therapy?
HER2 - growth factor receptor gene
How is HER2 assessed?
By either immunocytochemistry or fluorescence in situ hybridisation (FISH)
What is HER2 associated with?
Aggressive behaviour, high risk lymph node involvement and haematogenous spread
What does triple negative breast cancer refer to?
These tumours do not express ER, PR (progesterone receptor) or HER2.