What is Cancer? Flashcards
What is cancer?
Group of diseases characterised by uncontrolled proliferation and spread of abnormal cells
The abnormal cancerous cells do 3 things, which are what?
- Proliferate to form tumours
- Invade neighbouring tissues
- Spread through body to form distant tumours
What is a tumour?
Mass of tissue formed by growth of new cells
What are the classified terms for cancer according to the following tissues of origin?
- epithelial
- connective
- lymphoid
- blood
- epithelial = carcinoma
- connective = sarcoma
- lymphoid = lymphoma
- blood cells + blood forming cells = leukaemia
What is the commonest type of human cancer and why?
- Carcinomas
- Bc actively dividing cells
- Most exposed to external “insult”
What is the (4 stage) process that normal cells undergo, which is under tight control?
- Growth
- Maturation
- Perform function
- Cell death
What is different in cancer cells in terms of the normal cell life process?
- Increased cell growth + proliferation (in absence of stimuli)
- Decreased cell death
- Decreased cell maturation (“decreased differentiation”)
What is an adenoma?
Non-malignant tumour of glandular epithelium
What is a benign tumour?
- non-invase
- growth usually self-limiting
- some can develop into malignant cancers (most don’t)
- can be dangerous if it presses on a vital structure
What is the difference between benign and malignant?
- BENIGN = margins of tumour well-defined, growth entirely local
- MALIGNANT = margins poorly defined, cancerous cells extend into/invade/destroy surrounding tissues
What 3 characteristics are looked into when diagnosing cancer, in terms of histopathology?
- abormalities of cells (cytology)
- abnormalities of tissue structure
- evidence of invasiveness
What is meant by ‘metastases’?
- cancer becomes invasive, eats way through basement membrane
- local spread via lymphatic system to regional lymph nodes
- distant spread via blood circulation
- cancer cells establish new tumours in other parts of body called metastases
What are the commonest cancers diagnosied in the UK in men and women?
MEN = prostate, lung, colorectal, bladder
WOMEN = breast, colorectal, lung, ovary, uterus
What are the commonest causes of cancer death in the UK in 2010 in men and women?
MEN = lung, prostate, large bowel, oeseophageal
WOMEN = lung, breast, large bowel, ovary
What are risk factors for cancer?
- Age - inc # of mutations over time
- Chemical factors - cause mutations
- Physical factors - cause mutations
- Viral factors
- Hormonal factors - inc cell turnover -> inc mutation rate
- Genetics - defect in DNA repair
