FoM:L1 - Intro to cancer Flashcards
What is cancer?
a group of diseases characterised by unregulated cell growth and the invasion and spread of cells from primary site to other parts of the body
How do cancer cells differ from healthy cells?
- unstable DNA
- avoids normal cell death
How are benign and malignant tumours different?
malignant: uncontrolled proliferation of cells with the capacity to invade surrounding tissues and metastasise
benign: growth of cells that does not invade neighbouring tissues and cannot metastasise
What causes cancer?
- starts with damage to the DNA
- can be inherited
- environmental/lifestyle factors
- viruses
- natural cell processes and ageing
What is carcinogenesis?
- the process of a normal cell transforming into a cancer cell
What 3 things must a cell undergo before it becomes cancerous?
- Initiation
- promotion
- Progression
What are some risk factors for cancer that cannot be prevented?
- Age
- sex
- genetic factors
How does age impact risk of developing cancer?
- older age = higher risk
- as accumulation of DNA mutations
Outline cancers that are sporadic and cannot be inherited…
- mutations in cancer cells
- not in germline DNA
- not inherited
Outline cancers that are caused by inherited genetic susceptibility…
- mutation in germ cell
- inherited between generations
- increased lifetime risk of cancer
What are cancer predisposition gene syndromes?
high lifetime risk of certain cancers associated with germline pathogenic mutations in specific genes
What are the features of a genetic predisposition to cancer?
- mostly inherited in autosomal dominant faction
- characteristic groups of tumours with certain genes
- cancer at younger ages (typically)
- multiple family members affected
What are the modifiable factors that increase the risk of cancer?
- smoking
- alcohol
- obesity
- lack of exercise
- UV light exposure
- environmental exposures
What are some occupational and environmental exposures that can increase risk of cancer?
- asbestos; increased risk of mesothelioma
- agriculture; pesticides etc
- mining; silica
- construction
- radon gas
- air pollution
What are 2 examples of viruses that can cause cancer?
- HPV; cervical cancer
- Hep B and C; liver cancers
