Lung Cancer Flashcards
What does survival depend on?
- How big the tumour is
- What it has invaded locally
- Distant spread to other nodes and tissues
What system is used to stage lung cancer?
TNM system
Survival rate of stage 1 lung cancer?
More than 55% will survive their cancer for 5 years or more after diagnosis
Survival rate of stage 2 lung cancer?
Around 35% will survive their cancer for 5 years or more after
What % of lung cancers are operable?
Unfortunately, only a small percentage of patients with lung cancer are operable by the time they are diagnosed.
This is approximately 20%.
Why does lung cancer have such a poor prognosis?
Presents late
What is the respiratory epithelium?
A type of ciliated columnar epithelium
What can happy if the bronchial epithelium are irritated e.g. cigarette smoke?
To adapt, they change into a stronger epithelium e.g. squamous –> this is called squamous metaplasia
What is squamous metaplasia?
Squamous metaplasia is a benign non-cancerous change (metaplasia) of surfacing lining cells (epithelium) to a squamous morphology.
If the irritation of the respiratory epithelium continues, what can occur?
- Damage to genetic materials within cells (body can deal with this via apoptosis or immune surveillence)
- Sometimes a neoplastic cell will develop (can avoid body checks)
- This can independently proliferate –> dysplasia
- N.B. still above basement membrane
- This can independently proliferate –> dysplasia
If the dysplasia of respiratory epithelium continues, what can occur?
- Part/whole of epithelium can be replaced by neoplastic cells
- Part: low grade dysplasia
- Whole: high grade dysplasia or carcinoma in situ
What is ‘intraeptihelial neoplasia’?
Neoplastic cells on the epithelium but still above basement membrane
When can intraepithelial neoplasia become invasive?
When they develop the ability to invade through the basement membrane
What are the 2 main types of lung cancers?
- Non-small cell lung cancer (NSCLC): 80-85% of lung cancers
- Small cell lung cancer (SCLC) - 10-15% of lung cancers
N.B. mixed types are not unlikely
What are the 3 main types of NSCLC?
- Adenocarcinoma
- Squamous cell carcinoma
- Large cell carcinoma