Pathology of Lung Cancer Flashcards
What is the leading cause of lung cancer?
Tobacco
What are other other causes of lung cancer?
Asbestos Environmental radon Occupational exposure: chromate, hydrocarbons, nickel Air pollution Other radiation Pulmonary fibrosis
What are two important compounds in tobacco that are through to cause lung cancers?
Polycyclic aromatic hydrocarbons
N-Nitrosamines
What type of lung cancer are the N-nitrosamines thought to cause?
Adenocarcinomas in the periphery of the lungs
What type of lung cancer are polycyclic aromatic hydrocarbons thought to cause?
Squamous cell carcinoma in the central bronchi
What are the 3 effects of tobacco smoke that can lead to lung cancer?
Epithelial effects
Multi-hit theory of carcinogens
Host activation of pro-carcinogens
What is the multi-hit theory?
3-12 key significant changes must occur in cells that survive, and must occur in a specific sequence for tumour to develop
How can inherited polymorphisms predispose a person to developing lung cancer?
Metabolism of pro-carcinogens
Nicotine addiction
What type of cells are targets for carcinogens?
Stem cells
Describe the pathway of carcinogenesis in the lung periphery
Bronchioalveolar epithelial stem cell transforms - adenocarcinoma
Describe the pathway of carcinogenesis in the central lung airways
Bronchial epithelium stem cells transform - squamous cell carcinoma
Describe basic formation on the invasive bronchogenic carcinoma
- Squamous dysplasia in the epithelium of the bronchial tree
- Carcinoma in situ
- Has invasive potential allowing it to develop into an invasive carcinoma
Process strongly associated with smoking
Describe stages in development of peripheral lung adenocarcinoma
- Atypical adenomatous hyperplasia
- Adenocarcinoma in situ
- Invasive carcinoma
Can occur in non-smokers
What type of cancer can occur in non smokers?
Peripheral lung adenocarcinoma
What is the most common driver mutation in lung cancer?
KRAS
Name a driver mutation which is smoking induced?
KRAS
Name driver mutations which are not smoking induced?
EGFR
BRAF
HER2
ALK rearrangements
What is an addictive oncogene?
An oncogene that when inactivated will stop the growth of the cancer