Pathology of Pulmonary Neoplasia COPY Flashcards
What is the most common cause of death by cancer?
Lung Cancer
What are the Aetiologies for lung cancer?
- Tobacco
- passive smoking
- Asbestos
- other occupational exposure (chromates, hydrocarbons, Nickel)
- air pollution
- Radiation (environmental radon
- Diesel exhaust
- pulmonary fibrosis
How much of lung cancer is attritable to tobacco?
Over 85%
What percentage of smokers get lung cancer?
10%
What percentage of non-smoking lung cancers are caused by passive smoking?
At least 25%
Why does tobacco smoke cause lung cancer?
- Epithelial effects
- Multi-hit theory in carcinogenesis
- Host activation of pro-carcinogens
- Inherited polymorphisms predispose to metabolism of pro-carcinogens, nicotine addiction
How does adenocarcinoma arise in the lung?
Bronchoalveolar epithelial stem cells transform
How does squamous cell carcinoma arise from?
Bronchial epithelial stem cells transform
Where about do you see adenocarcinoma and squamous cell carcinoma?
Adenocarcinoma - Lung periphery
Squamous cell carcinoma - Central lung airways
Which oncogene is activated by smoking?
KRAS
What are the other important oncogenes that give rise to lung cancer?
EGFR BRAF HER2 ALK rearrangements
What are the common tumours of the lung?
- Carcinoid tumour (less than 5% of lung neoplasms, low grade malignancy)
- Benign causes of mass lesion
- Tumours of bronchial glands (V RARE, adenoid cystic carcinoma, mucoepidermoid carcinoma, benign adenomas)
- Lymphoma
- Sarcoma
- Metastesis to lung are common
What are the 4 main types of lung cancer?
- Squamous cell
- Adenocarcinoma
- Small cell carcinoma
- Large cell carcinoma
What is an adenocarcinoma in situ?
Bronchioalveolar cell carcinoma (subtype of adenocarcinoma)
What are carcinoid tumours?
Rare cancer of neuroendocrine system (system that produces hormones)
Tumour usually grows in bowels or appendix, can be found in stomach, pancreas, lung, breast, kidney, ovaries, testicles.
Grows very slowly
What is the difference in incidence between Small cell carcinoma and Non-small cell carcinoma
Small cell carcinoma - 15%
Non-small cell carcinoma - 85%
(Non-small cell carcinoma - adenocarcinoma, squamous cell carcinoma, large cell carcinoma)