Pathology of Pulmonary Neoplasia Flashcards
What is the aetiology of lung cancer?
- Tobacco (85%)
- Asbestos
- Environmental radon
What percentage of smokers get lung cancer?
10%
What molecules are found in tobbaco smoke?
Pro-carcinogens
what cells do procarcinogens have an effect on?
Epithelial cells
How does tobacco smoke cause cancer?
- Epithelial effects
- Multi-hit theory in carcinogenesis
- Host activation of pro-carcinogens - Inherited polymorphisms predispose (metabolism of pro-carcinogens, nicotine addiction)
Where are the two main stem cell populations in the lungs?
- Large arease of the bronchi
- Peripheral lung epithelium of the small bronchioles and the alveolar epithelium.
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 is adenocarcinoma found?
In the periphery of the lung.
Where is squamous carcinoma found?
Central parts of the lung
What are other types of cancer that are found in the lungs?
- Carcinoid Tumour
- Tumours of bronchial glands
- Lymphoma
- Sarcoma
- Metastases from somewhere else to the lung
What are the fpur main types of primary lung carcinoma?
- Squamous cell
- Adenocarcinoma
- Small cell carcinoma
- Large cell carcinoma
How are the four types of lung cancer catergorised?
- Small cell carcinoa is in one group
- All other types of cancer are in another group.
How does primary lung cancer grow?
It grows silently for many years, presents late in its natural history, may have few signs until the disease is very advanced. Symptomatic lung cancer is very fatal.
What are the local effects lung cancer?
- Bronchial obstruction (collapse, endogenous lipoid pneumonia, infection, abscess, bronchiectasis)
- Pleural (inflammatory, malignant)
- Direct invasion (chest wall)
- Direct Invasion (nerves: phrenic - diaphragmatic paralysis, L recurrent laryngeal: Hoarse + Bovine cough, Brachial plexus - Pancoat T1 damage, Cervical sympathetic - Horner syndrome)
- Mediastinum (SVC, Pericardium)
- Lymph node Metastatases (Mass effect and Lymphangitis carcinomatosa)§