Pathology of Lung Cancer

Question 1

Aetiology of lung cancer

Answer 1

• Tobacco
• Asbestos
• Environmental radon
• Other occupational exposure
  ~ Chromates, Hydrocarbons, Nickel
• Air pollution and Urban environment
• Other radiation
• Pulmonary fibrosis

Question 2

What are the 2 main pathways of carcinogenesis in the lung?

Answer 2

IN THE LUNG PERIPHERY
- Bronchioloalveolar epithelial stem cells transform
- Adenocarcinoma

IN THE CENTRAL LUNG AIRWAYS
- Bronchial epithelial stem cells transform
- Squamous cell carcinoma

Question 3

What is primary lung cancer?

Answer 3

• Probably grows ‘clinically silent’ for many years
• Presents LATE in its natural history
• May have few, if any, signs or symptoms until the disease is very advanced
• May be found incidentally, during investigation for something unrelated
• Generally speaking, symptomatic lung cancer is fatal

Question 4

Lung cancer: local effects

Answer 4

• Bronchial Obstruction :
  
  • Collapse
  • Endogenous Lipoid Pneumonia
  • Infection / Abscess
  • Bronchiectasis
• Pleural
  
  • Inflammatory
  • Malignant
• Direct Invasion
  
  • Chest Wall
• Lymph Node Metastases
  
  • Mass effect
  • Lymphangitis carcinomatosa

Question 5

Distant effects of lung cancer

Answer 5

• Distant Metastases : Liver, Adrenals, Bone, Brain, Skin
• Secondary to local Effects : Neural, Vascular
• Non- Metastatic Effects

Question 6

Non-metastatic paraneoplastic effects of lung cancer

Answer 6

• Skeletal
• Endocrine
• Neurological
• Cutaneous
• Haematologic
• Cardiovascular
• Renal

Question 7

Lung cancer investigations

Answer 7

• Chest X-Ray
• Sputum Cytology rarely used
• Bronchoscopy
• Advanced Imaging Techniques
  
  • CT scanning
  • MRI, PET scanning
  • Other imaging

Question 8

Prognostic factors in lung cancer

Answer 8

• STAGE of disease
• CLASSIFICATION: Type of disease
• Markers / Oncogenes / Gene expression profiles
• Growth Rate
• Cell Proliferation
• Immune Cell Infiltration